blob: 59831d709e08c224e26d09704359a45cb853e5d3 [file] [log] [blame]
/*
* Gadget Function Driver for Android USB accessories
*
* Copyright (C) 2011 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/kthread.h>
#include <linux/freezer.h>
#include <linux/types.h>
#include <linux/file.h>
#include <linux/device.h>
#include <linux/miscdevice.h>
#include <linux/hid.h>
#include <linux/hiddev.h>
#include <linux/usb.h>
#include <linux/usb/ch9.h>
#include <linux/usb/f_accessory.h>
#include <linux/configfs.h>
#include <linux/usb/composite.h>
#define MAX_INST_NAME_LEN 40
#define BULK_BUFFER_SIZE 16384
#define ACC_STRING_SIZE 256
#define PROTOCOL_VERSION 2
/* String IDs */
#define INTERFACE_STRING_INDEX 0
/* number of tx and rx requests to allocate */
#define TX_REQ_MAX 4
#define RX_REQ_MAX 2
struct acc_hid_dev {
struct list_head list;
struct hid_device *hid;
struct acc_dev *dev;
/* accessory defined ID */
int id;
/* HID report descriptor */
u8 *report_desc;
/* length of HID report descriptor */
int report_desc_len;
/* number of bytes of report_desc we have received so far */
int report_desc_offset;
};
struct acc_dev {
struct usb_function function;
struct usb_composite_dev *cdev;
spinlock_t lock;
struct usb_ep *ep_in;
struct usb_ep *ep_out;
/* online indicates state of function_set_alt & function_unbind
* set to 1 when we connect
*/
int online:1;
/* disconnected indicates state of open & release
* Set to 1 when we disconnect.
* Not cleared until our file is closed.
*/
int disconnected:1;
/* strings sent by the host */
char manufacturer[ACC_STRING_SIZE];
char model[ACC_STRING_SIZE];
char description[ACC_STRING_SIZE];
char version[ACC_STRING_SIZE];
char uri[ACC_STRING_SIZE];
char serial[ACC_STRING_SIZE];
/* for acc_complete_set_string */
int string_index;
/* set to 1 if we have a pending start request */
int start_requested;
int audio_mode;
/* synchronize access to our device file */
atomic_t open_excl;
struct list_head tx_idle;
wait_queue_head_t read_wq;
wait_queue_head_t write_wq;
struct usb_request *rx_req[RX_REQ_MAX];
int rx_done;
/* delayed work for handling ACCESSORY_START */
struct delayed_work start_work;
/* worker for registering and unregistering hid devices */
struct work_struct hid_work;
/* list of active HID devices */
struct list_head hid_list;
/* list of new HID devices to register */
struct list_head new_hid_list;
/* list of dead HID devices to unregister */
struct list_head dead_hid_list;
};
static struct usb_interface_descriptor acc_interface_desc = {
.bLength = USB_DT_INTERFACE_SIZE,
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = 0,
.bNumEndpoints = 2,
.bInterfaceClass = USB_CLASS_VENDOR_SPEC,
.bInterfaceSubClass = USB_SUBCLASS_VENDOR_SPEC,
.bInterfaceProtocol = 0,
};
static struct usb_endpoint_descriptor acc_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 acc_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 acc_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 acc_fullspeed_out_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
};
static struct usb_descriptor_header *fs_acc_descs[] = {
(struct usb_descriptor_header *) &acc_interface_desc,
(struct usb_descriptor_header *) &acc_fullspeed_in_desc,
(struct usb_descriptor_header *) &acc_fullspeed_out_desc,
NULL,
};
static struct usb_descriptor_header *hs_acc_descs[] = {
(struct usb_descriptor_header *) &acc_interface_desc,
(struct usb_descriptor_header *) &acc_highspeed_in_desc,
(struct usb_descriptor_header *) &acc_highspeed_out_desc,
NULL,
};
static struct usb_string acc_string_defs[] = {
[INTERFACE_STRING_INDEX].s = "Android Accessory Interface",
{ }, /* end of list */
};
static struct usb_gadget_strings acc_string_table = {
