[mirror_ubuntu-hirsute-kernel.git] / drivers / usb / gadget / f_hid.c

/*
 * f_hid.c -- USB HID function driver
 *
 * Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/kernel.h>
#include <linux/utsname.h>
#include <linux/module.h>
#include <linux/hid.h>
#include <linux/cdev.h>
#include <linux/mutex.h>
#include <linux/poll.h>
#include <linux/uaccess.h>
#include <linux/wait.h>
#include <linux/usb/g_hid.h>

static int major, minors;
static struct class *hidg_class;

/*-------------------------------------------------------------------------*/
/*                            HID gadget struct                            */

struct f_hidg {
	/* configuration */
	unsigned char			bInterfaceSubClass;
	unsigned char			bInterfaceProtocol;
	unsigned short			report_desc_length;
	char				*report_desc;
	unsigned short			report_length;

	/* recv report */
	char				*set_report_buff;
	unsigned short			set_report_length;
	spinlock_t			spinlock;
	wait_queue_head_t		read_queue;

	/* send report */
	struct mutex			lock;
	bool				write_pending;
	wait_queue_head_t		write_queue;
	struct usb_request		*req;

	int				minor;
	struct cdev			cdev;
	struct usb_function		func;
	struct usb_ep			*in_ep;
	struct usb_endpoint_descriptor	*fs_in_ep_desc;
	struct usb_endpoint_descriptor	*hs_in_ep_desc;
};

static inline struct f_hidg *func_to_hidg(struct usb_function *f)
{
	return container_of(f, struct f_hidg, func);
}

/*-------------------------------------------------------------------------*/
/*                           Static descriptors                            */

static struct usb_interface_descriptor hidg_interface_desc = {
	.bLength		= sizeof hidg_interface_desc,
	.bDescriptorType	= USB_DT_INTERFACE,
	/* .bInterfaceNumber	= DYNAMIC */
	.bAlternateSetting	= 0,
	.bNumEndpoints		= 1,
	.bInterfaceClass	= USB_CLASS_HID,
	/* .bInterfaceSubClass	= DYNAMIC */
	/* .bInterfaceProtocol	= DYNAMIC */
	/* .iInterface		= DYNAMIC */
};

static struct hid_descriptor hidg_desc = {
	.bLength			= sizeof hidg_desc,
	.bDescriptorType		= HID_DT_HID,
	.bcdHID				= 0x0101,
	.bCountryCode			= 0x00,
	.bNumDescriptors		= 0x1,
	/*.desc[0].bDescriptorType	= DYNAMIC */
	/*.desc[0].wDescriptorLenght	= DYNAMIC */
};

/* High-Speed Support */

static struct usb_endpoint_descriptor hidg_hs_in_ep_desc = {
	.bLength		= USB_DT_ENDPOINT_SIZE,
	.bDescriptorType	= USB_DT_ENDPOINT,
	.bEndpointAddress	= USB_DIR_IN,
	.bmAttributes		= USB_ENDPOINT_XFER_INT,
	/*.wMaxPacketSize	= DYNAMIC */
	.bInterval		= 4, /* FIXME: Add this field in the
				      * HID gadget configuration?
				      * (struct hidg_func_descriptor)
				      */
};

static struct usb_descriptor_header *hidg_hs_descriptors[] = {
	(struct usb_descriptor_header *)&hidg_interface_desc,
	(struct usb_descriptor_header *)&hidg_desc,
	(struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
	NULL,
};

/* Full-Speed Support */

static struct usb_endpoint_descriptor hidg_fs_in_ep_desc = {
	.bLength		= USB_DT_ENDPOINT_SIZE,
	.bDescriptorType	= USB_DT_ENDPOINT,
	.bEndpointAddress	= USB_DIR_IN,
	.bmAttributes		= USB_ENDPOINT_XFER_INT,
	/*.wMaxPacketSize	= DYNAMIC */
	.bInterval		= 10, /* FIXME: Add this field in the
				       * HID gadget configuration?
				       * (struct hidg_func_descriptor)
				       */
};

static struct usb_descriptor_header *hidg_fs_descriptors[] = {
	(struct usb_descriptor_header *)&hidg_interface_desc,
	(struct usb_descriptor_header *)&hidg_desc,
	(struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
	NULL,
};

