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|
/*
* Gadget Function Driver for MTP
*
* Copyright (C) 2010 Google, Inc.
* Author: Mike Lockwood <lockwood@android.com>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* 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.
*
*/
/* #define DEBUG */
/* #define VERBOSE_DEBUG */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/delay.h>
#include <linux/wait.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/types.h>
#include <linux/file.h>
#include <linux/device.h>
#include <linux/miscdevice.h>
#include <linux/usb.h>
#include <linux/usb_usual.h>
#include <linux/usb/ch9.h>
#include <linux/usb/f_mtp.h>
#define MTP_BULK_BUFFER_SIZE 16384
#define INTR_BUFFER_SIZE 28
/* String IDs */
#define INTERFACE_STRING_INDEX 0
/* values for mtp_dev.state */
#define STATE_OFFLINE 0 /* initial state, disconnected */
#define STATE_READY 1 /* ready for userspace calls */
#define STATE_BUSY 2 /* processing userspace calls */
#define STATE_CANCELED 3 /* transaction canceled by host */
#define STATE_ERROR 4 /* error from completion routine */
/* number of tx and rx requests to allocate */
#define TX_REQ_MAX 4
#define RX_REQ_MAX 2
#define INTR_REQ_MAX 5
/* ID for Microsoft MTP OS String */
#define MTP_OS_STRING_ID 0xEE
/* MTP class reqeusts */
#define MTP_REQ_CANCEL 0x64
#define MTP_REQ_GET_EXT_EVENT_DATA 0x65
#define MTP_REQ_RESET 0x66
#define MTP_REQ_GET_DEVICE_STATUS 0x67
/* constants for device status */
#define MTP_RESPONSE_OK 0x2001
#define MTP_RESPONSE_DEVICE_BUSY 0x2019
static const char mtp_shortname[] = "mtp_usb";
struct mtp_dev {
struct usb_function function;
struct usb_composite_dev *cdev;
spinlock_t lock;
struct usb_ep *ep_in;
struct usb_ep *ep_out;
struct usb_ep *ep_intr;
int state;
/* synchronize access to our device file */
atomic_t open_excl;
/* to enforce only one ioctl at a time */
atomic_t ioctl_excl;
struct list_head tx_idle;
struct list_head intr_idle;
wait_queue_head_t read_wq;
wait_queue_head_t write_wq;
wait_queue_head_t intr_wq;
struct usb_request *rx_req[RX_REQ_MAX];
int rx_done;
/* for processing MTP_SEND_FILE, MTP_RECEIVE_FILE and
* MTP_SEND_FILE_WITH_HEADER ioctls on a work queue
*/
struct workqueue_struct *wq;
struct work_struct send_file_work;
struct work_struct receive_file_work;
struct file *xfer_file;
loff_t xfer_file_offset;
int64_t xfer_file_length;
unsigned xfer_send_header;
uint16_t xfer_command;
uint32_t xfer_transaction_id;
int xfer_result;
};
static struct usb_interface_descriptor mtp_interface_desc = {
.bLength = USB_DT_INTERFACE_SIZE,
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = 0,
.bNumEndpoints = 3,
.bInterfaceClass = USB_CLASS_VENDOR_SPEC,
.bInterfaceSubClass = USB_SUBCLASS_VENDOR_SPEC,
.bInterfaceProtocol = 0,
};
static struct usb_interface_descriptor ptp_interface_desc = {
.bLength = USB_DT_INTERFACE_SIZE,
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = 0,
.bNumEndpoints = 3,
.bInterfaceClass = USB_CLASS_STILL_IMAGE,
.bInterfaceSubClass = 1,
.bInterfaceProtocol = 1,
};
static struct usb_endpoint_descriptor mtp_highspeed_in_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = __constant_cpu_to_le16(512),
};
static struct usb_endpoint_descriptor mtp_highspeed_out_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = __constant_cpu_to_le16(512),
};
static struct usb_endpoint_descriptor mtp_fullspeed_in_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
};
static struct usb_endpoint_descriptor mtp_fullspeed_out_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
};
static struct usb_endpoint_descriptor mtp_intr_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = __constant_cpu_to_le16(INTR_BUFFER_SIZE),
.bInterval = 6,
};
static struct usb_descriptor_header *fs_mtp_descs[] = {
