1 files changed, 609 insertions, 0 deletions

diff --git a/drivers/usb/gadget/f_adb.c b/drivers/usb/gadget/f_adb.c
new file mode 100644
index 000000000000..30b0a0cc291d
--- /dev/null
+++ b/drivers/usb/gadget/f_adb.c
@@ -0,0 +1,609 @@
+/*
+ * Gadget Driver for Android ADB
+ *
+ * Copyright (C) 2008 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.
+ *
+ */
+
+#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/sched.h>
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/miscdevice.h>
+
+#define ADB_BULK_BUFFER_SIZE           4096
+
+/* number of tx requests to allocate */
+#define TX_REQ_MAX 4
+
+static const char adb_shortname[] = "android_adb";
+
+struct adb_dev {
+	struct usb_function function;
+	struct usb_composite_dev *cdev;
+	spinlock_t lock;
+
+	struct usb_ep *ep_in;
+	struct usb_ep *ep_out;
+
+	int online;
+	int error;
+
+	atomic_t read_excl;
+	atomic_t write_excl;
+	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;
+	int rx_done;
+};
+
+static struct usb_interface_descriptor adb_interface_desc = {
+	.bLength                = USB_DT_INTERFACE_SIZE,
+	.bDescriptorType        = USB_DT_INTERFACE,
+	.bInterfaceNumber       = 0,
+	.bNumEndpoints          = 2,
+	.bInterfaceClass        = 0xFF,
+	.bInterfaceSubClass     = 0x42,
+	.bInterfaceProtocol     = 1,
+};
+
+static struct usb_endpoint_descriptor adb_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 adb_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 adb_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 adb_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_adb_descs[] = {
+	(struct usb_descriptor_header *) &adb_interface_desc,
+	(struct usb_descriptor_header *) &adb_fullspeed_in_desc,
+	(struct usb_descriptor_header *) &adb_fullspeed_out_desc,
+	NULL,
+};
+
+static struct usb_descriptor_header *hs_adb_descs[] = {
+	(struct usb_descriptor_header *) &adb_interface_desc,
+	(struct usb_descriptor_header *) &adb_highspeed_in_desc,
+	(struct usb_descriptor_header *) &adb_highspeed_out_desc,
+	NULL,
+};
+
+
+/* temporary variable used between adb_open() and adb_gadget_bind() */
+static struct adb_dev *_adb_dev;
+
+static inline struct adb_dev *func_to_adb(struct usb_function *f)
+{
+	return container_of(f, struct adb_dev, function);
+}
+
+
+static struct usb_request *adb_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 adb_request_free(struct usb_request *req, struct usb_ep *ep)
+{
+	if (req) {
+		kfree(req->buf);
+		usb_ep_free_request(ep, req);
+	}
+}
+
+static inline int adb_lock(atomic_t *excl)
+{
+	if (atomic_inc_return(excl) == 1) {
+		return 0;
+	} else {
+		atomic_dec(excl);
+		return -1;
+	}
+}
+
+static inline void adb_unlock(atomic_t *excl)
+{
+	atomic_dec(excl);
+}
+
+/* add a request to the tail of a list */
+void adb_req_put(struct adb_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 */
+struct usb_request *adb_req_get(struct adb_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 adb_complete_in(struct usb_ep *ep, struct usb_request *req)
+{
+	struct adb_dev *dev = _adb_dev;
+
+	if (req->status != 0)
+		dev->error = 1;
+
+	adb_req_put(dev, &dev->tx_idle, req);
+
+	wake_up(&dev->write_wq);
+}
+
+static void adb_complete_out(struct usb_ep *ep, struct usb_request *req)
+{
+	struct adb_dev *dev = _adb_dev;
+
+	dev->rx_done = 1;
+	if (req->status != 0)
+		dev->error = 1;
+
+	wake_up(&dev->read_wq);
+}
+