/*-------------------------------------------------------------------------*/
/*                              Char Device                                */

static ssize_t f_hidg_read(struct file *file, char __user *buffer,
			size_t count, loff_t *ptr)
{
	struct f_hidg	*hidg     = file->private_data;
	char		*tmp_buff = NULL;
	unsigned long	flags;

	if (!count)
		return 0;

	if (!access_ok(VERIFY_WRITE, buffer, count))
		return -EFAULT;

	spin_lock_irqsave(&hidg->spinlock, flags);

#define READ_COND (hidg->set_report_buff != NULL)

	while (!READ_COND) {
		spin_unlock_irqrestore(&hidg->spinlock, flags);
		if (file->f_flags & O_NONBLOCK)
			return -EAGAIN;

		if (wait_event_interruptible(hidg->read_queue, READ_COND))
			return -ERESTARTSYS;

		spin_lock_irqsave(&hidg->spinlock, flags);
	}


	count = min_t(unsigned, count, hidg->set_report_length);
	tmp_buff = hidg->set_report_buff;
	hidg->set_report_buff = NULL;

	spin_unlock_irqrestore(&hidg->spinlock, flags);

	if (tmp_buff != NULL) {
		/* copy to user outside spinlock */
		count -= copy_to_user(buffer, tmp_buff, count);
		kfree(tmp_buff);
	} else
		count = -ENOMEM;

	return count;
}

static void f_hidg_req_complete(struct usb_ep *ep, struct usb_request *req)
{
	struct f_hidg *hidg = (struct f_hidg *)ep->driver_data;

	if (req->status != 0) {
		ERROR(hidg->func.config->cdev,
			"End Point Request ERROR: %d\n", req->status);
	}

	hidg->write_pending = 0;
	wake_up(&hidg->write_queue);
}

static ssize_t f_hidg_write(struct file *file, const char __user *buffer,
			    size_t count, loff_t *offp)
{
	struct f_hidg *hidg  = file->private_data;
	ssize_t status = -ENOMEM;

	if (!access_ok(VERIFY_READ, buffer, count))
		return -EFAULT;

	mutex_lock(&hidg->lock);

#define WRITE_COND (!hidg->write_pending)

	/* write queue */
	while (!WRITE_COND) {
		mutex_unlock(&hidg->lock);
		if (file->f_flags & O_NONBLOCK)
			return -EAGAIN;

		if (wait_event_interruptible_exclusive(
				hidg->write_queue, WRITE_COND))
			return -ERESTARTSYS;

		mutex_lock(&hidg->lock);
	}

	count  = min_t(unsigned, count, hidg->report_length);
	status = copy_from_user(hidg->req->buf, buffer, count);

	if (status != 0) {
		ERROR(hidg->func.config->cdev,
			"copy_from_user error\n");
		mutex_unlock(&hidg->lock);
		return -EINVAL;
	}

	hidg->req->status   = 0;
	hidg->req->zero     = 0;
	hidg->req->length   = count;
	hidg->req->complete = f_hidg_req_complete;
	hidg->req->context  = hidg;
	hidg->write_pending = 1;

	status = usb_ep_queue(hidg->in_ep, hidg->req, GFP_ATOMIC);
	if (status < 0) {
		ERROR(hidg->func.config->cdev,
			"usb_ep_queue error on int endpoint %zd\n", status);
		hidg->write_pending = 0;
		wake_up(&hidg->write_queue);
	} else {
		status = count;
	}

	mutex_unlock(&hidg->lock);

	return status;
}

static unsigned int f_hidg_poll(struct file *file, poll_table *wait)
{
	struct f_hidg	*hidg  = file->private_data;
	unsigned int	ret = 0;

	poll_wait(file, &hidg->read_queue, wait);
	poll_wait(file, &hidg->write_queue, wait);

	if (WRITE_COND)
		ret |= POLLOUT | POLLWRNORM;

	if (READ_COND)
		ret |= POLLIN | POLLRDNORM;

	return ret;
}

#undef WRITE_COND
#undef READ_COND

static int f_hidg_release(struct inode *inode, struct file *fd)
{
	fd->private_data = NULL;
	return 0;
}

static int f_hidg_open(struct inode *inode, struct file *fd)
{
	struct f_hidg *hidg =
		container_of(inode->i_cdev, struct f_hidg, cdev);

	fd->private_data = hidg;

