| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Linus Walleij | 5749 | 31.94% | 75 | 23.89% |
| Alexandre Courbot | 1642 | 9.12% | 31 | 9.87% |
| Rojhalat Ibrahim | 1270 | 7.06% | 3 | 0.96% |
| David Brownell | 1185 | 6.58% | 5 | 1.59% |
| Thierry Reding | 868 | 4.82% | 17 | 5.41% |
| Janusz Krzysztofik | 795 | 4.42% | 8 | 2.55% |
| Lukas Wunner | 662 | 3.68% | 1 | 0.32% |
| Mika Westerberg | 660 | 3.67% | 9 | 2.87% |
| Laxman Dewangan | 488 | 2.71% | 5 | 1.59% |
| Hans Verkuil | 471 | 2.62% | 5 | 1.59% |
| Bartosz Golaszewski | 373 | 2.07% | 8 | 2.55% |
| Guenter Roeck | 282 | 1.57% | 3 | 0.96% |
| Stephen Boyd | 272 | 1.51% | 7 | 2.23% |
| Lars-Peter Clausen | 255 | 1.42% | 10 | 3.18% |
| Ricardo Ribalda Delgado | 233 | 1.29% | 7 | 2.23% |
| Laura Abbott | 229 | 1.27% | 1 | 0.32% |
| Benoit Parrot | 192 | 1.07% | 1 | 0.32% |
| Christian Ruppert | 189 | 1.05% | 1 | 0.32% |
| Markus Pargmann | 177 | 0.98% | 2 | 0.64% |
| Shiraz Hashim | 175 | 0.97% | 1 | 0.32% |
| Johan Hovold | 159 | 0.88% | 7 | 2.23% |
| Andrew Jeffery | 145 | 0.81% | 1 | 0.32% |
| Bamvor Jian Zhang | 144 | 0.80% | 6 | 1.91% |
| Andy Shevchenko | 107 | 0.59% | 12 | 3.82% |
| Grant C. Likely | 103 | 0.57% | 2 | 0.64% |
| Anton Vorontsov | 99 | 0.55% | 4 | 1.27% |
| Uwe Kleine-König | 82 | 0.46% | 6 | 1.91% |
| Rasmus Villemoes | 75 | 0.42% | 1 | 0.32% |
| Philipp Zabel | 70 | 0.39% | 1 | 0.32% |
| Grygorii Strashko | 63 | 0.35% | 4 | 1.27% |
| Geert Uytterhoeven | 61 | 0.34% | 4 | 1.27% |
| Dmitry Torokhov | 60 | 0.33% | 2 | 0.64% |
| Jonas Gorski | 58 | 0.32% | 1 | 0.32% |
| Andrew Lunn | 55 | 0.31% | 1 | 0.32% |
| Charles Keepax | 53 | 0.29% | 1 | 0.32% |
| Felipe Balbi | 47 | 0.26% | 1 | 0.32% |
| Biju Das | 37 | 0.21% | 2 | 0.64% |
| Mathias Nyman | 34 | 0.19% | 1 | 0.32% |
| Björn Andersson | 33 | 0.18% | 1 | 0.32% |
| Shobhit Kumar | 31 | 0.17% | 1 | 0.32% |
| Laurent Pinchart | 23 | 0.13% | 1 | 0.32% |
| Mark Brown | 21 | 0.12% | 1 | 0.32% |
| Marc Zyngier | 20 | 0.11% | 1 | 0.32% |
| Dmitry Eremin-Solenikov | 18 | 0.10% | 1 | 0.32% |
| Julien Grossholtz | 15 | 0.08% | 1 | 0.32% |
| Vladimir Zapolskiy | 15 | 0.08% | 3 | 0.96% |
| Timur Tabi | 14 | 0.08% | 1 | 0.32% |
| Axel Lin | 13 | 0.07% | 1 | 0.32% |
| Logan Gunthorpe | 11 | 0.06% | 1 | 0.32% |
| Rafael J. Wysocki | 11 | 0.06% | 3 | 0.96% |
| Jani Nikula | 10 | 0.06% | 1 | 0.32% |
| Anatolij Gustschin | 10 | 0.06% | 1 | 0.32% |
| Sudip Mukherjee | 9 | 0.05% | 1 | 0.32% |
| Guennadi Liakhovetski | 9 | 0.05% | 2 | 0.64% |
| Tomeu Vizoso | 9 | 0.05% | 1 | 0.32% |
| Zhangfei Gao | 9 | 0.05% | 1 | 0.32% |
| Michal Nazarewicz | 7 | 0.04% | 1 | 0.32% |
| Dan Carpenter | 6 | 0.03% | 1 | 0.32% |
| Alexander Stein | 6 | 0.03% | 1 | 0.32% |
| Daniel Glöckner | 6 | 0.03% | 1 | 0.32% |
| Kees Cook | 6 | 0.03% | 1 | 0.32% |
| Arnd Bergmann | 6 | 0.03% | 1 | 0.32% |
| Boris Brezillon | 5 | 0.03% | 1 | 0.32% |
| Jean Delvare | 5 | 0.03% | 1 | 0.32% |
| Masahiro Yamada | 5 | 0.03% | 1 | 0.32% |
| Linus Torvalds | 4 | 0.02% | 2 | 0.64% |
| Dirk Behme | 4 | 0.02% | 1 | 0.32% |
| Wolfram Sang | 3 | 0.02% | 2 | 0.64% |
| Kay Sievers | 3 | 0.02% | 1 | 0.32% |
| Thomas Gleixner | 3 | 0.02% | 1 | 0.32% |
| Magnus Damm | 3 | 0.02% | 1 | 0.32% |
| Colin Cronin | 3 | 0.02% | 1 | 0.32% |
| Marcel Ziswiler | 3 | 0.02% | 1 | 0.32% |
| Tejun Heo | 3 | 0.02% | 1 | 0.32% |
| Christian Lamparter | 2 | 0.01% | 1 | 0.32% |
| Trent Piepho | 2 | 0.01% | 1 | 0.32% |
| Al Viro | 2 | 0.01% | 1 | 0.32% |
| Jarkko Nikula | 1 | 0.01% | 1 | 0.32% |
| Rob Herring | 1 | 0.01% | 1 | 0.32% |
| Heikki Krogerus | 1 | 0.01% | 1 | 0.32% |
| Martin Kaiser | 1 | 0.01% | 1 | 0.32% |
| abdoulaye berthe | 1 | 0.01% | 1 | 0.32% |
| Alexander Shiyan | 1 | 0.01% | 1 | 0.32% |
| Alexey Dobriyan | 1 | 0.01% | 1 | 0.32% |
| Ben Dooks | 1 | 0.01% | 1 | 0.32% |
| Dongsheng Wang | 1 | 0.01% | 1 | 0.32% |
| Rahul Bedarkar | 1 | 0.01% | 1 | 0.32% |
| Julia Cartwright | 1 | 0.01% | 1 | 0.32% |
| Total | 17998 | 314 |
// SPDX-License-Identifier: GPL-2.0 #include <linux/bitmap.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/interrupt.h> #include <linux/irq.h> #include <linux/spinlock.h> #include <linux/list.h> #include <linux/device.h> #include <linux/err.h> #include <linux/debugfs.h> #include <linux/seq_file.h> #include <linux/gpio.h> #include <linux/of_gpio.h> #include <linux/idr.h> #include <linux/slab.h> #include <linux/acpi.h> #include <linux/gpio/driver.h> #include <linux/gpio/machine.h> #include <linux/pinctrl/consumer.h> #include <linux/cdev.h> #include <linux/fs.h> #include <linux/uaccess.h> #include <linux/compat.h> #include <linux/anon_inodes.h> #include <linux/file.h> #include <linux/kfifo.h> #include <linux/poll.h> #include <linux/timekeeping.h> #include <uapi/linux/gpio.h> #include "gpiolib.h" #define CREATE_TRACE_POINTS #include <trace/events/gpio.h> /* Implementation infrastructure for GPIO interfaces. * * The GPIO programming interface allows for inlining speed-critical * get/set operations for common cases, so that access to SOC-integrated * GPIOs can sometimes cost only an instruction or two per bit. */ /* When debugging, extend minimal trust to callers and platform code. * Also emit diagnostic messages that may help initial bringup, when * board setup or driver bugs are most common. * * Otherwise, minimize overhead in what may be bitbanging codepaths. */ #ifdef DEBUG #define extra_checks 1 #else #define extra_checks 0 #endif /* Device and char device-related information */ static DEFINE_IDA(gpio_ida); static dev_t gpio_devt; #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */ static struct bus_type gpio_bus_type = { .name = "gpio", }; /* * Number of GPIOs to use for the fast path in set array */ #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT /* gpio_lock prevents conflicts during gpio_desc[] table updates. * While any GPIO is requested, its gpio_chip is not removable; * each GPIO's "requested" flag serves as a lock and refcount. */ DEFINE_SPINLOCK(gpio_lock); static DEFINE_MUTEX(gpio_lookup_lock); static LIST_HEAD(gpio_lookup_list); LIST_HEAD(gpio_devices); static DEFINE_MUTEX(gpio_machine_hogs_mutex); static LIST_HEAD(gpio_machine_hogs); static void gpiochip_free_hogs(struct gpio_chip *chip); static int gpiochip_add_irqchip(struct gpio_chip *gpiochip, struct lock_class_key *lock_key, struct lock_class_key *request_key); static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip); static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip); static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip); static bool gpiolib_initialized; static inline void desc_set_label(struct gpio_desc *d, const char *label) { d->label = label; } /** * gpio_to_desc - Convert a GPIO number to its descriptor * @gpio: global GPIO number * * Returns: * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO * with the given number exists in the system. */ struct gpio_desc *gpio_to_desc(unsigned gpio) { struct gpio_device *gdev; unsigned long flags; spin_lock_irqsave(&gpio_lock, flags); list_for_each_entry(gdev, &gpio_devices, list) { if (gdev->base <= gpio && gdev->base + gdev->ngpio > gpio) { spin_unlock_irqrestore(&gpio_lock, flags); return &gdev->descs[gpio - gdev->base]; } } spin_unlock_irqrestore(&gpio_lock, flags); if (!gpio_is_valid(gpio)) WARN(1, "invalid GPIO %d\n", gpio); return NULL; } EXPORT_SYMBOL_GPL(gpio_to_desc); /** * gpiochip_get_desc - get the GPIO descriptor corresponding to the given * hardware number for this chip * @chip: GPIO chip * @hwnum: hardware number of the GPIO for this chip * * Returns: * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists * in the given chip for the specified hardware number. */ struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum) { struct gpio_device *gdev = chip->gpiodev; if (hwnum >= gdev->ngpio) return ERR_PTR(-EINVAL); return &gdev->descs[hwnum]; } /** * desc_to_gpio - convert a GPIO descriptor to the integer namespace * @desc: GPIO descriptor * * This should disappear in the future but is needed since we still * use GPIO numbers for error messages and sysfs nodes. * * Returns: * The global GPIO number for the GPIO specified by its descriptor. */ int desc_to_gpio(const struct gpio_desc *desc) { return desc->gdev->base + (desc - &desc->gdev->descs[0]); } EXPORT_SYMBOL_GPL(desc_to_gpio); /** * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs * @desc: descriptor to return the chip of */ struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) { if (!desc || !desc->gdev) return NULL; return desc->gdev->chip; } EXPORT_SYMBOL_GPL(gpiod_to_chip); /* dynamic allocation of GPIOs, e.g. on a hotplugged device */ static int gpiochip_find_base(int ngpio) { struct gpio_device *gdev; int base = ARCH_NR_GPIOS - ngpio; list_for_each_entry_reverse(gdev, &gpio_devices, list) { /* found a free space? */ if (gdev->base + gdev->ngpio <= base) break; else /* nope, check the space right before the chip */ base = gdev->base - ngpio; } if (gpio_is_valid(base)) { pr_debug("%s: found new base at %d\n", __func__, base); return base; } else { pr_err("%s: cannot find free range\n", __func__); return -ENOSPC; } } /** * gpiod_get_direction - return the current direction of a GPIO * @desc: GPIO to get the direction of * * Returns 0 for output, 1 for input, or an error code in case of error. * * This function may sleep if gpiod_cansleep() is true. */ int gpiod_get_direction(struct gpio_desc *desc) { struct gpio_chip *chip; unsigned offset; int status; chip = gpiod_to_chip(desc); offset = gpio_chip_hwgpio(desc); if (!chip->get_direction) return -ENOTSUPP; status = chip->get_direction(chip, offset); if (status > 0) { /* GPIOF_DIR_IN, or other positive */ status = 1; clear_bit(FLAG_IS_OUT, &desc->flags); } if (status == 0) { /* GPIOF_DIR_OUT */ set_bit(FLAG_IS_OUT, &desc->flags); } return status; } EXPORT_SYMBOL_GPL(gpiod_get_direction); /* * Add a new chip to the global chips list, keeping the list of chips sorted * by range(means [base, base + ngpio - 1]) order. * * Return -EBUSY if the new chip overlaps with some other chip's integer * space. */ static int gpiodev_add_to_list(struct gpio_device *gdev) { struct gpio_device *prev, *next; if (list_empty(&gpio_devices)) { /* initial entry in list */ list_add_tail(&gdev->list, &gpio_devices); return 0; } next = list_entry(gpio_devices.next, struct gpio_device, list); if (gdev->base + gdev->ngpio <= next->base) { /* add before first entry */ list_add(&gdev->list, &gpio_devices); return 0; } prev = list_entry(gpio_devices.prev, struct gpio_device, list); if (prev->base + prev->ngpio <= gdev->base) { /* add behind last entry */ list_add_tail(&gdev->list, &gpio_devices); return 0; } list_for_each_entry_safe(prev, next, &gpio_devices, list) { /* at the end of the list */ if (&next->list == &gpio_devices) break; /* add between prev and next */ if (prev->base + prev->ngpio <= gdev->base && gdev->base + gdev->ngpio <= next->base) { list_add(&gdev->list, &prev->list); return 0; } } dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n"); return -EBUSY; } /* * Convert a GPIO name to its descriptor */ static struct gpio_desc *gpio_name_to_desc(const char * const name) { struct gpio_device *gdev; unsigned long flags; spin_lock_irqsave(&gpio_lock, flags); list_for_each_entry(gdev, &gpio_devices, list) { int i; for (i = 0; i != gdev->ngpio; ++i) { struct gpio_desc *desc = &gdev->descs[i]; if (!desc->name || !name) continue; if (!strcmp(desc->name, name)) { spin_unlock_irqrestore(&gpio_lock, flags); return desc; } } } spin_unlock_irqrestore(&gpio_lock, flags); return NULL; } /* * Takes the names from gc->names and checks if they are all unique. If they * are, they are assigned to their gpio descriptors. * * Warning if one of the names is already used for a different GPIO. */ static int gpiochip_set_desc_names(struct gpio_chip *gc) { struct gpio_device *gdev = gc->gpiodev; int i; if (!gc->names) return 0; /* First check all names if they are unique */ for (i = 0; i != gc->ngpio; ++i) { struct gpio_desc *gpio; gpio = gpio_name_to_desc(gc->names[i]); if (gpio) dev_warn(&gdev->dev, "Detected name collision for GPIO name '%s'\n", gc->names[i]); } /* Then add all names to the GPIO descriptors */ for (i = 0; i != gc->ngpio; ++i) gdev->descs[i].name = gc->names[i]; return 0; } static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip) { unsigned long *p; p = kmalloc_array(BITS_TO_LONGS(chip->ngpio), sizeof(*p), GFP_KERNEL); if (!p) return NULL; /* Assume by default all GPIOs are valid */ bitmap_fill(p, chip->ngpio); return p; } static int gpiochip_alloc_valid_mask(struct gpio_chip *gpiochip) { #ifdef CONFIG_OF_GPIO int size; struct device_node *np = gpiochip->of_node; size = of_property_count_u32_elems(np, "gpio-reserved-ranges"); if (size > 0 && size % 2 == 0) gpiochip->need_valid_mask = true; #endif if (!gpiochip->need_valid_mask) return 0; gpiochip->valid_mask = gpiochip_allocate_mask(gpiochip); if (!gpiochip->valid_mask) return -ENOMEM; return 0; } static int gpiochip_init_valid_mask(struct gpio_chip *gpiochip) { if (gpiochip->init_valid_mask) return gpiochip->init_valid_mask(gpiochip); return 0; } static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip) { kfree(gpiochip->valid_mask); gpiochip->valid_mask = NULL; } bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip, unsigned int offset) { /* No mask means all valid */ if (likely(!gpiochip->valid_mask)) return true; return test_bit(offset, gpiochip->valid_mask); } EXPORT_SYMBOL_GPL(gpiochip_line_is_valid); /* * GPIO line handle management */ /** * struct linehandle_state - contains the state of a userspace handle * @gdev: the GPIO device the handle pertains to * @label: consumer label used to tag descriptors * @descs: the GPIO descriptors held by this handle * @numdescs: the number of descriptors held in the descs array */ struct linehandle_state { struct gpio_device *gdev; const char *label; struct gpio_desc *descs[GPIOHANDLES_MAX]; u32 numdescs; }; #define GPIOHANDLE_REQUEST_VALID_FLAGS \ (GPIOHANDLE_REQUEST_INPUT | \ GPIOHANDLE_REQUEST_OUTPUT | \ GPIOHANDLE_REQUEST_ACTIVE_LOW | \ GPIOHANDLE_REQUEST_OPEN_DRAIN | \ GPIOHANDLE_REQUEST_OPEN_SOURCE) static long linehandle_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) { struct linehandle_state *lh = filep->private_data; void __user *ip = (void __user *)arg; struct gpiohandle_data ghd; DECLARE_BITMAP(vals, GPIOHANDLES_MAX); int i; if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) { /* NOTE: It's ok to read values of output lines. */ int ret = gpiod_get_array_value_complex(false, true, lh->numdescs, lh->descs, NULL, vals); if (ret) return ret; memset(&ghd, 0, sizeof(ghd)); for (i = 0; i < lh->numdescs; i++) ghd.values[i] = test_bit(i, vals); if (copy_to_user(ip, &ghd, sizeof(ghd))) return -EFAULT; return 0; } else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) { /* * All line descriptors were created at once with the same * flags so just check if the first one is really output. */ if (!test_bit(FLAG_IS_OUT, &lh->descs[0]->flags)) return -EPERM; if (copy_from_user(&ghd, ip, sizeof(ghd))) return -EFAULT; /* Clamp all values to [0,1] */ for (i = 0; i < lh->numdescs; i++) __assign_bit(i, vals, ghd.values[i]); /* Reuse the array setting function */ return gpiod_set_array_value_complex(false, true, lh->numdescs, lh->descs, NULL, vals); } return -EINVAL; } #ifdef CONFIG_COMPAT static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd, unsigned long arg) { return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg)); } #endif static int linehandle_release(struct inode *inode, struct file *filep) { struct linehandle_state *lh = filep->private_data; struct gpio_device *gdev = lh->gdev; int i; for (i = 0; i < lh->numdescs; i++) gpiod_free(lh->descs[i]); kfree(lh->label); kfree(lh); put_device(&gdev->dev); return 0; } static const struct file_operations linehandle_fileops = { .release = linehandle_release, .owner = THIS_MODULE, .llseek = noop_llseek, .unlocked_ioctl = linehandle_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = linehandle_ioctl_compat, #endif }; static int linehandle_create(struct gpio_device *gdev, void __user *ip) { struct gpiohandle_request handlereq; struct linehandle_state *lh; struct file *file; int fd, i, count = 0, ret; u32 lflags; if (copy_from_user(&handlereq, ip, sizeof(handlereq))) return -EFAULT; if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX)) return -EINVAL; lflags = handlereq.flags; /* Return an error if an unknown flag is set */ if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) return -EINVAL; /* * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If * the hardware actually supports enabling both at the same time the * electrical result would be disastrous. */ if ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) && (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)) return -EINVAL; /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */ if (!