| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| David Brownell | 7108 | 77.10% | 18 | 16.51% |
| Al Viro | 1024 | 11.11% | 15 | 13.76% |
| Alan Stern | 451 | 4.89% | 12 | 11.01% |
| Milan Svoboda | 142 | 1.54% | 3 | 2.75% |
| Zach Brown | 98 | 1.06% | 1 | 0.92% |
| Bin Liu | 48 | 0.52% | 1 | 0.92% |
| Sebastian Andrzej Siewior | 30 | 0.33% | 3 | 2.75% |
| Marek Szyprowski | 27 | 0.29% | 2 | 1.83% |
| Marcus Nutzinger | 23 | 0.25% | 1 | 0.92% |
| Greg Kroah-Hartman | 22 | 0.24% | 5 | 4.59% |
| Michal Nazarewicz | 19 | 0.21% | 1 | 0.92% |
| Eric W. Biedermann | 17 | 0.18% | 2 | 1.83% |
| Christoph Hellwig | 16 | 0.17% | 3 | 2.75% |
| Thomas Gleixner | 15 | 0.16% | 1 | 0.92% |
| Alan Cox | 13 | 0.14% | 1 | 0.92% |
| Peter Chen | 12 | 0.13% | 2 | 1.83% |
| Elena Reshetova | 11 | 0.12% | 2 | 1.83% |
| Harvey Harrison | 11 | 0.12% | 2 | 1.83% |
| Marc Kleine-Budde | 10 | 0.11% | 1 | 0.92% |
| Matthias Kaehlcke | 9 | 0.10% | 1 | 0.92% |
| Badari Pulavarty | 9 | 0.10% | 1 | 0.92% |
| Tatyana Brokhman | 8 | 0.09% | 1 | 0.92% |
| Eric Sesterhenn / Snakebyte | 8 | 0.09% | 1 | 0.92% |
| David Eccher | 7 | 0.08% | 1 | 0.92% |
| Christophe Jaillet | 7 | 0.08% | 1 | 0.92% |
| Roy Hashimoto | 6 | 0.07% | 1 | 0.92% |
| Andi Kleen | 6 | 0.07% | 1 | 0.92% |
| Julia Lawall | 6 | 0.07% | 1 | 0.92% |
| Phil Endecott | 6 | 0.07% | 1 | 0.92% |
| Thomas Faber | 5 | 0.05% | 1 | 0.92% |
| Alexey Dobriyan | 5 | 0.05% | 3 | 2.75% |
| Binyamin Sharet | 4 | 0.04% | 1 | 0.92% |
| Deepa Dinamani | 4 | 0.04% | 1 | 0.92% |
| Linus Torvalds | 4 | 0.04% | 2 | 1.83% |
| Arjan van de Ven | 3 | 0.03% | 1 | 0.92% |
| Kent Overstreet | 3 | 0.03% | 1 | 0.92% |
| David Howells | 3 | 0.03% | 1 | 0.92% |
| Theodore Y. Ts'o | 3 | 0.03% | 1 | 0.92% |
| Lubomir Rintel | 2 | 0.02% | 1 | 0.92% |
| Luiz Fernando N. Capitulino | 2 | 0.02% | 1 | 0.92% |
| James Morris | 2 | 0.02% | 1 | 0.92% |
| Kirill A. Shutemov | 2 | 0.02% | 1 | 0.92% |
| Mathieu Laurendeau | 2 | 0.02% | 1 | 0.92% |
| Peter Zijlstra | 1 | 0.01% | 1 | 0.92% |
| Steven Cole | 1 | 0.01% | 1 | 0.92% |
| Masahiro Yamada | 1 | 0.01% | 1 | 0.92% |
| Paul Bolle | 1 | 0.01% | 1 | 0.92% |
| Russell King | 1 | 0.01% | 1 | 0.92% |
| Uwe Kleine-König | 1 | 0.01% | 1 | 0.92% |
| Total | 9219 | 109 |
// SPDX-License-Identifier: GPL-2.0+ /* * inode.c -- user mode filesystem api for usb gadget controllers * * Copyright (C) 2003-2004 David Brownell * Copyright (C) 2003 Agilent Technologies */ /* #define VERBOSE_DEBUG */ #include <linux/init.h> #include <linux/module.h> #include <linux/fs.h> #include <linux/pagemap.h> #include <linux/uts.h> #include <linux/wait.h> #include <linux/compiler.h> #include <linux/uaccess.h> #include <linux/sched.h> #include <linux/slab.h> #include <linux/poll.h> #include <linux/mmu_context.h> #include <linux/aio.h> #include <linux/uio.h> #include <linux/refcount.h> #include <linux/delay.h> #include <linux/device.h> #include <linux/moduleparam.h> #include <linux/usb/gadgetfs.h> #include <linux/usb/gadget.h> /* * The gadgetfs API maps each endpoint to a file descriptor so that you * can use standard synchronous read/write calls for I/O. There's some * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode * drivers show how this works in practice. You can also use AIO to * eliminate I/O gaps between requests, to help when streaming data. * * Key parts that must be USB-specific are protocols defining how the * read/write operations relate to the hardware state machines. There * are two types of files. One type is for the device, implementing ep0. * The other type is for each IN or OUT endpoint. In both cases, the * user mode driver must configure the hardware before using it. * * - First, dev_config() is called when /dev/gadget/$CHIP is configured * (by writing configuration and device descriptors). Afterwards it * may serve as a source of device events, used to handle all control * requests other than basic enumeration. * * - Then, after a SET_CONFIGURATION control request, ep_config() is * called when each /dev/gadget/ep* file is configured (by writing * endpoint descriptors). Afterwards these files are used to write() * IN data or to read() OUT data. To halt the endpoint, a "wrong * direction" request is issued (like reading an IN endpoint). * * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe * not possible on all hardware. For example, precise fault handling with * respect to data left in endpoint fifos after aborted operations; or * selective clearing of endpoint halts, to implement SET_INTERFACE. */ #define DRIVER_DESC "USB Gadget filesystem" #define DRIVER_VERSION "24 Aug 2004" static const char driver_desc [] = DRIVER_DESC; static const char shortname [] = "gadgetfs"; MODULE_DESCRIPTION (DRIVER_DESC); MODULE_AUTHOR ("David Brownell"); MODULE_LICENSE ("GPL"); static int ep_open(struct inode *, struct file *); /*----------------------------------------------------------------------*/ #define GADGETFS_MAGIC 0xaee71ee7 /* /dev/gadget/$CHIP represents ep0 and the whole device */ enum ep0_state { /* DISABLED is the initial state. */ STATE_DEV_DISABLED = 0, /* Only one open() of /dev/gadget/$CHIP; only one file tracks * ep0/device i/o modes and binding to the controller. Driver * must always write descriptors to initialize the device, then * the device becomes UNCONNECTED until enumeration. */ STATE_DEV_OPENED, /* From then on, ep0 fd is in either of two basic modes: * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it * - SETUP: read/write will transfer control data and succeed; * or if "wrong direction", performs protocol stall */ STATE_DEV_UNCONNECTED, STATE_DEV_CONNECTED, STATE_DEV_SETUP, /* UNBOUND means the driver closed ep0, so the device won't be * accessible again (DEV_DISABLED) until all fds are closed. */ STATE_DEV_UNBOUND, }; /* enough for the whole queue: most events invalidate others */ #define N_EVENT 5 struct dev_data { spinlock_t lock; refcount_t count; int udc_usage; enum ep0_state state; /* P: lock */ struct usb_gadgetfs_event event [N_EVENT]; unsigned ev_next; struct fasync_struct *fasync; u8 current_config; /* drivers reading ep0 MUST handle control requests (SETUP) * reported that way; else the host will time out. */ unsigned usermode_setup : 1, setup_in : 1, setup_can_stall : 1, setup_out_ready : 1, setup_out_error : 1, setup_abort : 1, gadget_registered : 1; unsigned setup_wLength; /* the rest is basically write-once */ struct