	return 0;
}

/*-------------------------------------------------------------------------*/
/*                                usb_function                             */

static void hidg_set_report_complete(struct usb_ep *ep, struct usb_request *req)
{
	struct f_hidg *hidg = (struct f_hidg *)req->context;

	if (req->status != 0 || req->buf == NULL || req->actual == 0) {
		ERROR(hidg->func.config->cdev, "%s FAILED\n", __func__);
		return;
	}

	spin_lock(&hidg->spinlock);

	hidg->set_report_buff = krealloc(hidg->set_report_buff,
					 req->actual, GFP_ATOMIC);

	if (hidg->set_report_buff == NULL) {
		spin_unlock(&hidg->spinlock);
		return;
	}
	hidg->set_report_length = req->actual;
	memcpy(hidg->set_report_buff, req->buf, req->actual);

	spin_unlock(&hidg->spinlock);

	wake_up(&hidg->read_queue);
}

static int hidg_setup(struct usb_function *f,
		const struct usb_ctrlrequest *ctrl)
{
	struct f_hidg			*hidg = func_to_hidg(f);
	struct usb_composite_dev	*cdev = f->config->cdev;
	struct usb_request		*req  = cdev->req;
	int status = 0;
	__u16 value, length;

	value	= __le16_to_cpu(ctrl->wValue);
	length	= __le16_to_cpu(ctrl->wLength);

	VDBG(cdev, "hid_setup crtl_request : bRequestType:0x%x bRequest:0x%x "
		"Value:0x%x\n", ctrl->bRequestType, ctrl->bRequest, value);

	switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
		  | HID_REQ_GET_REPORT):
		VDBG(cdev, "get_report\n");

		/* send an empty report */
		length = min_t(unsigned, length, hidg->report_length);
		memset(req->buf, 0x0, length);

		goto respond;
		break;

	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
		  | HID_REQ_GET_PROTOCOL):
		VDBG(cdev, "get_protocol\n");
		goto stall;
		break;

	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
		  | HID_REQ_SET_REPORT):
		VDBG(cdev, "set_report | wLenght=%d\n", ctrl->wLength);
		req->context  = hidg;
		req->complete = hidg_set_report_complete;
		goto respond;
		break;

	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
		  | HID_REQ_SET_PROTOCOL):
		VDBG(cdev, "set_protocol\n");
		goto stall;
		break;

	case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8
		  | USB_REQ_GET_DESCRIPTOR):
		switch (value >> 8) {
		case HID_DT_REPORT:
			VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: REPORT\n");
			length = min_t(unsigned short, length,
						   hidg->report_desc_length);
			memcpy(req->buf, hidg->report_desc, length);
			goto respond;
			break;

		default:
			VDBG(cdev, "Unknown decriptor request 0x%x\n",
				 value >> 8);
			goto stall;
			break;
		}
		break;

	default:
		VDBG(cdev, "Unknown request 0x%x\n",
			 ctrl->bRequest);
		goto stall;
		break;
	}

stall:
	return -EOPNOTSUPP;

respond:
	req->zero = 0;
	req->length = length;
	status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
	if (status < 0)
		ERROR(cdev, "usb_ep_queue error on ep0 %d\n", value);
	return status;
}

static void hidg_disable(struct usb_function *f)
{
	struct f_hidg *hidg = func_to_hidg(f);

	usb_ep_disable(hidg->in_ep);
	hidg->in_ep->driver_data = NULL;
}

static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
{
	struct usb_composite_dev		*cdev = f->config->cdev;
	struct f_hidg				*hidg = func_to_hidg(f);
	int status = 0;

	VDBG(cdev, "hidg_set_alt intf:%d alt:%d\n", intf, alt);

	if (hidg->in_ep != NULL) {
		/* restart endpoint */
		if (hidg->in_ep->driver_data != NULL)
			usb_ep_disable(hidg->in_ep);

		hidg->in_ep->desc = ep_choose(f->config->cdev->gadget,
				hidg->hs_in_ep_desc, hidg->fs_in_ep_desc);
		status = usb_ep_enable(hidg->in_ep);
		if (status < 0) {
			ERROR(cdev, "Enable endpoint FAILED!\n");
			goto fail;
		}
		hidg->in_ep->driver_data = hidg;
	}
fail:
	return status;
}

const struct file_operations f_hidg_fops = {
	.owner		= THIS_MODULE,
	.open		= f_hidg_open,
	.release	= f_hidg_release,
	.write		= f_hidg_write,
	.read		= f_hidg_read,
	.poll		= f_hidg_poll,
	.llseek		= noop_llseek,
};

static int __init hidg_bind(struct usb_configuration *c, struct usb_function *f)
{
	struct usb_ep		*ep;
	struct f_hidg		*hidg = func_to_hidg(f);
	int			status;
	dev_t			dev;

