--- /dev/null
+/*
+ * 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/usb.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/f_accessory.h>
+
+#define BULK_BUFFER_SIZE 16384
+#define ACC_STRING_SIZE 256
+
+#define PROTOCOL_VERSION 1
+
+/* 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_dev {
+ struct usb_function function;
+ struct usb_composite_dev *cdev;
+ spinlock_t lock;
+
+ struct usb_ep *ep_in;
+ struct usb_ep *ep_out;
+
+ /* set to 1 when we connect */
+ int online:1;
+ /* 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;
+
+ /* 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;
+ struct delayed_work work;
+};
+
+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,
+};
+
+/* temporary variable used between acc_open() and acc_gadget_bind() */
+static struct acc_dev *_acc_dev;
+
+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->online = 0;
+ 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 != 0)
+ 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 != 0)
+ 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 int __init 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;
+
+ 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:
+ printk(KERN_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;
+ int r = count, xfer;
+ int ret = 0;
+
+ pr_debug("acc_read(%d)\n", count);
+
+ if (dev->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;
+ }
+
+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 {
+ 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;
+ usb_ep_dequeue(dev->ep_out, req);
+ goto done;
+ }
+ 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 %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:
+ pr_debug("acc_read returning %d\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;
+ int r = count, xfer;
+ int ret;
+
+ pr_debug("acc_write(%d)\n", count);
+
+ if (!dev->online || dev->disconnected)
+ 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;
+ else
+ xfer = count;
+ 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 %d\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;
+ }
+ 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)
+{
+ printk(KERN_INFO "acc_open\n");
+ 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)
+{
+ printk(KERN_INFO "acc_release\n");
+
+ WARN_ON(!atomic_xchg(&_acc_dev->open_excl, 0));
+ _acc_dev->disconnected = 0;
+ return 0;
+}
+
+/* file operations for /dev/acc_usb */
+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 struct miscdevice acc_device = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "usb_accessory",
+ .fops = &acc_fops,
+};
+
+
+static int acc_ctrlrequest(struct usb_composite_dev *cdev,
+ const struct usb_ctrlrequest *ctrl)
+{
+ struct acc_dev *dev = _acc_dev;
+ int value = -EOPNOTSUPP;
+ 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);
+
+/*
+ printk(KERN_INFO "acc_ctrlrequest "
+ "%02x.%02x v%04x i%04x l%u\n",
+ b_requestType, b_request,
+ w_value, w_index, w_length);
+*/
+
+ if (b_requestType == (USB_DIR_OUT | USB_TYPE_VENDOR)) {
+ if (b_request == ACCESSORY_START) {
+ dev->start_requested = 1;
+ schedule_delayed_work(
+ &dev->work, msecs_to_jiffies(10));
+ value = 0;
+ } 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_requestType == (USB_DIR_IN | USB_TYPE_VENDOR)) {
+ if (b_request == ACCESSORY_GET_PROTOCOL) {
+ *((u16 *)cdev->req->buf) = PROTOCOL_VERSION;
+ value = sizeof(u16);
+
+ /* 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;
+ }
+ }
+
+ 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__);
+ }
+
+ 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;
+}
+
+static int
+acc_function_bind(struct usb_configuration *c, struct usb_function *f)
+{
+ 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);
+
+ 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 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;
+
+ 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);
+}
+
+static void acc_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_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;
+
+ /* 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);
+ 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_bind_config(struct usb_configuration *c)
+{
+ struct acc_dev *dev = _acc_dev;
+ int ret;
+
+ printk(KERN_INFO "acc_bind_config\n");
+
+ /* allocate a string ID for our interface */
+ 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;
+ dev->function.name = "accessory";
+ dev->function.strings = acc_strings,
+ dev->function.descriptors = fs_acc_descs;
+ dev->function.hs_descriptors = hs_acc_descs;
+ dev->function.bind = acc_function_bind;
+ dev->function.unbind = acc_function_unbind;
+ dev->function.set_alt = acc_function_set_alt;
+ dev->function.disable = acc_function_disable;
+
+ return usb_add_function(c, &dev->function);
+}
+
+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_DELAYED_WORK(&dev->work, acc_work);
+
+ /* _acc_dev must be set before calling usb_gadget_register_driver */
+ _acc_dev = dev;
+
+ ret = misc_register(&acc_device);
+ if (ret)
+ goto err;
+
+ return 0;
+
+err:
+ kfree(dev);
+ printk(KERN_ERR "USB accessory gadget driver failed to initialize\n");
+ return ret;
+}
+
+static void acc_cleanup(void)
+{
+ misc_deregister(&acc_device);
+ kfree(_acc_dev);
+ _acc_dev = NULL;
+}
projects / firefly-linux-kernel-4.4.55.git / commitdiff