Release 4.12 drivers/gpio/gpiolib-sysfs.c

#include <linux/idr.h>
#include <linux/mutex.h>
#include <linux/device.h>
#include <linux/sysfs.h>
#include <linux/gpio/consumer.h>
#include <linux/gpio/driver.h>
#include <linux/interrupt.h>
#include <linux/kdev_t.h>
#include <linux/slab.h>

#include "gpiolib.h"


#define GPIO_IRQF_TRIGGER_FALLING	BIT(0)

#define GPIO_IRQF_TRIGGER_RISING	BIT(1)

#define GPIO_IRQF_TRIGGER_BOTH		(GPIO_IRQF_TRIGGER_FALLING | \
                                         GPIO_IRQF_TRIGGER_RISING)


struct gpiod_data {
	
struct gpio_desc *desc;

	
struct mutex mutex;
	
struct kernfs_node *value_kn;
	
int irq;
	
unsigned char irq_flags;

	
bool direction_can_change;
};

/*
 * Lock to serialise gpiod export and unexport, and prevent re-export of
 * gpiod whose chip is being unregistered.
 */
static DEFINE_MUTEX(sysfs_lock);

/*
 * /sys/class/gpio/gpioN... only for GPIOs that are exported
 *   /direction
 *      * MAY BE OMITTED if kernel won't allow direction changes
 *      * is read/write as "in" or "out"
 *      * may also be written as "high" or "low", initializing
 *        output value as specified ("out" implies "low")
 *   /value
 *      * always readable, subject to hardware behavior
 *      * may be writable, as zero/nonzero
 *   /edge
 *      * configures behavior of poll(2) on /value
 *      * available only if pin can generate IRQs on input
 *      * is read/write as "none", "falling", "rising", or "both"
 *   /active_low
 *      * configures polarity of /value
 *      * is read/write as zero/nonzero
 *      * also affects existing and subsequent "falling" and "rising"
 *        /edge configuration
 */



static ssize_t direction_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct gpiod_data *data = dev_get_drvdata(dev);
	struct gpio_desc *desc = data->desc;
	ssize_t			status;

	mutex_lock(&data->mutex);

	gpiod_get_direction(desc);
	status = sprintf(buf, "%s\n",
			test_bit(FLAG_IS_OUT, &desc->flags)
				? "out" : "in");

	mutex_unlock(&data->mutex);

	return status;
}

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static ssize_t direction_store(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t size)
{
	struct gpiod_data *data = dev_get_drvdata(dev);
	struct gpio_desc *desc = data->desc;
	ssize_t			status;

	mutex_lock(&data->mutex);

	if (sysfs_streq(buf, "high"))
		status = gpiod_direction_output_raw(desc, 1);
	else if (sysfs_streq(buf, "out") || sysfs_streq(buf, "low"))
		status = gpiod_direction_output_raw(desc, 0);
	else if (sysfs_streq(buf, "in"))
		status = gpiod_direction_input(desc);
	else
		status = -EINVAL;

	mutex_unlock(&data->mutex);

	return status ? : size;
}
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static DEVICE_ATTR_RW(direction);



static ssize_t value_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct gpiod_data *data = dev_get_drvdata(dev);
	struct gpio_desc *desc = data->desc;
	ssize_t			status;

	mutex_lock(&data->mutex);

	status = sprintf(buf, "%d\n", gpiod_get_value_cansleep(desc));

	mutex_unlock(&data->mutex);

	return status;
}

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static ssize_t value_store(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t size)
{
	struct gpiod_data *data = dev_get_drvdata(dev);
	struct gpio_desc *desc = data->desc;
	ssize_t			status;

	mutex_lock(&data->mutex);

	if (!test_bit(FLAG_IS_OUT, &desc->flags)) {
		status = -EPERM;
	} else {
		long		value;

		status = kstrtol(buf, 0, &value);
		if (status == 0) {
			gpiod_set_value_cansleep(desc, value);
			status = size;
		}
	}

	mutex_unlock(&data->mutex);

	return status;
}
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static DEVICE_ATTR_RW(value);



static irqreturn_t gpio_sysfs_irq(int irq, void *priv)
{
	struct gpiod_data *data = priv;

	sysfs_notify_dirent(data->value_kn);