	/* allocate instance-specific interface IDs, and patch descriptors */
	status = usb_interface_id(c, f);
	if (status < 0)
		goto fail;
	hidg_interface_desc.bInterfaceNumber = status;


	/* allocate instance-specific endpoints */
	status = -ENODEV;
	ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_in_ep_desc);
	if (!ep)
		goto fail;
	ep->driver_data = c->cdev;	/* claim */
	hidg->in_ep = ep;

	/* preallocate request and buffer */
	status = -ENOMEM;
	hidg->req = usb_ep_alloc_request(hidg->in_ep, GFP_KERNEL);
	if (!hidg->req)
		goto fail;


	hidg->req->buf = kmalloc(hidg->report_length, GFP_KERNEL);
	if (!hidg->req->buf)
		goto fail;

	/* set descriptor dynamic values */
	hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
	hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
	hidg_hs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
	hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
	hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT;
	hidg_desc.desc[0].wDescriptorLength =
		cpu_to_le16(hidg->report_desc_length);

	hidg->set_report_buff = NULL;

	/* copy descriptors */
	f->descriptors = usb_copy_descriptors(hidg_fs_descriptors);
	if (!f->descriptors)
		goto fail;

	hidg->fs_in_ep_desc = usb_find_endpoint(hidg_fs_descriptors,
						f->descriptors,
						&hidg_fs_in_ep_desc);

	if (gadget_is_dualspeed(c->cdev->gadget)) {
		hidg_hs_in_ep_desc.bEndpointAddress =
			hidg_fs_in_ep_desc.bEndpointAddress;
		f->hs_descriptors = usb_copy_descriptors(hidg_hs_descriptors);
		if (!f->hs_descriptors)
			goto fail;
		hidg->hs_in_ep_desc = usb_find_endpoint(hidg_hs_descriptors,
							f->hs_descriptors,
							&hidg_hs_in_ep_desc);
	} else {
		hidg->hs_in_ep_desc = NULL;
	}

	mutex_init(&hidg->lock);
	spin_lock_init(&hidg->spinlock);
	init_waitqueue_head(&hidg->write_queue);
	init_waitqueue_head(&hidg->read_queue);

	/* create char device */
	cdev_init(&hidg->cdev, &f_hidg_fops);
	dev = MKDEV(major, hidg->minor);
	status = cdev_add(&hidg->cdev, dev, 1);
	if (status)
		goto fail;

	device_create(hidg_class, NULL, dev, NULL, "%s%d", "hidg", hidg->minor);

	return 0;

fail:
	ERROR(f->config->cdev, "hidg_bind FAILED\n");
	if (hidg->req != NULL) {
		kfree(hidg->req->buf);
		if (hidg->in_ep != NULL)
			usb_ep_free_request(hidg->in_ep, hidg->req);
	}

	usb_free_descriptors(f->hs_descriptors);
	usb_free_descriptors(f->descriptors);

	return status;
}

static void hidg_unbind(struct usb_configuration *c, struct usb_function *f)
{
	struct f_hidg *hidg = func_to_hidg(f);

	device_destroy(hidg_class, MKDEV(major, hidg->minor));
	cdev_del(&hidg->cdev);

	/* disable/free request and end point */
	usb_ep_disable(hidg->in_ep);
	usb_ep_dequeue(hidg->in_ep, hidg->req);
	kfree(hidg->req->buf);
	usb_ep_free_request(hidg->in_ep, hidg->req);

	/* free descriptors copies */
	usb_free_descriptors(f->hs_descriptors);
	usb_free_descriptors(f->descriptors);

	kfree(hidg->report_desc);
	kfree(hidg->set_report_buff);
	kfree(hidg);
}

/*-------------------------------------------------------------------------*/
/*                                 Strings                                 */