.language = 0x0409, /* en-US */
.strings = acc_string_defs,
};
static struct usb_gadget_strings *acc_strings[] = {
&acc_string_table,
NULL,
};
static struct acc_dev *_acc_dev;
struct acc_instance {
struct usb_function_instance func_inst;
const char *name;
};
static inline struct acc_dev *func_to_dev(struct usb_function *f)
{
return container_of(f, struct acc_dev, function);
}
static struct usb_request *acc_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 acc_request_free(struct usb_request *req, struct usb_ep *ep)
{
if (req) {
kfree(req->buf);
usb_ep_free_request(ep, req);
}
}
/* add a request to the tail of a list */
static void req_put(struct acc_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 *req_get(struct acc_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 acc_set_disconnected(struct acc_dev *dev)
{
dev->disconnected = 1;
}
static void acc_complete_in(struct usb_ep *ep, struct usb_request *req)
{
struct acc_dev *dev = _acc_dev;
if (req->status == -ESHUTDOWN) {
pr_debug("acc_complete_in set disconnected");
acc_set_disconnected(dev);
}
req_put(dev, &dev->tx_idle, req);
wake_up(&dev->write_wq);
}
static void acc_complete_out(struct usb_ep *ep, struct usb_request *req)
{
struct acc_dev *dev = _acc_dev;
dev->rx_done = 1;
if (req->status == -ESHUTDOWN) {
pr_debug("acc_complete_out set disconnected");
acc_set_disconnected(dev);
}
wake_up(&dev->read_wq);
}
static void acc_complete_set_string(struct usb_ep *ep, struct usb_request *req)
{
struct acc_dev *dev = ep->driver_data;
char *string_dest = NULL;
int length = req->actual;
if (req->status != 0) {
pr_err("acc_complete_set_string, err %d\n", req->status);
return;
}
switch (dev->string_index) {
case ACCESSORY_STRING_MANUFACTURER:
string_dest = dev->manufacturer;
break;
case ACCESSORY_STRING_MODEL:
string_dest = dev->model;
break;
case ACCESSORY_STRING_DESCRIPTION:
string_dest = dev->description;
break;
case ACCESSORY_STRING_VERSION:
string_dest = dev->version;
break;
case ACCESSORY_STRING_URI:
string_dest = dev->uri;
break;
case ACCESSORY_STRING_SERIAL:
string_dest = dev->serial;
break;
}
if (string_dest) {
unsigned long flags;
if (length >= ACC_STRING_SIZE)
length = ACC_STRING_SIZE - 1;
spin_lock_irqsave(&dev->lock, flags);
memcpy(string_dest, req->buf, length);
/* ensure zero termination */
string_dest[length] = 0;
spin_unlock_irqrestore(&dev->lock, flags);
} else {
pr_err("unknown accessory string index %d\n",
dev->string_index);
}
}
static void acc_complete_set_hid_report_desc(struct usb_ep *ep,
struct usb_request *req)
{
struct acc_hid_dev *hid = req->context;
struct acc_dev *dev = hid->dev;
int length = req->actual;
if (req->status != 0) {
pr_err("acc_complete_set_hid_report_desc, err %d\n",
req->status);
return;
}
memcpy(hid->report_desc + hid->report_desc_offset, req->buf, length);
hid->report_desc_offset += length;
if (hid->report_desc_offset == hid->report_desc_len) {
/* After we have received the entire report descriptor
* we schedule work to initialize the HID device
*/
schedule_work(&dev->hid_work);
}
}
static void acc_complete_send_hid_event(struct usb_ep *ep,
struct usb_request *req)
{
struct acc_hid_dev *hid = req->context;
int length = req->actual;
if (req->status != 0) {
pr_err("acc_complete_send_hid_event, err %d\n", req->status);
return;
}
hid_report_raw_event(hid->hid, HID_INPUT_REPORT, req->buf, length, 1);
}
static int acc_hid_parse(struct hid_device *hid)
{
struct acc_hid_dev *hdev = hid->driver_data;
hid_parse_report(hid, hdev->report_desc, hdev->report_desc_len);
return 0;
}
static int acc_hid_start(struct hid_device *hid)
{
return 0;
}
static void acc_hid_stop(struct hid_device *hid)
{
}
static int acc_hid_open(struct hid_device *hid)