(lflags & GPIOHANDLE_REQUEST_OUTPUT) && ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) || (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))) return -EINVAL; lh = kzalloc(sizeof(*lh), GFP_KERNEL); if (!lh) return -ENOMEM; lh->gdev = gdev; get_device(&gdev->dev); /* Make sure this is terminated */ handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0'; if (strlen(handlereq.consumer_label)) { lh->label = kstrdup(handlereq.consumer_label, GFP_KERNEL); if (!lh->label) { ret = -ENOMEM; goto out_free_lh; } } /* Request each GPIO */ for (i = 0; i < handlereq.lines; i++) { u32 offset = handlereq.lineoffsets[i]; struct gpio_desc *desc; if (offset >= gdev->ngpio) { ret = -EINVAL; goto out_free_descs; } desc = &gdev->descs[offset]; ret = gpiod_request(desc, lh->label); if (ret) goto out_free_descs; lh->descs[i] = desc; count = i + 1; if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW) set_bit(FLAG_ACTIVE_LOW, &desc->flags); if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) set_bit(FLAG_OPEN_DRAIN, &desc->flags); if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE) set_bit(FLAG_OPEN_SOURCE, &desc->flags); ret = gpiod_set_transitory(desc, false); if (ret < 0) goto out_free_descs; /* * Lines have to be requested explicitly for input * or output, else the line will be treated "as is". */ if (lflags & GPIOHANDLE_REQUEST_OUTPUT) { int val = !!handlereq.default_values[i]; ret = gpiod_direction_output(desc, val); if (ret) goto out_free_descs; } else if (lflags & GPIOHANDLE_REQUEST_INPUT) { ret = gpiod_direction_input(desc); if (ret) goto out_free_descs; } dev_dbg(&gdev->dev, "registered chardev handle for line %d\n", offset); } /* Let i point at the last handle */ i--; lh->numdescs = handlereq.lines; fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC); if (fd < 0) { ret = fd; goto out_free_descs; } file = anon_inode_getfile("gpio-linehandle", &linehandle_fileops, lh, O_RDONLY | O_CLOEXEC); if (IS_ERR(file)) { ret = PTR_ERR(file); goto out_put_unused_fd; } handlereq.fd = fd; if (copy_to_user(ip, &handlereq, sizeof(handlereq))) { /* * fput() will trigger the release() callback, so do not go onto * the regular error cleanup path here. */ fput(file); put_unused_fd(fd); return -EFAULT; } fd_install(fd, file); dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n", lh->numdescs); return 0; out_put_unused_fd: put_unused_fd(fd); out_free_descs: for (i = 0; i < count; i++) gpiod_free(lh->descs[i]); kfree(lh->label); out_free_lh: kfree(lh); put_device(&gdev->dev); return ret; } /* * GPIO line event management */ /** * struct lineevent_state - contains the state of a userspace event * @gdev: the GPIO device the event pertains to * @label: consumer label used to tag descriptors * @desc: the GPIO descriptor held by this event * @eflags: the event flags this line was requested with * @irq: the interrupt that trigger in response to events on this GPIO * @wait: wait queue that handles blocking reads of events * @events: KFIFO for the GPIO events * @read_lock: mutex lock to protect reads from colliding with adding * new events to the FIFO * @timestamp: cache for the timestamp storing it between hardirq * and IRQ thread, used to bring the timestamp close to the actual * event */ struct lineevent_state { struct gpio_device *gdev; const char *label; struct gpio_desc *desc; u32 eflags; int irq; wait_queue_head_t wait; DECLARE_KFIFO(events, struct gpioevent_data, 16); struct mutex read_lock; u64 timestamp; }; #define GPIOEVENT_REQUEST_VALID_FLAGS \ (GPIOEVENT_REQUEST_RISING_EDGE | \ GPIOEVENT_REQUEST_FALLING_EDGE) static __poll_t lineevent_poll(struct file *filep, struct poll_table_struct *wait) { struct lineevent_state *le = filep->private_data; __poll_t events = 0; poll_wait(filep, &le->wait, wait); if (!kfifo_is_empty(&le->events)) events = EPOLLIN | EPOLLRDNORM; return events; } static ssize_t lineevent_read(struct file *filep, char __user *buf, size_t count, loff_t *f_ps) { struct lineevent_state *le = filep->private_data; unsigned int copied; int ret; if (count < sizeof(struct gpioevent_data)) return -EINVAL; do { if (kfifo_is_empty(&le->events)) { if (filep->f_flags & O_NONBLOCK) return -EAGAIN; ret = wait_event_interruptible(le->wait, !kfifo_is_empty(&le->events)); if (ret) return ret; } if (mutex_lock_interruptible(&le->read_lock)) return -ERESTARTSYS; ret = kfifo_to_user(&le->events, buf, count, &copied); mutex_unlock(&le->read_lock); if (ret) return ret; /* * If we couldn't read anything from the fifo (a different * thread might have been faster) we either return -EAGAIN if * the file descriptor is non-blocking, otherwise we go back to * sleep and wait for more data to arrive. */ if (copied == 0 && (filep->f_flags & O_NONBLOCK)) return -EAGAIN; } while (copied == 0); return copied; } static int lineevent_release(struct inode *inode, struct file *filep) { struct lineevent_state *le = filep->private_data; struct gpio_device *gdev = le->gdev; free_irq(le->irq, le); gpiod_free(le->desc); kfree(le->label); kfree(le); put_device(&gdev->dev); return 0; } static long lineevent_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) { struct lineevent_state *le = filep->private_data; void __user *ip = (void __user *)arg; struct gpiohandle_data ghd; /* * We can get the value for an event line but not set it, * because it is input by definition. */ if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) { int val; memset(&ghd, 0, sizeof(ghd)); val = gpiod_get_value_cansleep(le->desc); if (val < 0) return val; ghd.values[0] = val; if (copy_to_user(ip, &ghd, sizeof(ghd))) return -EFAULT; return 0; } return -EINVAL; } #ifdef CONFIG_COMPAT static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd, unsigned long arg) { return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg)); } #endif static const struct file_operations lineevent_fileops = { .release = lineevent_release, .read = lineevent_read, .poll = lineevent_poll, .owner = THIS_MODULE, .llseek = noop_llseek, .unlocked_ioctl = lineevent_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = lineevent_ioctl_compat, #endif }; static irqreturn_t lineevent_irq_thread(int irq, void *p) { struct lineevent_state *le = p; struct gpioevent_data ge; int ret; /* Do not leak kernel stack to userspace */ memset(&ge, 0, sizeof(ge)); ge.timestamp = le->timestamp; if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) { int level = gpiod_get_value_cansleep(le->desc); if (level) /* Emit low-to-high event */ ge.id = GPIOEVENT_EVENT_RISING_EDGE; else /* Emit high-to-low event */ ge.id = GPIOEVENT_EVENT_FALLING_EDGE; } else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) { /* Emit low-to-high event */ ge.id = GPIOEVENT_EVENT_RISING_EDGE; } else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) { /* Emit high-to-low event */ ge.id = GPIOEVENT_EVENT_FALLING_EDGE; } else { return IRQ_NONE; } ret = kfifo_put(&le->events, ge); if (ret != 0) wake_up_poll(&le->wait, EPOLLIN); return IRQ_HANDLED; } static irqreturn_t lineevent_irq_handler(int irq, void *p) { struct lineevent_state *le = p; /* * Just store the timestamp in hardirq context so we get it as * close in time as possible to the actual event. */ le->timestamp = ktime_get_real_ns(); return IRQ_WAKE_THREAD; } static int lineevent_create(struct gpio_device *gdev, void __user *ip) { struct gpioevent_request eventreq; struct lineevent_state *le; struct gpio_desc *desc; struct file *file; u32 offset; u32 lflags; u32 eflags; int fd; int ret; int irqflags = 0; if (copy_from_user(&eventreq, ip, sizeof(eventreq))) return -EFAULT; le = kzalloc(sizeof(*le), GFP_KERNEL); if (!le) return -ENOMEM; le->gdev = gdev; get_device(&gdev->dev); /* Make sure this is terminated */ eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0'; if (strlen(eventreq.consumer_label)) { le->label = kstrdup(eventreq.consumer_label, GFP_KERNEL); if (!le->label) { ret = -ENOMEM; goto out_free_le; } } offset = eventreq.lineoffset; lflags = eventreq.handleflags; eflags = eventreq.eventflags; if (offset >= gdev->ngpio) { ret = -EINVAL; goto out_free_label; } /* Return an error if a unknown flag is set */ if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) || (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS)) { ret = -EINVAL; goto out_free_label; } /* This is just wrong: we don't look for events on output lines */ if (lflags & GPIOHANDLE_REQUEST_OUTPUT) { ret = -EINVAL; goto out_free_label; } desc = &gdev->descs[offset]; ret = gpiod_request(desc, le->label); if (ret) goto out_free_label; le->desc = desc; le->eflags = eflags; if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW) set_bit(FLAG_ACTIVE_LOW, &desc->flags); if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) set_bit(FLAG_OPEN_DRAIN, &desc->flags); if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE) set_bit(FLAG_OPEN_SOURCE, &desc->flags); ret = gpiod_direction_input(desc); if (ret) goto out_free_desc; le->irq = gpiod_to_irq(desc); if (le->irq <= 0) { ret = -ENODEV; goto out_free_desc; } if (eflags & GPIOEVENT_REQUEST_RISING_EDGE) irqflags |= IRQF_TRIGGER_RISING; if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE) irqflags |= IRQF_TRIGGER_FALLING; irqflags |= IRQF_ONESHOT; INIT_KFIFO(le->events); init_waitqueue_head(&le->wait); mutex_init(&le->read_lock); /* Request a thread to read the events */ ret = request_threaded_irq(le->irq, lineevent_irq_handler, lineevent_irq_thread, irqflags, le->label, le); if (ret) goto out_free_desc; fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC); if (fd < 0) { ret = fd; goto out_free_irq; } file = anon_inode_getfile("gpio-event", &lineevent_fileops, le, O_RDONLY | O_CLOEXEC); if (IS_ERR(file)) { ret = PTR_ERR(file); goto out_put_unused_fd; } eventreq.fd = fd; if (copy_to_user(ip, &eventreq, sizeof(eventreq))) { /* * fput() will trigger the release() callback, so do not go onto * the regular error cleanup path here. */ fput(file); put_unused_fd(fd); return -EFAULT; } fd_install(fd, file); return 0; out_put_unused_fd: put_unused_fd(fd); out_free_irq: free_irq(le->irq, le); out_free_desc: gpiod_free(le->desc); out_free_label: kfree(le->label); out_free_le: kfree(le); put_device(&gdev->dev); return ret; } /* * gpio_ioctl() - ioctl handler for the GPIO chardev */ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { struct gpio_device *gdev = filp->private_data; struct gpio_chip *chip = gdev->chip; void __user *ip = (void __user *)arg; /* We fail any subsequent ioctl():s when the chip is gone */ if (!chip) return -ENODEV; /* Fill in the struct and pass to userspace */ if (cmd == GPIO_GET_CHIPINFO_IOCTL) { struct gpiochip_info chipinfo; memset(&chipinfo, 0, sizeof(chipinfo)); strncpy(chipinfo.name, dev_name(&gdev->dev), sizeof(chipinfo.name)); chipinfo.name[sizeof(chipinfo.name)-1] = '\0'; strncpy(chipinfo.label, gdev->label, sizeof(chipinfo.label)); chipinfo.label[sizeof(chipinfo.label)-1] = '\0'; chipinfo.lines = gdev->ngpio; if (copy_to_user(ip, &chipinfo, sizeof(chipinfo))) return -EFAULT; return 0; } else if (cmd == GPIO_GET_LINEINFO_IOCTL) { struct gpioline_info lineinfo; struct gpio_desc *desc; if (copy_from_user(&lineinfo, ip, sizeof(lineinfo))) return -EFAULT; if (lineinfo.line_offset >= gdev->ngpio) return -EINVAL; desc = &gdev->descs[lineinfo.line_offset]; if (desc->name) { strncpy(lineinfo.name, desc->name, sizeof(lineinfo.name)); lineinfo.name[sizeof(lineinfo.name)-1] = '\0'; } else { lineinfo.name[0] = '\0'; } if (desc->label) { strncpy(lineinfo.consumer, desc->label, sizeof(lineinfo.consumer)); lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0'; } else { lineinfo.consumer[0] = '\0'; } /* * Userspace only need to know that the kernel is using * this GPIO so it can't use it. */ lineinfo.flags = 0; if (test_bit(FLAG_REQUESTED, &desc->flags) || test_bit(FLAG_IS_HOGGED, &desc->flags) || test_bit(FLAG_USED_AS_IRQ, &desc->flags) || test_bit(FLAG_EXPORT, &desc->flags) || test_bit(FLAG_SYSFS, &desc->flags)) lineinfo.flags |= GPIOLINE_FLAG_KERNEL; if (test_bit(FLAG_IS_OUT, &desc->flags)) lineinfo.flags |= GPIOLINE_FLAG_IS_OUT; if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW; if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) lineinfo.flags |= GPIOLINE_FLAG_OPEN_DRAIN; if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) lineinfo.flags |= GPIOLINE_FLAG_OPEN_SOURCE; if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) return -EFAULT; return 0; } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) { return linehandle_create(gdev, ip); } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) { return lineevent_create(gdev, ip); } return -EINVAL; } #ifdef CONFIG_COMPAT static long gpio_ioctl_compat(struct file *filp, unsigned int cmd, unsigned long arg) { return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg)); } #endif /** * gpio_chrdev_open() - open the chardev for ioctl operations * @inode: inode for this chardev * @filp: file struct for storing private data * Returns 0 on success */ static int gpio_chrdev_open(struct inode *inode, struct file *filp) { struct gpio_device *gdev = container_of(inode->i_cdev, struct gpio_device, chrdev); /* Fail on open if the backing gpiochip is gone */ if (!gdev->chip) return -ENODEV; get_device(&gdev->dev); filp->private_data = gdev; return nonseekable_open(inode, filp); } /** * gpio_chrdev_release() - close chardev after ioctl operations * @inode: inode for this chardev * @filp: file struct for storing private data * Returns 0 on success */ static int gpio_chrdev_release(struct inode *inode, struct file *filp) { struct gpio_device *gdev = container_of(inode->i_cdev, struct gpio_device, chrdev); put_device(&gdev->dev); return 0; } static const struct file_operations gpio_fileops = { .release = gpio_chrdev_release, .open = gpio_chrdev_open, .owner = THIS_MODULE, .llseek = no_llseek, .unlocked_ioctl = gpio_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = gpio_ioctl_compat, #endif }; static void gpiodevice_release(struct device *dev) { struct gpio_device *gdev = dev_get_drvdata(dev); list_del(&gdev->list); ida_simple_remove(&gpio_ida, gdev->id); kfree_const(gdev->label); kfree(gdev->descs); kfree(gdev); } static int gpiochip_setup_dev(struct gpio_device *gdev) { int status; cdev_init(&gdev->chrdev, &gpio_fileops); gdev->chrdev.owner = THIS_MODULE; gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id); status = cdev_device_add(&gdev->chrdev, &gdev->dev); if (status) return status; chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n", MAJOR(gpio_devt), gdev->id); status = gpiochip_sysfs_register(gdev); if (status) goto err_remove_device; /* From this point, the .release() function cleans up gpio_device */ gdev->dev.release = gpiodevice_release; pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n", __func__, gdev->base, gdev->base + gdev->ngpio - 1, dev_name(&gdev->dev), gdev->chip->label ? : "generic"); return 0; err_remove_device: cdev_device_del(&gdev->chrdev, &gdev->dev); return status; } static void gpiochip_machine_hog(struct gpio_chip *chip, struct gpiod_hog *hog) { struct gpio_desc *desc; int rv; desc = gpiochip_get_desc(chip, hog->chip_hwnum); if (IS_ERR(desc)) { pr_err("%s: unable to get GPIO desc: %ld\n", __func__, PTR_ERR(desc)); return; } if (test_bit(FLAG_IS_HOGGED, &desc->flags)) return; rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags); if (rv) pr_err("%s: unable to hog GPIO line (%s:%u): %d\n", __func__, chip->label, hog->chip_hwnum, rv); } static void machine_gpiochip_add(struct gpio_chip *chip) { struct gpiod_hog *hog; mutex_lock(&gpio_machine_hogs_mutex); list_for_each_entry(hog, &gpio_machine_hogs, list) { if (!strcmp(chip->label, hog->chip_label)) gpiochip_machine_hog(chip, hog); } mutex_unlock(&gpio_machine_hogs_mutex); } static void gpiochip_setup_devs(void) { struct gpio_device *gdev; int err; list_for_each_entry(gdev, &gpio_devices, list) { err = gpiochip_setup_dev(gdev); if (err) pr_err("%s: Failed to initialize gpio device (%d)\n", dev_name(&gdev->dev), err); } } int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data, struct lock_class_key *lock_key, struct lock_class_key *request_key) { unsigned long flags; int status = 0; unsigned i; int base = chip->base; struct gpio_device *gdev; /* * First: allocate and populate the internal stat container, and * set up the struct device. */ gdev = kzalloc(sizeof(*gdev), GFP_KERNEL); if (!gdev) return -ENOMEM; gdev->dev.bus = &gpio_bus_type; gdev->chip = chip; chip->gpiodev = gdev; if (chip->parent) { gdev->dev.parent = chip->parent; gdev->dev.of_node = chip->parent->of_node; } #ifdef CONFIG_OF_GPIO /* If the gpiochip has an assigned OF node this takes precedence */ if (chip->of_node) gdev->dev.of_node = chip->of_node; else chip->of_node = gdev->dev.of_node; #endif gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL); if (gdev->id < 0) { status = gdev->id; goto err_free_gdev; } dev_set_name(&gdev->dev, "gpiochip%d", gdev->id); device_initialize(&gdev->dev); dev_set_drvdata(&gdev->dev, gdev); if (chip->parent && chip->parent->driver) gdev->owner = chip->parent->driver->owner; else if (chip->owner) /* TODO: remove chip->owner */ gdev->owner = chip->owner; else gdev->owner = THIS_MODULE; gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL); if (!gdev->descs) { status = -ENOMEM; goto err_free_ida; } if (chip->ngpio == 0) { chip_err(chip, "tried to insert a GPIO chip with zero lines\n"); status = -EINVAL; goto err_free_descs; } if (chip->ngpio > FASTPATH_NGPIO) chip_warn(chip, "line cnt %u is greater than fast path cnt %u\n", chip->ngpio, FASTPATH_NGPIO); gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL); if (!gdev->label) { status = -ENOMEM; goto err_free_descs; } gdev->ngpio = chip->ngpio; gdev->data = data; spin_lock_irqsave(&gpio_lock, flags); /* * TODO: this allocates a Linux GPIO number base in the global * GPIO numberspace for this chip. In the long run we want to * get *rid* of this numberspace and use only descriptors, but * it may be a pipe dream. It will not happen before we get rid * of the sysfs interface anyways. */ if (base < 0) { base = gpiochip_find_base(chip->ngpio); if (base < 0) { status = base; spin_unlock_irqrestore(&gpio_lock, flags); goto err_free_label; } /* * TODO: it should not be necessary to reflect the assigned * base outside of the GPIO subsystem. Go over drivers and * see if anyone makes use of this, else drop this and assign * a poison instead. */ chip->base = base; } gdev->base = base; status = gpiodev_add_to_list(gdev); if (status) { spin_unlock_irqrestore(&gpio_lock, flags); goto err_free_label; } spin_unlock_irqrestore(&gpio_lock, flags); for (i = 0; i < chip->ngpio; i++) gdev->descs[i].gdev = gdev; #ifdef CONFIG_PINCTRL INIT_LIST_HEAD(&gdev->pin_ranges); #endif status = gpiochip_set_desc_names(chip); if (status) goto err_remove_from_list; status = gpiochip_irqchip_init_valid_mask(chip); if (status) goto err_remove_from_list; status = gpiochip_alloc_valid_mask(chip); if (status) goto err_remove_irqchip_mask; status = gpiochip_add_irqchip(chip, lock_key, request_key); if (status) goto err_remove_chip; status = of_gpiochip_add(chip); if (status) goto err_remove_chip; status = gpiochip_init_valid_mask(chip); if (status) goto err_remove_chip; for (i = 0; i < chip->ngpio; i++) { struct gpio_desc *desc = &gdev->descs[i]; if (chip->get_direction && gpiochip_line_is_valid(chip, i)) desc->flags = !chip->get_direction(chip, i) ? (1 << FLAG_IS_OUT) : 0; else desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0; } acpi_gpiochip_add(chip); machine_gpiochip_add(chip); /* * By first adding the chardev, and then adding the device, * we get a device node entry in sysfs under * /sys/bus/gpio/devices/gpiochipN/dev that can be used for * coldplug of device nodes and other udev business. * We can do this only if gpiolib has been initialized. * Otherwise, defer until later. */ if (gpiolib_initialized) { status = gpiochip_setup_dev(gdev); if (status) goto err_remove_chip; } return 0; err_remove_chip: acpi_gpiochip_remove(chip); gpiochip_free_hogs(chip); of_gpiochip_remove(chip); gpiochip_free_valid_mask(chip); err_remove_irqchip_mask: gpiochip_irqchip_free_valid_mask(chip); err_remove_from_list: spin_lock_irqsave(&gpio_lock, flags); list_del(&gdev->list); spin_unlock_irqrestore(&gpio_lock, flags); err_free_label: kfree_const(gdev->label); err_free_descs: kfree(gdev->descs); err_free_ida: ida_simple_remove(&gpio_ida, gdev->id); err_free_gdev: /* failures here can mean systems won't boot... */ pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__, gdev->base, gdev->base + gdev->ngpio - 1, chip->label ? : "generic", status); kfree(gdev); return status; } EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key); /** * gpiochip_get_data() - get per-subdriver data for the chip * @chip: GPIO chip * * Returns: * The per-subdriver data for the chip. */ void *gpiochip_get_data(struct gpio_chip *chip) { return chip->gpiodev->data; } EXPORT_SYMBOL_GPL(gpiochip_get_data); /** * gpiochip_remove() - unregister a gpio_chip * @chip: the chip to unregister * * A gpio_chip with any GPIOs still requested may not be removed. */ void gpiochip_remove(struct gpio_chip *chip) { struct gpio_device *gdev = chip->gpiodev; struct gpio_desc *desc; unsigned long flags; unsigned i; bool requested = false; /* FIXME: should the legacy sysfs handling be moved to gpio_device? */ gpiochip_sysfs_unregister(gdev); gpiochip_free_hogs(chip); /* Numb the device, cancelling all outstanding operations */ gdev->chip = NULL; gpiochip_irqchip_remove(chip); acpi_gpiochip_remove(chip); gpiochip_remove_pin_ranges(chip); of_gpiochip_remove(chip); gpiochip_free_valid_mask(chip); /* * We accept no more calls into the driver from this point, so * NULL the driver data pointer */ gdev->data = NULL; spin_lock_irqsave(&gpio_lock, flags); for (i = 0; i < gdev->ngpio; i++) { desc = &gdev->descs[i]; if (test_bit(FLAG_REQUESTED, &desc->flags)) requested = true; } spin_unlock_irqrestore(&gpio_lock, flags); if (requested) dev_crit(&gdev->dev, "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n"); /* * The gpiochip side puts its use of the device to rest here: * if there are no userspace clients, the chardev and device will * be removed, else it will be dangling until the last user is * gone. */ cdev_device_del(&gdev->chrdev, &gdev->dev); put_device(&gdev->dev); } EXPORT_SYMBOL_GPL(gpiochip_remove); static void devm_gpio_chip_release(struct device *dev, void *res) { struct gpio_chip *chip = *(struct gpio_chip **)res; gpiochip_remove(chip); } static int devm_gpio_chip_match(struct device *dev, void *res, void *data) { struct gpio_chip **r = res; if (!r || !*r) { WARN_ON(!r || !*r); return 0; } return *r == data; } /** * devm_gpiochip_add_data() - Resource manager gpiochip_add_data() * @dev: pointer to the device that gpio_chip belongs to. * @chip: the chip to register, with chip->base initialized * @data: driver-private data associated with this chip * * Context: potentially before irqs will work * * The gpio chip automatically be released when the device is unbound. * * Returns: * A negative errno if the chip can't be registered, such as because the * chip->base is invalid or already associated with a different chip. * Otherwise it returns zero as a success code. */ int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip, void *data) { struct gpio_chip **ptr; int ret; ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr), GFP_KERNEL); if (!ptr) return -ENOMEM; ret = gpiochip_add_data(chip, data); if (ret < 0) { devres_free(ptr); return ret; } *ptr = chip; devres_add(dev, ptr); return 0; } EXPORT_SYMBOL_GPL(devm_gpiochip_add_data); /** * devm_gpiochip_remove() - Resource manager of gpiochip_remove() * @dev: device for which which resource was allocated * @chip: the chip to remove * * A gpio_chip with any GPIOs still requested may not be removed. */ void devm_gpiochip_remove(struct device *dev, struct gpio_chip *chip) { int ret; ret = devres_release(dev, devm_gpio_chip_release, devm_gpio_chip_match, chip); WARN_ON(ret); } EXPORT_SYMBOL_GPL(devm_gpiochip_remove); /** * gpiochip_find() - iterator for locating a specific gpio_chip * @data: data to pass to match function * @match: Callback function to check gpio_chip * * Similar to bus_find_device. It returns a reference to a gpio_chip as * determined by a user supplied @match callback. The callback should return * 0 if the device doesn't match and non-zero if it does. If the callback is * non-zero, this function will return to the caller and not iterate over any * more gpio_chips. */ struct gpio_chip *gpiochip_find(void *data, int (*match)(struct gpio_chip *chip, void *data)) { struct gpio_device *gdev; struct gpio_chip *chip = NULL; unsigned long flags; spin_lock_irqsave(&gpio_lock, flags); list_for_each_entry(gdev, &gpio_devices, list) if (gdev->chip && match(gdev->chip, data)) { chip = gdev->chip; break; } spin_unlock_irqrestore(&gpio_lock, flags); return chip; } EXPORT_SYMBOL_GPL(gpiochip_find); static int gpiochip_match_name(struct gpio_chip *chip, void *data) { const char *name = data; return !strcmp(chip->label, name); } static struct gpio_chip *find_chip_by_name(const char *name) { return gpiochip_find((void *)name, gpiochip_match_name); } #ifdef CONFIG_GPIOLIB_IRQCHIP /* * The following is irqchip helper code for gpiochips. */ static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip) { if (!gpiochip->irq.need_valid_mask) return 0; gpiochip->irq.valid_mask = gpiochip_allocate_mask(gpiochip); if (!gpiochip->irq.valid_mask) return -ENOMEM; return 0; } static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip) { kfree(gpiochip->irq.valid_mask); gpiochip->irq.valid_mask = NULL; } bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip, unsigned int offset) { if (!gpiochip_line_is_valid(gpiochip, offset)) return false; /* No mask means all valid */ if (likely(!gpiochip->irq.valid_mask)) return true; return test_bit(offset, gpiochip->irq.valid_mask); } EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid); /** * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip * @gpiochip: the gpiochip to set the irqchip chain to * @parent_irq: the irq number corresponding to the parent IRQ for this * chained irqchip * @parent_handler: the parent interrupt handler for the accumulated IRQ * coming out of the gpiochip. If the interrupt is nested rather than * cascaded, pass NULL in this handler argument */ static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gpiochip, unsigned int parent_irq, irq_flow_handler_t parent_handler) { if (!gpiochip->irq.domain) { chip_err(gpiochip, "called %s before setting up irqchip\n", __func__); return; } if (parent_handler) { if (gpiochip->can_sleep) { chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n"); return; } /* * The parent irqchip is already using the chip_data for this * irqchip, so our callbacks simply use the handler_data. */ irq_set_chained_handler_and_data(parent_irq, parent_handler, gpiochip); gpiochip->irq.parent_irq = parent_irq; gpiochip->irq.parents = &gpiochip->irq.parent_irq; gpiochip->irq.num_parents = 1; } } /** * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip * @gpiochip: the gpiochip to set the irqchip chain to * @irqchip: the irqchip to chain to the gpiochip * @parent_irq: the irq number corresponding to the parent IRQ for this * chained irqchip * @parent_handler: the parent interrupt handler for the accumulated IRQ * coming out of the gpiochip. */ void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, struct irq_chip *irqchip, unsigned int parent_irq, irq_flow_handler_t parent_handler) { if (gpiochip->irq.threaded) { chip_err(gpiochip, "tried to chain a threaded gpiochip\n"); return; } gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, parent_handler); } EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip); /** * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip * @gpiochip: the gpiochip to set the irqchip nested handler to * @irqchip: the irqchip to nest to the gpiochip * @parent_irq: the irq number corresponding to the parent IRQ for this * nested irqchip */ void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip, struct irq_chip *irqchip, unsigned int parent_irq) { gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, NULL); } EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip); /** * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip * @d: the irqdomain used by this irqchip * @irq: the global irq number used by this GPIO irqchip irq * @hwirq: the local IRQ/GPIO line offset on this gpiochip * * This function will set up the mapping for a certain IRQ line on a * gpiochip by assigning the gpiochip as chip data, and using the irqchip * stored inside the gpiochip. */ int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hwirq) { struct gpio_chip *chip = d->host_data; int err = 0; if (!gpiochip_irqchip_irq_valid(chip, hwirq)) return -ENXIO; irq_set_chip_data(irq, chip); /* * This lock class tells lockdep that GPIO irqs are in a different * category than their parents, so it won't report false recursion. */ irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key); irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler); /* Chips that use nested thread handlers have them marked */ if (chip->irq.threaded) irq_set_nested_thread(irq, 1); irq_set_noprobe(irq); if (chip->irq.num_parents == 1) err = irq_set_parent(irq, chip->irq.parents[0]); else if (chip->irq.map) err = irq_set_parent(irq, chip->irq.map[hwirq]); if (err < 0) return err; /* * No set-up of the hardware will happen if IRQ_TYPE_NONE * is passed as default type. */ if (chip->irq.default_type != IRQ_TYPE_NONE) irq_set_irq_type(irq, chip->irq.default_type); return 0; } EXPORT_SYMBOL_GPL(gpiochip_irq_map); void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) { struct gpio_chip *chip = d->host_data; if (chip->irq.threaded) irq_set_nested_thread(irq, 