(struct usb_descriptor_header *) &mtp_interface_desc,
(struct usb_descriptor_header *) &mtp_fullspeed_in_desc,
(struct usb_descriptor_header *) &mtp_fullspeed_out_desc,
(struct usb_descriptor_header *) &mtp_intr_desc,
NULL,
};
static struct usb_descriptor_header *hs_mtp_descs[] = {
(struct usb_descriptor_header *) &mtp_interface_desc,
(struct usb_descriptor_header *) &mtp_highspeed_in_desc,
(struct usb_descriptor_header *) &mtp_highspeed_out_desc,
(struct usb_descriptor_header *) &mtp_intr_desc,
NULL,
};
static struct usb_descriptor_header *fs_ptp_descs[] = {
(struct usb_descriptor_header *) &ptp_interface_desc,
(struct usb_descriptor_header *) &mtp_fullspeed_in_desc,
(struct usb_descriptor_header *) &mtp_fullspeed_out_desc,
(struct usb_descriptor_header *) &mtp_intr_desc,
NULL,
};
static struct usb_descriptor_header *hs_ptp_descs[] = {
(struct usb_descriptor_header *) &ptp_interface_desc,
(struct usb_descriptor_header *) &mtp_highspeed_in_desc,
(struct usb_descriptor_header *) &mtp_highspeed_out_desc,
(struct usb_descriptor_header *) &mtp_intr_desc,
NULL,
};
static struct usb_string mtp_string_defs[] = {
/* Naming interface "MTP" so libmtp will recognize us */
[INTERFACE_STRING_INDEX].s = "MTP",
{ }, /* end of list */
};
static struct usb_gadget_strings mtp_string_table = {
.language = 0x0409, /* en-US */
.strings = mtp_string_defs,
};
static struct usb_gadget_strings *mtp_strings[] = {
&mtp_string_table,
NULL,
};
/* Microsoft MTP OS String */
static u8 mtp_os_string[] = {
18, /* sizeof(mtp_os_string) */
USB_DT_STRING,
/* Signature field: "MSFT100" */
'M', 0, 'S', 0, 'F', 0, 'T', 0, '1', 0, '0', 0, '0', 0,
/* vendor code */
1,
/* padding */
0
};
/* Microsoft Extended Configuration Descriptor Header Section */
struct mtp_ext_config_desc_header {
__le32 dwLength;
__u16 bcdVersion;
__le16 wIndex;
__u8 bCount;
__u8 reserved[7];
};
/* Microsoft Extended Configuration Descriptor Function Section */
struct mtp_ext_config_desc_function {
__u8 bFirstInterfaceNumber;
__u8 bInterfaceCount;
__u8 compatibleID[8];
__u8 subCompatibleID[8];
__u8 reserved[6];
};
/* MTP Extended Configuration Descriptor */
struct {
struct mtp_ext_config_desc_header header;
struct mtp_ext_config_desc_function function;
} mtp_ext_config_desc = {
.header = {
.dwLength = __constant_cpu_to_le32(sizeof(mtp_ext_config_desc)),
.bcdVersion = __constant_cpu_to_le16(0x0100),
.wIndex = __constant_cpu_to_le16(4),
.bCount = __constant_cpu_to_le16(1),
},
.function = {
.bFirstInterfaceNumber = 0,
.bInterfaceCount = 1,
.compatibleID = { 'M', 'T', 'P' },
},
};
struct mtp_device_status {
__le16 wLength;
__le16 wCode;
};
/* temporary variable used between mtp_open() and mtp_gadget_bind() */
static struct mtp_dev *_mtp_dev;
static inline struct mtp_dev *func_to_mtp(struct usb_function *f)
{
return container_of(f, struct mtp_dev, function);
}
static struct usb_request *mtp_request_new(struct usb_ep *ep, int buffer_size)
{
struct usb_request *req = usb_ep_alloc_request(ep, GFP_KERNEL);
if (!req)
return NULL;
/* now allocate buffers for the requests */
req->buf = kmalloc(buffer_size, GFP_KERNEL);
if (!req->buf) {
usb_ep_free_request(ep, req);
return NULL;
}
return req;
}
static void mtp_request_free(struct usb_request *req, struct usb_ep *ep)
{
if (req) {
kfree(req->buf);
usb_ep_free_request(ep, req);
}
}
static inline int mtp_lock(atomic_t *excl)
{
if (atomic_inc_return(excl) == 1) {
return 0;
} else {
atomic_dec(excl);
return -1;
}
}
static inline void mtp_unlock(atomic_t *excl)
{
atomic_dec(excl);
}
/* add a request to the tail of a list */
static void mtp_req_put(struct mtp_dev *dev, struct list_head *head,
struct usb_request *req)
{
unsigned long flags;
spin_lock_irqsave(&dev->lock, flags);
list_add_tail(&req->list, head);