#define CT_FUNC_HID_IDX	0

static struct usb_string ct_func_string_defs[] = {
	[CT_FUNC_HID_IDX].s	= "HID Interface",
	{},			/* end of list */
};

static struct usb_gadget_strings ct_func_string_table = {
	.language	= 0x0409,	/* en-US */
	.strings	= ct_func_string_defs,
};

static struct usb_gadget_strings *ct_func_strings[] = {
	&ct_func_string_table,
	NULL,
};

/*-------------------------------------------------------------------------*/
/*                             usb_configuration                           */

int __init hidg_bind_config(struct usb_configuration *c,
			    struct hidg_func_descriptor *fdesc, int index)
{
	struct f_hidg *hidg;
	int status;

	if (index >= minors)
		return -ENOENT;

	/* maybe allocate device-global string IDs, and patch descriptors */
	if (ct_func_string_defs[CT_FUNC_HID_IDX].id == 0) {
		status = usb_string_id(c->cdev);
		if (status < 0)
			return status;
		ct_func_string_defs[CT_FUNC_HID_IDX].id = status;
		hidg_interface_desc.iInterface = status;
	}

	/* allocate and initialize one new instance */
	hidg = kzalloc(sizeof *hidg, GFP_KERNEL);
	if (!hidg)
		return -ENOMEM;

	hidg->minor = index;
	hidg->bInterfaceSubClass = fdesc->subclass;
	hidg->bInterfaceProtocol = fdesc->protocol;
	hidg->report_length = fdesc->report_length;
	hidg->report_desc_length = fdesc->report_desc_length;
	hidg->report_desc = kmemdup(fdesc->report_desc,
				    fdesc->report_desc_length,
				    GFP_KERNEL);
	if (!hidg->report_desc) {
		kfree(hidg);
		return -ENOMEM;
	}

	hidg->func.name    = "hid";
	hidg->func.strings = ct_func_strings;
	hidg->func.bind    = hidg_bind;
	hidg->func.unbind  = hidg_unbind;
	hidg->func.set_alt = hidg_set_alt;
	hidg->func.disable = hidg_disable;
	hidg->func.setup   = hidg_setup;

	status = usb_add_function(c, &hidg->func);
	if (status)
		kfree(hidg);

	return status;
}

int __init ghid_setup(struct usb_gadget *g, int count)
{
	int status;
	dev_t dev;

	hidg_class = class_create(THIS_MODULE, "hidg");

	status = alloc_chrdev_region(&dev, 0, count, "hidg");
	if (!status) {
		major = MAJOR(dev);
		minors = count;
	}

	return status;
}

void ghid_cleanup(void)
{
	if (major) {
		unregister_chrdev_region(MKDEV(major, 0), minors);
		major = minors = 0;
	}