0); irq_set_chip_and_handler(irq, NULL, NULL); irq_set_chip_data(irq, NULL); } EXPORT_SYMBOL_GPL(gpiochip_irq_unmap); static const struct irq_domain_ops gpiochip_domain_ops = { .map = gpiochip_irq_map, .unmap = gpiochip_irq_unmap, /* Virtually all GPIO irqchips are twocell:ed */ .xlate = irq_domain_xlate_twocell, }; static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset) { if (!gpiochip_irqchip_irq_valid(chip, offset)) return -ENXIO; return irq_create_mapping(chip->irq.domain, offset); } static int gpiochip_irq_reqres(struct irq_data *d) { struct gpio_chip *chip = irq_data_get_irq_chip_data(d); return gpiochip_reqres_irq(chip, d->hwirq); } static void gpiochip_irq_relres(struct irq_data *d) { struct gpio_chip *chip = irq_data_get_irq_chip_data(d); gpiochip_relres_irq(chip, d->hwirq); } static void gpiochip_irq_enable(struct irq_data *d) { struct gpio_chip *chip = irq_data_get_irq_chip_data(d); gpiochip_enable_irq(chip, d->hwirq); if (chip->irq.irq_enable) chip->irq.irq_enable(d); else chip->irq.chip->irq_unmask(d); } static void gpiochip_irq_disable(struct irq_data *d) { struct gpio_chip *chip = irq_data_get_irq_chip_data(d); if (chip->irq.irq_disable) chip->irq.irq_disable(d); else chip->irq.chip->irq_mask(d); gpiochip_disable_irq(chip, d->hwirq); } static void gpiochip_set_irq_hooks(struct gpio_chip *gpiochip) { struct irq_chip *irqchip = gpiochip->irq.chip; if (!irqchip->irq_request_resources && !irqchip->irq_release_resources) { irqchip->irq_request_resources = gpiochip_irq_reqres; irqchip->irq_release_resources = gpiochip_irq_relres; } if (WARN_ON(gpiochip->irq.irq_enable)) return; /* Check if the irqchip already has this hook... */ if (irqchip->irq_enable == gpiochip_irq_enable) { /* * ...and if so, give a gentle warning that this is bad * practice. */ chip_info(gpiochip, "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n"); return; } gpiochip->irq.irq_enable = irqchip->irq_enable; gpiochip->irq.irq_disable = irqchip->irq_disable; irqchip->irq_enable = gpiochip_irq_enable; irqchip->irq_disable = gpiochip_irq_disable; } /** * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip * @gpiochip: the GPIO chip to add the IRQ chip to * @lock_key: lockdep class for IRQ lock * @request_key: lockdep class for IRQ request */ static int gpiochip_add_irqchip(struct gpio_chip *gpiochip, struct lock_class_key *lock_key, struct lock_class_key *request_key) { struct irq_chip *irqchip = gpiochip->irq.chip; const struct irq_domain_ops *ops; struct device_node *np; unsigned int type; unsigned int i; if (!irqchip) return 0; if (gpiochip->irq.parent_handler && gpiochip->can_sleep) { chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n"); return -EINVAL; } np = gpiochip->gpiodev->dev.of_node; type = gpiochip->irq.default_type; /* * Specifying a default trigger is a terrible idea if DT or ACPI is * used to configure the interrupts, as you may end up with * conflicting triggers. Tell the user, and reset to NONE. */ if (WARN(np && type != IRQ_TYPE_NONE, "%s: Ignoring %u default trigger\n", np->full_name, type)) type = IRQ_TYPE_NONE; if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) { acpi_handle_warn(ACPI_HANDLE(gpiochip->parent), "Ignoring %u default trigger\n", type); type = IRQ_TYPE_NONE; } gpiochip->to_irq = gpiochip_to_irq; gpiochip->irq.default_type = type; gpiochip->irq.lock_key = lock_key; gpiochip->irq.request_key = request_key; if (gpiochip->irq.domain_ops) ops = gpiochip->irq.domain_ops; else ops = &gpiochip_domain_ops; gpiochip->irq.domain = irq_domain_add_simple(np, gpiochip->ngpio, gpiochip->irq.first, ops, gpiochip); if (!gpiochip->irq.domain) return -EINVAL; if (gpiochip->irq.parent_handler) { void *data = gpiochip->irq.parent_handler_data ?: gpiochip; for (i = 0; i < gpiochip->irq.num_parents; i++) { /* * The parent IRQ chip is already using the chip_data * for this IRQ chip, so our callbacks simply use the * handler_data. */ irq_set_chained_handler_and_data(gpiochip->irq.parents[i], gpiochip->irq.parent_handler, data); } } gpiochip_set_irq_hooks(gpiochip); acpi_gpiochip_request_interrupts(gpiochip); return 0; } /** * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip * @gpiochip: the gpiochip to remove the irqchip from * * This is called only from gpiochip_remove() */ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) { struct irq_chip *irqchip = gpiochip->irq.chip; unsigned int offset; acpi_gpiochip_free_interrupts(gpiochip); if (irqchip && gpiochip->irq.parent_handler) { struct gpio_irq_chip *irq = &gpiochip->irq; unsigned int i; for (i = 0; i < irq->num_parents; i++) irq_set_chained_handler_and_data(irq->parents[i], NULL, NULL); } /* Remove all IRQ mappings and delete the domain */ if (gpiochip->irq.domain) { unsigned int irq; for (offset = 0; offset < gpiochip->ngpio; offset++) { if (!gpiochip_irqchip_irq_valid(gpiochip, offset)) continue; irq = irq_find_mapping(gpiochip->irq.domain, offset); irq_dispose_mapping(irq); } irq_domain_remove(gpiochip->irq.domain); } if (irqchip) { if (irqchip->irq_request_resources == gpiochip_irq_reqres) { irqchip->irq_request_resources = NULL; irqchip->irq_release_resources = NULL; } if (irqchip->irq_enable == gpiochip_irq_enable) { irqchip->irq_enable = gpiochip->irq.irq_enable; irqchip->irq_disable = gpiochip->irq.irq_disable; } } gpiochip->irq.irq_enable = NULL; gpiochip->irq.irq_disable = NULL; gpiochip->irq.chip = NULL; gpiochip_irqchip_free_valid_mask(gpiochip); } /** * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip * @gpiochip: the gpiochip to add the irqchip to * @irqchip: the irqchip to add to the gpiochip * @first_irq: if not dynamically assigned, the base (first) IRQ to * allocate gpiochip irqs from * @handler: the irq handler to use (often a predefined irq core function) * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE * to have the core avoid setting up any default type in the hardware. * @threaded: whether this irqchip uses a nested thread handler * @lock_key: lockdep class for IRQ lock * @request_key: lockdep class for IRQ request * * This function closely associates a certain irqchip with a certain * gpiochip, providing an irq domain to translate the local IRQs to * global irqs in the gpiolib core, and making sure that the gpiochip * is passed as chip data to all related functions. Driver callbacks * need to use gpiochip_get_data() to get their local state containers back * from the gpiochip passed as chip data. An irqdomain will be stored * in the gpiochip that shall be used by the driver to handle IRQ number * translation. The gpiochip will need to be initialized and registered * before calling this function. * * This function will handle two cell:ed simple IRQs and assumes all * the pins on the gpiochip can generate a unique IRQ. Everything else * need to be open coded. */ int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip, struct irq_chip *irqchip, unsigned int first_irq, irq_flow_handler_t handler, unsigned int type, bool threaded, struct lock_class_key *lock_key, struct lock_class_key *request_key) { struct device_node *of_node; if (!gpiochip || !irqchip) return -EINVAL; if (!gpiochip->parent) { pr_err("missing gpiochip .dev parent pointer\n"); return -EINVAL; } gpiochip->irq.threaded = threaded; of_node = gpiochip->parent->of_node; #ifdef CONFIG_OF_GPIO /* * If the gpiochip has an assigned OF node this takes precedence * FIXME: get rid of this and use gpiochip->parent->of_node * everywhere */ if (gpiochip->of_node) of_node = gpiochip->of_node; #endif /* * Specifying a default trigger is a terrible idea if DT or ACPI is * used to configure the interrupts, as you may end-up with * conflicting triggers. Tell the user, and reset to NONE. */ if (WARN(of_node && type != IRQ_TYPE_NONE, "%pOF: Ignoring %d default trigger\n", of_node, type)) type = IRQ_TYPE_NONE; if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) { acpi_handle_warn(ACPI_HANDLE(gpiochip->parent), "Ignoring %d default trigger\n", type); type = IRQ_TYPE_NONE; } gpiochip->irq.chip = irqchip; gpiochip->irq.handler = handler; gpiochip->irq.default_type = type; gpiochip->to_irq = gpiochip_to_irq; gpiochip->irq.lock_key = lock_key; gpiochip->irq.request_key = request_key; gpiochip->irq.domain = irq_domain_add_simple(of_node, gpiochip->ngpio, first_irq, &gpiochip_domain_ops, gpiochip); if (!gpiochip->irq.domain) { gpiochip->irq.chip = NULL; return -EINVAL; } gpiochip_set_irq_hooks(gpiochip); acpi_gpiochip_request_interrupts(gpiochip); return 0; } EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key); #else /* CONFIG_GPIOLIB_IRQCHIP */ static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip, struct lock_class_key *lock_key, struct lock_class_key *request_key) { return 0; } static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {} static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip) { return 0; } static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip) { } #endif /* CONFIG_GPIOLIB_IRQCHIP */ /** * gpiochip_generic_request() - request the gpio function for a pin * @chip: the gpiochip owning the GPIO * @offset: the offset of the GPIO to request for GPIO function */ int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset) { return pinctrl_gpio_request(chip->gpiodev->base + offset); } EXPORT_SYMBOL_GPL(gpiochip_generic_request); /** * gpiochip_generic_free() - free the gpio function from a pin * @chip: the gpiochip to request the gpio function for * @offset: the offset of the GPIO to free from GPIO function */ void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset) { pinctrl_gpio_free(chip->gpiodev->base + offset); } EXPORT_SYMBOL_GPL(gpiochip_generic_free); /** * gpiochip_generic_config() - apply configuration for a pin * @chip: the gpiochip owning the GPIO * @offset: the offset of the GPIO to apply the configuration * @config: the configuration to be applied */ int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset, unsigned long config) { return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config); } EXPORT_SYMBOL_GPL(gpiochip_generic_config); #ifdef CONFIG_PINCTRL /** * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping * @chip: the gpiochip to add the range for * @pctldev: the pin controller to map to * @gpio_offset: the start offset in the current gpio_chip number space * @pin_group: name of the pin group inside the pin controller * * Calling this function directly from a DeviceTree-supported * pinctrl driver is DEPRECATED. Please see Section 2.1 of * Documentation/devicetree/bindings/gpio/gpio.txt on how to * bind pinctrl and gpio drivers via the "gpio-ranges" property. */ int gpiochip_add_pingroup_range(struct gpio_chip *chip, struct pinctrl_dev *pctldev, unsigned int gpio_offset, const char *pin_group) { struct gpio_pin_range *pin_range; struct gpio_device *gdev = chip->gpiodev; int ret; pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); if (!pin_range) { chip_err(chip, "failed to allocate pin ranges\n"); return -ENOMEM; } /* Use local offset as range ID */ pin_range->range.id = gpio_offset; pin_range->range.gc = chip; pin_range->range.name = chip->label; pin_range->range.base = gdev->base + gpio_offset; pin_range->pctldev = pctldev; ret = pinctrl_get_group_pins(pctldev, pin_group, &pin_range->range.pins, &pin_range->range.npins); if (ret < 0) { kfree(pin_range); return ret; } pinctrl_add_gpio_range(pctldev, &pin_range->range); chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n", gpio_offset, gpio_offset + pin_range->range.npins - 1, pinctrl_dev_get_devname(pctldev), pin_group); list_add_tail(&pin_range->node, &gdev->pin_ranges); return 0; } EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); /** * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping * @chip: the gpiochip to add the range for * @pinctl_name: the dev_name() of the pin controller to map to * @gpio_offset: the start offset in the current gpio_chip number space * @pin_offset: the start offset in the pin controller number space * @npins: the number of pins from the offset of each pin space (GPIO and * pin controller) to accumulate in this range * * Returns: * 0 on success, or a negative error-code on failure. * * Calling this function directly from a DeviceTree-supported * pinctrl driver is DEPRECATED. Please see Section 2.1 of * Documentation/devicetree/bindings/gpio/gpio.txt on how to * bind pinctrl and gpio drivers via the "gpio-ranges" property. */ int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, unsigned int gpio_offset, unsigned int pin_offset, unsigned int npins) { struct gpio_pin_range *pin_range; struct gpio_device *gdev = chip->gpiodev; int ret; pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); if (!pin_range) { chip_err(chip, "failed to allocate pin ranges\n"); return -ENOMEM; } /* Use local offset as range ID */ pin_range->range.id = gpio_offset; pin_range->range.gc = chip; pin_range->range.name = chip->label; pin_range->range.base = gdev->base + gpio_offset; pin_range->range.pin_base = pin_offset; pin_range->range.npins = npins; pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, &pin_range->range); if (IS_ERR(pin_range->pctldev)) { ret = PTR_ERR(pin_range->pctldev); chip_err(chip, "could not create pin range\n"); kfree(pin_range); return ret; } chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n", gpio_offset, gpio_offset + npins - 1, pinctl_name, pin_offset, pin_offset + npins - 1); list_add_tail(&pin_range->node, &gdev->pin_ranges); return 0; } EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); /** * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings * @chip: the chip to remove all the mappings for */ void gpiochip_remove_pin_ranges(struct gpio_chip *chip) { struct gpio_pin_range *pin_range, *tmp; struct gpio_device *gdev = chip->gpiodev; list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) { list_del(&pin_range->node); pinctrl_remove_gpio_range(pin_range->pctldev, &pin_range->range); kfree(pin_range); } } EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); #endif /* CONFIG_PINCTRL */ /* These "optional" allocation calls help prevent drivers from stomping * on each other, and help provide better diagnostics in debugfs. * They're called even less than the "set direction" calls. */ static int gpiod_request_commit(struct gpio_desc *desc, const char *label) { struct gpio_chip *chip = desc->gdev->chip; int status; unsigned long flags; unsigned offset; spin_lock_irqsave(&gpio_lock, flags); /* NOTE: gpio_request() can be called in early boot, * before IRQs are enabled, for non-sleeping (SOC) GPIOs. */ if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { desc_set_label(desc, label ? : "?"); status = 0; } else { status = -EBUSY; goto done; } if (chip->request) { /* chip->request may sleep */ spin_unlock_irqrestore(&gpio_lock, flags); offset = gpio_chip_hwgpio(desc); if (gpiochip_line_is_valid(chip, offset)) status = chip->request(chip, offset); else status = -EINVAL; spin_lock_irqsave(&gpio_lock, flags); if (status < 0) { desc_set_label(desc, NULL); clear_bit(FLAG_REQUESTED, &desc->flags); goto done; } } if (chip->get_direction) { /* chip->get_direction may sleep */ spin_unlock_irqrestore(&gpio_lock, flags); gpiod_get_direction(desc); spin_lock_irqsave(&gpio_lock, flags); } done: spin_unlock_irqrestore(&gpio_lock, flags); return status; } /* * This descriptor validation needs to be inserted verbatim into each * function taking a descriptor, so we need to use a preprocessor * macro to avoid endless duplication. If the desc is NULL it is an * optional GPIO and calls should just bail out. */ static int validate_desc(const struct gpio_desc *desc, const char *func) { if (!desc) return 0; if (IS_ERR(desc)) { pr_warn("%s: invalid GPIO (errorpointer)\n", func); return PTR_ERR(desc); } if (!desc->gdev) { pr_warn("%s: invalid GPIO (no device)\n", func); return -EINVAL; } if (!desc->gdev->chip) { dev_warn(&desc->gdev->dev, "%s: backing chip is gone\n", func); return 0; } return 1; } #define VALIDATE_DESC(desc) do { \ int __valid = validate_desc(desc, __func__); \ if (__valid <= 0) \ return __valid; \ } while (0) #define VALIDATE_DESC_VOID(desc) do { \ int __valid = validate_desc(desc, __func__); \ if (__valid <= 0) \ return; \ } while (0) int gpiod_request(struct gpio_desc *desc, const char *label) { int status = -EPROBE_DEFER; struct gpio_device *gdev; VALIDATE_DESC(desc); gdev = desc->gdev; if (try_module_get(gdev->owner)) { status = gpiod_request_commit(desc, label); if (status < 0) module_put(gdev->owner); else get_device(&gdev->dev); } if (status) gpiod_dbg(desc, "%s: status %d\n", __func__, status); return status; } static bool gpiod_free_commit(struct gpio_desc *desc) { bool ret = false; unsigned long flags; struct gpio_chip *chip; might_sleep(); gpiod_unexport(desc); spin_lock_irqsave(&gpio_lock, flags); chip = desc->gdev->chip; if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) { if (chip->free) { spin_unlock_irqrestore(&gpio_lock, flags); might_sleep_if(chip->can_sleep); chip->free(chip, gpio_chip_hwgpio(desc)); spin_lock_irqsave(&gpio_lock, flags); } desc_set_label(desc, NULL); clear_bit(FLAG_ACTIVE_LOW, &desc->flags); clear_bit(FLAG_REQUESTED, &desc->flags); clear_bit(FLAG_OPEN_DRAIN, &desc->flags); clear_bit(FLAG_OPEN_SOURCE, &desc->flags); clear_bit(FLAG_IS_HOGGED, &desc->flags); ret = true; } spin_unlock_irqrestore(&gpio_lock, flags); return ret; } void gpiod_free(struct gpio_desc *desc) { if (desc && desc->gdev && gpiod_free_commit(desc)) { module_put(desc->gdev->owner); put_device(&desc->gdev->dev); } else { WARN_ON(extra_checks); } } /** * gpiochip_is_requested - return string iff signal was requested * @chip: controller managing the signal * @offset: of signal within controller's 0..