+static int adb_create_bulk_endpoints(struct adb_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 adb ep_out got %s\n", ep->name);
+	ep->driver_data = dev;		/* claim the endpoint */
+	dev->ep_out = ep;
+
+	/* now allocate requests for our endpoints */
+	req = adb_request_new(dev->ep_out, ADB_BULK_BUFFER_SIZE);
+	if (!req)
+		goto fail;
+	req->complete = adb_complete_out;
+	dev->rx_req = req;
+
+	for (i = 0; i < TX_REQ_MAX; i++) {
+		req = adb_request_new(dev->ep_in, ADB_BULK_BUFFER_SIZE);
+		if (!req)
+			goto fail;
+		req->complete = adb_complete_in;
+		adb_req_put(dev, &dev->tx_idle, req);
+	}
+
+	return 0;
+
+fail:
+	printk(KERN_ERR "adb_bind() could not allocate requests\n");
+	return -1;
+}
+
+static ssize_t adb_read(struct file *fp, char __user *buf,
+				size_t count, loff_t *pos)
+{
+	struct adb_dev *dev = fp->private_data;
+	struct usb_request *req;
+	int r = count, xfer;
+	int ret;
+
+	pr_debug("adb_read(%d)\n", count);
+	if (!_adb_dev)
+		return -ENODEV;
+
+	if (count > ADB_BULK_BUFFER_SIZE)
+		return -EINVAL;
+
+	if (adb_lock(&dev->read_excl))
+		return -EBUSY;
+
+	/* we will block until we're online */
+	while (!(dev->online || dev->error)) {
+		pr_debug("adb_read: waiting for online state\n");
+		ret = wait_event_interruptible(dev->read_wq,
+				(dev->online || dev->error));
+		if (ret < 0) {
+			adb_unlock(&dev->read_excl);
+			return ret;
+		}
+	}
+	if (dev->error) {
+		r = -EIO;
+		goto done;
+	}
+
+requeue_req:
+	/* queue a request */
+	req = dev->rx_req;
+	req->length = count;
+	dev->rx_done = 0;
+	ret = usb_ep_queue(dev->ep_out, req, GFP_ATOMIC);
+	if (ret < 0) {
+		pr_debug("adb_read: failed to queue req %p (%d)\n", req, ret);
+		r = -EIO;
+		dev->error = 1;
+		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) {
+		dev->error = 1;
+		r = ret;
+		usb_ep_dequeue(dev->ep_out, req);
+		goto done;
+	}
+	if (!dev->error) {
+		/* 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;
+		if (copy_to_user(buf, req->buf, xfer))
+			r = -EFAULT;
+
+	} else
+		r = -EIO;
+
+done:
+	adb_unlock(&dev->read_excl);
+	pr_debug("adb_read returning %d\n", r);
+	return r;
+}
+
+static ssize_t adb_write(struct file *fp, const char __user *buf,
+				 size_t count, loff_t *pos)
+{
+	struct adb_dev *dev = fp->private_data;
+	struct usb_request *req = 0;
+	int r = count, xfer;
+	int ret;
+
+	if (!_adb_dev)
+		return -ENODEV;
+	pr_debug("adb_write(%d)\n", count);
+
+	if (adb_lock(&dev->write_excl))
+		return -EBUSY;
+
+	while (count > 0) {
+		if (dev->error) {
+			pr_debug("adb_write dev->error\n");
+			r = -EIO;
+			break;
+		}
+
+		/* get an idle tx request to use */
+		req = 0;
+		ret = wait_event_interruptible(dev->write_wq,
+			(req = adb_req_get(dev, &dev->tx_idle)) || dev->error);
+
+		if (ret < 0) {
+			r = ret;
+			break;
+		}
+
+		if (req != 0) {
+			if (count > ADB_BULK_BUFFER_SIZE)
+				xfer = ADB_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_ATOMIC);
+			if (ret < 0) {
+				pr_debug("adb_write: xfer error %d\n", ret);
+				dev->error = 1;
+				r = -EIO;
+				break;
+			}
+
+			buf += xfer;
+			count -= xfer;
+
+			/* zero this so we don't try to free it on error exit */
+			req = 0;
+		}
+	}
+
+	if (req)
+		adb_req_put(dev, &dev->tx_idle, req);
+
+	adb_unlock(&dev->write_excl);
+	pr_debug("adb_write returning %d\n", r);
+	return r;
+}
+
+static int adb_open(struct inode *ip, struct file *fp)
+{
+	printk(KERN_INFO "adb_open\n");
+	if (!_adb_dev)
+		return -ENODEV;
+