{
return 0;
}
static void acc_hid_close(struct hid_device *hid)
{
}
static int acc_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
__u8 *buf, size_t len, unsigned char rtype, int reqtype)
{
return 0;
}
static struct hid_ll_driver acc_hid_ll_driver = {
.parse = acc_hid_parse,
.start = acc_hid_start,
.stop = acc_hid_stop,
.open = acc_hid_open,
.close = acc_hid_close,
.raw_request = acc_hid_raw_request,
};
static struct acc_hid_dev *acc_hid_new(struct acc_dev *dev,
int id, int desc_len)
{
struct acc_hid_dev *hdev;
hdev = kzalloc(sizeof(*hdev), GFP_ATOMIC);
if (!hdev)
return NULL;
hdev->report_desc = kzalloc(desc_len, GFP_ATOMIC);
if (!hdev->report_desc) {
kfree(hdev);
return NULL;
}
hdev->dev = dev;
hdev->id = id;
hdev->report_desc_len = desc_len;
return hdev;
}
static struct acc_hid_dev *acc_hid_get(struct list_head *list, int id)
{
struct acc_hid_dev *hid;
list_for_each_entry(hid, list, list) {
if (hid->id == id)
return hid;
}
return NULL;
}
static int acc_register_hid(struct acc_dev *dev, int id, int desc_length)
{
struct acc_hid_dev *hid;
unsigned long flags;
/* report descriptor length must be > 0 */
if (desc_length <= 0)
return -EINVAL;
spin_lock_irqsave(&dev->lock, flags);
/* replace HID if one already exists with this ID */
hid = acc_hid_get(&dev->hid_list, id);
if (!hid)
hid = acc_hid_get(&dev->new_hid_list, id);
if (hid)
list_move(&hid->list, &dev->dead_hid_list);
hid = acc_hid_new(dev, id, desc_length);
if (!hid) {
spin_unlock_irqrestore(&dev->lock, flags);
return -ENOMEM;
}
list_add(&hid->list, &dev->new_hid_list);
spin_unlock_irqrestore(&dev->lock, flags);
/* schedule work to register the HID device */
schedule_work(&dev->hid_work);
return 0;
}
static int acc_unregister_hid(struct acc_dev *dev, int id)
{
struct acc_hid_dev *hid;
unsigned long flags;
spin_lock_irqsave(&dev->lock, flags);
hid = acc_hid_get(&dev->hid_list, id);
if (!hid)
hid = acc_hid_get(&dev->new_hid_list, id);
if (!hid) {
spin_unlock_irqrestore(&dev->lock, flags);
return -EINVAL;
}
list_move(&hid->list, &dev->dead_hid_list);
spin_unlock_irqrestore(&dev->lock, flags);
schedule_work(&dev->hid_work);
return 0;
}
static int create_bulk_endpoints(struct acc_dev *dev,
struct usb_endpoint_descriptor *in_desc,
struct usb_endpoint_descriptor *out_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 ep_out got %s\n", ep->name);
ep->driver_data = dev; /* claim the endpoint */
dev->ep_out = ep;
/* now allocate requests for our endpoints */
for (i = 0; i < TX_REQ_MAX; i++) {
req = acc_request_new(dev->ep_in, BULK_BUFFER_SIZE);
if (!req)
goto fail;
req->complete = acc_complete_in;
req_put(dev, &dev->tx_idle, req);
}
for (i = 0; i < RX_REQ_MAX; i++) {
req = acc_request_new(dev->ep_out, BULK_BUFFER_SIZE);
if (!req)
goto fail;
req->complete = acc_complete_out;
dev->rx_req[i] = req;
}
return 0;
fail:
pr_err("acc_bind() could not allocate requests\n");
while ((req = req_get(dev, &dev->tx_idle)))
acc_request_free(req, dev->ep_in);
for (i = 0; i < RX_REQ_MAX; i++)
acc_request_free(dev->rx_req[i], dev->ep_out);
return -1;
}
static ssize_t acc_read(struct file *fp, char __user *buf,
size_t count, loff_t *pos)
{
struct acc_dev *dev = fp->private_data;
struct usb_request *req;
ssize_t r = count;
ssize_t data_length;
unsigned xfer;
int ret = 0;
pr_debug("acc_read(%zu)\n", count);
if (dev->disconnected) {
pr_debug("acc_read disconnected");
return -ENODEV;
}
if (count > BULK_BUFFER_SIZE)
count = BULK_BUFFER_SIZE;
/* we will block until we're online */
pr_debug("acc_read: waiting for online\n");
ret = wait_event_interruptible(dev->read_wq, dev->online);
if (ret < 0) {
r = ret;
goto done;
}
/*
* Calculate the data length by considering termination character.