(ngpio - 1) range * * Returns NULL if the GPIO is not currently requested, else a string. * The string returned is the label passed to gpio_request(); if none has been * passed it is a meaningless, non-NULL constant. * * This function is for use by GPIO controller drivers. The label can * help with diagnostics, and knowing that the signal is used as a GPIO * can help avoid accidentally multiplexing it to another controller. */ const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) { struct gpio_desc *desc; if (offset >= chip->ngpio) return NULL; desc = &chip->gpiodev->descs[offset]; if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) return NULL; return desc->label; } EXPORT_SYMBOL_GPL(gpiochip_is_requested); /** * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor * @chip: GPIO chip * @hwnum: hardware number of the GPIO for which to request the descriptor * @label: label for the GPIO * * Function allows GPIO chip drivers to request and use their own GPIO * descriptors via gpiolib API. Difference to gpiod_request() is that this * function will not increase reference count of the GPIO chip module. This * allows the GPIO chip module to be unloaded as needed (we assume that the * GPIO chip driver handles freeing the GPIOs it has requested). * * Returns: * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error * code on failure. */ struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum, const char *label) { struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum); int err; if (IS_ERR(desc)) { chip_err(chip, "failed to get GPIO descriptor\n"); return desc; } err = gpiod_request_commit(desc, label); if (err < 0) return ERR_PTR(err); return desc; } EXPORT_SYMBOL_GPL(gpiochip_request_own_desc); /** * gpiochip_free_own_desc - Free GPIO requested by the chip driver * @desc: GPIO descriptor to free * * Function frees the given GPIO requested previously with * gpiochip_request_own_desc(). */ void gpiochip_free_own_desc(struct gpio_desc *desc) { if (desc) gpiod_free_commit(desc); } EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); /* * Drivers MUST set GPIO direction before making get/set calls. In * some cases this is done in early boot, before IRQs are enabled. * * As a rule these aren't called more than once (except for drivers * using the open-drain emulation idiom) so these are natural places * to accumulate extra debugging checks. Note that we can't (yet) * rely on gpio_request() having been called beforehand. */ /** * gpiod_direction_input - set the GPIO direction to input * @desc: GPIO to set to input * * Set the direction of the passed GPIO to input, such as gpiod_get_value() can * be called safely on it. * * Return 0 in case of success, else an error code. */ int gpiod_direction_input(struct gpio_desc *desc) { struct gpio_chip *chip; int status = 0; VALIDATE_DESC(desc); chip = desc->gdev->chip; /* * It is legal to have no .get() and .direction_input() specified if * the chip is output-only, but you can't specify .direction_input() * and not support the .get() operation, that doesn't make sense. */ if (!chip->get && chip->direction_input) { gpiod_warn(desc, "%s: missing get() but have direction_input()\n", __func__); return -EIO; } /* * If we have a .direction_input() callback, things are simple, * just call it. Else we are some input-only chip so try to check the * direction (if .get_direction() is supported) else we silently * assume we are in input mode after this. */ if (chip->direction_input) { status = chip->direction_input(chip, gpio_chip_hwgpio(desc)); } else if (chip->get_direction && (chip->get_direction(chip, gpio_chip_hwgpio(desc)) != 1)) { gpiod_warn(desc, "%s: missing direction_input() operation and line is output\n", __func__); return -EIO; } if (status == 0) clear_bit(FLAG_IS_OUT, &desc->flags); trace_gpio_direction(desc_to_gpio(desc), 1, status); return status; } EXPORT_SYMBOL_GPL(gpiod_direction_input); static int gpio_set_drive_single_ended(struct gpio_chip *gc, unsigned offset, enum pin_config_param mode) { unsigned long config = { PIN_CONF_PACKED(mode, 0) }; return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP; } static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value) { struct gpio_chip *gc = desc->gdev->chip; int val = !!value; int ret = 0; /* * It's OK not to specify .direction_output() if the gpiochip is * output-only, but if there is then not even a .set() operation it * is pretty tricky to drive the output line. */ if (!gc->set && !gc->direction_output) { gpiod_warn(desc, "%s: missing set() and direction_output() operations\n", __func__); return -EIO; } if (gc->direction_output) { ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val); } else { /* Check that we are in output mode if we can */ if (gc->get_direction && gc->get_direction(gc, gpio_chip_hwgpio(desc))) { gpiod_warn(desc, "%s: missing direction_output() operation\n", __func__); return -EIO; } /* * If we can't actively set the direction, we are some * output-only chip, so just drive the output as desired. */ gc->set(gc, gpio_chip_hwgpio(desc), val); } if (!ret) set_bit(FLAG_IS_OUT, &desc->flags); trace_gpio_value(desc_to_gpio(desc), 0, val); trace_gpio_direction(desc_to_gpio(desc), 0, ret); return ret; } /** * gpiod_direction_output_raw - set the GPIO direction to output * @desc: GPIO to set to output * @value: initial output value of the GPIO * * Set the direction of the passed GPIO to output, such as gpiod_set_value() can * be called safely on it. The initial value of the output must be specified * as raw value on the physical line without regard for the ACTIVE_LOW status. * * Return 0 in case of success, else an error code. */ int gpiod_direction_output_raw(struct gpio_desc *desc, int value) { VALIDATE_DESC(desc); return gpiod_direction_output_raw_commit(desc, value); } EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); /** * gpiod_direction_output - set the GPIO direction to output * @desc: GPIO to set to output * @value: initial output value of the GPIO * * Set the direction of the passed GPIO to output, such as gpiod_set_value() can * be called safely on it. The initial value of the output must be specified * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into * account. * * Return 0 in case of success, else an error code. */ int gpiod_direction_output(struct gpio_desc *desc, int value) { struct gpio_chip *gc; int ret; VALIDATE_DESC(desc); if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) value = !value; else value = !!value; /* GPIOs used for enabled IRQs shall not be set as output */ if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) && test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) { gpiod_err(desc, "%s: tried to set a GPIO tied to an IRQ as output\n", __func__); return -EIO; } gc = desc->gdev->chip; if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) { /* First see if we can enable open drain in hardware */ ret = gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc), PIN_CONFIG_DRIVE_OPEN_DRAIN); if (!ret) goto set_output_value; /* Emulate open drain by not actively driving the line high */ if (value) return gpiod_direction_input(desc); } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) { ret = gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc), PIN_CONFIG_DRIVE_OPEN_SOURCE); if (!ret) goto set_output_value; /* Emulate open source by not actively driving the line low */ if (!value) return gpiod_direction_input(desc); } else { gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc), PIN_CONFIG_DRIVE_PUSH_PULL); } set_output_value: return gpiod_direction_output_raw_commit(desc, value); } EXPORT_SYMBOL_GPL(gpiod_direction_output); /** * gpiod_set_debounce - sets @debounce time for a GPIO * @desc: descriptor of the GPIO for which to set debounce time * @debounce: debounce time in microseconds * * Returns: * 0 on success, %-ENOTSUPP if the controller doesn't support setting the * debounce time. */ int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) { struct gpio_chip *chip; unsigned long config; VALIDATE_DESC(desc); chip = desc->gdev->chip; if (!chip->set || !chip->set_config) { gpiod_dbg(desc, "%s: missing set() or set_config() operations\n", __func__); return -ENOTSUPP; } config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce); return chip->set_config(chip, gpio_chip_hwgpio(desc), config); } EXPORT_SYMBOL_GPL(gpiod_set_debounce); /** * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset * @desc: descriptor of the GPIO for which to configure persistence * @transitory: True to lose state on suspend or reset, false for persistence * * Returns: * 0 on success, otherwise a negative error code. */ int gpiod_set_transitory(struct gpio_desc *desc, bool transitory) { struct gpio_chip *chip; unsigned long packed; int gpio; int rc; VALIDATE_DESC(desc); /* * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for * persistence state. */ if (transitory) set_bit(FLAG_TRANSITORY, &desc->flags); else clear_bit(FLAG_TRANSITORY, &desc->flags); /* If the driver supports it, set the persistence state now */ chip = desc->gdev->chip; if (!chip->set_config) return 0; packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE, !transitory); gpio = gpio_chip_hwgpio(desc); rc = chip->set_config(chip, gpio, packed); if (rc == -ENOTSUPP) { dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n", gpio); return 0; } return rc; } EXPORT_SYMBOL_GPL(gpiod_set_transitory); /** * gpiod_is_active_low - test whether a GPIO is active-low or not * @desc: the gpio descriptor to test * * Returns 1 if the GPIO is active-low, 0 otherwise. */ int gpiod_is_active_low(const struct gpio_desc *desc) { VALIDATE_DESC(desc); return test_bit(FLAG_ACTIVE_LOW, &desc->flags); } EXPORT_SYMBOL_GPL(gpiod_is_active_low); /* I/O calls are only valid after configuration completed; the relevant * "is this a valid GPIO" error checks should already have been done. * * "Get" operations are often inlinable as reading a pin value register, * and masking the relevant bit in that register. * * When "set" operations are inlinable, they involve writing that mask to * one register to set a low value, or a different register to set it high. * Otherwise locking is needed, so there may be little value to inlining. * *------------------------------------------------------------------------ * * IMPORTANT!!! The hot paths -- get/set value -- assume that callers * have requested the GPIO. That can include implicit requesting by * a direction setting call. Marking a gpio as requested locks its chip * in memory, guaranteeing that these table lookups need no more locking * and that gpiochip_remove() will fail. * * REVISIT when debugging, consider adding some instrumentation to ensure * that the GPIO was actually requested. */ static int gpiod_get_raw_value_commit(const struct gpio_desc *desc) { struct gpio_chip *chip; int offset; int value; chip = desc->gdev->chip; offset = gpio_chip_hwgpio(desc); value = chip->get ? chip->get(chip, offset) : -EIO; value = value < 0 ? value : !!value; trace_gpio_value(desc_to_gpio(desc), 1, value); return value; } static int gpio_chip_get_multiple(struct gpio_chip *chip, unsigned long *mask, unsigned long *bits) { if (chip->get_multiple) { return chip->get_multiple(chip, mask, bits); } else if (chip->get) { int i, value; for_each_set_bit(i, mask, chip->ngpio) { value = chip->get(chip, i); if (value < 0) return value; __assign_bit(i, bits, value); } return 0; } return -EIO; } int gpiod_get_array_value_complex(bool raw, bool can_sleep, unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { int err, i = 0; /* * Validate array_info against desc_array and its size. * It should immediately follow desc_array if both * have been obtained from the same gpiod_get_array() call. */ if (array_info && array_info->desc == desc_array && array_size <= array_info->size && (void *)array_info == desc_array + array_info->size) { if (!can_sleep) WARN_ON(array_info->chip->can_sleep); err = gpio_chip_get_multiple(array_info->chip, array_info->get_mask, value_bitmap); if (err) return err; if (!raw && !bitmap_empty(array_info->invert_mask, array_size)) bitmap_xor(value_bitmap, value_bitmap, array_info->invert_mask, array_size); if (bitmap_full(array_info->get_mask, array_size)) return 0; i = find_first_zero_bit(array_info->get_mask, array_size); } else { array_info = NULL; } while (i < array_size) { struct gpio_chip *chip = desc_array[i]->gdev->chip; unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)]; unsigned long *mask, *bits; int first, j, ret; if (likely(chip->ngpio <= FASTPATH_NGPIO)) { mask = fastpath; } else { mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio), sizeof(*mask), can_sleep ? GFP_KERNEL : GFP_ATOMIC); if (!mask) return -ENOMEM; } bits = mask + BITS_TO_LONGS(chip->ngpio); bitmap_zero(mask, chip->ngpio); if (!can_sleep) WARN_ON(chip->can_sleep); /* collect all inputs belonging to the same chip */ first = i; do { const struct gpio_desc *desc = desc_array[i]; int hwgpio = gpio_chip_hwgpio(desc); __set_bit(hwgpio, mask); i++; if (array_info) i = find_next_zero_bit(array_info->get_mask, array_size, i); } while ((i < array_size) && (desc_array[i]->gdev->chip == chip)); ret = gpio_chip_get_multiple(chip, mask, bits); if (ret) { if (mask != fastpath) kfree(mask); return ret; } for (j = first; j < i; ) { const struct gpio_desc *desc = desc_array[j]; int hwgpio = gpio_chip_hwgpio(desc); int value = test_bit(hwgpio, bits); if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags)) value = !value; __assign_bit(j, value_bitmap, value); trace_gpio_value(desc_to_gpio(desc), 