| /* |
| * inode.c -- user mode filesystem api for usb gadget controllers |
| * |
| * Copyright (C) 2003-2004 David Brownell |
| * Copyright (C) 2003 Agilent Technologies |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| */ |
| |
| |
| /* #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 <asm/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/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 { |
| /* DISBLED 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; |
| atomic_t count; |
| 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) |
| { |
| atomic_inc (&data->count); |
| } |
| |
| static void put_dev (struct dev_data *data) |
| { |
| if (likely (!atomic_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; |
| atomic_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; |
| atomic_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) |
| { |
| atomic_inc (&data->count); |
| } |
| |
| static void put_ep (struct ep_data *data) |
| { |
| if (likely (!atomic_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); |
| } |
| spin_unlock(&epdata->dev->lock); |
| |
| usb_ep_free_request(ep, req); |
| 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)) |
| 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 = -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(buf, len, from) != len)) { |
| 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) |
| retval = usb_ep_queue (ep, req, GFP_ATOMIC); |
| 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); |
| // FIXME don't call this with the spinlock held ... |
| if (copy_to_user (buf, dev->req->buf, len)) |
| retval = -EFAULT; |
| else |
| retval = len; |
| 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) { |
| |
| /* IN DATA+STATUS caller makes len <= wLength */ |
| if (dev->setup_in) { |
| retval = setup_req (dev->gadget->ep0, dev->req, len); |
| if (retval == 0) { |
| dev->state = STATE_DEV_CONNECTED; |
| 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); |
| 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); |
| |
| /* 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 unsigned int |
| ep0_poll (struct file *fd, poll_table *wait) |
| { |
| struct dev_data *dev = fd->private_data; |
| int 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 = POLLHUP; |
| goto out; |
| } |
| |
| if (dev->state == STATE_DEV_SETUP) { |
| if (dev->setup_in || dev->setup_can_stall) |
| mask = POLLOUT; |
| } else { |
| if (dev->ev_next != 0) |
| mask = POLLIN; |
| } |
| 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; |
| |
| if (gadget->ops->ioctl) |
| ret = gadget->ops->ioctl (gadget, code, value); |
| |
| 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; |
| value = 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; |
| value = usb_ep_queue (gadget->ep0, dev->req, |
| GFP_ATOMIC); |
| 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; |
| value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC); |
| if (value < 0) { |
| DBG (dev, "ep_queue --> %d\n", value); |
| req->status = 0; |
| } |
| } |
| |
| /* 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); |
| dentry = ep->dentry; |
| ep->dentry = NULL; |
| parent = d_inode(dentry->d_parent); |
| |
| /* break link to controller */ |
| 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; |
| wake_up (&ep->wait); |
| put_ep (ep); |
| |
| spin_unlock_irq (&dev->lock); |
| |
| /* 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); |
| atomic_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; |
| 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); |
| |
| INFO (dev, "suspended from state %d\n", dev->state); |
| spin_lock (&dev->lock); |
| 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 (&dev->lock); |
| } |
| |
| 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) |
| { |
| return config->bDescriptorType == USB_DT_CONFIG |
| && config->bLength == 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)) |
| 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) |
| 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 >= length) |
| 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 >= length) |
| goto fail; |
| kbuf += total; |
| length -= total; |
| } |
| |
| /* 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->bNumConfigurations = 1; |
| 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->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_CACHE_SIZE; |
| sb->s_blocksize_bits = PAGE_CACHE_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); |
| |