* Then compansite the difference of rounding up to
* integer multiple of maxpacket size.
*/
data_length = count;
data_length += dev->ep_out->maxpacket - 1;
data_length -= data_length % dev->ep_out->maxpacket;
if (dev->rx_done) {
// last req cancelled. try to get it.
req = dev->rx_req[0];
goto copy_data;
}
requeue_req:
/* queue a request */
req = dev->rx_req[0];
req->length = data_length;
dev->rx_done = 0;
ret = usb_ep_queue(dev->ep_out, req, GFP_KERNEL);
if (ret < 0) {
r = -EIO;
goto done;
} else {
pr_debug("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;
ret = usb_ep_dequeue(dev->ep_out, req);
if (ret != 0) {
// cancel failed. There can be a data already received.
// it will be retrieved in the next read.
pr_debug("acc_read: cancelling failed %d", ret);
}
goto done;
}
copy_data:
dev->rx_done = 0;
if (dev->online) {
/* If we got a 0-len packet, throw it back and try again. */
if (req->actual == 0)
goto requeue_req;
pr_debug("rx %p %u\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:
pr_debug("acc_read returning %zd\n", r);
return r;
}
static ssize_t acc_write(struct file *fp, const char __user *buf,
size_t count, loff_t *pos)
{
struct acc_dev *dev = fp->private_data;
struct usb_request *req = 0;
ssize_t r = count;
unsigned xfer;
int ret;
pr_debug("acc_write(%zu)\n", count);
if (!dev->online || dev->disconnected) {
pr_debug("acc_write disconnected or not online");
return -ENODEV;
}
while (count > 0) {
if (!dev->online) {
pr_debug("acc_write dev->error\n");
r = -EIO;
break;
}
/* get an idle tx request to use */
req = 0;
ret = wait_event_interruptible(dev->write_wq,
((req = req_get(dev, &dev->tx_idle)) || !dev->online));
if (!req) {
r = ret;
break;
}
if (count > BULK_BUFFER_SIZE) {
xfer = BULK_BUFFER_SIZE;
/* ZLP, They will be more TX requests so not yet. */
req->zero = 0;
} else {
xfer = count;
/* If the data length is a multple of the
* maxpacket size then send a zero length packet(ZLP).
*/
req->zero = ((xfer % dev->ep_in->maxpacket) == 0);
}
if (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) {
pr_debug("acc_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)
req_put(dev, &dev->tx_idle, req);
pr_debug("acc_write returning %zd\n", r);
return r;
}
static long acc_ioctl(struct file *fp, unsigned code, unsigned long value)
{
struct acc_dev *dev = fp->private_data;
char *src = NULL;
int ret;
switch (code) {
case ACCESSORY_GET_STRING_MANUFACTURER:
src = dev->manufacturer;
break;
case ACCESSORY_GET_STRING_MODEL:
src = dev->model;
break;
case ACCESSORY_GET_STRING_DESCRIPTION:
src = dev->description;
break;
case ACCESSORY_GET_STRING_VERSION:
src = dev->version;
break;
case ACCESSORY_GET_STRING_URI:
src = dev->uri;
break;
case ACCESSORY_GET_STRING_SERIAL:
src = dev->serial;
break;
case ACCESSORY_IS_START_REQUESTED:
return dev->start_requested;
case ACCESSORY_GET_AUDIO_MODE:
return dev->audio_mode;
}
if (!src)
return -EINVAL;
ret = strlen(src) + 1;
if (copy_to_user((void __user *)value, src, ret))
ret = -EFAULT;
return ret;
}
static int acc_open(struct inode *ip, struct file *fp)
{
if (atomic_xchg(&_acc_dev->open_excl, 1))
return -EBUSY;
_acc_dev->disconnected = 0;
fp->private_data = _acc_dev;
return 0;
}
static int acc_release(struct inode *ip, struct file *fp)
{
WARN_ON(!atomic_xchg(&_acc_dev->open_excl, 0));
