diff options
Diffstat (limited to 'drivers/usb/gadget/inode.c')
| -rw-r--r-- | drivers/usb/gadget/inode.c | 2110 |
1 files changed, 2110 insertions, 0 deletions
diff --git a/drivers/usb/gadget/inode.c b/drivers/usb/gadget/inode.c new file mode 100644 index 00000000000..2cff67ccce4 --- /dev/null +++ b/drivers/usb/gadget/inode.c @@ -0,0 +1,2110 @@ +/* + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + + +// #define DEBUG /* data to help fault diagnosis */ +// #define VERBOSE /* extra debug messages (success too) */ + +#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/slab.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/$CHIP is configured + * (by writing configuration and device descriptors). Afterwards it + * may serve as a source of device events, used to handle all control + * requests other than basic enumeration. + * + * - Then either immediately, or after a SET_CONFIGURATION control request, + * ep_config() is called when each /dev/gadget/ep* file is configured + * (by writing endpoint descriptors). Afterwards these files are used + * to write() IN data or to read() OUT data. To halt the endpoint, a + * "wrong direction" request is issued (like reading an IN endpoint). + * + * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe + * not possible on all hardware. For example, precise fault handling with + * respect to data left in endpoint fifos after aborted operations; or + * selective clearing of endpoint halts, to implement SET_INTERFACE. + */ + +#define DRIVER_DESC "USB Gadget filesystem" +#define DRIVER_VERSION "24 Aug 2004" + +static const char driver_desc [] = DRIVER_DESC; +static const char shortname [] = "gadgetfs"; + +MODULE_DESCRIPTION (DRIVER_DESC); +MODULE_AUTHOR ("David Brownell"); +MODULE_LICENSE ("GPL"); + + +/*----------------------------------------------------------------------*/ + +#define GADGETFS_MAGIC 0xaee71ee7 +#define DMA_ADDR_INVALID (~(dma_addr_t)0) + +/* /dev/gadget/$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_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_UNCONNECTED, + STATE_CONNECTED, + STATE_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; + 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; + + /* 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 = kmalloc (sizeof *dev, GFP_KERNEL); + if (!dev) + return NULL; + memset (dev, 0, sizeof *dev); + 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_DEFER_ENABLE, + STATE_EP_ENABLED, + STATE_EP_UNBOUND, +}; + +struct ep_data { + struct semaphore 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; + struct inode *inode; +}; + +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)); + BUG_ON (down_trylock (&data->lock) != 0); + 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 +#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 WARN(dev,fmt,args...) \ + xprintk(dev , KERN_WARNING , 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 cancelation. + */ + +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) +{ + int val; + + if (f_flags & O_NONBLOCK) { + if (down_trylock (&epdata->lock) != 0) + goto nonblock; + if (epdata->state != STATE_EP_ENABLED) { + up (&epdata->lock); +nonblock: + val = -EAGAIN; + } else + val = 0; + return val; + } + + if ((val = down_interruptible (&epdata->lock)) < 0) + return val; +newstate: + switch (epdata->state) { + case STATE_EP_ENABLED: + break; + case STATE_EP_DEFER_ENABLE: + DBG (epdata->dev, "%s wait for host\n", epdata->name); + if ((val = wait_event_interruptible (epdata->wait, + epdata->state != STATE_EP_DEFER_ENABLE + || epdata->dev->state == STATE_DEV_UNBOUND + )) < 0) + goto fail; + goto newstate; + // case STATE_EP_DISABLED: /* "can't happen" */ + // case STATE_EP_READY: /* "can't happen" */ + default: /* error! */ + pr_debug ("%s: ep %p not available, state %d\n", + shortname, epdata, epdata->state); + // FALLTHROUGH + case STATE_EP_UNBOUND: /* clean disconnect */ + val = -ENODEV; +fail: + up (&epdata->lock); + } + return val; +} + +static ssize_t +ep_io (struct ep_data *epdata, void *buf, unsigned len) +{ + DECLARE_COMPLETION (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; +} + + +/* handle a synchronous OUT bulk/intr/iso transfer */ +static ssize_t +ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr) +{ + struct ep_data *data = fd->private_data; + void *kbuf; + ssize_t value; + + if ((value = get_ready_ep (fd->f_flags, data)) < 0) + return value; + + /* halt any endpoint by doing a "wrong direction" i/o call */ + if (data->desc.bEndpointAddress & USB_DIR_IN) { + if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) + == USB_ENDPOINT_XFER_ISOC) + return -EINVAL; + DBG (data->dev, "%s halt\n", data->name); + spin_lock_irq (&data->dev->lock); + if (likely (data->ep != NULL)) + usb_ep_set_halt (data->ep); + spin_unlock_irq (&data->dev->lock); + up (&data->lock); + return -EBADMSG; + } + + /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */ + + value = -ENOMEM; + kbuf = kmalloc (len, SLAB_KERNEL); + if (unlikely (!kbuf)) + goto free1; + + value = ep_io (data, kbuf, len); + VDEBUG (data->dev, "%s read %d OUT, status %d\n", + data->name, len, value); + if (value >= 0 && copy_to_user (buf, kbuf, value)) + value = -EFAULT; + +free1: + up (&data->lock); + kfree (kbuf); + return value; +} + +/* handle a synchronous IN bulk/intr/iso transfer */ +static ssize_t +ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) +{ + struct ep_data *data = fd->private_data; + void *kbuf; + ssize_t value; + + if ((value = get_ready_ep (fd->f_flags, data)) < 0) + return value; + + /* halt any endpoint by doing a "wrong direction" i/o call */ + if (!(data->desc.bEndpointAddress & USB_DIR_IN)) { + if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) + == USB_ENDPOINT_XFER_ISOC) + return -EINVAL; + DBG (data->dev, "%s halt\n", data->name); + spin_lock_irq (&data->dev->lock); + if (likely (data->ep != NULL)) + usb_ep_set_halt (data->ep); + spin_unlock_irq (&data->dev->lock); + up (&data->lock); + return -EBADMSG; + } + + /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */ + + value = -ENOMEM; + kbuf = kmalloc (len, SLAB_KERNEL); + if (!kbuf) + goto free1; + if (copy_from_user (kbuf, buf, len)) { + value = -EFAULT; + goto free1; + } + + value = ep_io (data, kbuf, len); + VDEBUG (data->dev, "%s write %d IN, status %d\n", + data->name, len, value); +free1: + up (&data->lock); + kfree (kbuf); + return value; +} + +static int +ep_release (struct inode *inode, struct file *fd) +{ + struct ep_data *data = fd->private_data; + + /* 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; + } + put_ep (data); + return 0; +} + +static int ep_ioctl (struct inode *inode, 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)) < 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); + up (&data->lock); + return status; +} + +/*----------------------------------------------------------------------*/ + +/* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */ + +struct kiocb_priv { + struct usb_request *req; + struct ep_data *epdata; + void *buf; + char __user *ubuf; + unsigned actual; +}; + +static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e) +{ + struct kiocb_priv *priv = iocb->private; + struct ep_data *epdata; + int value; + + local_irq_disable(); + epdata = priv->epdata; + // spin_lock(&epdata->dev->lock); + kiocbSetCancelled(iocb); + 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(); + + aio_put_req(iocb); + return value; +} + +static ssize_t ep_aio_read_retry(struct kiocb *iocb) +{ + struct kiocb_priv *priv = iocb->private; + ssize_t status = priv->actual; + + /* we "retry" to get the right mm context for this: */ + status = copy_to_user(priv->ubuf, priv->buf, priv->actual); + if (unlikely(0 != status)) + status = -EFAULT; + else + status = priv->actual; + kfree(priv->buf); + kfree(priv); + aio_put_req(iocb); + return status; +} + +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 (NULL == iocb->ki_retry + || unlikely(0 == req->actual) + || unlikely(kiocbIsCancelled(iocb))) { + kfree(req->buf); + kfree(priv); + iocb->private = NULL; + /* aio_complete() reports bytes-transferred _and_ faults */ + if (unlikely(kiocbIsCancelled(iocb))) + aio_put_req(iocb); + else + aio_complete(iocb, + req->actual ? req->actual : req->status, + req->status); + } else { + /* retry() won't report both; so 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; + kick_iocb(iocb); + } + spin_unlock(&epdata->dev->lock); + + usb_ep_free_request(ep, req); + put_ep(epdata); +} + +static