	return IRQ_HANDLED;
}

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/* Caller holds gpiod-data mutex. */


static int gpio_sysfs_request_irq(struct device *dev, unsigned char flags)
{
	struct gpiod_data	*data = dev_get_drvdata(dev);
	struct gpio_desc	*desc = data->desc;
	unsigned long		irq_flags;
	int			ret;

	data->irq = gpiod_to_irq(desc);
	if (data->irq < 0)
		return -EIO;

	data->value_kn = sysfs_get_dirent(dev->kobj.sd, "value");
	if (!data->value_kn)
		return -ENODEV;

	irq_flags = IRQF_SHARED;
	if (flags & GPIO_IRQF_TRIGGER_FALLING)
		irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
			IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
	if (flags & GPIO_IRQF_TRIGGER_RISING)
		irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
			IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;

	/*
         * FIXME: This should be done in the irq_request_resources callback
         *        when the irq is requested, but a few drivers currently fail
         *        to do so.
         *
         *        Remove this redundant call (along with the corresponding
         *        unlock) when those drivers have been fixed.
         */
	ret = gpiochip_lock_as_irq(desc->gdev->chip, gpio_chip_hwgpio(desc));
	if (ret < 0)
		goto err_put_kn;

	ret = request_any_context_irq(data->irq, gpio_sysfs_irq, irq_flags,
				"gpiolib", data);
	if (ret < 0)
		goto err_unlock;

	data->irq_flags = flags;

	return 0;

err_unlock:
	gpiochip_unlock_as_irq(desc->gdev->chip, gpio_chip_hwgpio(desc));
err_put_kn:
	sysfs_put(data->value_kn);

	return ret;
}

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/*
 * Caller holds gpiod-data mutex (unless called after class-device
 * deregistration).
 */


static void gpio_sysfs_free_irq(struct device *dev)
{
	struct gpiod_data *data = dev_get_drvdata(dev);
	struct gpio_desc *desc = data->desc;

	data->irq_flags = 0;
	free_irq(data->irq, data);
	gpiochip_unlock_as_irq(desc->gdev->chip, gpio_chip_hwgpio(desc));
	sysfs_put(data->value_kn);
}

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static const struct {
	
const char *name;
	
unsigned char flags;

} trigger_types[] = {
	{ "none",    0 },
	{ "falling", GPIO_IRQF_TRIGGER_FALLING },
	{ "rising",  GPIO_IRQF_TRIGGER_RISING },
	{ "both",    GPIO_IRQF_TRIGGER_BOTH },
};



static ssize_t edge_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct gpiod_data *data = dev_get_drvdata(dev);
	ssize_t	status = 0;
	int i;

	mutex_lock(&data->mutex);

	for (i = 0; i < ARRAY_SIZE(trigger_types); i++) {
		if (data->irq_flags == trigger_types[i].flags) {
			status = sprintf(buf, "%s\n", trigger_types[i].name);
			break;
		}
	}

	mutex_unlock(&data->mutex);

	return status;
}

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static ssize_t edge_store(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t size)
{
	struct gpiod_data *data = dev_get_drvdata(dev);
	unsigned char flags;
	ssize_t	status = size;
	int i;

	for (i = 0; i < ARRAY_SIZE(trigger_types); i++) {
		if (sysfs_streq(trigger_types[i].name, buf))
			break;
	}

	if (i == ARRAY_SIZE(trigger_types))
		return -EINVAL;

	flags = trigger_types[i].flags;

	mutex_lock(&data->mutex);

	if (flags == data->irq_flags) {
		status = size;
		goto out_unlock;
	}

	if (data->irq_flags)
		gpio_sysfs_free_irq(dev);

	if (flags) {
		status = gpio_sysfs_request_irq(dev, flags);
		if (!status)
			status = size;
	}

out_unlock:
	mutex_unlock(&data->mutex);

	return status;
}
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static DEVICE_ATTR_RW(edge);