spin_unlock_irqrestore(&dev->lock, flags);
}
/* remove a request from the head of a list */
static struct usb_request
*mtp_req_get(struct mtp_dev *dev, struct list_head *head)
{
unsigned long flags;
struct usb_request *req;
spin_lock_irqsave(&dev->lock, flags);
if (list_empty(head)) {
req = 0;
} else {
req = list_first_entry(head, struct usb_request, list);
list_del(&req->list);
}
spin_unlock_irqrestore(&dev->lock, flags);
return req;
}
static void mtp_complete_in(struct usb_ep *ep, struct usb_request *req)
{
struct mtp_dev *dev = _mtp_dev;
if (req->status != 0)
dev->state = STATE_ERROR;
mtp_req_put(dev, &dev->tx_idle, req);
wake_up(&dev->write_wq);
}
static void mtp_complete_out(struct usb_ep *ep, struct usb_request *req)
{
struct mtp_dev *dev = _mtp_dev;
dev->rx_done = 1;
if (req->status != 0)
dev->state = STATE_ERROR;
wake_up(&dev->read_wq);
}
static void mtp_complete_intr(struct usb_ep *ep, struct usb_request *req)
{
struct mtp_dev *dev = _mtp_dev;
if (req->status != 0)
dev->state = STATE_ERROR;
mtp_req_put(dev, &dev->intr_idle, req);
wake_up(&dev->intr_wq);
}
static int mtp_create_bulk_endpoints(struct mtp_dev *dev,
struct usb_endpoint_descriptor *in_desc,
struct usb_endpoint_descriptor *out_desc,
struct usb_endpoint_descriptor *intr_desc)
{
struct usb_composite_dev *cdev = dev->cdev;
struct usb_request *req;
struct usb_ep *ep;
int i;
DBG(cdev, "create_bulk_endpoints dev: %p\n", dev);
ep = usb_ep_autoconfig(cdev->gadget, in_desc);
if (!ep) {
DBG(cdev, "usb_ep_autoconfig for ep_in failed\n");
return -ENODEV;
}
DBG(cdev, "usb_ep_autoconfig for ep_in got %s\n", ep->name);
ep->driver_data = dev; /* claim the endpoint */
dev->ep_in = ep;
ep = usb_ep_autoconfig(cdev->gadget, out_desc);
if (!ep) {
DBG(cdev, "usb_ep_autoconfig for ep_out failed\n");
return -ENODEV;
}
DBG(cdev, "usb_ep_autoconfig for mtp ep_out got %s\n", ep->name);
ep->driver_data = dev; /* claim the endpoint */
dev->ep_out = ep;
ep = usb_ep_autoconfig(cdev->gadget, out_desc);
if (!ep) {
DBG(cdev, "usb_ep_autoconfig for ep_out failed\n");
return -ENODEV;
}
DBG(cdev, "usb_ep_autoconfig for mtp ep_out got %s\n", ep->name);
ep->driver_data = dev; /* claim the endpoint */
dev->ep_out = ep;
ep = usb_ep_autoconfig(cdev->gadget, intr_desc);
if (!ep) {
DBG(cdev, "usb_ep_autoconfig for ep_intr failed\n");
return -ENODEV;
}
DBG(cdev, "usb_ep_autoconfig for mtp ep_intr got %s\n", ep->name);
ep->driver_data = dev; /* claim the endpoint */
dev->ep_intr = ep;
/* now allocate requests for our endpoints */
for (i = 0; i < TX_REQ_MAX; i++) {
req = mtp_request_new(dev->ep_in, MTP_BULK_BUFFER_SIZE);
if (!req)
goto fail;
req->complete = mtp_complete_in;
mtp_req_put(dev, &dev->tx_idle, req);
}
for (i = 0; i < RX_REQ_MAX; i++) {
req = mtp_request_new(dev->ep_out, MTP_BULK_BUFFER_SIZE);
if (!req)
goto fail;
req->complete = mtp_complete_out;
dev->rx_req[i] = req;
}
for (i = 0; i < INTR_REQ_MAX; i++) {
req = mtp_request_new(dev->ep_intr, INTR_BUFFER_SIZE);
if (!req)
goto fail;
req->complete = mtp_complete_intr;
mtp_req_put(dev, &dev->intr_idle, req);
}
return 0;
fail:
printk(KERN_ERR "mtp_bind() could not allocate requests\n");
return -1;
}
static ssize_t mtp_read(struct file *fp, char __user *buf,
size_t count, loff_t *pos)
{
struct mtp_dev *dev = fp->private_data;
struct usb_composite_dev *cdev = dev->cdev;
struct usb_request *req;
int r = count, xfer;
int ret = 0;
DBG(cdev, "mtp_read(%d)\n", count);
if (count > MTP_BULK_BUFFER_SIZE)
return -EINVAL;
/* we will block until we're online */
DBG(cdev, "mtp_read: waiting for online state\n");
ret = wait_event_interruptible(dev->read_wq,
dev->state != STATE_OFFLINE);
if (ret < 0) {
r = ret;
goto done;
}
spin_lock_irq(&dev->lock);
if (dev->state == STATE_CANCELED) {