/* indicate that we are disconnected
* still could be online so don't touch online flag
*/
_acc_dev->disconnected = 1;
return 0;
}
/* file operations for /dev/usb_accessory */
static const struct file_operations acc_fops = {
.owner = THIS_MODULE,
.read = acc_read,
.write = acc_write,
.unlocked_ioctl = acc_ioctl,
.open = acc_open,
.release = acc_release,
};
static int acc_hid_probe(struct hid_device *hdev,
const struct hid_device_id *id)
{
int ret;
ret = hid_parse(hdev);
if (ret)
return ret;
return hid_hw_start(hdev, HID_CONNECT_DEFAULT);
}
static struct miscdevice acc_device = {
.minor = MISC_DYNAMIC_MINOR,
.name = "usb_accessory",
.fops = &acc_fops,
};
static const struct hid_device_id acc_hid_table[] = {
{ HID_USB_DEVICE(HID_ANY_ID, HID_ANY_ID) },
{ }
};
static struct hid_driver acc_hid_driver = {
.name = "USB accessory",
.id_table = acc_hid_table,
.probe = acc_hid_probe,
};
static void acc_complete_setup_noop(struct usb_ep *ep, struct usb_request *req)
{
/*
* Default no-op function when nothing needs to be done for the
* setup request
*/
}
int acc_ctrlrequest(struct usb_composite_dev *cdev,
const struct usb_ctrlrequest *ctrl)
{
struct acc_dev *dev = _acc_dev;
int value = -EOPNOTSUPP;
struct acc_hid_dev *hid;
int offset;
u8 b_requestType = ctrl->bRequestType;
u8 b_request = ctrl->bRequest;
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;
/*
* If instance is not created which is the case in power off charging
* mode, dev will be NULL. Hence return error if it is the case.
*/
if (!dev)
return -ENODEV;
if (b_requestType == (USB_DIR_OUT | USB_TYPE_VENDOR)) {
if (b_request == ACCESSORY_START) {
dev->start_requested = 1;
schedule_delayed_work(
&dev->start_work, msecs_to_jiffies(10));
value = 0;
cdev->req->complete = acc_complete_setup_noop;
} else if (b_request == ACCESSORY_SEND_STRING) {
dev->string_index = w_index;
cdev->gadget->ep0->driver_data = dev;
cdev->req->complete = acc_complete_set_string;
value = w_length;
} else if (b_request == ACCESSORY_SET_AUDIO_MODE &&
w_index == 0 && w_length == 0) {
dev->audio_mode = w_value;
cdev->req->complete = acc_complete_setup_noop;
value = 0;
} else if (b_request == ACCESSORY_REGISTER_HID) {
cdev->req->complete = acc_complete_setup_noop;
value = acc_register_hid(dev, w_value, w_index);
} else if (b_request == ACCESSORY_UNREGISTER_HID) {
cdev->req->complete = acc_complete_setup_noop;
value = acc_unregister_hid(dev, w_value);
} else if (b_request == ACCESSORY_SET_HID_REPORT_DESC) {
spin_lock_irqsave(&dev->lock, flags);
hid = acc_hid_get(&dev->new_hid_list, w_value);
spin_unlock_irqrestore(&dev->lock, flags);
if (!hid) {
value = -EINVAL;
goto err;
}
offset = w_index;
if (offset != hid->report_desc_offset
|| offset + w_length > hid->report_desc_len) {
value = -EINVAL;
goto err;
}
cdev->req->context = hid;
cdev->req->complete = acc_complete_set_hid_report_desc;
value = w_length;
} else if (b_request == ACCESSORY_SEND_HID_EVENT) {
spin_lock_irqsave(&dev->lock, flags);
hid = acc_hid_get(&dev->hid_list, w_value);
spin_unlock_irqrestore(&dev->lock, flags);
if (!hid) {
value = -EINVAL;
goto err;
}
cdev->req->context = hid;
cdev->req->complete = acc_complete_send_hid_event;
value = w_length;
}
} else if (b_requestType == (USB_DIR_IN | USB_TYPE_VENDOR)) {