/* Caller holds gpiod-data mutex. */


static int gpio_sysfs_set_active_low(struct device *dev, int value)
{
	struct gpiod_data	*data = dev_get_drvdata(dev);
	struct gpio_desc	*desc = data->desc;
	int			status = 0;
	unsigned int		flags = data->irq_flags;

	if (!!test_bit(FLAG_ACTIVE_LOW, &desc->flags) == !!value)
		return 0;

	if (value)
		set_bit(FLAG_ACTIVE_LOW, &desc->flags);
	else
		clear_bit(FLAG_ACTIVE_LOW, &desc->flags);

	/* reconfigure poll(2) support if enabled on one edge only */
	if (flags == GPIO_IRQF_TRIGGER_FALLING ||
					flags == GPIO_IRQF_TRIGGER_RISING) {
		gpio_sysfs_free_irq(dev);
		status = gpio_sysfs_request_irq(dev, flags);
	}

	return status;
}

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static ssize_t active_low_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct gpiod_data *data = dev_get_drvdata(dev);
	struct gpio_desc *desc = data->desc;
	ssize_t			status;

	mutex_lock(&data->mutex);

	status = sprintf(buf, "%d\n",
				!!test_bit(FLAG_ACTIVE_LOW, &desc->flags));

	mutex_unlock(&data->mutex);

	return status;
}

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static ssize_t active_low_store(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t size)
{
	struct gpiod_data	*data = dev_get_drvdata(dev);
	ssize_t			status;
	long			value;

	mutex_lock(&data->mutex);

	status = kstrtol(buf, 0, &value);
	if (status == 0)
		status = gpio_sysfs_set_active_low(dev, value);

	mutex_unlock(&data->mutex);

	return status ? : size;
}
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static DEVICE_ATTR_RW(active_low);



static umode_t gpio_is_visible(struct kobject *kobj, struct attribute *attr,
			       int n)
{
	struct device *dev = container_of(kobj, struct device, kobj);
	struct gpiod_data *data = dev_get_drvdata(dev);
	struct gpio_desc *desc = data->desc;
	umode_t mode = attr->mode;
	bool show_direction = data->direction_can_change;

	if (attr == &dev_attr_direction.attr) {
		if (!show_direction)
			mode = 0;
	} else if (attr == &dev_attr_edge.attr) {
		if (gpiod_to_irq(desc) < 0)
			mode = 0;
		if (!show_direction && test_bit(FLAG_IS_OUT, &desc->flags))
			mode = 0;
	}

	return mode;
}

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static struct attribute *gpio_attrs[] = {
	&dev_attr_direction.attr,
	&dev_attr_edge.attr,
	&dev_attr_value.attr,
	&dev_attr_active_low.attr,
	NULL,
};


static const struct attribute_group gpio_group = {
	.attrs = gpio_attrs,
	.is_visible = gpio_is_visible,
};


static const struct attribute_group *gpio_groups[] = {
	&gpio_group,
	NULL
};

/*
 * /sys/class/gpio/gpiochipN/
 *   /base ... matching gpio_chip.base (N)
 *   /label ... matching gpio_chip.label
 *   /ngpio ... matching gpio_chip.ngpio
 */



static ssize_t base_show(struct device *dev,
			       struct device_attribute *attr, char *buf)
{
	const struct gpio_chip	*chip = dev_get_drvdata(dev);

	return sprintf(buf, "%d\n", chip->base);
}
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static DEVICE_ATTR_RO(base);



static ssize_t label_show(struct device *dev,
			       struct device_attribute *attr, char *buf)
{
	const struct gpio_chip	*chip = dev_get_drvdata(dev);

	return sprintf(buf, "%s\n", chip->label ? : "");
}
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static DEVICE_ATTR_RO(label);



static ssize_t ngpio_show(struct device *dev,
			       struct device_attribute *attr, char *buf)
{
	const struct gpio_chip	*chip = dev_get_drvdata(dev);

	return sprintf(buf, "%u\n", chip->ngpio);
}
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static DEVICE_ATTR_RO(ngpio);


static struct attribute *gpiochip_attrs[] = {
	&dev_attr_base.attr,
	&dev_attr_label.attr,
	&dev_attr_ngpio.attr,
	NULL,
};

ATTRIBUTE_GROUPS(gpiochip);