usb_config_descriptor *config, *hs_config; struct usb_device_descriptor *dev; struct usb_request *req; struct usb_gadget *gadget; struct list_head epfiles; void *buf; wait_queue_head_t wait; struct super_block *sb; struct dentry *dentry; /* except this scratch i/o buffer for ep0 */ u8 rbuf [256]; }; static inline void get_dev (struct dev_data *data) { refcount_inc (&data->count); } static void put_dev (struct dev_data *data) { if (likely (!refcount_dec_and_test (&data->count))) return; /* needs no more cleanup */ BUG_ON (waitqueue_active (&data->wait)); kfree (data); } static struct dev_data *dev_new (void) { struct dev_data *dev; dev = kzalloc(sizeof(*dev), GFP_KERNEL); if (!dev) return NULL; dev->state = STATE_DEV_DISABLED; refcount_set (&dev->count, 1); spin_lock_init (&dev->lock); INIT_LIST_HEAD (&dev->epfiles); init_waitqueue_head (&dev->wait); return dev; } /*----------------------------------------------------------------------*/ /* other /dev/gadget/$ENDPOINT files represent endpoints */ enum ep_state { STATE_EP_DISABLED = 0, STATE_EP_READY, STATE_EP_ENABLED, STATE_EP_UNBOUND, }; struct ep_data { struct mutex lock; enum ep_state state; refcount_t count; struct dev_data *dev; /* must hold dev->lock before accessing ep or req */ struct usb_ep *ep; struct usb_request *req; ssize_t status; char name [16]; struct usb_endpoint_descriptor desc, hs_desc; struct list_head epfiles; wait_queue_head_t wait; struct dentry *dentry; }; static inline void get_ep (struct ep_data *data) { refcount_inc (&data->count); } static void put_ep (struct ep_data *data) { if (likely (!refcount_dec_and_test (&data->count))) return; put_dev (data->dev); /* needs no more cleanup */ BUG_ON (!list_empty (&data->epfiles)); BUG_ON (waitqueue_active (&data->wait)); kfree (data); } /*----------------------------------------------------------------------*/ /* most "how to use the hardware" policy choices are in userspace: * mapping endpoint roles (which the driver needs) to the capabilities * which the usb controller has. most of those capabilities are exposed * implicitly, starting with the driver name and then endpoint names. */ static const char *CHIP; /*----------------------------------------------------------------------*/ /* NOTE: don't use dev_printk calls before binding to the gadget * at the end of ep0 configuration, or after unbind. */ /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */ #define xprintk(d,level,fmt,args...) \ printk(level "%s: " fmt , shortname , ## args) #ifdef DEBUG #define DBG(dev,fmt,args...) \ xprintk(dev , KERN_DEBUG , fmt , ## args) #else #define DBG(dev,fmt,args...) \ do { } while (0) #endif /* DEBUG */ #ifdef VERBOSE_DEBUG #define VDEBUG DBG #else #define VDEBUG(dev,fmt,args...) \ do { } while (0) #endif /* DEBUG */ #define ERROR(dev,fmt,args...) \ xprintk(dev , KERN_ERR , fmt , ## args) #define INFO(dev,fmt,args...) \ xprintk(dev , KERN_INFO , fmt , ## args) /*----------------------------------------------------------------------*/ /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso) * * After opening, configure non-control endpoints. Then use normal * stream read() and write() requests; and maybe ioctl() to get more * precise FIFO status when recovering from cancellation. */ static void epio_complete (struct usb_ep *ep, struct usb_request *req) { struct ep_data *epdata = ep->driver_data; if (!req->context) return; if (req->status) epdata->status = req->status; else epdata->status = req->actual; complete ((struct completion *)req->context); } /* tasklock endpoint, returning when it's connected. * still need dev->lock to use epdata->ep. */ static int get_ready_ep (unsigned f_flags, struct ep_data *epdata, bool is_write) { int val; if (f_flags & O_NONBLOCK) { if (!mutex_trylock(&epdata->lock)) goto nonblock; if (epdata->state != STATE_EP_ENABLED && (!is_write || epdata->state != STATE_EP_READY)) { mutex_unlock(&epdata->lock); nonblock: val = -EAGAIN; } else val = 0; return val; } val = mutex_lock_interruptible(&epdata->lock); if (val < 0) return val; switch (epdata->state) { case STATE_EP_ENABLED: return 0; case STATE_EP_READY: /* not configured yet */ if (is_write) return 0; // FALLTHRU case STATE_EP_UNBOUND: /* clean disconnect */ break; // case STATE_EP_DISABLED: /* "can't happen" */ default: /* error! */ pr_debug ("%s: ep %p not available, state %d\n", shortname, epdata, epdata->state); } mutex_unlock(&epdata->lock); return -ENODEV; } static ssize_t ep_io (struct ep_data *epdata, void *buf, unsigned len) { DECLARE_COMPLETION_ONSTACK (done); int value; spin_lock_irq (&epdata->dev->lock); if (likely (epdata->ep != NULL)) { struct usb_request *req = epdata->req; req->context = &done; req->complete = epio_complete; req->buf = buf; req->length = len; value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC); } else value = -ENODEV; spin_unlock_irq (&epdata->dev->lock); if (likely (value == 0)) { value = wait_event_interruptible (done.wait, done.done); if (value != 0) { spin_lock_irq (&epdata->dev->lock); if (likely (epdata->ep != NULL)) { DBG (epdata->dev, "%s i/o interrupted\n", epdata->name); usb_ep_dequeue (epdata->ep, epdata->req); spin_unlock_irq (&epdata->dev->lock); wait_event (done.wait, done.done); if (epdata->status == -ECONNRESET) epdata->status = -EINTR; } else { spin_unlock_irq (&epdata->dev->lock); DBG (epdata->dev, "endpoint gone\n"); epdata->status = -ENODEV; } } return epdata->status; } return value; } static int ep_release (struct inode *inode, struct file *fd) { struct ep_data *data = fd->private_data; int value; value = mutex_lock_interruptible(&data->lock); if (value < 0) return value; /* clean up if this can be reopened */ if (data->state != STATE_EP_UNBOUND) { data->state = STATE_EP_DISABLED; data->desc.bDescriptorType = 0; data->hs_desc.bDescriptorType = 0; usb_ep_disable(data->ep); } mutex_unlock(&data->lock); put_ep (data); return 0; } static long ep_ioctl(struct file *fd, unsigned code, unsigned long value) { struct ep_data *data = fd->private_data; int status; if ((status = get_ready_ep (fd->f_flags, data, false)) < 0) return status; spin_lock_irq (&data->dev->lock); if (likely (data->ep != NULL)) { switch (code) { case GADGETFS_FIFO_STATUS: status = usb_ep_fifo_status (data->ep); break; case GADGETFS_FIFO_FLUSH: usb_ep_fifo_flush (data->ep); break; case GADGETFS_CLEAR_HALT: status = usb_ep_clear_halt (data->ep); break; default: status = -ENOTTY; } } else