/* report cancelation to userspace */
dev->state = STATE_READY;
spin_unlock_irq(&dev->lock);
return -ECANCELED;
}
dev->state = STATE_BUSY;
spin_unlock_irq(&dev->lock);
requeue_req:
/* queue a request */
req = dev->rx_req[0];
req->length = count;
dev->rx_done = 0;
ret = usb_ep_queue(dev->ep_out, req, GFP_KERNEL);
if (ret < 0) {
r = -EIO;
goto done;
} else {
DBG(cdev, "rx %p queue\n", req);
}
/* wait for a request to complete */
ret = wait_event_interruptible(dev->read_wq, dev->rx_done);
if (ret < 0) {
r = ret;
usb_ep_dequeue(dev->ep_out, req);
goto done;
}
if (dev->state == STATE_BUSY) {
/* If we got a 0-len packet, throw it back and try again. */
if (req->actual == 0)
goto requeue_req;
DBG(cdev, "rx %p %d\n", req, req->actual);
xfer = (req->actual < count) ? req->actual : count;
r = xfer;
if (copy_to_user(buf, req->buf, xfer))
r = -EFAULT;
} else
r = -EIO;
done:
spin_lock_irq(&dev->lock);
if (dev->state == STATE_CANCELED)
r = -ECANCELED;
else if (dev->state != STATE_OFFLINE)
dev->state = STATE_READY;
spin_unlock_irq(&dev->lock);
DBG(cdev, "mtp_read returning %d\n", r);
return r;
}
static ssize_t mtp_write(struct file *fp, const char __user *buf,
size_t count, loff_t *pos)
{
struct mtp_dev *dev = fp->private_data;
struct usb_composite_dev *cdev = dev->cdev;
struct usb_request *req = 0;
int r = count, xfer;
int sendZLP = 0;
int ret;
DBG(cdev, "mtp_write(%d)\n", count);
spin_lock_irq(&dev->lock);
if (dev->state == STATE_CANCELED) {
/* report cancelation to userspace */
dev->state = STATE_READY;
spin_unlock_irq(&dev->lock);
return -ECANCELED;
}
if (dev->state == STATE_OFFLINE) {
spin_unlock_irq(&dev->lock);
return -ENODEV;
}
dev->state = STATE_BUSY;
spin_unlock_irq(&dev->lock);
/* we need to send a zero length packet to signal the end of transfer
* if the transfer size is aligned to a packet boundary.
*/
if ((count & (dev->ep_in->maxpacket - 1)) == 0)
sendZLP = 1;
while (count > 0 || sendZLP) {
/* so we exit after sending ZLP */
if (count == 0)
sendZLP = 0;
if (dev->state != STATE_BUSY) {
DBG(cdev, "mtp_write dev->error\n");
r = -EIO;
break;
}
/* get an idle tx request to use */
req = 0;
ret = wait_event_interruptible(dev->write_wq,
((req = mtp_req_get(dev, &dev->tx_idle))
|| dev->state != STATE_BUSY));
if (!req) {
r = ret;
break;
}
if (count > MTP_BULK_BUFFER_SIZE)
xfer = MTP_BULK_BUFFER_SIZE;
else
xfer = count;
if (xfer && copy_from_user(req->buf, buf, xfer)) {
r = -EFAULT;
break;
}
req->length = xfer;
ret = usb_ep_queue(dev->ep_in, req, GFP_KERNEL);
if (ret < 0) {
DBG(cdev, "mtp_write: xfer error %d\n", ret);
r = -EIO;
break;
}
buf += xfer;
count -= xfer;
/* zero this so we don't try to free it on error exit */
req = 0;
}
if (req)
mtp_req_put(dev, &dev->tx_idle, req);
spin_lock_irq(&dev->lock);
if (dev->state == STATE_CANCELED)
r = -ECANCELED;
else if (dev->state != STATE_OFFLINE)
dev->state = STATE_READY;
spin_unlock_irq(&dev->lock);
DBG(cdev, "mtp_write returning %d\n", r);
return r;
}
/* read from a local file and write to USB */
static void send_file_work(struct work_struct *data)
{
struct mtp_dev *dev = container_of(data, struct mtp_dev,
send_file_work);
struct usb_composite_dev *cdev = dev->cdev;
struct usb_request *req = 0;
struct mtp_data_header *header;
struct file *filp;
loff_t offset;
int64_t count;
int xfer, ret, hdr_size;
int r = 0;
int sendZLP = 0;
/* read our parameters */
smp_rmb();
filp = dev->xfer_file;
offset = dev->xfer_file_offset;
count = dev->xfer_file_length;
DBG(cdev, "send_file_work(%lld %lld)\n", offset, count);
if (dev->xfer_send_header) {
hdr_size = sizeof(struct mtp_data_header);
count += hdr_size;
} else {
hdr_size = 0;
}
/* we need to send a zero length packet to signal the end of transfer
* if the transfer size is aligned to a packet boundary.