/*
 * /sys/class/gpio/export ... write-only
 *      integer N ... number of GPIO to export (full access)
 * /sys/class/gpio/unexport ... write-only
 *      integer N ... number of GPIO to unexport
 */


static ssize_t export_store(struct class *class,
				struct class_attribute *attr,
				const char *buf, size_t len)
{
	long			gpio;
	struct gpio_desc	*desc;
	int			status;

	status = kstrtol(buf, 0, &gpio);
	if (status < 0)
		goto done;

	desc = gpio_to_desc(gpio);
	/* reject invalid GPIOs */
	if (!desc) {
		pr_warn("%s: invalid GPIO %ld\n", __func__, gpio);
		return -EINVAL;
	}

	/* No extra locking here; FLAG_SYSFS just signifies that the
         * request and export were done by on behalf of userspace, so
         * they may be undone on its behalf too.
         */

	status = gpiod_request(desc, "sysfs");
	if (status < 0) {
		if (status == -EPROBE_DEFER)
			status = -ENODEV;
		goto done;
	}
	status = gpiod_export(desc, true);
	if (status < 0)
		gpiod_free(desc);
	else
		set_bit(FLAG_SYSFS, &desc->flags);

done:
	if (status)
		pr_debug("%s: status %d\n", __func__, status);
	return status ? : len;
}

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static ssize_t unexport_store(struct class *class,
				struct class_attribute *attr,
				const char *buf, size_t len)
{
	long			gpio;
	struct gpio_desc	*desc;
	int			status;

	status = kstrtol(buf, 0, &gpio);
	if (status < 0)
		goto done;

	desc = gpio_to_desc(gpio);
	/* reject bogus commands (gpio_unexport ignores them) */
	if (!desc) {
		pr_warn("%s: invalid GPIO %ld\n", __func__, gpio);
		return -EINVAL;
	}

	status = -EINVAL;

	/* No extra locking here; FLAG_SYSFS just signifies that the
         * request and export were done by on behalf of userspace, so
         * they may be undone on its behalf too.
         */
	if (test_and_clear_bit(FLAG_SYSFS, &desc->flags)) {
		status = 0;
		gpiod_free(desc);
	}
done:
	if (status)
		pr_debug("%s: status %d\n", __func__, status);
	return status ? : len;
}

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static struct class_attribute gpio_class_attrs[] = {
	__ATTR(export, 0200, NULL, export_store),
	__ATTR(unexport, 0200, NULL, unexport_store),
	__ATTR_NULL,
};


static struct class gpio_class = {
	.name =		"gpio",
	.owner =	THIS_MODULE,

	.class_attrs =	gpio_class_attrs,
};


/**
 * gpiod_export - export a GPIO through sysfs
 * @gpio: gpio to make available, already requested
 * @direction_may_change: true if userspace may change gpio direction
 * Context: arch_initcall or later
 *
 * When drivers want to make a GPIO accessible to userspace after they
 * have requested it -- perhaps while debugging, or as part of their
 * public interface -- they may use this routine.  If the GPIO can
 * change direction (some can't) and the caller allows it, userspace
 * will see "direction" sysfs attribute which may be used to change
 * the gpio's direction.  A "value" attribute will always be provided.
 *
 * Returns zero on success, else an error.
 */


int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
{
	struct gpio_chip	*chip;
	struct gpio_device	*gdev;
	struct gpiod_data	*data;
	unsigned long		flags;
	int			status;
	const char		*ioname = NULL;
	struct device		*dev;
	int			offset;

	/* can't export until sysfs is available ... */
	if (!gpio_class.p) {
		pr_debug("%s: called too early!\n", __func__);
		return -ENOENT;
	}

	if (!desc) {
		pr_debug("%s: invalid gpio descriptor\n", __func__);
		return -EINVAL;
	}

	gdev = desc->gdev;
	chip = gdev->chip;

	mutex_lock(&sysfs_lock);

	/* check if chip is being removed */
	if (!chip || !gdev->mockdev) {
		status = -ENODEV;
		goto err_unlock;
	}

	spin_lock_irqsave(&gpio_lock, flags);
	if (!test_bit(FLAG_REQUESTED, &desc->flags) ||
	     test_bit(FLAG_EXPORT, &desc->flags)) {
		spin_unlock_irqrestore(&gpio_lock, flags);
		gpiod_dbg(desc, "%s: unavailable (requested=%d, exported=%d)\n",
				__func__,
				test_bit(FLAG_REQUESTED, &desc->flags),
				test_bit(FLAG_EXPORT, &desc->flags));
		status = -EPERM;
		goto err_unlock;
	}
	spin_unlock_irqrestore(&gpio_lock, flags);