if (b_request == ACCESSORY_GET_PROTOCOL) {
*((u16 *)cdev->req->buf) = PROTOCOL_VERSION;
value = sizeof(u16);
cdev->req->complete = acc_complete_setup_noop;
/* clear any string left over from a previous session */
memset(dev->manufacturer, 0, sizeof(dev->manufacturer));
memset(dev->model, 0, sizeof(dev->model));
memset(dev->description, 0, sizeof(dev->description));
memset(dev->version, 0, sizeof(dev->version));
memset(dev->uri, 0, sizeof(dev->uri));
memset(dev->serial, 0, sizeof(dev->serial));
dev->start_requested = 0;
dev->audio_mode = 0;
}
}
if (value >= 0) {
cdev->req->zero = 0;
cdev->req->length = value;
value = usb_ep_queue(cdev->gadget->ep0, cdev->req, GFP_ATOMIC);
if (value < 0)
ERROR(cdev, "%s setup response queue error\n",
__func__);
}
err:
if (value == -EOPNOTSUPP)
VDBG(cdev,
"unknown class-specific control req "
"%02x.%02x v%04x i%04x l%u\n",
ctrl->bRequestType, ctrl->bRequest,
w_value, w_index, w_length);
return value;
}
EXPORT_SYMBOL_GPL(acc_ctrlrequest);
static int
__acc_function_bind(struct usb_configuration *c,
struct usb_function *f, bool configfs)
{
struct usb_composite_dev *cdev = c->cdev;
struct acc_dev *dev = func_to_dev(f);
int id;
int ret;
DBG(cdev, "acc_function_bind dev: %p\n", dev);
if (configfs) {
if (acc_string_defs[INTERFACE_STRING_INDEX].id == 0) {
ret = usb_string_id(c->cdev);
if (ret < 0)
return ret;
acc_string_defs[INTERFACE_STRING_INDEX].id = ret;
acc_interface_desc.iInterface = ret;
}
dev->cdev = c->cdev;
}
ret = hid_register_driver(&acc_hid_driver);
if (ret)
return ret;
dev->start_requested = 0;
/* allocate interface ID(s) */
id = usb_interface_id(c, f);
if (id < 0)
return id;
acc_interface_desc.bInterfaceNumber = id;
/* allocate endpoints */
ret = create_bulk_endpoints(dev, &acc_fullspeed_in_desc,
&acc_fullspeed_out_desc);
if (ret)
return ret;
/* support high speed hardware */
if (gadget_is_dualspeed(c->cdev->gadget)) {
acc_highspeed_in_desc.bEndpointAddress =
acc_fullspeed_in_desc.bEndpointAddress;
acc_highspeed_out_desc.bEndpointAddress =
acc_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 int
acc_function_bind_configfs(struct usb_configuration *c,
struct usb_function *f) {
return __acc_function_bind(c, f, true);
}
static void
kill_all_hid_devices(struct acc_dev *dev)
{
struct acc_hid_dev *hid;
struct list_head *entry, *temp;
unsigned long flags;
/* do nothing if usb accessory device doesn't exist */
if (!dev)
return;
spin_lock_irqsave(&dev->lock, flags);
list_for_each_safe(entry, temp, &dev->hid_list) {
hid = list_entry(entry, struct acc_hid_dev, list);
list_del(&hid->list);
list_add(&hid->list, &dev->dead_hid_list);
}
list_for_each_safe(entry, temp, &dev->new_hid_list) {
hid = list_entry(entry, struct acc_hid_dev, list);
list_del(&hid->list);
list_add(&hid->list, &dev->dead_hid_list);
}
spin_unlock_irqrestore(&dev->lock, flags);
schedule_work(&dev->hid_work);
}
static void
acc_hid_unbind(struct acc_dev *dev)
{
hid_unregister_driver(&acc_hid_driver);
kill_all_hid_devices(dev);
}
static void
acc_function_unbind(struct usb_configuration *c, struct usb_function *f)
{
struct acc_dev *dev = func_to_dev(f);
struct usb_request *req;
int i;
dev->online = 0; /* clear online flag */
wake_up(&dev->read_wq); /* unblock reads on closure */
wake_up(&dev->write_wq); /* likewise for writes */