*/
if ((count & (dev->ep_in->maxpacket - 1)) == 0)
sendZLP = 1;
while (count > 0 || sendZLP) {
/* so we exit after sending ZLP */
if (count == 0)
sendZLP = 0;
/* get an idle tx request to use */
req = 0;
ret = wait_event_interruptible(dev->write_wq,
(req = mtp_req_get(dev, &dev->tx_idle))
|| dev->state != STATE_BUSY);
if (dev->state == STATE_CANCELED) {
r = -ECANCELED;
break;
}
if (!req) {
r = ret;
break;
}
if (count > MTP_BULK_BUFFER_SIZE)
xfer = MTP_BULK_BUFFER_SIZE;
else
xfer = count;
if (hdr_size) {
/* prepend MTP data header */
header = (struct mtp_data_header *)req->buf;
header->length = __cpu_to_le32(count);
header->type = __cpu_to_le16(2); /* data packet */
header->command = __cpu_to_le16(dev->xfer_command);
header->transaction_id =
__cpu_to_le32(dev->xfer_transaction_id);
}
ret = vfs_read(filp, req->buf + hdr_size, xfer - hdr_size,
&offset);
if (ret < 0) {
r = ret;
break;
}
xfer = ret + hdr_size;
hdr_size = 0;
req->length = xfer;
ret = usb_ep_queue(dev->ep_in, req, GFP_KERNEL);
if (ret < 0) {
DBG(cdev, "send_file_work: xfer error %d\n", ret);
dev->state = STATE_ERROR;
r = -EIO;
break;
}
count -= xfer;
/* zero this so we don't try to free it on error exit */
req = 0;
}
if (req)
mtp_req_put(dev, &dev->tx_idle, req);
DBG(cdev, "send_file_work returning %d\n", r);
/* write the result */
dev->xfer_result = r;
smp_wmb();
}
/* read from USB and write to a local file */
static void receive_file_work(struct work_struct *data)
{
struct mtp_dev *dev = container_of(data, struct mtp_dev,
receive_file_work);
struct usb_composite_dev *cdev = dev->cdev;
struct usb_request *read_req = NULL, *write_req = NULL;
struct file *filp;
loff_t offset;
int64_t count;
int ret, cur_buf = 0;
int r = 0;
/* read our parameters */
smp_rmb();
filp = dev->xfer_file;
offset = dev->xfer_file_offset;
count = dev->xfer_file_length;
DBG(cdev, "receive_file_work(%lld)\n", count);
while (count > 0 || write_req) {
if (count > 0) {
/* queue a request */
read_req = dev->rx_req[cur_buf];
cur_buf = (cur_buf + 1) % RX_REQ_MAX;
read_req->length = (count > MTP_BULK_BUFFER_SIZE
? MTP_BULK_BUFFER_SIZE : count);
dev->rx_done = 0;
ret = usb_ep_queue(dev->ep_out, read_req, GFP_KERNEL);
if (ret < 0) {
r = -EIO;
dev->state = STATE_ERROR;
break;
}
}
if (write_req) {
DBG(cdev, "rx %p %d\n", write_req, write_req->actual);
ret = vfs_write(filp, write_req->buf, write_req->actual,
&offset);
DBG(cdev, "vfs_write %d\n", ret);
if (ret != write_req->actual) {
r = -EIO;
dev->state = STATE_ERROR;
break;
}
write_req = NULL;
}
if (read_req) {
/* wait for our last read to complete */
ret = wait_event_interruptible(dev->read_wq,
dev->rx_done || dev->state != STATE_BUSY);
if (dev->state == STATE_CANCELED) {
r = -ECANCELED;
if (!dev->rx_done)
usb_ep_dequeue(dev->ep_out, read_req);
break;
}
/* if xfer_file_length is 0xFFFFFFFF, then we read until
* we get a zero length packet
*/
if (count != 0xFFFFFFFF)
count -= read_req->actual;
if (read_req->actual < read_req->length) {
/*
* short packet is used to signal EOF for
* sizes > 4 gig
*/
DBG(cdev, "got short packet\n");
count = 0;
}
write_req = read_req;
read_req = NULL;
}
}
DBG(cdev, "receive_file_work returning %d\n", r);
/* write the result */
dev->xfer_result = r;
smp_wmb();
}
static int mtp_send_event(struct mtp_dev *dev, struct mtp_event *event)
{
struct usb_request *req = NULL;
int ret;
int length = event->length;
DBG(dev->cdev, "mtp_send_event(%d)\n", event->length);
if (length < 0 || length > INTR_BUFFER_SIZE)
return -EINVAL;
if (dev->state == STATE_OFFLINE)
return -ENODEV;
ret = wait_event_interruptible_timeout(dev->intr_wq,
(req = mtp_req_get(dev, &dev->intr_idle)),
msecs_to_jiffies(1000));
if (!req)
return -ETIME;
if (copy_from_user(req->buf, (void __user *)event->data, length)) {
mtp_req_put(dev, &dev->intr_idle, req);
return -EFAULT;
}
req->length = length;
ret = usb_ep_queue(dev->ep_intr, req, GFP_KERNEL);
if (ret)
mtp_req_put(dev, &dev->intr_idle, req);
return ret;
}
static long mtp_ioctl(struct file *fp, unsigned code, unsigned long value)
{
struct mtp_dev *dev = fp->private_data;