	class_destroy(hidg_class);
	hidg_class = NULL;
}
Commit	Line	Data
71adf118 FC	1	/*
	2	* f_hid.c -- USB HID function driver
	3	*
	4	* Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	*/
	20
	21	#include <linux/kernel.h>
	22	#include <linux/utsname.h>
	23	#include <linux/module.h>
	24	#include <linux/hid.h>
	25	#include <linux/cdev.h>
	26	#include <linux/mutex.h>
	27	#include <linux/poll.h>
71adf118 FC	28	#include <linux/uaccess.h>
	29	#include <linux/wait.h>
	30	#include <linux/usb/g_hid.h>
	31
	32	static int major, minors;
	33	static struct class *hidg_class;
	34
	35	/-------------------------------------------------------------------------/
	36	/* HID gadget struct */
	37
	38	struct f_hidg {
	39	/* configuration */
	40	unsigned char bInterfaceSubClass;
	41	unsigned char bInterfaceProtocol;
	42	unsigned short report_desc_length;
	43	char *report_desc;
	44	unsigned short report_length;
	45
	46	/* recv report */
	47	char *set_report_buff;
	48	unsigned short set_report_length;
	49	spinlock_t spinlock;
	50	wait_queue_head_t read_queue;
	51
	52	/* send report */
	53	struct mutex lock;
	54	bool write_pending;
	55	wait_queue_head_t write_queue;
	56	struct usb_request *req;
	57
	58	int minor;
	59	struct cdev cdev;
	60	struct usb_function func;
	61	struct usb_ep *in_ep;
	62	struct usb_endpoint_descriptor *fs_in_ep_desc;
	63	struct usb_endpoint_descriptor *hs_in_ep_desc;
	64	};
	65
	66	static inline struct f_hidg func_to_hidg(struct usb_function f)
	67	{
	68	return container_of(f, struct f_hidg, func);
	69	}
	70
	71	/-------------------------------------------------------------------------/
	72	/* Static descriptors */
	73
	74	static struct usb_interface_descriptor hidg_interface_desc = {
	75	.bLength = sizeof hidg_interface_desc,
	76	.bDescriptorType = USB_DT_INTERFACE,
	77	/* .bInterfaceNumber = DYNAMIC */
	78	.bAlternateSetting = 0,
	79	.bNumEndpoints = 1,
	80	.bInterfaceClass = USB_CLASS_HID,
	81	/* .bInterfaceSubClass = DYNAMIC */
	82	/* .bInterfaceProtocol = DYNAMIC */
	83	/* .iInterface = DYNAMIC */
	84	};
	85
	86	static struct hid_descriptor hidg_desc = {
	87	.bLength = sizeof hidg_desc,
	88	.bDescriptorType = HID_DT_HID,
	89	.bcdHID = 0x0101,
	90	.bCountryCode = 0x00,
	91	.bNumDescriptors = 0x1,
92	/.desc[0].bDescriptorType = DYNAMIC /
93	/.desc[0].wDescriptorLenght = DYNAMIC /
94	};
95
96	/* High-Speed Support */
97
98	static struct usb_endpoint_descriptor hidg_hs_in_ep_desc = {
99	.bLength = USB_DT_ENDPOINT_SIZE,
100	.bDescriptorType = USB_DT_ENDPOINT,
101	.bEndpointAddress = USB_DIR_IN,
102	.bmAttributes = USB_ENDPOINT_XFER_INT,
103	/.wMaxPacketSize = DYNAMIC /
104	.bInterval = 4, /* FIXME: Add this field in the
105	* HID gadget configuration?
106	* (struct hidg_func_descriptor)
107	*/
108	};
109
110	static struct usb_descriptor_header *hidg_hs_descriptors[] = {
111	(struct usb_descriptor_header *)&hidg_interface_desc,
112	(struct usb_descriptor_header *)&hidg_desc,
113	(struct usb_descriptor_header *)&hidg_hs_in_ep_desc,
114	NULL,
115	};
116
117	/* Full-Speed Support */
118
119	static struct usb_endpoint_descriptor hidg_fs_in_ep_desc = {
120	.bLength = USB_DT_ENDPOINT_SIZE,
121	.bDescriptorType = USB_DT_ENDPOINT,
122	.bEndpointAddress = USB_DIR_IN,
123	.bmAttributes = USB_ENDPOINT_XFER_INT,
124	/.wMaxPacketSize = DYNAMIC /
125	.bInterval = 10, /* FIXME: Add this field in the
126	* HID gadget configuration?
127	* (struct hidg_func_descriptor)
128	*/
129	};
130
131	static struct usb_descriptor_header *hidg_fs_descriptors[] = {
132	(struct usb_descriptor_header *)&hidg_interface_desc,
133	(struct usb_descriptor_header *)&hidg_desc,