status = -ENODEV; spin_unlock_irq (&data->dev->lock); mutex_unlock(&data->lock); return status; } /*----------------------------------------------------------------------*/ /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */ struct kiocb_priv { struct usb_request *req; struct ep_data *epdata; struct kiocb *iocb; struct mm_struct *mm; struct work_struct work; void *buf; struct iov_iter to; const void *to_free; unsigned actual; }; static int ep_aio_cancel(struct kiocb *iocb) { struct kiocb_priv *priv = iocb->private; struct ep_data *epdata; int value; local_irq_disable(); epdata = priv->epdata; // spin_lock(&epdata->dev->lock); if (likely(epdata && epdata->ep && priv->req)) value = usb_ep_dequeue (epdata->ep, priv->req); else value = -EINVAL; // spin_unlock(&epdata->dev->lock); local_irq_enable(); return value; } static void ep_user_copy_worker(struct work_struct *work) { struct kiocb_priv *priv = container_of(work, struct kiocb_priv, work); struct mm_struct *mm = priv->mm; struct kiocb *iocb = priv->iocb; size_t ret; use_mm(mm); ret = copy_to_iter(priv->buf, priv->actual, &priv->to); unuse_mm(mm); if (!ret) ret = -EFAULT; /* completing the iocb can drop the ctx and mm, don't touch mm after */ iocb->ki_complete(iocb, ret, ret); kfree(priv->buf); kfree(priv->to_free); kfree(priv); } static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req) { struct kiocb *iocb = req->context; struct kiocb_priv *priv = iocb->private; struct ep_data *epdata = priv->epdata; /* lock against disconnect (and ideally, cancel) */ spin_lock(&epdata->dev->lock); priv->req = NULL; priv->epdata = NULL; /* if this was a write or a read returning no data then we * don't need to copy anything to userspace, so we can * complete the aio request immediately. */ if (priv->to_free == NULL || unlikely(req->actual == 0)) { kfree(req->buf); kfree(priv->to_free); kfree(priv); iocb->private = NULL; /* aio_complete() reports bytes-transferred _and_ faults */ iocb->ki_complete(iocb, req->actual ? req->actual : req->status, req->status); } else { /* ep_copy_to_user() won't report both; we hide some faults */ if (unlikely(0 != req->status)) DBG(epdata->dev, "%s fault %d len %d\n", ep->name, req->status, req->actual); priv->buf = req->buf; priv->actual = req->actual; INIT_WORK(&priv->work, ep_user_copy_worker); schedule_work(&priv->work); } usb_ep_free_request(ep, req); spin_unlock(&epdata->dev->lock); put_ep(epdata); } static ssize_t ep_aio(struct kiocb *iocb, struct kiocb_priv *priv, struct ep_data *epdata, char *buf, size_t len) { struct usb_request *req; ssize_t value; iocb->private = priv; priv->iocb = iocb; kiocb_set_cancel_fn(iocb, ep_aio_cancel); get_ep(epdata); priv->epdata = epdata; priv->actual = 0; priv->mm = current->mm; /* mm teardown waits for iocbs in exit_aio() */ /* each kiocb is coupled to one usb_request, but we can't * allocate or submit those if the host disconnected. */ spin_lock_irq(&epdata->dev->lock); value = -ENODEV; if (unlikely(epdata->ep == NULL)) goto fail; req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC); value = -ENOMEM; if (unlikely(!req)) goto fail; priv->req = req; req->buf = buf; req->length = len; req->complete = ep_aio_complete; req->context = iocb; value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC); if (unlikely(0 != value)) { usb_ep_free_request(epdata->ep, req); goto fail; } spin_unlock_irq(&epdata->dev->lock); return -EIOCBQUEUED; fail: spin_unlock_irq(&epdata->dev->lock); kfree(priv->to_free); kfree(priv); put_ep(epdata); return value; } static ssize_t ep_read_iter(struct kiocb *iocb, struct iov_iter *to) { struct file *file = iocb->ki_filp; struct ep_data *epdata = file->private_data; size_t len = iov_iter_count(to); ssize_t value; char *buf; if ((value = get_ready_ep(file->f_flags, epdata, false)) < 0) return value; /* halt any endpoint by doing a "wrong direction" i/o call */ if (usb_endpoint_dir_in(&epdata->desc)) { if (usb_endpoint_xfer_isoc(&epdata->desc) || !is_sync_kiocb(iocb)) { mutex_unlock(&epdata->lock); return -EINVAL; } DBG (epdata->dev, "%s halt\n", epdata->name); spin_lock_irq(&epdata->dev->lock); if (likely(epdata->ep != NULL)) usb_ep_set_halt(epdata->ep); spin_unlock_irq(&epdata->dev->lock); mutex_unlock(&epdata->lock); return -EBADMSG; } buf = kmalloc(len, GFP_KERNEL); if (unlikely(!buf)) { mutex_unlock(&epdata->lock); return -ENOMEM; } if (is_sync_kiocb(iocb)) { value = ep_io(epdata, buf, len); if (value >= 0 && (copy_to_iter(buf, value, to) != value)) value = -EFAULT; } else { struct kiocb_priv *priv = kzalloc(sizeof *priv, GFP_KERNEL); value = -ENOMEM; if (!priv) goto fail; priv->to_free = dup_iter(&priv->to, to, GFP_KERNEL); if (!priv->to_free) { kfree(priv); goto fail; } value = ep_aio(iocb, priv, epdata, buf, len); if (value == -EIOCBQUEUED) buf = NULL; } fail: kfree(buf); mutex_unlock(&epdata->lock); return value; } static ssize_t ep_config(struct ep_data *, const char *, size_t); static ssize_t ep_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; struct ep_data *epdata = file->private_data; size_t len = iov_iter_count(from); bool configured; ssize_t value; char *buf; if ((value = get_ready_ep(file->f_flags, epdata, true)) < 0) return value; configured = epdata->state == STATE_EP_ENABLED; /* halt any endpoint by doing a "wrong direction" i/o call */ if (configured && !usb_endpoint_dir_in(&epdata->desc)) { if (usb_endpoint_xfer_isoc(&epdata->desc) || !is_sync_kiocb(iocb)) { mutex_unlock(&epdata->lock); return -EINVAL; } DBG (epdata->dev, "%s halt\n", epdata->name); spin_lock_irq(&epdata->dev->lock); if (likely(epdata->ep != NULL)) usb_ep_set_halt(epdata->ep); spin_unlock_irq(&epdata->dev->lock); mutex_unlock(&epdata->lock); return -EBADMSG; } buf = kmalloc(len, GFP_KERNEL); if (unlikely(!buf)) { mutex_unlock(&epdata->lock); return -ENOMEM; } if (unlikely(!copy_from_iter_full(buf, len, from))) { value = -EFAULT; goto out; } if (unlikely(!configured)) { value = ep_config(epdata, buf, len); } else if (is_sync_kiocb(iocb)) { value = ep_io(epdata, buf, len); } else { struct kiocb_priv *priv = kzalloc(sizeof *priv, GFP_KERNEL); value = -ENOMEM; if (priv) { value = ep_aio(iocb, priv, epdata, buf, len); if (value == -EIOCBQUEUED) buf = NULL; } } out: kfree(buf); mutex_unlock(&epdata->lock); return value; } /*----------------------------------------------------------------------*/ /* used after endpoint configuration */ static const struct file_operations