struct file *filp = NULL;
int ret = -EINVAL;
if (mtp_lock(&dev->ioctl_excl))
return -EBUSY;
switch (code) {
case MTP_SEND_FILE:
case MTP_RECEIVE_FILE:
case MTP_SEND_FILE_WITH_HEADER:
{
struct mtp_file_range mfr;
struct work_struct *work;
spin_lock_irq(&dev->lock);
if (dev->state == STATE_CANCELED) {
/* report cancelation to userspace */
dev->state = STATE_READY;
spin_unlock_irq(&dev->lock);
ret = -ECANCELED;
goto out;
}
if (dev->state == STATE_OFFLINE) {
spin_unlock_irq(&dev->lock);
ret = -ENODEV;
goto out;
}
dev->state = STATE_BUSY;
spin_unlock_irq(&dev->lock);
if (copy_from_user(&mfr, (void __user *)value, sizeof(mfr))) {
ret = -EFAULT;
goto fail;
}
/* hold a reference to the file while we are working with it */
filp = fget(mfr.fd);
if (!filp) {
ret = -EBADF;
goto fail;
}
/* write the parameters */
dev->xfer_file = filp;
dev->xfer_file_offset = mfr.offset;
dev->xfer_file_length = mfr.length;
smp_wmb();
if (code == MTP_SEND_FILE_WITH_HEADER) {
work = &dev->send_file_work;
dev->xfer_send_header = 1;
dev->xfer_command = mfr.command;
dev->xfer_transaction_id = mfr.transaction_id;
} else if (code == MTP_SEND_FILE) {
work = &dev->send_file_work;
dev->xfer_send_header = 0;
} else {
work = &dev->receive_file_work;
}
/* We do the file transfer on a work queue so it will run
* in kernel context, which is necessary for vfs_read and
* vfs_write to use our buffers in the kernel address space.
*/
queue_work(dev->wq, work);
/* wait for operation to complete */
flush_workqueue(dev->wq);
fput(filp);
/* read the result */
smp_rmb();
ret = dev->xfer_result;
break;
}
case MTP_SEND_EVENT:
{
struct mtp_event event;
/* return here so we don't change dev->state below,
* which would interfere with bulk transfer state.
*/
if (copy_from_user(&event, (void __user *)value, sizeof(event)))
ret = -EFAULT;
else
ret = mtp_send_event(dev, &event);
goto out;
}
}
fail:
spin_lock_irq(&dev->lock);
if (dev->state == STATE_CANCELED)
ret = -ECANCELED;
else if (dev->state != STATE_OFFLINE)
dev->state = STATE_READY;
spin_unlock_irq(&dev->lock);
out:
mtp_unlock(&dev->ioctl_excl);
DBG(dev->cdev, "ioctl returning %d\n", ret);
return ret;
}
static int mtp_open(struct inode *ip, struct file *fp)
{
printk(KERN_INFO "mtp_open\n");
if (mtp_lock(&_mtp_dev->open_excl))
return -EBUSY;
/* clear any error condition */
if (_mtp_dev->state != STATE_OFFLINE)
_mtp_dev->state = STATE_READY;
fp->private_data = _mtp_dev;
return 0;
}
static int mtp_release(struct inode *ip, struct file *fp)
{
printk(KERN_INFO "mtp_release\n");
mtp_unlock(&_mtp_dev->open_excl);
return 0;
}
/* file operations for /dev/mtp_usb */
static const struct file_operations mtp_fops = {
.owner = THIS_MODULE,
.read = mtp_read,
.write = mtp_write,
.unlocked_ioctl = mtp_ioctl,
.open = mtp_open,
.release = mtp_release,
};
static struct miscdevice mtp_device = {
.minor = MISC_DYNAMIC_MINOR,
.name = mtp_shortname,
.fops = &mtp_fops,
};
static int mtp_ctrlrequest(struct usb_composite_dev *cdev,
const struct usb_ctrlrequest *ctrl)
{
struct mtp_dev *dev = _mtp_dev;
int value = -EOPNOTSUPP;
u16 w_index = le16_to_cpu(ctrl->wIndex);
u16 w_value = le16_to_cpu(ctrl->wValue);
u16 w_length = le16_to_cpu(ctrl->wLength);
unsigned long flags;
VDBG(cdev, "mtp_ctrlrequest "
"%02x.%02x v%04x i%04x l%u\n",
ctrl->bRequestType, ctrl->bRequest,
w_value, w_index, w_length);
/* Handle MTP OS string */
if (ctrl->bRequestType ==
(USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE)
&& ctrl->bRequest == USB_REQ_GET_DESCRIPTOR
&& (w_value >> 8) == USB_DT_STRING
&& (w_value & 0xFF) == MTP_OS_STRING_ID) {
value = (w_length < sizeof(mtp_os_string)
? w_length : sizeof(mtp_os_string));
memcpy(cdev->req->buf, mtp_os_string, value);
} else if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_VENDOR) {
/* Handle MTP OS descriptor */
DBG(cdev, "vendor request: %d index: %d value: %d length: %d\n",
ctrl->bRequest, w_index, w_value, w_length);
if (ctrl->bRequest == 1
&& (ctrl->bRequestType & USB_DIR_IN)
&& (w_index == 4 || w_index == 5)) {
value = (w_length < sizeof(mtp_ext_config_desc) ?