134	(struct usb_descriptor_header *)&hidg_fs_in_ep_desc,
135	NULL,
136	};
137
138	/-------------------------------------------------------------------------/
139	/* Char Device */
140
141	static ssize_t f_hidg_read(struct file file, char __user buffer,
142	size_t count, loff_t *ptr)
143	{
fd63b10b	144	struct f_hidg *hidg = file->private_data;
71adf118 FC	145	char *tmp_buff = NULL;
	146	unsigned long flags;
	147
	148	if (!count)
	149	return 0;
	150
	151	if (!access_ok(VERIFY_WRITE, buffer, count))
	152	return -EFAULT;
	153
	154	spin_lock_irqsave(&hidg->spinlock, flags);
	155
	156	#define READ_COND (hidg->set_report_buff != NULL)
	157
	158	while (!READ_COND) {
	159	spin_unlock_irqrestore(&hidg->spinlock, flags);
	160	if (file->f_flags & O_NONBLOCK)
	161	return -EAGAIN;
	162
	163	if (wait_event_interruptible(hidg->read_queue, READ_COND))
	164	return -ERESTARTSYS;
	165
	166	spin_lock_irqsave(&hidg->spinlock, flags);
	167	}
	168
	169
	170	count = min_t(unsigned, count, hidg->set_report_length);
	171	tmp_buff = hidg->set_report_buff;
	172	hidg->set_report_buff = NULL;
	173
	174	spin_unlock_irqrestore(&hidg->spinlock, flags);
	175
	176	if (tmp_buff != NULL) {
	177	/* copy to user outside spinlock */
	178	count -= copy_to_user(buffer, tmp_buff, count);
	179	kfree(tmp_buff);
	180	} else
	181	count = -ENOMEM;
	182
	183	return count;
	184	}
	185
	186	static void f_hidg_req_complete(struct usb_ep ep, struct usb_request req)
	187	{
	188	struct f_hidg hidg = (struct f_hidg )ep->driver_data;
	189
	190	if (req->status != 0) {
	191	ERROR(hidg->func.config->cdev,
	192	"End Point Request ERROR: %d\n", req->status);
	193	}
	194
	195	hidg->write_pending = 0;
	196	wake_up(&hidg->write_queue);
	197	}
	198
	199	static ssize_t f_hidg_write(struct file file, const char __user buffer,
	200	size_t count, loff_t *offp)
	201	{
fd63b10b	202	struct f_hidg *hidg = file->private_data;
71adf118 FC	203	ssize_t status = -ENOMEM;
	204
	205	if (!access_ok(VERIFY_READ, buffer, count))
	206	return -EFAULT;
	207
	208	mutex_lock(&hidg->lock);
	209
	210	#define WRITE_COND (!hidg->write_pending)
	211
	212	/* write queue */
	213	while (!WRITE_COND) {
	214	mutex_unlock(&hidg->lock);
	215	if (file->f_flags & O_NONBLOCK)
	216	return -EAGAIN;
	217
	218	if (wait_event_interruptible_exclusive(
	219	hidg->write_queue, WRITE_COND))
	220	return -ERESTARTSYS;
	221
	222	mutex_lock(&hidg->lock);
	223	}
	224
	225	count = min_t(unsigned, count, hidg->report_length);
	226	status = copy_from_user(hidg->req->buf, buffer, count);
	227
	228	if (status != 0) {
	229	ERROR(hidg->func.config->cdev,
	230	"copy_from_user error\n");
	231	mutex_unlock(&hidg->lock);
	232	return -EINVAL;
	233	}
	234
	235	hidg->req->status = 0;
	236	hidg->req->zero = 0;
	237	hidg->req->length = count;
	238	hidg->req->complete = f_hidg_req_complete;
	239	hidg->req->context = hidg;
	240	hidg->write_pending = 1;
	241
	242	status = usb_ep_queue(hidg->in_ep, hidg->req, GFP_ATOMIC);
	243	if (status < 0) {
	244	ERROR(hidg->func.config->cdev,
	245	"usb_ep_queue error on int endpoint %zd\n", status);
	246	hidg->write_pending = 0;
	247	wake_up(&hidg->write_queue);
	248	} else {
	249	status = count;
	250	}
	251
	252	mutex_unlock(&hidg->lock);
	253
	254	return status;
	255	}
	256
	257	static unsigned int f_hidg_poll(struct file file, poll_table wait)
	258	{
fd63b10b	259	struct f_hidg *hidg = file->private_data;
71adf118 FC	260	unsigned int ret = 0;
	261
	262	poll_wait(file, &hidg->read_queue, wait);
	263	poll_wait(file, &hidg->write_queue, wait);
	264
	265	if (WRITE_COND)
	266	ret \|= POLLOUT \| POLLWRNORM;
	267
	268	if (READ_COND)
	269	ret \|= POLLIN \| POLLRDNORM;