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	if (!data) {
		status = -ENOMEM;
		goto err_unlock;
	}

	data->desc = desc;
	mutex_init(&data->mutex);
	if (chip->direction_input && chip->direction_output)
		data->direction_can_change = direction_may_change;
	else
		data->direction_can_change = false;

	offset = gpio_chip_hwgpio(desc);
	if (chip->names && chip->names[offset])
		ioname = chip->names[offset];

	dev = device_create_with_groups(&gpio_class, &gdev->dev,
					MKDEV(0, 0), data, gpio_groups,
					ioname ? ioname : "gpio%u",
					desc_to_gpio(desc));
	if (IS_ERR(dev)) {
		status = PTR_ERR(dev);
		goto err_free_data;
	}

	set_bit(FLAG_EXPORT, &desc->flags);
	mutex_unlock(&sysfs_lock);
	return 0;

err_free_data:
	kfree(data);
err_unlock:
	mutex_unlock(&sysfs_lock);
	gpiod_dbg(desc, "%s: status %d\n", __func__, status);
	return status;
}
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EXPORT_SYMBOL_GPL(gpiod_export);



static int match_export(struct device *dev, const void *desc)
{
	struct gpiod_data *data = dev_get_drvdata(dev);

	return data->desc == desc;
}

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/**
 * gpiod_export_link - create a sysfs link to an exported GPIO node
 * @dev: device under which to create symlink
 * @name: name of the symlink
 * @gpio: gpio to create symlink to, already exported
 *
 * Set up a symlink from /sys/.../dev/name to /sys/class/gpio/gpioN
 * node. Caller is responsible for unlinking.
 *
 * Returns zero on success, else an error.
 */


int gpiod_export_link(struct device *dev, const char *name,
		      struct gpio_desc *desc)
{
	struct device *cdev;
	int ret;

	if (!desc) {
		pr_warn("%s: invalid GPIO\n", __func__);
		return -EINVAL;
	}

	cdev = class_find_device(&gpio_class, NULL, desc, match_export);
	if (!cdev)
		return -ENODEV;

	ret = sysfs_create_link(&dev->kobj, &cdev->kobj, name);
	put_device(cdev);

	return ret;
}
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Alexandre Courbot
75
79.79%
1
33.33%
Johan Hovold
19
20.21%
2
66.67%
Total
94
100.00%
3
100.00%


EXPORT_SYMBOL_GPL(gpiod_export_link);

/**
 * gpiod_unexport - reverse effect of gpiod_export()
 * @gpio: gpio to make unavailable
 *
 * This is implicit on gpiod_free().
 */


void gpiod_unexport(struct gpio_desc *desc)
{
	struct gpiod_data *data;
	struct device *dev;

	if (!desc) {
		pr_warn("%s: invalid GPIO\n", __func__);
		return;
	}

	mutex_lock(&sysfs_lock);

	if (!test_bit(FLAG_EXPORT, &desc->flags))
		goto err_unlock;

	dev = class_find_device(&gpio_class, NULL, desc, match_export);
	if (!dev)
		goto err_unlock;

	data = dev_get_drvdata(dev);

	clear_bit(FLAG_EXPORT, &desc->flags);

	device_unregister(dev);

	/*
         * Release irq after deregistration to prevent race with edge_store.
         */
	if (data->irq_flags)
		gpio_sysfs_free_irq(dev);

	mutex_unlock(&sysfs_lock);

	put_device(dev);
	kfree(data);

	return;

err_unlock:
	mutex_unlock(&sysfs_lock);
}
Contributors
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CommitProp
Alexandre Courbot
89
64.49%
1
14.29%
Johan Hovold
49
35.51%
6
85.71%
Total
138
100.00%
7
100.00%


EXPORT_SYMBOL_GPL(gpiod_unexport);



int gpiochip_sysfs_register(struct gpio_device *gdev)
{
	struct device	*dev;
	struct device	*parent;
	struct gpio_chip *chip = gdev->chip;