1, value); j++; if (array_info) j = find_next_zero_bit(array_info->get_mask, i, j); } if (mask != fastpath) kfree(mask); } return 0; } /** * gpiod_get_raw_value() - return a gpio's raw value * @desc: gpio whose value will be returned * * Return the GPIO's raw value, i.e. the value of the physical line disregarding * its ACTIVE_LOW status, or negative errno on failure. * * This function should be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. */ int gpiod_get_raw_value(const struct gpio_desc *desc) { VALIDATE_DESC(desc); /* Should be using gpio_get_value_cansleep() */ WARN_ON(desc->gdev->chip->can_sleep); return gpiod_get_raw_value_commit(desc); } EXPORT_SYMBOL_GPL(gpiod_get_raw_value); /** * gpiod_get_value() - return a gpio's value * @desc: gpio whose value will be returned * * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into * account, or negative errno on failure. * * This function should be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. */ int gpiod_get_value(const struct gpio_desc *desc) { int value; VALIDATE_DESC(desc); /* Should be using gpio_get_value_cansleep() */ WARN_ON(desc->gdev->chip->can_sleep); value = gpiod_get_raw_value_commit(desc); if (value < 0) return value; if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) value = !value; return value; } EXPORT_SYMBOL_GPL(gpiod_get_value); /** * gpiod_get_raw_array_value() - read raw values from an array of GPIOs * @array_size: number of elements in the descriptor array / value bitmap * @desc_array: array of GPIO descriptors whose values will be read * @array_info: information on applicability of fast bitmap processing path * @value_bitmap: bitmap to store the read values * * Read the raw values of the GPIOs, i.e. the values of the physical lines * without regard for their ACTIVE_LOW status. Return 0 in case of success, * else an error code. * * This function should be called from contexts where we cannot sleep, * and it will complain if the GPIO chip functions potentially sleep. */ int gpiod_get_raw_array_value(unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { if (!desc_array) return -EINVAL; return gpiod_get_array_value_complex(true, false, array_size, desc_array, array_info, value_bitmap); } EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value); /** * gpiod_get_array_value() - read values from an array of GPIOs * @array_size: number of elements in the descriptor array / value bitmap * @desc_array: array of GPIO descriptors whose values will be read * @array_info: information on applicability of fast bitmap processing path * @value_bitmap: bitmap to store the read values * * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status * into account. Return 0 in case of success, else an error code. * * This function should be called from contexts where we cannot sleep, * and it will complain if the GPIO chip functions potentially sleep. */ int gpiod_get_array_value(unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { if (!desc_array) return -EINVAL; return gpiod_get_array_value_complex(false, false, array_size, desc_array, array_info, value_bitmap); } EXPORT_SYMBOL_GPL(gpiod_get_array_value); /* * gpio_set_open_drain_value_commit() - Set the open drain gpio's value. * @desc: gpio descriptor whose state need to be set. * @value: Non-zero for setting it HIGH otherwise it will set to LOW. */ static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value) { int err = 0; struct gpio_chip *chip = desc->gdev->chip; int offset = gpio_chip_hwgpio(desc); if (value) { err = chip->direction_input(chip, offset); if (!err) clear_bit(FLAG_IS_OUT, &desc->flags); } else { err = chip->direction_output(chip, offset, 0); if (!err) set_bit(FLAG_IS_OUT, &desc->flags); } trace_gpio_direction(desc_to_gpio(desc), value, err); if (err < 0) gpiod_err(desc, "%s: Error in set_value for open drain err %d\n", __func__, err); } /* * _gpio_set_open_source_value() - Set the open source gpio's value. * @desc: gpio descriptor whose state need to be set. * @value: Non-zero for setting it HIGH otherwise it will set to LOW. */ static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value) { int err = 0; struct gpio_chip *chip = desc->gdev->chip; int offset = gpio_chip_hwgpio(desc); if (value) { err = chip->direction_output(chip, offset, 1); if (!err) set_bit(FLAG_IS_OUT, &desc->flags); } else { err = chip->direction_input(chip, offset); if (!err) clear_bit(FLAG_IS_OUT, &desc->flags); } trace_gpio_direction(desc_to_gpio(desc), !value, err); if (err < 0) gpiod_err(desc, "%s: Error in set_value for open source err %d\n", __func__, err); } static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value) { struct gpio_chip *chip; chip = desc->gdev->chip; trace_gpio_value(desc_to_gpio(desc), 0, value); chip->set(chip, gpio_chip_hwgpio(desc), value); } /* * set multiple outputs on the same chip; * use the chip's set_multiple function if available; * otherwise set the outputs sequentially; * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word * defines which outputs are to be changed * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word * defines the values the outputs specified by mask are to be set to */ static void gpio_chip_set_multiple(struct gpio_chip *chip, unsigned long *mask, unsigned long *bits) { if (chip->set_multiple) { chip->set_multiple(chip, mask, bits); } else { unsigned int i; /* set outputs if the corresponding mask bit is set */ for_each_set_bit(i, mask, chip->ngpio) chip->set(chip, i, test_bit(i, bits)); } } int gpiod_set_array_value_complex(bool raw, bool can_sleep, unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { int i = 0; /* * Validate array_info against desc_array and its size. * It should immediately follow desc_array if both * have been obtained from the same gpiod_get_array() call. */ if (array_info && array_info->desc == desc_array && array_size <= array_info->size && (void *)array_info == desc_array + array_info->size) { if (!can_sleep) WARN_ON(array_info->chip->can_sleep); if (!raw && !bitmap_empty(array_info->invert_mask, array_size)) bitmap_xor(value_bitmap, value_bitmap, array_info->invert_mask, array_size); gpio_chip_set_multiple(array_info->chip, array_info->set_mask, value_bitmap); if (bitmap_full(array_info->set_mask, array_size)) return 0; i = find_first_zero_bit(array_info->set_mask, array_size); } else { array_info = NULL; } while (i < array_size) { struct gpio_chip *chip = desc_array[i]->gdev->chip; unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)]; unsigned long *mask, *bits; int count = 0; if (likely(chip->ngpio <= FASTPATH_NGPIO)) { mask = fastpath; } else { mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio), sizeof(*mask), can_sleep ? GFP_KERNEL : GFP_ATOMIC); if (!mask) return -ENOMEM; } bits = mask + BITS_TO_LONGS(chip->ngpio); bitmap_zero(mask, chip->ngpio); if (!can_sleep) WARN_ON(chip->can_sleep); do { struct gpio_desc *desc = desc_array[i]; int hwgpio = gpio_chip_hwgpio(desc); int value = test_bit(i, value_bitmap); /* * Pins applicable for fast input but not for * fast output processing may have been already * inverted inside the fast path, skip them. */ if (!raw && !(array_info && test_bit(i, array_info->invert_mask)) && test_bit(FLAG_ACTIVE_LOW, &desc->flags)) value = !value; trace_gpio_value(desc_to_gpio(desc), 0, value); /* * collect all normal outputs belonging to the same chip * open drain and open source outputs are set individually */ if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) { gpio_set_open_drain_value_commit(desc, value); } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) { gpio_set_open_source_value_commit(desc, value); } else { __set_bit(hwgpio, mask); if (value) __set_bit(hwgpio, bits); else __clear_bit(hwgpio, bits); count++; } i++; if (array_info) i = find_next_zero_bit(array_info->set_mask, array_size, i); } while ((i < array_size) && (desc_array[i]->gdev->chip == chip)); /* push collected bits to outputs */ if (count != 0) gpio_chip_set_multiple(chip, mask, bits); if (mask != fastpath) kfree(mask); } return 0; } /** * gpiod_set_raw_value() - assign a gpio's raw value * @desc: gpio whose value will be assigned * @value: value to assign * * Set the raw value of the GPIO, i.e. the value of its physical line without * regard for its ACTIVE_LOW status. * * This function should be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. */ void gpiod_set_raw_value(struct gpio_desc *desc, int value) { VALIDATE_DESC_VOID(desc); /* Should be using gpiod_set_value_cansleep() */ WARN_ON(desc->gdev->chip->can_sleep); gpiod_set_raw_value_commit(desc, value); } EXPORT_SYMBOL_GPL(gpiod_set_raw_value); /** * gpiod_set_value_nocheck() - set a GPIO line value without checking * @desc: the descriptor to set the value on * @value: value to set * * This sets the value of a GPIO line backing a descriptor, applying * different semantic quirks like active low and open drain/source * handling. */ static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value) { if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) value = !value; if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) gpio_set_open_drain_value_commit(desc, value); else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) gpio_set_open_source_value_commit(desc, value); else gpiod_set_raw_value_commit(desc, value); } /** * gpiod_set_value() - assign a gpio's value * @desc: gpio whose value will be assigned * @value: value to assign * * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW, * OPEN_DRAIN and OPEN_SOURCE flags into account. * * This function should be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. */ void gpiod_set_value(struct gpio_desc *desc, int value) { VALIDATE_DESC_VOID(desc); WARN_ON(desc->gdev->chip->can_sleep); gpiod_set_value_nocheck(desc, value); } EXPORT_SYMBOL_GPL(gpiod_set_value); /** * gpiod_set_raw_array_value() - assign values to an array of GPIOs * @array_size: number of elements in the descriptor array / value bitmap * @desc_array: array of GPIO descriptors whose values will be assigned * @array_info: information on applicability of fast bitmap processing path * @value_bitmap: bitmap of values to assign * * Set the raw values of the GPIOs, i.e. the values of the physical lines * without regard for their ACTIVE_LOW status. * * This function should be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. */ int gpiod_set_raw_array_value(unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { if (!desc_array) return -EINVAL; return gpiod_set_array_value_complex(true, false, array_size, desc_array, array_info, value_bitmap); } EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value); /** * gpiod_set_array_value() - assign values to an array of GPIOs * @array_size: number of elements in the descriptor array / value bitmap * @desc_array: array of GPIO descriptors whose values will be assigned * @array_info: information on applicability of fast bitmap processing path * @value_bitmap: bitmap of values to assign * * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status * into account. * * This function should be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. */ int gpiod_set_array_value(unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { if (!desc_array) return -EINVAL; return gpiod_set_array_value_complex(false, false, array_size, desc_array, array_info, value_bitmap); } EXPORT_SYMBOL_GPL(gpiod_set_array_value); /** * gpiod_cansleep() - report whether gpio value access may sleep * @desc: gpio to check * */ int gpiod_cansleep(const struct gpio_desc *desc) { VALIDATE_DESC(desc); return desc->gdev->chip->can_sleep; } EXPORT_SYMBOL_GPL(gpiod_cansleep); /** * gpiod_set_consumer_name() - set the consumer name for the descriptor * @desc: gpio to set the consumer name on * @name: the new consumer name */ void gpiod_set_consumer_name(struct gpio_desc *desc, const char *name) { VALIDATE_DESC_VOID(desc); /* Just overwrite whatever the previous name was */ desc->label = name; } EXPORT_SYMBOL_GPL(gpiod_set_consumer_name); /** * gpiod_to_irq() - return the IRQ corresponding to a GPIO * @desc: gpio whose IRQ will be returned (already requested) * * Return the IRQ corresponding to the passed GPIO, or an error code in case of * error. */ int gpiod_to_irq(const struct gpio_desc *desc) { struct gpio_chip *chip; int offset; /* * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics * requires this function to not return zero on an invalid descriptor * but rather a negative error number. */ if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip) return -EINVAL; chip = desc->gdev->chip; offset = gpio_chip_hwgpio(desc); if (chip->to_irq) { int retirq = chip->to_irq(chip, offset); /* Zero means NO_IRQ */ if (!retirq) return -ENXIO; return retirq; } return -ENXIO; } EXPORT_SYMBOL_GPL(gpiod_to_irq); /** * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ * @chip: the chip the GPIO to lock belongs to * @offset: the offset of the GPIO to lock as IRQ * * This is used directly by GPIO drivers that want to lock down * a certain GPIO line to be used for IRQs. */ int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset) { struct gpio_desc *desc; desc = gpiochip_get_desc(chip, offset); if (IS_ERR(desc)) return PTR_ERR(desc); /* * If it's fast: flush the direction setting if something changed * behind our back */ if (!chip->can_sleep && chip->get_direction) { int dir = gpiod_get_direction(desc); if (dir < 0) { chip_err(chip, "%s: cannot get GPIO direction\n", __func__); return dir; } } if (test_bit(FLAG_IS_OUT, &desc->flags)) { chip_err(chip, "%s: tried to flag a GPIO set as output for IRQ\n", __func__); return -EIO; } set_bit(FLAG_USED_AS_IRQ, &desc->flags); set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); /* * If the consumer has not set up a label (such as when the * IRQ is referenced from .to_irq()) we set up a label here * so it is clear this is used as an interrupt. */ if (!desc->label) desc_set_label(desc, "interrupt"); return 0; } EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq); /** * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ * @chip: the chip the GPIO to lock belongs to * @offset: the offset of the GPIO to lock as IRQ * * This is used directly by GPIO drivers that want to indicate * that a certain GPIO is no longer used exclusively for IRQ. */ void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) { struct gpio_desc *desc; desc = gpiochip_get_desc(chip, offset); if (IS_ERR(desc)) return; clear_bit(FLAG_USED_AS_IRQ, &desc->flags); clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); /* If we only had this marking, erase it */ if (desc->label && !strcmp(desc->label, "interrupt")) desc_set_label(desc, NULL); } EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq); void gpiochip_disable_irq(struct gpio_chip *chip, unsigned int offset) { struct gpio_desc *desc = gpiochip_get_desc(chip, offset); if (!IS_ERR(desc) && !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); } EXPORT_SYMBOL_GPL(gpiochip_disable_irq); void gpiochip_enable_irq(struct gpio_chip *chip, unsigned int offset) { struct gpio_desc *desc = gpiochip_get_desc(chip, offset); if (!IS_ERR(desc) && !