w_length : sizeof(mtp_ext_config_desc));
memcpy(cdev->req->buf, &mtp_ext_config_desc, value);
}
} else if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS) {
DBG(cdev, "class request: %d index: %d value: %d length: %d\n",
ctrl->bRequest, w_index, w_value, w_length);
if (ctrl->bRequest == MTP_REQ_CANCEL && w_index == 0
&& w_value == 0) {
DBG(cdev, "MTP_REQ_CANCEL\n");
spin_lock_irqsave(&dev->lock, flags);
if (dev->state == STATE_BUSY) {
dev->state = STATE_CANCELED;
wake_up(&dev->read_wq);
wake_up(&dev->write_wq);
}
spin_unlock_irqrestore(&dev->lock, flags);
/* We need to queue a request to read the remaining
* bytes, but we don't actually need to look at
* the contents.
*/
value = w_length;
} else if (ctrl->bRequest == MTP_REQ_GET_DEVICE_STATUS
&& w_index == 0 && w_value == 0) {
struct mtp_device_status *status = cdev->req->buf;
status->wLength =
__constant_cpu_to_le16(sizeof(*status));
DBG(cdev, "MTP_REQ_GET_DEVICE_STATUS\n");
spin_lock_irqsave(&dev->lock, flags);
/* device status is "busy" until we report
* the cancelation to userspace
*/
if (dev->state == STATE_CANCELED)
status->wCode =
__cpu_to_le16(MTP_RESPONSE_DEVICE_BUSY);
else
status->wCode =
__cpu_to_le16(MTP_RESPONSE_OK);
spin_unlock_irqrestore(&dev->lock, flags);
value = sizeof(*status);
}
}
/* respond with data transfer or status phase? */
if (value >= 0) {
int rc;
cdev->req->zero = value < w_length;
cdev->req->length = value;
rc = usb_ep_queue(cdev->gadget->ep0, cdev->req, GFP_ATOMIC);
if (rc < 0)
ERROR(cdev, "%s: response queue error\n", __func__);
}
return value;
}
static int
mtp_function_bind(struct usb_configuration *c, struct usb_function *f)
{
struct usb_composite_dev *cdev = c->cdev;
struct mtp_dev *dev = func_to_mtp(f);
int id;
int ret;
dev->cdev = cdev;
DBG(cdev, "mtp_function_bind dev: %p\n", dev);
/* allocate interface ID(s) */
id = usb_interface_id(c, f);
if (id < 0)
return id;
mtp_interface_desc.bInterfaceNumber = id;
/* allocate endpoints */
ret = mtp_create_bulk_endpoints(dev, &mtp_fullspeed_in_desc,
&mtp_fullspeed_out_desc, &mtp_intr_desc);
if (ret)
return ret;
/* support high speed hardware */
if (gadget_is_dualspeed(c->cdev->gadget)) {
mtp_highspeed_in_desc.bEndpointAddress =
mtp_fullspeed_in_desc.bEndpointAddress;
mtp_highspeed_out_desc.bEndpointAddress =
mtp_fullspeed_out_desc.bEndpointAddress;
}
DBG(cdev, "%s speed %s: IN/%s, OUT/%s\n",
gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
f->name, dev->ep_in->name, dev->ep_out->name);
return 0;
}
static void
mtp_function_unbind(struct usb_configuration *c, struct usb_function *f)
{
struct mtp_dev *dev = func_to_mtp(f);
struct usb_request *req;
int i;
while ((req = mtp_req_get(dev, &dev->tx_idle)))
mtp_request_free(req, dev->ep_in);
for (i = 0; i < RX_REQ_MAX; i++)
mtp_request_free(dev->rx_req[i], dev->ep_out);
while ((req = mtp_req_get(dev, &dev->intr_idle)))
mtp_request_free(req, dev->ep_intr);
dev->state = STATE_OFFLINE;
}
static int mtp_function_set_alt(struct usb_function *f,
unsigned intf, unsigned alt)
{
struct mtp_dev *dev = func_to_mtp(f);
struct usb_composite_dev *cdev = f->config->cdev;