while ((req = req_get(dev, &dev->tx_idle)))
acc_request_free(req, dev->ep_in);
for (i = 0; i < RX_REQ_MAX; i++)
acc_request_free(dev->rx_req[i], dev->ep_out);
acc_hid_unbind(dev);
}
static void acc_start_work(struct work_struct *data)
{
char *envp[2] = { "ACCESSORY=START", NULL };
kobject_uevent_env(&acc_device.this_device->kobj, KOBJ_CHANGE, envp);
}
static int acc_hid_init(struct acc_hid_dev *hdev)
{
struct hid_device *hid;
int ret;
hid = hid_allocate_device();
if (IS_ERR(hid))
return PTR_ERR(hid);
hid->ll_driver = &acc_hid_ll_driver;
hid->dev.parent = acc_device.this_device;
hid->bus = BUS_USB;
hid->vendor = HID_ANY_ID;
hid->product = HID_ANY_ID;
hid->driver_data = hdev;
ret = hid_add_device(hid);
if (ret) {
pr_err("can't add hid device: %d\n", ret);
hid_destroy_device(hid);
return ret;
}
hdev->hid = hid;
return 0;
}
static void acc_hid_delete(struct acc_hid_dev *hid)
{
kfree(hid->report_desc);
kfree(hid);
}
static void acc_hid_work(struct work_struct *data)
{
struct acc_dev *dev = _acc_dev;
struct list_head *entry, *temp;
struct acc_hid_dev *hid;
struct list_head new_list, dead_list;
unsigned long flags;
INIT_LIST_HEAD(&new_list);
spin_lock_irqsave(&dev->lock, flags);
/* copy hids that are ready for initialization to new_list */
list_for_each_safe(entry, temp, &dev->new_hid_list) {
hid = list_entry(entry, struct acc_hid_dev, list);
if (hid->report_desc_offset == hid->report_desc_len)
list_move(&hid->list, &new_list);
}
if (list_empty(&dev->dead_hid_list)) {
INIT_LIST_HEAD(&dead_list);
} else {
/* move all of dev->dead_hid_list to dead_list */
dead_list.prev = dev->dead_hid_list.prev;
dead_list.next = dev->dead_hid_list.next;
dead_list.next->prev = &dead_list;
dead_list.prev->next = &dead_list;
INIT_LIST_HEAD(&dev->dead_hid_list);
}
spin_unlock_irqrestore(&dev->lock, flags);
/* register new HID devices */
list_for_each_safe(entry, temp, &new_list) {
hid = list_entry(entry, struct acc_hid_dev, list);
if (acc_hid_init(hid)) {
pr_err("can't add HID device %p\n", hid);
acc_hid_delete(hid);
} else {
spin_lock_irqsave(&dev->lock, flags);
list_move(&hid->list, &dev->hid_list);
spin_unlock_irqrestore(&dev->lock, flags);
}
}
/* remove dead HID devices */
list_for_each_safe(entry, temp, &dead_list) {
hid = list_entry(entry, struct acc_hid_dev, list);
list_del(&hid->list);
if (hid->hid)
hid_destroy_device(hid->hid);
acc_hid_delete(hid);
}
}
static int acc_function_set_alt(struct usb_function *f,
unsigned intf, unsigned alt)
{
struct acc_dev *dev = func_to_dev(f);
struct usb_composite_dev *cdev = f->config->cdev;
int ret;
DBG(cdev, "acc_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;
}
dev->online = 1;
dev->disconnected = 0; /* if online then not disconnected */
/* readers may be blocked waiting for us to go online */
wake_up(&dev->read_wq);
return 0;
}
static void acc_function_disable(struct usb_function *f)
{
struct acc_dev *dev = func_to_dev(f);
struct usb_composite_dev *cdev = dev->cdev;
DBG(cdev, "acc_function_disable\n");
acc_set_disconnected(dev); /* this now only sets disconnected */
dev->online = 0; /* so now need to clear online flag here too */
usb_ep_disable(dev->ep_in);
usb_ep_disable(dev->ep_out);
/* 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 acc_setup(void)
{
struct acc_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);