ep_io_operations = { .owner = THIS_MODULE, .open = ep_open, .release = ep_release, .llseek = no_llseek, .unlocked_ioctl = ep_ioctl, .read_iter = ep_read_iter, .write_iter = ep_write_iter, }; /* ENDPOINT INITIALIZATION * * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR) * status = write (fd, descriptors, sizeof descriptors) * * That write establishes the endpoint configuration, configuring * the controller to process bulk, interrupt, or isochronous transfers * at the right maxpacket size, and so on. * * The descriptors are message type 1, identified by a host order u32 * at the beginning of what's written. Descriptor order is: full/low * speed descriptor, then optional high speed descriptor. */ static ssize_t ep_config (struct ep_data *data, const char *buf, size_t len) { struct usb_ep *ep; u32 tag; int value, length = len; if (data->state != STATE_EP_READY) { value = -EL2HLT; goto fail; } value = len; if (len < USB_DT_ENDPOINT_SIZE + 4) goto fail0; /* we might need to change message format someday */ memcpy(&tag, buf, 4); if (tag != 1) { DBG(data->dev, "config %s, bad tag %d\n", data->name, tag); goto fail0; } buf += 4; len -= 4; /* NOTE: audio endpoint extensions not accepted here; * just don't include the extra bytes. */ /* full/low speed descriptor, then high speed */ memcpy(&data->desc, buf, USB_DT_ENDPOINT_SIZE); if (data->desc.bLength != USB_DT_ENDPOINT_SIZE || data->desc.bDescriptorType != USB_DT_ENDPOINT) goto fail0; if (len != USB_DT_ENDPOINT_SIZE) { if (len != 2 * USB_DT_ENDPOINT_SIZE) goto fail0; memcpy(&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE, USB_DT_ENDPOINT_SIZE); if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE || data->hs_desc.bDescriptorType != USB_DT_ENDPOINT) { DBG(data->dev, "config %s, bad hs length or type\n", data->name); goto fail0; } } spin_lock_irq (&data->dev->lock); if (data->dev->state == STATE_DEV_UNBOUND) { value = -ENOENT; goto gone; } else { ep = data->ep; if (ep == NULL) { value = -ENODEV; goto gone; } } switch (data->dev->gadget->speed) { case USB_SPEED_LOW: case USB_SPEED_FULL: ep->desc = &data->desc; break; case USB_SPEED_HIGH: /* fails if caller didn't provide that descriptor... */ ep->desc = &data->hs_desc; break; default: DBG(data->dev, "unconnected, %s init abandoned\n", data->name); value = -EINVAL; goto gone; } value = usb_ep_enable(ep); if (value == 0) { data->state = STATE_EP_ENABLED; value = length; } gone: spin_unlock_irq (&data->dev->lock); if (value < 0) { fail: data->desc.bDescriptorType = 0; data->hs_desc.bDescriptorType = 0; } return value; fail0: value = -EINVAL; goto fail; } static int ep_open (struct inode *inode, struct file *fd) { struct ep_data *data = inode->i_private; int value = -EBUSY; if (mutex_lock_interruptible(&data->lock) != 0) return -EINTR; spin_lock_irq (&data->dev->lock); if (data->dev->state == STATE_DEV_UNBOUND) value = -ENOENT; else if (data->state == STATE_EP_DISABLED) { value = 0; data->state = STATE_EP_READY; get_ep (data); fd->private_data = data; VDEBUG (data->dev, "%s ready\n", data->name); } else DBG (data->dev, "%s state %d\n", data->name, data->state); spin_unlock_irq (&data->dev->lock); mutex_unlock(&data->lock); return value; } /*----------------------------------------------------------------------*/ /* EP0 IMPLEMENTATION can be partly in userspace. * * Drivers that use this facility receive various events, including * control requests the kernel doesn't handle. Drivers that don't * use this facility may be too simple-minded for real applications. */ static inline void ep0_readable (struct dev_data *dev) { wake_up (&dev->wait); kill_fasync (&dev->fasync, SIGIO, POLL_IN); } static void clean_req (struct usb_ep *ep, struct usb_request *req) { struct dev_data *dev = ep->driver_data; if (req->buf != dev->rbuf) { kfree(req->buf); req->buf = dev->rbuf; } req->complete = epio_complete; dev->setup_out_ready = 0; } static void ep0_complete (struct usb_ep *ep, struct usb_request *req) { struct dev_data *dev = ep->driver_data; unsigned long flags; int free = 1; /* for control OUT, data must still get to userspace */ spin_lock_irqsave(&dev->lock, flags); if (!dev->setup_in) { dev->setup_out_error = (req->status != 0); if (!dev->setup_out_error) free = 0; dev->setup_out_ready = 1; ep0_readable (dev); } /* clean up as appropriate */ if (free && req->buf != &dev->rbuf) clean_req (ep, req); req->complete = epio_complete; spin_unlock_irqrestore(&dev->lock, flags); } static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len) { struct dev_data *dev = ep->driver_data; if (dev->setup_out_ready) { DBG (dev, "ep0 request busy!\n"); return -EBUSY; } if (len > sizeof (dev->rbuf)) req->buf = kmalloc(len, GFP_ATOMIC); if (req->buf == NULL) { req->buf = dev->rbuf; return -ENOMEM; } req->complete = ep0_complete; req->length = len; req->zero = 0; return 0; } static ssize_t ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr) { struct dev_data *dev = fd->private_data; ssize_t retval; enum ep0_state state; spin_lock_irq (&dev->lock); if (dev->state <= STATE_DEV_OPENED) { retval = -EINVAL; goto done; } /* report fd mode change before acting on it */ if (dev->setup_abort) { dev->setup_abort = 0; retval = -EIDRM; goto done; } /* control DATA stage */ if ((state = dev->state) == STATE_DEV_SETUP) { if (dev->setup_in) { /* stall IN */ VDEBUG(dev, "ep0in stall\n"); (void) usb_ep_set_halt (dev->gadget->ep0); retval = -EL2HLT; dev->state = STATE_DEV_CONNECTED; } else if (len == 0) { /* ack SET_CONFIGURATION etc */ struct usb_ep *ep = dev->gadget->ep0; struct usb_request *req = dev->req; if ((retval = setup_req (ep, req, 0)) == 0) { ++dev->udc_usage; spin_unlock_irq (&dev->lock); retval = usb_ep_queue (ep, req, GFP_KERNEL); spin_lock_irq (&dev->lock); --dev->udc_usage; } dev->state = STATE_DEV_CONNECTED; /* assume that was SET_CONFIGURATION */ if (dev->current_config) { unsigned power; if (gadget_is_dualspeed(dev->gadget) && (dev->gadget->speed == USB_SPEED_HIGH)) power = dev->hs_config->bMaxPower; else power = dev->config->bMaxPower; usb_gadget_vbus_draw(dev->gadget, 2 * power); } } else { /* collect OUT data */ if ((fd->f_flags & O_NONBLOCK) != 0 && !dev->setup_out_ready) { retval = -EAGAIN; goto done; } spin_unlock_irq (&dev->lock); retval = wait_event_interruptible (dev->wait, dev->setup_out_ready != 0); /* FIXME state could change from under us */ spin_lock_irq (&dev->lock); if (retval) goto done; if (dev->state != STATE_DEV_SETUP) { retval = -ECANCELED; goto done; } dev->state = STATE_DEV_CONNECTED; if (dev->setup_out_error) retval = -EIO; else { len = min (len, (size_t)dev->req->actual); ++dev->udc_usage; spin_unlock_irq(&dev->lock); if (copy_to_user (buf, dev->req->buf, len)) retval = -EFAULT; else retval = len; spin_lock_irq(&dev->lock); --dev->udc_usage; clean_req (dev->gadget->ep0, dev->req); /* NOTE userspace can't yet choose to stall */ } } goto done; } /* else normal: return event data */ if (len < sizeof dev->event [0]) { retval = -EINVAL; goto done; } len -= len % sizeof (struct usb_gadgetfs_event); dev->usermode_setup = 1; scan: /* return queued events right away */ if (dev->ev_next != 0) { unsigned i, n; n = len / sizeof (struct usb_gadgetfs_event); if (dev->ev_next < n) n = dev->ev_next; /* ep0 i/o has special semantics during STATE_DEV_SETUP */ for (i = 0; i < n; i++) { if (dev->event [i].type == GADGETFS_SETUP) { dev->state = STATE_DEV_SETUP; n = i + 1; break; } } spin_unlock_irq (&dev->lock); len = n * sizeof (struct usb_gadgetfs_event); if (copy_to_user (buf, &dev->event, len)) retval = -EFAULT; else retval = len; if (len > 0) { /* NOTE this doesn't guard against broken drivers; * concurrent ep0 readers may lose events. */ spin_lock_irq (&dev->lock); if (dev->ev_next > n) { memmove(&dev->event[0], &dev->event[n], sizeof (struct usb_gadgetfs_event) * (dev->ev_next - n)); } dev->ev_next -= n; spin_unlock_irq (&dev->lock); } return retval; } if (fd->f_flags & O_NONBLOCK) { retval = -EAGAIN; goto done; } switch (state) { default: DBG (dev, "fail %s, state %d\n", __func__, state); retval = -ESRCH; break; case STATE_DEV_UNCONNECTED: case STATE_DEV_CONNECTED: spin_unlock_irq (&dev->lock); DBG (dev, "%s wait\n", __func__); /* wait for events */ retval = wait_event_interruptible (dev->wait, dev->ev_next != 0); if (retval < 0) return retval; spin_lock_irq (&dev->lock); goto scan; } done: spin_unlock_irq (&dev->lock); return retval; } static struct usb_gadgetfs_event * next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type) { struct usb_gadgetfs_event *event; unsigned i; switch (type) { /* these events purge the queue */ case GADGETFS_DISCONNECT: if (dev->state == STATE_DEV_SETUP) dev->setup_abort = 1; // FALL THROUGH case GADGETFS_CONNECT: dev->ev_next = 0; break; case GADGETFS_SETUP: /* previous request timed out */ case GADGETFS_SUSPEND: /* same effect */ /* these events can't be repeated */ for (i = 0; i != dev->ev_next; i++) { if (dev->event [i].type != type) continue; DBG(dev, "discard old event[%d] %d\n", i, type); dev->ev_next--; if (i == dev->ev_next) break; /* indices start at zero, for simplicity */ memmove (&dev->event [i], &dev->event [i + 1], sizeof (struct usb_gadgetfs_event) * (dev->ev_next - i)); } break; default: BUG (); } VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type); event = &dev->event [dev->ev_next++]; BUG_ON (dev->ev_next > N_EVENT); memset (event, 0, sizeof *event); event->type = type; return event; } static ssize_t ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) { struct dev_data *dev = fd->private_data; ssize_t retval = -ESRCH; /* report fd mode change before acting on it */ if (dev->setup_abort) { dev->setup_abort = 0; retval = -EIDRM; /* data and/or status stage for control request */ } else if (dev->state == STATE_DEV_SETUP) { len = min_t(size_t, len, dev->setup_wLength); if (dev->setup_in) { retval = setup_req (dev->gadget->ep0, dev->req, len); if (retval == 0) { dev->state = STATE_DEV_CONNECTED; ++dev->udc_usage; spin_unlock_irq (&dev->lock); if (copy_from_user (dev->req->buf, buf, len)) retval = -EFAULT; else { if (len < dev->setup_wLength) dev->req->zero = 1; retval = usb_ep_queue ( dev->gadget->ep0, dev->req, GFP_KERNEL); } spin_lock_irq(&dev->lock); --dev->udc_usage; if (retval < 0) { clean_req (dev->gadget->ep0, dev->req); } else retval = len; return retval; } /* can stall some OUT transfers */ } else if (dev->setup_can_stall) { VDEBUG(dev, "ep0out stall\n"); (void) usb_ep_set_halt (dev->gadget->ep0); retval = -EL2HLT; dev->state = STATE_DEV_CONNECTED; } else { DBG(dev, "bogus ep0out stall!\n"); } } else DBG (dev, "fail %s, state %d\n", __func__, dev->state); return retval; } static int ep0_fasync (int f, struct file *fd, int on) { struct dev_data *dev = fd->private_data; // caller must F_SETOWN before signal delivery happens VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off"); return fasync_helper (f, fd, on, &dev->fasync); } static struct usb_gadget_driver gadgetfs_driver; static int dev_release (struct inode *inode, struct file *fd) { struct dev_data *dev = fd->private_data; /* closing ep0 === shutdown all */ if (dev->gadget_registered) { usb_gadget_unregister_driver (&gadgetfs_driver); dev->gadget_registered = false; } /* at this point "good" hardware has disconnected the * device from USB; the host won't see it any more. * alternatively, all host requests will time out. */ kfree (dev->buf); dev->buf = NULL; /* other endpoints were all decoupled from this device */ spin_lock_irq(&dev->lock); dev->state = STATE_DEV_DISABLED; spin_unlock_irq(&dev->lock); put_dev (dev); return 0; } static __poll_t ep0_poll (struct file *fd, poll_table *wait) { struct dev_data *dev = fd->private_data; __poll_t mask = 0; if (dev->state <= STATE_DEV_OPENED) return DEFAULT_POLLMASK; poll_wait(fd, &dev->wait, wait); spin_lock_irq(&dev->lock); /* report fd mode change before acting on it */ if (dev->setup_abort) { dev->setup_abort = 0; mask = EPOLLHUP; goto out; } if (dev->state == STATE_DEV_SETUP) { if (dev->setup_in || dev->setup_can_stall) mask = EPOLLOUT; } else { if (dev->ev_next != 0) mask = EPOLLIN; } out: spin_unlock_irq(&dev->lock); return mask; } static long dev_ioctl (struct file *fd, unsigned code, unsigned long value) { struct dev_data *dev = fd->private_data; struct usb_gadget *gadget = dev->gadget; long ret = -ENOTTY; spin_lock_irq(&dev->lock); if (dev->state == STATE_DEV_OPENED || dev->state == STATE_DEV_UNBOUND) { /* Not bound to a UDC */ } else if (gadget->ops->ioctl) { ++dev->udc_usage; spin_unlock_irq(&dev->lock); ret = gadget->ops->ioctl (gadget, code, value); spin_lock_irq(&dev->lock); --dev->udc_usage; } spin_unlock_irq(&dev->lock); return ret; } /*----------------------------------------------------------------------*/ /* The in-kernel gadget driver handles most ep0 issues, in particular * enumerating the single configuration (as provided from user space). * * Unrecognized ep0 requests may be handled in user space. */ static void make_qualifier (struct dev_data *dev) { struct usb_qualifier_descriptor qual; struct usb_device_descriptor *desc; qual.bLength = sizeof qual; qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER; qual.bcdUSB = cpu_to_le16 (0x0200); desc = dev->dev; qual.bDeviceClass = desc->bDeviceClass; qual.bDeviceSubClass = desc->bDeviceSubClass; qual.bDeviceProtocol = desc->bDeviceProtocol; /* assumes ep0 uses the same value for both speeds ... */ qual.bMaxPacketSize0 = dev->gadget->ep0->maxpacket; qual.bNumConfigurations = 1; qual.bRESERVED = 0; memcpy (dev->rbuf, &qual, sizeof qual); } static int config_buf (struct dev_data *dev, u8 type, unsigned index) { int len; int hs = 0; /* only one configuration */ if (index > 0) return -EINVAL; if (gadget_is_dualspeed(dev->gadget)) { hs = (dev->gadget->speed == USB_SPEED_HIGH); if (type == USB_DT_OTHER_SPEED_CONFIG) hs = !hs; } if (hs) { dev->req->buf = dev->hs_config; len = le16_to_cpu(dev->hs_config->wTotalLength); } else { dev->req->buf = dev->config; len = le16_to_cpu(dev->config->wTotalLength); } ((u8 *)dev->req->buf) [1] = type; return len; } static int gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) { struct dev_data *dev = get_gadget_data (gadget); struct usb_request *req = dev->req; int value = -EOPNOTSUPP; struct usb_gadgetfs_event *event; u16 w_value = le16_to_cpu(ctrl->wValue); u16 w_length = le16_to_cpu(ctrl->wLength); spin_lock (&dev->lock); dev->setup_abort = 0; if (dev->state == STATE_DEV_UNCONNECTED) { if (gadget_is_dualspeed(gadget) && gadget->speed == USB_SPEED_HIGH && dev->hs_config == NULL) { spin_unlock(&dev->lock); ERROR (dev, "no high speed config??\n"); return -EINVAL; } dev->state = STATE_DEV_CONNECTED; INFO (dev, "connected\n"); event = next_event (dev, GADGETFS_CONNECT); event->u.speed = gadget->speed; ep0_readable (dev); /* host may have given up waiting for response. we can miss control * requests handled lower down (device/endpoint status and features); * then ep0_{read,write} will report the wrong status. controller * driver will have aborted pending i/o. */ } else if (dev->state == STATE_DEV_SETUP) dev->setup_abort = 1; req->buf = dev->rbuf; req->context = NULL; value = -EOPNOTSUPP; switch (ctrl->bRequest) { case USB_REQ_GET_DESCRIPTOR: if (ctrl->bRequestType != USB_DIR_IN) goto unrecognized; switch (w_value >> 8) { case USB_DT_DEVICE: value = min (w_length, (u16) sizeof *dev->dev); dev->dev->bMaxPacketSize0 = dev->gadget->ep0->maxpacket; req->buf = dev->dev; break; case USB_DT_DEVICE_QUALIFIER: if (!dev->hs_config) break; value = min (w_length, (u16) sizeof (struct usb_qualifier_descriptor)); make_qualifier (dev); break; case USB_DT_OTHER_SPEED_CONFIG: // FALLTHROUGH case USB_DT_CONFIG: value = config_buf (dev, w_value >> 8, w_value & 0xff); if (value >= 0) value = min (w_length, (u16) value); break; case USB_DT_STRING: goto unrecognized; default: // all others are errors break; } break; /* currently one config, two speeds */ case USB_REQ_SET_CONFIGURATION: if (ctrl->bRequestType != 0) goto unrecognized; if (0 == (u8) w_value) { value = 0; dev->current_config = 0; usb_gadget_vbus_draw(gadget, 8 /* mA */ ); // user mode expected to disable endpoints } else { u8 config, power; if (gadget_is_dualspeed(gadget) && gadget->speed == USB_SPEED_HIGH) { config = dev->hs_config->bConfigurationValue; power = dev->hs_config->bMaxPower; } else { config = dev->config->bConfigurationValue; power = dev->config->bMaxPower; } if (config == (u8) w_value) { value = 0; dev->current_config = config; usb_gadget_vbus_draw(gadget, 2 * power); } } /* report SET_CONFIGURATION like any other control request, * except that usermode may not stall this. the next * request mustn't be allowed start until this finishes: * endpoints and threads set up, etc. * * NOTE: older PXA hardware (before PXA 255: without UDCCFR) * has bad/racey automagic that prevents synchronizing here. * even kernel mode drivers often miss them. */ if (value == 0) { INFO (dev, "configuration #%d\n", dev->current_config); usb_gadget_set_state(gadget, USB_STATE_CONFIGURED); if (dev->usermode_setup) { dev->setup_can_stall = 0; goto delegate; } } break; #ifndef CONFIG_USB_PXA25X /* PXA automagically handles this request too */ case USB_REQ_GET_CONFIGURATION: if (ctrl->bRequestType != 0x80) goto unrecognized; *(u8 *)req->buf = dev->current_config; value = min (w_length, (u16) 1); break; #endif default: unrecognized: VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n", dev->usermode_setup ? "delegate" : "fail", ctrl->bRequestType, ctrl->bRequest, w_value, le16_to_cpu(ctrl->wIndex), w_length); /* if there's an ep0 reader, don't stall */ if (dev->usermode_setup) { dev->setup_can_stall = 1; delegate: dev->setup_in = (ctrl->bRequestType & USB_DIR_IN) ? 1 : 0; dev->setup_wLength = w_length; dev->setup_out_ready = 0; dev->setup_out_error = 0; /* read DATA stage for OUT right away */ if (unlikely (!dev->setup_in && w_length)) { value = setup_req (gadget->ep0, dev->req, w_length); if (value < 0) break; ++dev->udc_usage; spin_unlock (&dev->lock); value = usb_ep_queue (gadget->ep0, dev->req, GFP_KERNEL); spin_lock (&dev->lock); --dev->udc_usage; if (value < 0) { clean_req (gadget->ep0, dev->req); break; } /* we can't currently stall these */ dev->setup_can_stall = 0; } /* state changes when reader collects event */ event = next_event (dev, GADGETFS_SETUP); event->u.setup = *ctrl; ep0_readable (dev); spin_unlock (&dev->lock); return 0; } } /* proceed with data transfer and status phases? */ if (value >= 0 && dev->state != STATE_DEV_SETUP) { req->length = value; req->zero = value < w_length; ++dev->udc_usage; spin_unlock (&dev->lock); value = usb_ep_queue (gadget->ep0, req, GFP_KERNEL); spin_lock(&dev->lock); --dev->udc_usage; spin_unlock(&dev->lock); if (value < 0) { DBG (dev, "ep_queue --> %d\n", value); req->status = 0; } return value; } /* device stalls when value < 0 */ spin_unlock (&dev->lock); return value; } static void destroy_ep_files (struct dev_data *dev) { DBG (dev, "%s %d\n", __func__, dev->state); /* dev->state must prevent interference */ spin_lock_irq (&dev->lock); while (!list_empty(&dev->epfiles)) { struct ep_data *ep; struct inode *parent; struct dentry *dentry; /* break link to FS */ ep = list_first_entry (&dev->epfiles, struct ep_data, epfiles); list_del_init (&ep->epfiles); spin_unlock_irq (&dev->lock); dentry = ep->dentry; ep->dentry = NULL; parent = d_inode(dentry->d_parent); /* break link to controller */ mutex_lock(&ep->lock); if (ep->state == STATE_EP_ENABLED) (void) usb_ep_disable (ep->ep); ep->state = STATE_EP_UNBOUND; usb_ep_free_request (ep->ep, ep->req); ep->ep = NULL; mutex_unlock(&ep->lock); wake_up (&ep->wait); put_ep (ep); /* break link to dcache */ inode_lock(parent); d_delete (dentry); dput (dentry); inode_unlock(parent); spin_lock_irq (&dev->lock); } spin_unlock_irq (&dev->lock); } static struct dentry * gadgetfs_create_file (struct super_block *sb, char const *name, void *data, const struct file_operations *fops); static int activate_ep_files (struct dev_data *dev) { struct usb_ep *ep; struct ep_data *data; gadget_for_each_ep (ep, dev->gadget) { data = kzalloc(sizeof(*data), GFP_KERNEL); if (!data) goto enomem0; data->state = STATE_EP_DISABLED; mutex_init(&data->lock); init_waitqueue_head (&data->wait); strncpy (data->name, ep->name, sizeof (data->name) - 1); refcount_set (&data->count, 1); data->dev = dev; get_dev (dev); data->ep = ep; ep->driver_data = data; data->req = usb_ep_alloc_request (ep, GFP_KERNEL); if (!data->req) goto enomem1; data->dentry = gadgetfs_create_file (dev->sb, data->name, data, &ep_io_operations); if (!data->dentry) goto enomem2; list_add_tail (&data->epfiles, &dev->epfiles); } return 0; enomem2: usb_ep_free_request (ep, data->req); enomem1: put_dev (dev); kfree (data); enomem0: DBG (dev, "%s enomem\n", __func__); destroy_ep_files (dev); return -ENOMEM; } static void gadgetfs_unbind (struct usb_gadget *gadget) { struct dev_data *dev = get_gadget_data (gadget); DBG (dev, "%s\n", __func__); spin_lock_irq (&dev->lock); dev->state = STATE_DEV_UNBOUND; while (dev->udc_usage > 0) { spin_unlock_irq(&dev->lock); usleep_range(1000, 2000); spin_lock_irq(&dev->lock); } spin_unlock_irq (&dev->lock); destroy_ep_files (dev); gadget->ep0->driver_data = NULL; set_gadget_data (gadget, NULL); /* we've already been disconnected ... no i/o is active */ if (dev->req) usb_ep_free_request (gadget->ep0, dev->req); DBG (dev, "%s done\n", __func__); put_dev (dev); } static struct dev_data *the_device; static int gadgetfs_bind(struct usb_gadget *gadget, struct usb_gadget_driver *driver) { struct dev_data *dev = the_device; if (!dev) return -ESRCH; if (0 != strcmp (CHIP, gadget->name)) { pr_err("%s expected %s controller not %s\n", shortname, CHIP, gadget->name); return -ENODEV; } set_gadget_data (gadget, dev); dev->gadget = gadget; gadget->ep0->driver_data = dev; /* preallocate control response and buffer */ dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL); if (!dev->req) goto enomem; dev->req->context = NULL; dev->req->complete = epio_complete; if (activate_ep_files (dev) < 0) goto enomem; INFO (dev, "bound to %s driver\n", gadget->name); spin_lock_irq(&dev->lock); dev->state = STATE_DEV_UNCONNECTED; spin_unlock_irq(&dev->lock); get_dev (dev); return 0; enomem: gadgetfs_unbind (gadget); return -ENOMEM; } static void gadgetfs_disconnect (struct usb_gadget *gadget) { struct dev_data *dev = get_gadget_data (gadget); unsigned long flags; spin_lock_irqsave (&dev->lock, flags); if (dev->state == STATE_DEV_UNCONNECTED) goto exit; dev->state = STATE_DEV_UNCONNECTED; INFO (dev, "disconnected\n"); next_event (dev, GADGETFS_DISCONNECT); ep0_readable (dev); exit: spin_unlock_irqrestore (&dev->lock, flags); } static void gadgetfs_suspend (struct usb_gadget *gadget) { struct dev_data *dev = get_gadget_data (gadget); unsigned long flags; INFO (dev, "suspended from state %d\n", dev->state); spin_lock_irqsave(&dev->lock, flags); switch (dev->state) { case STATE_DEV_SETUP: // VERY odd... host died?? case STATE_DEV_CONNECTED: case STATE_DEV_UNCONNECTED: next_event (dev, GADGETFS_SUSPEND); ep0_readable (dev); /* FALLTHROUGH */ default: break; } spin_unlock_irqrestore(&dev->lock, flags); } static struct usb_gadget_driver gadgetfs_driver = { .function = (char *) driver_desc, .bind = gadgetfs_bind, .unbind = gadgetfs_unbind, .setup = gadgetfs_setup, .reset = gadgetfs_disconnect, .disconnect = gadgetfs_disconnect, .suspend = gadgetfs_suspend, .driver = { .name = (char *) shortname, }, }; /*----------------------------------------------------------------------*/ /* DEVICE INITIALIZATION * * fd = open ("/dev/gadget/$CHIP", O_RDWR) * status = write (fd, descriptors, sizeof descriptors) * * That write establishes the device configuration, so the kernel can * bind to the controller ... guaranteeing it can handle enumeration * at all necessary speeds. Descriptor order is: * * . message tag (u32, host order) ... for now, must be zero; it * would change to support features like multi-config devices * . full/low speed config ... all wTotalLength bytes (with interface, * class, altsetting, endpoint, and other descriptors) * . high speed config ... all descriptors, for high speed operation; * this one's optional except for high-speed hardware * . device descriptor * * Endpoints are not yet enabled. Drivers must wait until device * configuration and interface altsetting changes create * the need to configure (or unconfigure) them. * * After initialization, the device stays active for as long as that * $CHIP file is open. Events must then be read from that descriptor, * such as configuration notifications. */ static int is_valid_config(struct usb_config_descriptor *config, unsigned int total) { return config->bDescriptorType == USB_DT_CONFIG && config->bLength == USB_DT_CONFIG_SIZE && total >= USB_DT_CONFIG_SIZE && config->bConfigurationValue != 0 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0; /* FIXME if gadget->is_otg, _must_ include an otg descriptor */ /* FIXME check lengths: walk to end */ } static ssize_t dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) { struct dev_data *dev = fd->private_data; ssize_t value = len, length = len; unsigned total; u32 tag; char *kbuf; spin_lock_irq(&dev->lock); if (dev->state > STATE_DEV_OPENED) { value = ep0_write(fd, buf, len, ptr); spin_unlock_irq(&dev->lock); return value; } spin_unlock_irq(&dev->lock); if ((len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4)) || (len > PAGE_SIZE * 4)) return -EINVAL; /* we might need to change message format someday */ if (copy_from_user (&tag, buf, 4)) return -EFAULT; if (tag != 0) return -EINVAL; buf += 4; length -= 4; kbuf = memdup_user(buf, length); if (IS_ERR(kbuf)) return