int ret;
DBG(cdev, "mtp_function_set_alt intf: %d alt: %d\n", intf, alt);
ret = config_ep_by_speed(cdev->gadget, f, dev->ep_in);
if (ret)
return ret;
ret = usb_ep_enable(dev->ep_in);
if (ret)
return ret;
ret = config_ep_by_speed(cdev->gadget, f, dev->ep_out);
if (ret)
return ret;
ret = usb_ep_enable(dev->ep_out);
if (ret) {
usb_ep_disable(dev->ep_in);
return ret;
}
ret = config_ep_by_speed(cdev->gadget, f, dev->ep_intr);
if (ret)
return ret;
ret = usb_ep_enable(dev->ep_intr);
if (ret) {
usb_ep_disable(dev->ep_out);
usb_ep_disable(dev->ep_in);
return ret;
}
dev->state = STATE_READY;
/* readers may be blocked waiting for us to go online */
wake_up(&dev->read_wq);
return 0;
}
static void mtp_function_disable(struct usb_function *f)
{
struct mtp_dev *dev = func_to_mtp(f);
struct usb_composite_dev *cdev = dev->cdev;
DBG(cdev, "mtp_function_disable\n");
dev->state = STATE_OFFLINE;
usb_ep_disable(dev->ep_in);
usb_ep_disable(dev->ep_out);
usb_ep_disable(dev->ep_intr);
/* readers may be blocked waiting for us to go online */
wake_up(&dev->read_wq);
VDBG(cdev, "%s disabled\n", dev->function.name);
}
static int mtp_bind_config(struct usb_configuration *c, bool ptp_config)
{
struct mtp_dev *dev = _mtp_dev;
int ret = 0;
printk(KERN_INFO "mtp_bind_config\n");
/* allocate a string ID for our interface */
if (mtp_string_defs[INTERFACE_STRING_INDEX].id == 0) {
ret = usb_string_id(c->cdev);
if (ret < 0)
return ret;
mtp_string_defs[INTERFACE_STRING_INDEX].id = ret;
mtp_interface_desc.iInterface = ret;
}
dev->cdev = c->cdev;
dev->function.name = "mtp";
dev->function.strings = mtp_strings;
if (ptp_config) {
dev->function.fs_descriptors = fs_ptp_descs;
dev->function.hs_descriptors = hs_ptp_descs;
} else {
dev->function.fs_descriptors = fs_mtp_descs;
dev->function.hs_descriptors = hs_mtp_descs;
}
dev->function.bind = mtp_function_bind;
dev->function.unbind = mtp_function_unbind;
dev->function.set_alt = mtp_function_set_alt;
dev->function.disable = mtp_function_disable;
return usb_add_function(c, &dev->function);
}
static int mtp_setup(void)
{
struct mtp_dev *dev;
int ret;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
spin_lock_init(&dev->lock);
init_waitqueue_head(&dev->read_wq);
init_waitqueue_head(&dev->write_wq);
init_waitqueue_head(&dev->intr_wq);
atomic_set(&dev->open_excl, 0);
atomic_set(&dev->ioctl_excl, 0);
INIT_LIST_HEAD(&dev->tx_idle);
INIT_LIST_HEAD(&dev->intr_idle);
dev->wq = create_singlethread_workqueue("f_mtp");
if (!dev->wq) {
ret = -ENOMEM;
goto err1;
}
INIT_WORK(&dev->send_file_work, send_file_work);
INIT_WORK(&dev->receive_file_work, receive_file_work);
_mtp_dev = dev;
ret = misc_register(&mtp_device);
if (ret)
goto err2;
return 0;
err2:
destroy_workqueue(dev->wq);
err1:
_mtp_dev = NULL;
kfree(dev);
printk(KERN_ERR "mtp gadget driver failed to initialize\n");
return ret;
}
static void mtp_cleanup(void)
{
struct mtp_dev *dev = _mtp_dev;
if (!dev)
return;
misc_deregister(&mtp_device);
destroy_workqueue(dev->wq);
_mtp_dev = NULL;
kfree(dev);
}
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