atomic_set(&dev->open_excl, 0);
INIT_LIST_HEAD(&dev->tx_idle);
INIT_LIST_HEAD(&dev->hid_list);
INIT_LIST_HEAD(&dev->new_hid_list);
INIT_LIST_HEAD(&dev->dead_hid_list);
INIT_DELAYED_WORK(&dev->start_work, acc_start_work);
INIT_WORK(&dev->hid_work, acc_hid_work);
_acc_dev = dev;
ret = misc_register(&acc_device);
if (ret)
goto err;
return 0;
err:
kfree(dev);
pr_err("USB accessory gadget driver failed to initialize\n");
return ret;
}
void acc_disconnect(void)
{
/* unregister all HID devices if USB is disconnected */
kill_all_hid_devices(_acc_dev);
}
EXPORT_SYMBOL_GPL(acc_disconnect);
static void acc_cleanup(void)
{
misc_deregister(&acc_device);
kfree(_acc_dev);
_acc_dev = NULL;
}
static struct acc_instance *to_acc_instance(struct config_item *item)
{
return container_of(to_config_group(item), struct acc_instance,
func_inst.group);
}
static void acc_attr_release(struct config_item *item)
{
struct acc_instance *fi_acc = to_acc_instance(item);
usb_put_function_instance(&fi_acc->func_inst);
}
static struct configfs_item_operations acc_item_ops = {
.release = acc_attr_release,
};
static struct config_item_type acc_func_type = {
.ct_item_ops = &acc_item_ops,
.ct_owner = THIS_MODULE,
};
static struct acc_instance *to_fi_acc(struct usb_function_instance *fi)
{
return container_of(fi, struct acc_instance, func_inst);
}
static int acc_set_inst_name(struct usb_function_instance *fi, const char *name)
{
struct acc_instance *fi_acc;
char *ptr;
int name_len;
name_len = strlen(name) + 1;
if (name_len > MAX_INST_NAME_LEN)
return -ENAMETOOLONG;
ptr = kstrndup(name, name_len, GFP_KERNEL);
if (!ptr)
return -ENOMEM;
fi_acc = to_fi_acc(fi);
fi_acc->name = ptr;
return 0;
}
static void acc_free_inst(struct usb_function_instance *fi)
{
struct acc_instance *fi_acc;
fi_acc = to_fi_acc(fi);
kfree(fi_acc->name);
acc_cleanup();
}
static struct usb_function_instance *acc_alloc_inst(void)
{
struct acc_instance *fi_acc;
int err;
fi_acc = kzalloc(sizeof(*fi_acc), GFP_KERNEL);
if (!fi_acc)
return ERR_PTR(-ENOMEM);
fi_acc->func_inst.set_inst_name = acc_set_inst_name;
fi_acc->func_inst.free_func_inst = acc_free_inst;
err = acc_setup();
if (err) {
kfree(fi_acc);
return ERR_PTR(err);
}
config_group_init_type_name(&fi_acc->func_inst.group,
"", &acc_func_type);
return &fi_acc->func_inst;
}
static void acc_free(struct usb_function *f)
{
/*NO-OP: no function specific resource allocation in mtp_alloc*/
}
int acc_ctrlrequest_configfs(struct usb_function *f,
const struct usb_ctrlrequest *ctrl) {
if (f->config != NULL && f->config->cdev != NULL)
return acc_ctrlrequest(f->config->cdev, ctrl);
else
return -1;
}
static struct usb_function *acc_alloc(struct usb_function_instance *fi)
{
struct acc_dev *dev = _acc_dev;
dev->function.name = "accessory";
dev->function.strings = acc_strings,
dev->function.fs_descriptors = fs_acc_descs;
dev->function.hs_descriptors = hs_acc_descs;
dev->function.bind = acc_function_bind_configfs;
dev->function.unbind = acc_function_unbind;
dev->function.set_alt = acc_function_set_alt;
dev->function.disable = acc_function_disable;
dev->function.free_func = acc_free;
dev->function.setup = acc_ctrlrequest_configfs;
return &dev->function;
}
DECLARE_USB_FUNCTION_INIT(accessory, acc_alloc_inst, acc_alloc);
MODULE_LICENSE("GPL");