PTR_ERR(kbuf); spin_lock_irq (&dev->lock); value = -EINVAL; if (dev->buf) { kfree(kbuf); goto fail; } dev->buf = kbuf; /* full or low speed config */ dev->config = (void *) kbuf; total = le16_to_cpu(dev->config->wTotalLength); if (!is_valid_config(dev->config, total) || total > length - USB_DT_DEVICE_SIZE) goto fail; kbuf += total; length -= total; /* optional high speed config */ if (kbuf [1] == USB_DT_CONFIG) { dev->hs_config = (void *) kbuf; total = le16_to_cpu(dev->hs_config->wTotalLength); if (!is_valid_config(dev->hs_config, total) || total > length - USB_DT_DEVICE_SIZE) goto fail; kbuf += total; length -= total; } else { dev->hs_config = NULL; } /* could support multiple configs, using another encoding! */ /* device descriptor (tweaked for paranoia) */ if (length != USB_DT_DEVICE_SIZE) goto fail; dev->dev = (void *)kbuf; if (dev->dev->bLength != USB_DT_DEVICE_SIZE || dev->dev->bDescriptorType != USB_DT_DEVICE || dev->dev->bNumConfigurations != 1) goto fail; dev->dev->bcdUSB = cpu_to_le16 (0x0200); /* triggers gadgetfs_bind(); then we can enumerate. */ spin_unlock_irq (&dev->lock); if (dev->hs_config) gadgetfs_driver.max_speed = USB_SPEED_HIGH; else gadgetfs_driver.max_speed = USB_SPEED_FULL; value = usb_gadget_probe_driver(&gadgetfs_driver); if (value != 0) { kfree (dev->buf); dev->buf = NULL; } else { /* at this point "good" hardware has for the first time * let the USB the host see us. alternatively, if users * unplug/replug that will clear all the error state. * * note: everything running before here was guaranteed * to choke driver model style diagnostics. from here * on, they can work ... except in cleanup paths that * kick in after the ep0 descriptor is closed. */ value = len; dev->gadget_registered = true; } return value; fail: spin_unlock_irq (&dev->lock); pr_debug ("%s: %s fail %zd, %p\n", shortname, __func__, value, dev); kfree (dev->buf); dev->buf = NULL; return value; } static int dev_open (struct inode *inode, struct file *fd) { struct dev_data *dev = inode->i_private; int value = -EBUSY; spin_lock_irq(&dev->lock); if (dev->state == STATE_DEV_DISABLED) { dev->ev_next = 0; dev->state = STATE_DEV_OPENED; fd->private_data = dev; get_dev (dev); value = 0; } spin_unlock_irq(&dev->lock); return value; } static const struct file_operations ep0_operations = { .llseek = no_llseek, .open = dev_open, .read = ep0_read, .write = dev_config, .fasync = ep0_fasync, .poll = ep0_poll, .unlocked_ioctl = dev_ioctl, .release = dev_release, }; /*----------------------------------------------------------------------*/ /* FILESYSTEM AND SUPERBLOCK OPERATIONS * * Mounting the filesystem creates a controller file, used first for * device configuration then later for event monitoring. */ /* FIXME PAM etc could set this security policy without mount options * if epfiles inherited ownership and permissons from ep0 ... */ static unsigned default_uid; static unsigned default_gid; static unsigned default_perm = S_IRUSR | S_IWUSR; module_param (default_uid, uint, 0644); module_param (default_gid, uint, 0644); module_param (default_perm, uint, 0644); static struct inode * gadgetfs_make_inode (struct super_block *sb, void *data, const struct file_operations *fops, int mode) { struct inode *inode = new_inode (sb); if (inode) { inode->i_ino = get_next_ino(); inode->i_mode = mode; inode->i_uid = make_kuid(&init_user_ns, default_uid); inode->i_gid = make_kgid(&init_user_ns, default_gid); inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); inode->i_private = data; inode->i_fop = fops; } return inode; } /* creates in fs root directory, so non-renamable and non-linkable. * so inode and dentry are paired, until device reconfig. */ static struct dentry * gadgetfs_create_file (struct super_block *sb, char const *name, void *data, const struct file_operations *fops) { struct dentry *dentry; struct inode *inode; dentry = d_alloc_name(sb->s_root, name); if (!dentry) return NULL; inode = gadgetfs_make_inode (sb, data, fops, S_IFREG | (default_perm & S_IRWXUGO)); if (!inode) { dput(dentry); return NULL; } d_add (dentry, inode); return dentry; } static const struct super_operations gadget_fs_operations = { .statfs = simple_statfs, .drop_inode = generic_delete_inode, }; static int gadgetfs_fill_super (struct super_block *sb, void *opts, int silent) { struct inode *inode; struct dev_data *dev; if (the_device) return -ESRCH; CHIP = usb_get_gadget_udc_name(); if (!CHIP) return -ENODEV; /* superblock */ sb->s_blocksize = PAGE_SIZE; sb->s_blocksize_bits = PAGE_SHIFT; sb->s_magic = GADGETFS_MAGIC; sb->s_op = &gadget_fs_operations; sb->s_time_gran = 1; /* root inode */ inode = gadgetfs_make_inode (sb, NULL, &simple_dir_operations, S_IFDIR | S_IRUGO | S_IXUGO); if (!inode) goto Enomem; inode->i_op = &simple_dir_inode_operations; if (!(sb->s_root = d_make_root (inode))) goto Enomem; /* the ep0 file is named after the controller we expect; * user mode code can use it for sanity checks, like we do. */ dev = dev_new (); if (!dev) goto Enomem; dev->sb = sb; dev->dentry = gadgetfs_create_file(sb, CHIP, dev, &ep0_operations); if (!dev->dentry) { put_dev(dev); goto Enomem; } /* other endpoint files are available after hardware setup, * from binding to a controller. */ the_device = dev; return 0; Enomem: return -ENOMEM; } /* "mount -t gadgetfs path /dev/gadget" ends up here */ static struct dentry * gadgetfs_mount (struct file_system_type *t, int flags, const char *path, void *opts) { return mount_single (t, flags, opts, gadgetfs_fill_super); } static void gadgetfs_kill_sb (struct super_block *sb) { kill_litter_super (sb); if (the_device) { put_dev (the_device); the_device = NULL; } kfree(CHIP); CHIP = NULL; } /*----------------------------------------------------------------------*/ static struct file_system_type gadgetfs_type = { .owner = THIS_MODULE, .name = shortname, .mount = gadgetfs_mount, .kill_sb = gadgetfs_kill_sb, }; MODULE_ALIAS_FS("gadgetfs"); /*----------------------------------------------------------------------*/ static int __init init (void) { int status; status = register_filesystem (&gadgetfs_type); if (status == 0) pr_info ("%s: %s, version " DRIVER_VERSION "\n", shortname, driver_desc); return status; } module_init (init); static void __exit cleanup (void) { pr_debug ("unregister %s\n", shortname); unregister_filesystem (&gadgetfs_type); } module_exit (cleanup);
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