ssize_t +ep_aio_rwtail( + struct kiocb *iocb, + char *buf, + size_t len, + struct ep_data *epdata, + char __user *ubuf +) +{ + struct kiocb_priv *priv = (void *) &iocb->private; + struct usb_request *req; + ssize_t value; + + priv = kmalloc(sizeof *priv, GFP_KERNEL); + if (!priv) { + value = -ENOMEM; +fail: + kfree(buf); + return value; + } + iocb->private = priv; + priv->ubuf = ubuf; + + value = get_ready_ep(iocb->ki_filp->f_flags, epdata); + if (unlikely(value < 0)) { + kfree(priv); + goto fail; + } + + iocb->ki_cancel = ep_aio_cancel; + get_ep(epdata); + priv->epdata = epdata; + priv->actual = 0; + + /* 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); + if (likely(epdata->ep)) { + req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC); + if (likely(req)) { + 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); + } else + value = -EAGAIN; + } else + value = -ENODEV; + spin_unlock_irq(&epdata->dev->lock); + + up(&epdata->lock); + + if (unlikely(value)) { + kfree(priv); + put_ep(epdata); + } else + value = -EIOCBQUEUED; + return value; +} + +static ssize_t +ep_aio_read(struct kiocb *iocb, char __user *ubuf, size_t len, loff_t o) +{ + struct ep_data *epdata = iocb->ki_filp->private_data; + char *buf; + + if (unlikely(epdata->desc.bEndpointAddress & USB_DIR_IN)) + return -EINVAL; + buf = kmalloc(len, GFP_KERNEL); + if (unlikely(!buf)) + return -ENOMEM; + iocb->ki_retry = ep_aio_read_retry; + return ep_aio_rwtail(iocb, buf, len, epdata, ubuf); +} + +static ssize_t +ep_aio_write(struct kiocb *iocb, const char __user *ubuf, size_t len, loff_t o) +{ + struct ep_data *epdata = iocb->ki_filp->private_data; + char *buf; + + if (unlikely(!(epdata->desc.bEndpointAddress & USB_DIR_IN))) + return -EINVAL; + buf = kmalloc(len, GFP_KERNEL); + if (unlikely(!buf)) + return -ENOMEM; + if (unlikely(copy_from_user(buf, ubuf, len) != 0)) { + kfree(buf); + return -EFAULT; + } + return ep_aio_rwtail(iocb, buf, len, epdata, NULL); +} + +/*----------------------------------------------------------------------*/ + +/* used after endpoint configuration */ +static struct file_operations ep_io_operations = { + .owner = THIS_MODULE, + .llseek = no_llseek, + + .read = ep_read, + .write = ep_write, + .ioctl = ep_ioctl, + .release = ep_release, + + .aio_read = ep_aio_read, + .aio_write = ep_aio_write, +}; + +/* 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 file *fd, const char __user *buf, size_t len, loff_t *ptr) +{ + struct ep_data *data = fd->private_data; + struct usb_ep *ep; + u32 tag; + int value; + + if ((value = down_interruptible (&data->lock)) < 0) + return value; + + 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 */ + if (copy_from_user (&tag, buf, 4)) { + goto fail1; + } + 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 */ + if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) { + goto fail1; + } + 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; + if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE, + USB_DT_ENDPOINT_SIZE)) { + goto fail1; + } + 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; + } + } + value = len; + + spin_lock_irq (&data->dev->lock); + if (data->dev->state == STATE_DEV_UNBOUND) { + value = -ENOENT; + goto gone; + } else if ((ep = data->ep) == NULL) { + value = -ENODEV; + goto gone; + } + switch (data->dev->gadget->speed) { + case USB_SPEED_LOW: + case USB_SPEED_FULL: + value = usb_ep_enable (ep, &data->desc); + if (value == 0) + data->state = STATE_EP_ENABLED; + break; +#ifdef HIGHSPEED + case USB_SPEED_HIGH: + /* fails if caller didn't provide that descriptor... */ + value = usb_ep_enable (ep, &data->hs_desc); + if (value == 0) + data->state = STATE_EP_ENABLED; + break; +#endif + default: + DBG (data->dev, "unconnected, %s init deferred\n", + data->name); + data->state = STATE_EP_DEFER_ENABLE; + } + if (value == 0) + fd->f_op = &ep_io_operations; +gone: + spin_unlock_irq (&data->dev->lock); + if (value < 0) { +fail: + data->desc.bDescriptorType = 0; + data->hs_desc.bDescriptorType = 0; + } + up (&data->lock); + return value; +fail0: + value = -EINVAL; + goto fail; +fail1: + value = -EFAULT; + goto fail; +} + +static int +ep_open (struct inode *inode, struct file *fd) +{ + struct ep_data *data = inode->u.generic_ip; + int value = -EBUSY; + + if (down_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); + up (&data->lock); + return value; +} + +/* used before endpoint configuration */ +static struct file_operations ep_config_operations = { + .owner = THIS_MODULE, + .llseek = no_llseek, + + .open = ep_open, + .write = ep_config, + .release = ep_release, +}; + +/*----------------------------------------------------------------------*/ + +/* 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) { + usb_ep_free_buffer (ep, req->buf, req->dma, req->length); + req->buf = dev->rbuf; + req->dma = DMA_ADDR_INVALID; + } + 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; + int free = 1; + + /* for control OUT, data must still get to userspace */ + 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); + } else if (dev->state == STATE_SETUP) + dev->state = STATE_CONNECTED; + + /* clean up as appropriate */ + if (free && req->buf != &dev->rbuf) + clean_req (ep, req); + req->complete = epio_complete; +} + +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 = usb_ep_alloc_buffer (ep, len, &req->dma, GFP_ATOMIC); + if (req->buf == 0) { + req->buf = dev->rbuf; + return -ENOMEM; + } + req->complete = ep0_complete; + req->length = len; + 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); + + /* 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_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_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_CONNECTED; + + /* assume that was SET_CONFIGURATION */ + if (dev->current_config) { + unsigned power; +#ifdef HIGHSPEED + if (dev->gadget->speed == USB_SPEED_HIGH) + power = dev->hs_config->bMaxPower; + else +#endif + 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->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; + 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; + int tmp = dev->ev_next; + + len = min (len, tmp * sizeof (struct usb_gadgetfs_event)); + n = len / sizeof (struct usb_gadgetfs_event); + + /* ep0 can't deliver events when STATE_SETUP */ + for (i = 0; i < n; i++) { + if (dev->event [i].type == GADGETFS_SETUP) { + len = n = i + 1; + len *= sizeof (struct usb_gadgetfs_event); + n = 0; + break; + } + } + spin_unlock_irq (&dev->lock); + if (copy_to_user (buf, &dev->event, len)) + retval = -EFAULT; + else + retval = len; + if (len > 0) { + len /= sizeof (struct usb_gadgetfs_event); + + /* NOTE this doesn't guard against broken drivers; + * concurrent ep0 readers may lose events. + */ + spin_lock_irq (&dev->lock); + dev->ev_next -= len; + if (dev->ev_next != 0) + memmove (&dev->event, &dev->event [len], + sizeof (struct usb_gadgetfs_event) + * (tmp - len)); + if (n == 0) + dev->state = STATE_SETUP; + 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", __FUNCTION__, state); + retval = -ESRCH; + break; + case STATE_UNCONNECTED: + case STATE_CONNECTED: + spin_unlock_irq (&dev->lock); + DBG (dev, "%s wait\n", __FUNCTION__); + + /* 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_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\n", 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 (); + } + event = &dev->event [dev->ev_next++]; + BUG_ON (dev->ev_next > N_EVENT); + VDEBUG (dev, "ev %d, next %d\n", type, dev->ev_next); + 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; + + spin_lock_irq (&dev->lock); + + /* 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_SETUP) { + + /* IN DATA+STATUS caller makes len <= wLength */ + if (dev->setup_in) { + retval = setup_req (dev->gadget->ep0, dev->req, len); + if (retval == 0) { + spin_unlock_irq (&dev->lock); + if (copy_from_user (dev->req->buf, buf, len)) + retval = -EFAULT; + else + retval = usb_ep_queue ( + dev->gadget->ep0, dev->req, + GFP_KERNEL); + if (retval < 0) { + spin_lock_irq (&dev->lock); + clean_req (dev->gadget->ep0, dev->req); + spin_unlock_irq (&dev->lock); + } 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_CONNECTED; + } else { + DBG(dev, "bogus ep0out stall!\n"); + } + } else + DBG (dev, "fail %s, state %d\n", __FUNCTION__, dev->state); + + spin_unlock_irq (&dev->lock); + return retval; +} + +static int +ep0_fasync (int f, struct file *fd, int on) +{ + struct dev_data *dev = fd->private_data; + // |