+	if (adb_lock(&_adb_dev->open_excl))
+		return -EBUSY;
+
+	fp->private_data = _adb_dev;
+
+	/* clear the error latch */
+	_adb_dev->error = 0;
+
+	return 0;
+}
+
+static int adb_release(struct inode *ip, struct file *fp)
+{
+	printk(KERN_INFO "adb_release\n");
+	adb_unlock(&_adb_dev->open_excl);
+	return 0;
+}
+
+/* file operations for ADB device /dev/android_adb */
+static struct file_operations adb_fops = {
+	.owner = THIS_MODULE,
+	.read = adb_read,
+	.write = adb_write,
+	.open = adb_open,
+	.release = adb_release,
+};
+
+static struct miscdevice adb_device = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = adb_shortname,
+	.fops = &adb_fops,
+};
+
+
+
+
+static int
+adb_function_bind(struct usb_configuration *c, struct usb_function *f)
+{
+	struct usb_composite_dev *cdev = c->cdev;
+	struct adb_dev	*dev = func_to_adb(f);
+	int			id;
+	int			ret;
+
+	dev->cdev = cdev;
+	DBG(cdev, "adb_function_bind dev: %p\n", dev);
+
+	/* allocate interface ID(s) */
+	id = usb_interface_id(c, f);
+	if (id < 0)
+		return id;
+	adb_interface_desc.bInterfaceNumber = id;
+
+	/* allocate endpoints */
+	ret = adb_create_bulk_endpoints(dev, &adb_fullspeed_in_desc,
+			&adb_fullspeed_out_desc);
+	if (ret)
+		return ret;
+
+	/* support high speed hardware */
+	if (gadget_is_dualspeed(c->cdev->gadget)) {
+		adb_highspeed_in_desc.bEndpointAddress =
+			adb_fullspeed_in_desc.bEndpointAddress;
+		adb_highspeed_out_desc.bEndpointAddress =
+			adb_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
+adb_function_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+	struct adb_dev	*dev = func_to_adb(f);
+	struct usb_request *req;
+
+
+	dev->online = 0;
+	dev->error = 1;
+
+	wake_up(&dev->read_wq);
+
+	adb_request_free(dev->rx_req, dev->ep_out);
+	while ((req = adb_req_get(dev, &dev->tx_idle)))
+		adb_request_free(req, dev->ep_in);
+}
+
+static int adb_function_set_alt(struct usb_function *f,
+		unsigned intf, unsigned alt)
+{
+	struct adb_dev	*dev = func_to_adb(f);
+	struct usb_composite_dev *cdev = f->config->cdev;
+	int ret;
+
+	DBG(cdev, "adb_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 adb_function_disable(struct usb_function *f)
+{
+	struct adb_dev	*dev = func_to_adb(f);
+	struct usb_composite_dev	*cdev = dev->cdev;
+
+	DBG(cdev, "adb_function_disable cdev %p\n", cdev);
+	dev->online = 0;
+	dev->error = 1;
+	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 adb_bind_config(struct usb_configuration *c)
+{
+	struct adb_dev *dev = _adb_dev;
+
+	printk(KERN_INFO "adb_bind_config\n");
+
+	dev->cdev = c->cdev;
+	dev->function.name = "adb";
+	dev->function.fs_descriptors = fs_adb_descs;
+	dev->function.hs_descriptors = hs_adb_descs;
+	dev->function.bind = adb_function_bind;
+	dev->function.unbind = adb_function_unbind;
+	dev->function.set_alt = adb_function_set_alt;
+	dev->function.disable = adb_function_disable;
+
+	return usb_add_function(c, &dev->function);
+}
+
+static int adb_setup(void)
+{
+	struct adb_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);
+	atomic_set(&dev->read_excl, 0);
+	atomic_set(&dev->write_excl, 0);
+
+	INIT_LIST_HEAD(&dev->tx_idle);
+
+	_adb_dev = dev;
+
+	ret = misc_register(&adb_device);
+	if (ret)
+		goto err;
+
+	return 0;
+
+err:
+	kfree(dev);
+	printk(KERN_ERR "adb gadget driver failed to initialize\n");
+	return ret;
+}
+
+static void adb_cleanup(void)
+{
+	misc_deregister(&adb_device);
+
+	kfree(_adb_dev);
+	_adb_dev = NULL;
+}