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) { WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags)); set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); } } EXPORT_SYMBOL_GPL(gpiochip_enable_irq); bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset) { if (offset >= chip->ngpio) return false; return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags); } EXPORT_SYMBOL_GPL(gpiochip_line_is_irq); int gpiochip_reqres_irq(struct gpio_chip *chip, unsigned int offset) { int ret; if (!try_module_get(chip->gpiodev->owner)) return -ENODEV; ret = gpiochip_lock_as_irq(chip, offset); if (ret) { chip_err(chip, "unable to lock HW IRQ %u for IRQ\n", offset); module_put(chip->gpiodev->owner); return ret; } return 0; } EXPORT_SYMBOL_GPL(gpiochip_reqres_irq); void gpiochip_relres_irq(struct gpio_chip *chip, unsigned int offset) { gpiochip_unlock_as_irq(chip, offset); module_put(chip->gpiodev->owner); } EXPORT_SYMBOL_GPL(gpiochip_relres_irq); bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset) { if (offset >= chip->ngpio) return false; return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags); } EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain); bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset) { if (offset >= chip->ngpio) return false; return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags); } EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source); bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset) { if (offset >= chip->ngpio) return false; return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags); } EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent); /** * gpiod_get_raw_value_cansleep() - return a gpio's raw value * @desc: gpio whose value will be returned * * Return the GPIO's raw value, i.e. the value of the physical line disregarding * its ACTIVE_LOW status, or negative errno on failure. * * This function is to be called from contexts that can sleep. */ int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) { might_sleep_if(extra_checks); VALIDATE_DESC(desc); return gpiod_get_raw_value_commit(desc); } EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); /** * gpiod_get_value_cansleep() - return a gpio's value * @desc: gpio whose value will be returned * * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into * account, or negative errno on failure. * * This function is to be called from contexts that can sleep. */ int gpiod_get_value_cansleep(const struct gpio_desc *desc) { int value; might_sleep_if(extra_checks); VALIDATE_DESC(desc); value = gpiod_get_raw_value_commit(desc); if (value < 0) return value; if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) value = !value; return value; } EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); /** * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs * @array_size: number of elements in the descriptor array / value bitmap * @desc_array: array of GPIO descriptors whose values will be read * @array_info: information on applicability of fast bitmap processing path * @value_bitmap: bitmap to store the read values * * Read the raw values of the GPIOs, i.e. the values of the physical lines * without regard for their ACTIVE_LOW status. Return 0 in case of success, * else an error code. * * This function is to be called from contexts that can sleep. */ int gpiod_get_raw_array_value_cansleep(unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { might_sleep_if(extra_checks); if (!desc_array) return -EINVAL; return gpiod_get_array_value_complex(true, true, array_size, desc_array, array_info, value_bitmap); } EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep); /** * gpiod_get_array_value_cansleep() - read values from an array of GPIOs * @array_size: number of elements in the descriptor array / value bitmap * @desc_array: array of GPIO descriptors whose values will be read * @array_info: information on applicability of fast bitmap processing path * @value_bitmap: bitmap to store the read values * * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status * into account. Return 0 in case of success, else an error code. * * This function is to be called from contexts that can sleep. */ int gpiod_get_array_value_cansleep(unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { might_sleep_if(extra_checks); if (!desc_array) return -EINVAL; return gpiod_get_array_value_complex(false, true, array_size, desc_array, array_info, value_bitmap); } EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep); /** * gpiod_set_raw_value_cansleep() - assign a gpio's raw value * @desc: gpio whose value will be assigned * @value: value to assign * * Set the raw value of the GPIO, i.e. the value of its physical line without * regard for its ACTIVE_LOW status. * * This function is to be called from contexts that can sleep. */ void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) { might_sleep_if(extra_checks); VALIDATE_DESC_VOID(desc); gpiod_set_raw_value_commit(desc, value); } EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); /** * gpiod_set_value_cansleep() - assign a gpio's value * @desc: gpio whose value will be assigned * @value: value to assign * * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into * account * * This function is to be called from contexts that can sleep. */ void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) { might_sleep_if(extra_checks); VALIDATE_DESC_VOID(desc); gpiod_set_value_nocheck(desc, value); } EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); /** * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs * @array_size: number of elements in the descriptor array / value bitmap * @desc_array: array of GPIO descriptors whose values will be assigned * @array_info: information on applicability of fast bitmap processing path * @value_bitmap: bitmap of values to assign * * Set the raw values of the GPIOs, i.e. the values of the physical lines * without regard for their ACTIVE_LOW status. * * This function is to be called from contexts that can sleep. */ int gpiod_set_raw_array_value_cansleep(unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { might_sleep_if(extra_checks); if (!desc_array) return -EINVAL; return gpiod_set_array_value_complex(true, true, array_size, desc_array, array_info, value_bitmap); } EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep); /** * gpiod_add_lookup_tables() - register GPIO device consumers * @tables: list of tables of consumers to register * @n: number of tables in the list */ void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) { unsigned int i; mutex_lock(&gpio_lookup_lock); for (i = 0; i < n; i++) list_add_tail(&tables[i]->list, &gpio_lookup_list); mutex_unlock(&gpio_lookup_lock); } /** * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs * @array_size: number of elements in the descriptor array / value bitmap * @desc_array: array of GPIO descriptors whose values will be assigned * @array_info: information on applicability of fast bitmap processing path * @value_bitmap: bitmap of values to assign * * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status * into account. * * This function is to be called from contexts that can sleep. */ int gpiod_set_array_value_cansleep(unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { might_sleep_if(extra_checks); if (!desc_array) return -EINVAL; return gpiod_set_array_value_complex(false, true, array_size, desc_array, array_info, value_bitmap); } EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep); /** * gpiod_add_lookup_table() - register GPIO device consumers * @table: table of consumers to register */ void gpiod_add_lookup_table(struct gpiod_lookup_table *table) { mutex_lock(&gpio_lookup_lock); list_add_tail(&table->list, &gpio_lookup_list); mutex_unlock(&gpio_lookup_lock); } EXPORT_SYMBOL_GPL(gpiod_add_lookup_table); /** * gpiod_remove_lookup_table() - unregister GPIO device consumers * @table: table of consumers to unregister */ void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) { mutex_lock(&gpio_lookup_lock); list_del(&table->list); mutex_unlock(&gpio_lookup_lock); } EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table); /** * gpiod_add_hogs() - register a set of GPIO hogs from machine code * @hogs: table of gpio hog entries with a zeroed sentinel at the end */ void gpiod_add_hogs(struct gpiod_hog *hogs) { struct gpio_chip *chip; struct gpiod_hog *hog; mutex_lock(&gpio_machine_hogs_mutex); for (hog = &hogs[0]; hog->chip_label; hog++) { list_add_tail(&hog->list, &gpio_machine_hogs); /* * The chip may have been registered earlier, so check if it * exists and, if so, try to hog the line now. */ chip = find_chip_by_name(hog->chip_label); if (chip) gpiochip_machine_hog(chip, hog); } mutex_unlock(&gpio_machine_hogs_mutex); } EXPORT_SYMBOL_GPL(gpiod_add_hogs); static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) { const char *dev_id = dev ? dev_name(dev) : NULL; struct gpiod_lookup_table *table; mutex_lock(&gpio_lookup_lock); list_for_each_entry(table, &gpio_lookup_list, list) { if (table->dev_id && dev_id) { /* * Valid strings on both ends, must be identical to have * a match */ if (!strcmp(table->dev_id, dev_id)) goto found; } else { /* * One of the pointers is NULL, so both must be to have * a match */ if (dev_id == table->dev_id) goto found; } } table = NULL; found: mutex_unlock(&gpio_lookup_lock); return table; } static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, unsigned int idx, enum gpio_lookup_flags *flags) { struct gpio_desc *desc = ERR_PTR(-ENOENT); struct gpiod_lookup_table *table; struct gpiod_lookup *p; table = gpiod_find_lookup_table(dev); if (!table) return desc; for (p = &table->table[0]; p->chip_label; p++) { struct gpio_chip *chip; /* idx must always match exactly */ if (p->idx != idx) continue; /* If the lookup entry has a con_id, require exact match */ if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) continue; chip = find_chip_by_name(p->chip_label); if (!chip) { /* * As the lookup table indicates a chip with * p->chip_label should exist, assume it may * still appear later and let the interested * consumer be probed again or let the Deferred * Probe infrastructure handle the error. */ dev_warn(dev, "cannot find GPIO chip %s, deferring\n", p->chip_label); return ERR_PTR(-EPROBE_DEFER); } if (chip->ngpio <= p->chip_hwnum) { dev_err(dev, "requested GPIO %d is out of range [0..%d] for chip %s\n", idx, chip->ngpio, chip->label); return ERR_PTR(-EINVAL); } desc = gpiochip_get_desc(chip, p->chip_hwnum); *flags = p->flags; return desc; } return desc; } static int dt_gpio_count(struct device *dev, const char *con_id) { int ret; char propname[32]; unsigned int i; for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { if (con_id) snprintf(propname, sizeof(propname), "%s-%s", con_id, gpio_suffixes[i]); else snprintf(propname, sizeof(propname), "%s", gpio_suffixes[i]); ret = of_gpio_named_count(dev->of_node, propname); if (ret > 0) break; } return ret ? ret : -ENOENT; } static int platform_gpio_count(struct device *dev, const char *con_id) { struct gpiod_lookup_table *table; struct gpiod_lookup *p; unsigned int count = 0; table = gpiod_find_lookup_table(dev); if (!table) return -ENOENT; for (p = &table->table[0]; p->chip_label; p++) { if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) || (!con_id && !p->con_id)) count++; } if (!count) return -ENOENT; return count; } /** * gpiod_count - return the number of GPIOs associated with a device / function * or -ENOENT if no GPIO has been assigned to the requested function * @dev: GPIO consumer, can be NULL for system-global GPIOs * @con_id: function within the GPIO consumer */ int gpiod_count(struct device *dev, const char *con_id) { int count = -ENOENT; if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) count = dt_gpio_count(dev, con_id); else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) count = acpi_gpio_count(dev, con_id); if (count < 0) count = platform_gpio_count(dev, con_id); return count; } EXPORT_SYMBOL_GPL(gpiod_count); /** * gpiod_get - obtain a GPIO for a given GPIO function * @dev: GPIO consumer, can be NULL for system-global GPIOs * @con_id: function within the GPIO consumer * @flags: optional GPIO initialization flags * * Return the GPIO descriptor corresponding to the function con_id of device * dev, -ENOENT if no GPIO has been assigned to the requested function, or * another IS_ERR() code if an error occurred while trying to acquire the GPIO. */ struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id, enum gpiod_flags flags) { return gpiod_get_index(dev, con_id, 0, flags); } EXPORT_SYMBOL_GPL(gpiod_get); /** * gpiod_get_optional - obtain an optional GPIO for a given GPIO function * @dev: GPIO consumer, can be NULL for system-global GPIOs * @con_id: function within the GPIO consumer * @flags: optional GPIO initialization flags * * This is equivalent to gpiod_get(), except that when no GPIO was assigned to * the requested function it will return NULL. This is convenient for drivers * that need to handle optional GPIOs. */ struct gpio_desc *__must_check gpiod_get_optional(struct device *dev, const char *con_id, enum gpiod_flags flags) { return gpiod_get_index_optional(dev, con_id, 0, flags); } EXPORT_SYMBOL_GPL(gpiod_get_optional); /** * gpiod_configure_flags - helper function to configure a given GPIO * @desc: gpio whose value will be assigned * @con_id: function within the GPIO consumer * @lflags: gpio_lookup_flags - returned from of_find_gpio() or * of_get_gpio_hog() * @dflags: gpiod_flags - optional GPIO initialization flags * * Return 0 on success, -ENOENT if no GPIO has been assigned to the * requested function and/or index, or another IS_ERR() code if an error * occurred while trying to acquire the GPIO. */ int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, unsigned long lflags, enum gpiod_flags dflags) { int status; if (lflags & GPIO_ACTIVE_LOW) set_bit(FLAG_ACTIVE_LOW, &desc->flags); if (lflags & GPIO_OPEN_DRAIN) set_bit(FLAG_OPEN_DRAIN, &desc->flags); else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) { /* * This enforces open drain mode from the consumer side. * This is necessary for some busses like I2C, but the lookup * should *REALLY* have specified them as open drain in the * first place, so print a little warning here. */ set_bit(FLAG_OPEN_DRAIN, &desc->flags); gpiod_warn(desc, "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n"); } if (lflags & GPIO_OPEN_SOURCE) set_bit(FLAG_OPEN_SOURCE, &desc->flags); status = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY)); if (status < 0) return status; /* No particular flag request, return here... */ if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) { pr_debug("no flags found for %s\n", con_id); return 0; } /* Process flags */ if (dflags & GPIOD_FLAGS_BIT_DIR_OUT) status = gpiod_direction_output(desc, !