	/*
         * Many systems add gpio chips for SOC support very early,
         * before driver model support is available.  In those cases we
         * register later, in gpiolib_sysfs_init() ... here we just
         * verify that _some_ field of gpio_class got initialized.
         */
	if (!gpio_class.p)
		return 0;

	/*
         * For sysfs backward compatibility we need to preserve this
         * preferred parenting to the gpio_chip parent field, if set.
         */
	if (chip->parent)
		parent = chip->parent;
	else
		parent = &gdev->dev;

	/* use chip->base for the ID; it's already known to be unique */
	dev = device_create_with_groups(&gpio_class, parent,
					MKDEV(0, 0),
					chip, gpiochip_groups,
					"gpiochip%d", chip->base);
	if (IS_ERR(dev))
		return PTR_ERR(dev);

	mutex_lock(&sysfs_lock);
	gdev->mockdev = dev;
	mutex_unlock(&sysfs_lock);

	return 0;
}

Contributors
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CommitProp
Alexandre Courbot
67
54.47%
1
14.29%
Bamvor Jian Zhang
27
21.95%
1
14.29%
Johan Hovold
16
13.01%
4
57.14%
Linus Walleij
13
10.57%
1
14.29%
Total
123
100.00%
7
100.00%



void gpiochip_sysfs_unregister(struct gpio_device *gdev)
{
	struct gpio_desc *desc;
	struct gpio_chip *chip = gdev->chip;
	unsigned int i;

	if (!gdev->mockdev)
		return;

	device_unregister(gdev->mockdev);

	/* prevent further gpiod exports */
	mutex_lock(&sysfs_lock);
	gdev->mockdev = NULL;
	mutex_unlock(&sysfs_lock);

	/* unregister gpiod class devices owned by sysfs */
	for (i = 0; i < chip->ngpio; i++) {
		desc = &gdev->descs[i];
		if (test_and_clear_bit(FLAG_SYSFS, &desc->flags))
			gpiod_free(desc);
	}
}

Contributors
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CommitProp
Johan Hovold
70
65.42%
4
50.00%
Linus Walleij
20
18.69%
3
37.50%
Alexandre Courbot
17
15.89%
1
12.50%
Total
107
100.00%
8
100.00%



static int __init gpiolib_sysfs_init(void)
{
	int		status;
	unsigned long	flags;
	struct gpio_device *gdev;

	status = class_register(&gpio_class);
	if (status < 0)
		return status;

	/* Scan and register the gpio_chips which registered very
         * early (e.g. before the class_register above was called).
         *
         * We run before arch_initcall() so chip->dev nodes can have
         * registered, and so arch_initcall() can always gpio_export().
         */
	spin_lock_irqsave(&gpio_lock, flags);
	list_for_each_entry(gdev, &gpio_devices, list) {
		if (gdev->mockdev)
			continue;

		/*
                 * TODO we yield gpio_lock here because
                 * gpiochip_sysfs_register() acquires a mutex. This is unsafe
                 * and needs to be fixed.
                 *
                 * Also it would be nice to use gpiochip_find() here so we
                 * can keep gpio_chips local to gpiolib.c, but the yield of
                 * gpio_lock prevents us from doing this.
                 */
		spin_unlock_irqrestore(&gpio_lock, flags);
		status = gpiochip_sysfs_register(gdev);
		spin_lock_irqsave(&gpio_lock, flags);
	}
	spin_unlock_irqrestore(&gpio_lock, flags);

	return status;
}
Contributors
Person
Tokens
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CommitProp
Alexandre Courbot
89
89.90%
1
25.00%
Linus Walleij
8
8.08%
2
50.00%
Johan Hovold
2
2.02%
1
25.00%
Total
99
100.00%
4
100.00%


postcore_initcall(gpiolib_sysfs_init);
Overall Contributors
Person
Tokens
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CommitProp
Alexandre Courbot
2199
68.08%
2
6.25%
Johan Hovold
937
29.01%
24
75.00%
Linus Walleij
66
2.04%
4
12.50%
Bamvor Jian Zhang
27
0.84%
1
3.12%
Amitesh Singh
1
0.03%
1
3.12%
Total
3230
100.00%
32
100.00%
Directory: drivers/gpio

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