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL)); else status = gpiod_direction_input(desc); return status; } /** * gpiod_get_index - obtain a GPIO from a multi-index GPIO function * @dev: GPIO consumer, can be NULL for system-global GPIOs * @con_id: function within the GPIO consumer * @idx: index of the GPIO to obtain in the consumer * @flags: optional GPIO initialization flags * * This variant of gpiod_get() allows to access GPIOs other than the first * defined one for functions that define several GPIOs. * * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the * requested function and/or index, or another IS_ERR() code if an error * occurred while trying to acquire the GPIO. */ struct gpio_desc *__must_check gpiod_get_index(struct device *dev, const char *con_id, unsigned int idx, enum gpiod_flags flags) { struct gpio_desc *desc = NULL; int status; enum gpio_lookup_flags lookupflags = 0; /* Maybe we have a device name, maybe not */ const char *devname = dev ? dev_name(dev) : "?"; dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); if (dev) { /* Using device tree? */ if (IS_ENABLED(CONFIG_OF) && dev->of_node) { dev_dbg(dev, "using device tree for GPIO lookup\n"); desc = of_find_gpio(dev, con_id, idx, &lookupflags); } else if (ACPI_COMPANION(dev)) { dev_dbg(dev, "using ACPI for GPIO lookup\n"); desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags); } } /* * Either we are not using DT or ACPI, or their lookup did not return * a result. In that case, use platform lookup as a fallback. */ if (!desc || desc == ERR_PTR(-ENOENT)) { dev_dbg(dev, "using lookup tables for GPIO lookup\n"); desc = gpiod_find(dev, con_id, idx, &lookupflags); } if (IS_ERR(desc)) { dev_dbg(dev, "No GPIO consumer %s found\n", con_id); return desc; } /* * If a connection label was passed use that, else attempt to use * the device name as label */ status = gpiod_request(desc, con_id ? con_id : devname); if (status < 0) { if (status == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) { /* * This happens when there are several consumers for * the same GPIO line: we just return here without * further initialization. It is a bit if a hack. * This is necessary to support fixed regulators. * * FIXME: Make this more sane and safe. */ dev_info(dev, "nonexclusive access to GPIO for %s\n", con_id ? con_id : devname); return desc; } else { return ERR_PTR(status); } } status = gpiod_configure_flags(desc, con_id, lookupflags, flags); if (status < 0) { dev_dbg(dev, "setup of GPIO %s failed\n", con_id); gpiod_put(desc); return ERR_PTR(status); } return desc; } EXPORT_SYMBOL_GPL(gpiod_get_index); /** * gpiod_get_from_of_node() - obtain a GPIO from an OF node * @node: handle of the OF node * @propname: name of the DT property representing the GPIO * @index: index of the GPIO to obtain for the consumer * @dflags: GPIO initialization flags * @label: label to attach to the requested GPIO * * Returns: * On successful request the GPIO pin is configured in accordance with * provided @dflags. If the node does not have the requested GPIO * property, NULL is returned. * * In case of error an ERR_PTR() is returned. */ struct gpio_desc *gpiod_get_from_of_node(struct device_node *node, const char *propname, int index, enum gpiod_flags dflags, const char *label) { struct gpio_desc *desc; unsigned long lflags = 0; enum of_gpio_flags flags; bool active_low = false; bool single_ended = false; bool open_drain = false; bool transitory = false; int ret; desc = of_get_named_gpiod_flags(node, propname, index, &flags); if (!desc || IS_ERR(desc)) { /* If it is not there, just return NULL */ if (PTR_ERR(desc) == -ENOENT) return NULL; return desc; } active_low = flags & OF_GPIO_ACTIVE_LOW; single_ended = flags & OF_GPIO_SINGLE_ENDED; open_drain = flags & OF_GPIO_OPEN_DRAIN; transitory = flags & OF_GPIO_TRANSITORY; ret = gpiod_request(desc, label); if (ret) return ERR_PTR(ret); if (active_low) lflags |= GPIO_ACTIVE_LOW; if (single_ended) { if (open_drain) lflags |= GPIO_OPEN_DRAIN; else lflags |= GPIO_OPEN_SOURCE; } if (transitory) lflags |= GPIO_TRANSITORY; ret = gpiod_configure_flags(desc, propname, lflags, dflags); if (ret < 0) { gpiod_put(desc); return ERR_PTR(ret); } return desc; } EXPORT_SYMBOL(gpiod_get_from_of_node); /** * fwnode_get_named_gpiod - obtain a GPIO from firmware node * @fwnode: handle of the firmware node * @propname: name of the firmware property representing the GPIO * @index: index of the GPIO to obtain for the consumer * @dflags: GPIO initialization flags * @label: label to attach to the requested GPIO * * This function can be used for drivers that get their configuration * from opaque firmware. * * The function properly finds the corresponding GPIO using whatever is the * underlying firmware interface and then makes sure that the GPIO * descriptor is requested before it is returned to the caller. * * Returns: * On successful request the GPIO pin is configured in accordance with * provided @dflags. * * In case of error an ERR_PTR() is returned. */ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, const char *propname, int index, enum gpiod_flags dflags, const char *label) { struct gpio_desc *desc = ERR_PTR(-ENODEV); unsigned long lflags = 0; int ret; if (!fwnode) return ERR_PTR(-EINVAL); if (is_of_node(fwnode)) { desc = gpiod_get_from_of_node(to_of_node(fwnode), propname, index, dflags, label); return desc; } else if (is_acpi_node(fwnode)) { struct acpi_gpio_info info; desc = acpi_node_get_gpiod(fwnode, propname, index, &info); if (IS_ERR(desc)) return desc; acpi_gpio_update_gpiod_flags(&dflags, &info); if (info.polarity == GPIO_ACTIVE_LOW) lflags |= GPIO_ACTIVE_LOW; } /* Currently only ACPI takes this path */ ret = gpiod_request(desc, label); if (ret) return ERR_PTR(ret); ret = gpiod_configure_flags(desc, propname, lflags, dflags); if (ret < 0) { gpiod_put(desc); return ERR_PTR(ret); } return desc; } EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod); /** * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO * function * @dev: GPIO consumer, can be NULL for system-global GPIOs * @con_id: function within the GPIO consumer * @index: index of the GPIO to obtain in the consumer * @flags: optional GPIO initialization flags * * This is equivalent to gpiod_get_index(), except that when no GPIO with the * specified index was assigned to the requested function it will return NULL. * This is convenient for drivers that need to handle optional GPIOs. */ struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev, const char *con_id, unsigned int index, enum gpiod_flags flags) { struct gpio_desc *desc; desc = gpiod_get_index(dev, con_id, index, flags); if (IS_ERR(desc)) { if (PTR_ERR(desc) == -ENOENT) return NULL; } return desc; } EXPORT_SYMBOL_GPL(gpiod_get_index_optional); /** * gpiod_hog - Hog the specified GPIO desc given the provided flags * @desc: gpio whose value will be assigned * @name: gpio line name * @lflags: gpio_lookup_flags - returned from of_find_gpio() or * of_get_gpio_hog() * @dflags: gpiod_flags - optional GPIO initialization flags */ int gpiod_hog(struct gpio_desc *desc, const char *name, unsigned long lflags, enum gpiod_flags dflags) { struct gpio_chip *chip; struct gpio_desc *local_desc; int hwnum; int status; chip = gpiod_to_chip(desc); hwnum = gpio_chip_hwgpio(desc); local_desc = gpiochip_request_own_desc(chip, hwnum, name); if (IS_ERR(local_desc)) { status = PTR_ERR(local_desc); pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n", name, chip->label, hwnum, status); return status; } status = gpiod_configure_flags(desc, name, lflags, dflags); if (status < 0) { pr_err("setup of hog GPIO %s (chip %s, offset %d) failed, %d\n", name, chip->label, hwnum, status); gpiochip_free_own_desc(desc); return status; } /* Mark GPIO as hogged so it can be identified and removed later */ set_bit(FLAG_IS_HOGGED, &desc->flags); pr_info("GPIO line %d (%s) hogged as %s%s\n", desc_to_gpio(desc), name, (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input", (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":""); return 0; } /** * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog * @chip: gpio chip to act on * * This is only used by of_gpiochip_remove to free hogged gpios */ static void gpiochip_free_hogs(struct gpio_chip *chip) { int id; for (id = 0; id < chip->ngpio; id++) { if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags)) gpiochip_free_own_desc(&chip->gpiodev->descs[id]); } } /** * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function * @dev: GPIO consumer, can be NULL for system-global GPIOs * @con_id: function within the GPIO consumer * @flags: optional GPIO initialization flags * * This function acquires all the GPIOs defined under a given function. * * Return a struct gpio_descs containing an array of descriptors, -ENOENT if * no GPIO has been assigned to the requested function, or another IS_ERR() * code if an error occurred while trying to acquire the GPIOs. */ struct gpio_descs *__must_check gpiod_get_array(struct device *dev, const char *con_id, enum gpiod_flags flags) { struct gpio_desc *desc; struct gpio_descs *descs; struct gpio_array *array_info = NULL; struct gpio_chip *chip; int count, bitmap_size; count = gpiod_count(dev, con_id); if (count < 0) return ERR_PTR(count); descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL); if (!descs) return ERR_PTR(-ENOMEM); for (descs->ndescs = 0; descs->ndescs < count; ) { desc = gpiod_get_index(dev, con_id, descs->ndescs, flags); if (IS_ERR(desc)) { gpiod_put_array(descs); return ERR_CAST(desc); } descs->desc[descs->ndescs] = desc; chip = gpiod_to_chip(desc); /* * If pin hardware number of array member 0 is also 0, select * its chip as a candidate for fast bitmap processing path. */ if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) { struct gpio_descs *array; bitmap_size = BITS_TO_LONGS(chip->ngpio > count ? chip->ngpio : count); array = kzalloc(struct_size(descs, desc, count) + struct_size(array_info, invert_mask, 3 * bitmap_size), GFP_KERNEL); if (!array) { gpiod_put_array(descs); return ERR_PTR(-ENOMEM); } memcpy(array, descs, struct_size(descs, desc, descs->ndescs + 1)); kfree(descs); descs = array; array_info = (void *)(descs->desc + count); array_info->get_mask = array_info->invert_mask + bitmap_size; array_info->set_mask = array_info->get_mask + bitmap_size; array_info->desc = descs->desc; array_info->size = count; array_info->chip = chip; bitmap_set(array_info->get_mask, descs->ndescs, count - descs->ndescs); bitmap_set(array_info->set_mask, descs->ndescs, count - descs->ndescs); descs->info = array_info; } /* Unmark array members which don't belong to the 'fast' chip */ if (array_info && array_info->chip != chip) { __clear_bit(descs->ndescs, array_info->get_mask); __clear_bit(descs->ndescs, array_info->set_mask); } /* * Detect array members which belong to the 'fast' chip * but their pins are not in hardware order. */ else if (array_info && gpio_chip_hwgpio(desc) != descs->ndescs) { /* * Don't use fast path if all array members processed so * far belong to the same chip as this one but its pin * hardware number is different from its array index. */ if (bitmap_full(array_info->get_mask, descs->ndescs)) { array_info = NULL; } else { __clear_bit(descs->ndescs, array_info->get_mask); __clear_bit(descs->ndescs, array_info->set_mask); } } else if (array_info) { /* Exclude open drain or open source from fast output */ if (gpiochip_line_is_open_drain(chip, descs->ndescs) || gpiochip_line_is_open_source(chip, descs->ndescs)) __clear_bit(descs->ndescs, array_info->set_mask); /* Identify 'fast' pins which require invertion */ if (gpiod_is_active_low(desc)) __set_bit(descs->ndescs, array_info->invert_mask); } descs->ndescs++; } if (array_info) dev_dbg(dev, "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n", array_info->chip->label, array_info->size, *array_info->get_mask, *array_info->set_mask, *array_info->invert_mask); return descs; } EXPORT_SYMBOL_GPL(gpiod_get_array); /** * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO * function * @dev: GPIO consumer, can be NULL for system-global GPIOs * @con_id: function within the GPIO consumer * @flags: optional GPIO initialization flags * * This is equivalent to gpiod_get_array(), except that when no GPIO was * assigned to the requested function it will return NULL. */ struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev, const char *con_id, enum gpiod_flags flags) { struct gpio_descs *descs; descs = gpiod_get_array(dev, con_id, flags); if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT)) return NULL; return descs; } EXPORT_SYMBOL_GPL(gpiod_get_array_optional); /** * gpiod_put - dispose of a GPIO descriptor * @desc: GPIO descriptor to dispose of * * No descriptor can be used after gpiod_put() has been called on it. */ void gpiod_put(struct gpio_desc *desc) { gpiod_free(desc); } EXPORT_SYMBOL_GPL(gpiod_put); /** * gpiod_put_array - dispose of multiple GPIO descriptors * @descs: struct gpio_descs containing an array of descriptors */ void gpiod_put_array(struct gpio_descs *descs) { unsigned int i; for (i = 0; i < descs->ndescs; i++) gpiod_put(descs->desc[i]); kfree(descs); } EXPORT_SYMBOL_GPL(gpiod_put_array); static int __init gpiolib_dev_init(void) { int ret; /* Register GPIO sysfs bus */ ret = bus_register(&gpio_bus_type); if (ret < 0) { pr_err("gpiolib: could not register GPIO bus type\n"); return ret; } ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip"); if (ret < 0) { pr_err("gpiolib: failed to allocate char dev region\n"); bus_unregister(&gpio_bus_type); } else { gpiolib_initialized = true; gpiochip_setup_devs(); } return ret; } core_initcall(gpiolib_dev_init); #ifdef CONFIG_DEBUG_FS static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev) { unsigned i; struct gpio_chip *chip = gdev->chip; unsigned gpio = gdev->base; struct gpio_desc *gdesc = &gdev->descs[0]; bool is_out; bool is_irq; bool active_low; for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) { if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) { if (gdesc->name) { seq_printf(s, " gpio-%-3d (%-20.20s)\n", gpio, gdesc->name); } continue; } gpiod_get_direction(gdesc); is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags); seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s", gpio, gdesc->name ? gdesc->name : "", gdesc->label, is_out ? "out" : "in ", chip->get ? (chip->get(chip, i) ? "hi" : "lo") : "? ", is_irq ? "IRQ " : "", active_low ? "ACTIVE LOW" : ""); seq_printf(s, "\n"); } } static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) { unsigned long flags; struct gpio_device *gdev = NULL; loff_t index = *pos; s->private = ""; spin_lock_irqsave(&gpio_lock, flags); list_for_each_entry(gdev, &gpio_devices, list) if (index-- == 0) { spin_unlock_irqrestore(&gpio_lock, flags); return gdev; } spin_unlock_irqrestore(&gpio_lock, flags); return NULL; } static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) { unsigned long flags; struct gpio_device *gdev = v; void *ret = NULL; spin_lock_irqsave(&gpio_lock, flags); if (list_is_last(&gdev->list, &gpio_devices)) ret = NULL; else ret = list_entry(gdev->list.next, struct gpio_device, list); spin_unlock_irqrestore(&gpio_lock, flags); s->private = "\n"; ++*pos; return ret; } static void gpiolib_seq_stop(struct seq_file *s, void *v) { } static int gpiolib_seq_show(struct seq_file *s, void *v) { struct gpio_device *gdev = v; struct gpio_chip *chip = gdev->chip; struct device *parent; if (!chip) { seq_printf(s, "%s%s: (dangling chip)", (char *)s->private, dev_name(&gdev->dev)); return 0; } seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private, dev_name(&gdev->dev), gdev->base, gdev->base + gdev->ngpio - 1); parent = chip->parent; if (parent) seq_printf(s, ", parent: %s/%s", parent->bus ? parent->bus->name : "no-bus", dev_name(parent)); if (chip->label) seq_printf(s, ", %s", chip->label); if (chip->can_sleep) seq_printf(s, ", can sleep"); seq_printf(s, ":\n"); if (chip->dbg_show) chip->dbg_show(s, chip); else gpiolib_dbg_show(s, gdev); return 0; } static const struct seq_operations gpiolib_seq_ops = { .start = gpiolib_seq_start, .next = gpiolib_seq_next, .stop = gpiolib_seq_stop, .show = gpiolib_seq_show, }; static int gpiolib_open(struct inode *inode, struct file *file) { return seq_open(file, &gpiolib_seq_ops); } static const struct file_operations gpiolib_operations = { .owner = THIS_MODULE, .open = gpiolib_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release, }; static int __init gpiolib_debugfs_init(void) { /* /sys/kernel/debug/gpio */ (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL, &gpiolib_operations); return 0; } subsys_initcall(gpiolib_debugfs_init); #endif /* DEBUG_FS */
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