	270
	271	return ret;
	272	}
	273
	274	#undef WRITE_COND
	275	#undef READ_COND
	276
	277	static int f_hidg_release(struct inode inode, struct file fd)
	278	{
	279	fd->private_data = NULL;
	280	return 0;
	281	}
	282
	283	static int f_hidg_open(struct inode inode, struct file fd)
	284	{
	285	struct f_hidg *hidg =
	286	container_of(inode->i_cdev, struct f_hidg, cdev);
	287
	288	fd->private_data = hidg;
	289
	290	return 0;
	291	}
	292
	293	/-------------------------------------------------------------------------/
	294	/* usb_function */
	295
	296	static void hidg_set_report_complete(struct usb_ep ep, struct usb_request req)
	297	{
	298	struct f_hidg hidg = (struct f_hidg )req->context;
	299
	300	if (req->status != 0 \|\| req->buf == NULL \|\| req->actual == 0) {
	301	ERROR(hidg->func.config->cdev, "%s FAILED\n", __func__);
	302	return;
	303	}
	304
	305	spin_lock(&hidg->spinlock);
	306
	307	hidg->set_report_buff = krealloc(hidg->set_report_buff,
	308	req->actual, GFP_ATOMIC);
	309
	310	if (hidg->set_report_buff == NULL) {
	311	spin_unlock(&hidg->spinlock);
	312	return;
	313	}
	314	hidg->set_report_length = req->actual;
	315	memcpy(hidg->set_report_buff, req->buf, req->actual);
	316
	317	spin_unlock(&hidg->spinlock);
	318
	319	wake_up(&hidg->read_queue);
71adf118 FC	320	}
	321
	322	static int hidg_setup(struct usb_function *f,
	323	const struct usb_ctrlrequest *ctrl)
	324	{
	325	struct f_hidg *hidg = func_to_hidg(f);
	326	struct usb_composite_dev *cdev = f->config->cdev;
	327	struct usb_request *req = cdev->req;
	328	int status = 0;
	329	__u16 value, length;
	330
	331	value = __le16_to_cpu(ctrl->wValue);
	332	length = __le16_to_cpu(ctrl->wLength);
	333
	334	VDBG(cdev, "hid_setup crtl_request : bRequestType:0x%x bRequest:0x%x "
	335	"Value:0x%x\n", ctrl->bRequestType, ctrl->bRequest, value);
	336
	337	switch ((ctrl->bRequestType << 8) \| ctrl->bRequest) {
	338	case ((USB_DIR_IN \| USB_TYPE_CLASS \| USB_RECIP_INTERFACE) << 8
	339	\| HID_REQ_GET_REPORT):
	340	VDBG(cdev, "get_report\n");
	341
	342	/* send an empty report */
	343	length = min_t(unsigned, length, hidg->report_length);
	344	memset(req->buf, 0x0, length);
	345
	346	goto respond;
	347	break;
	348
	349	case ((USB_DIR_IN \| USB_TYPE_CLASS \| USB_RECIP_INTERFACE) << 8
	350	\| HID_REQ_GET_PROTOCOL):
	351	VDBG(cdev, "get_protocol\n");
	352	goto stall;
	353	break;
	354
	355	case ((USB_DIR_OUT \| USB_TYPE_CLASS \| USB_RECIP_INTERFACE) << 8
	356	\| HID_REQ_SET_REPORT):
	357	VDBG(cdev, "set_report \| wLenght=%d\n", ctrl->wLength);
	358	req->context = hidg;
	359	req->complete = hidg_set_report_complete;
	360	goto respond;
	361	break;
	362
	363	case ((USB_DIR_OUT \| USB_TYPE_CLASS \| USB_RECIP_INTERFACE) << 8
	364	\| HID_REQ_SET_PROTOCOL):
	365	VDBG(cdev, "set_protocol\n");
	366	goto stall;
	367	break;
	368
	369	case ((USB_DIR_IN \| USB_TYPE_STANDARD \| USB_RECIP_INTERFACE) << 8
	370	\| USB_REQ_GET_DESCRIPTOR):
	371	switch (value >> 8) {
	372	case HID_DT_REPORT:
	373	VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: REPORT\n");
	374	length = min_t(unsigned short, length,
	375	hidg->report_desc_length);
	376	memcpy(req->buf, hidg->report_desc, length);
	377	goto respond;
	378	break;
	379
	380	default:
	381	VDBG(cdev, "Unknown decriptor request 0x%x\n",
	382	value >> 8);
	383	goto stall;
384	break;
385	}
386	break;
387
388	default:
389	VDBG(cdev, "Unknown request 0x%x\n",
390	ctrl->bRequest);
391	goto stall;
392	break;
393	}
394
395	stall:
396	return -EOPNOTSUPP;
397
398	respond:
399	req->zero = 0;
400	req->length = length;
401	status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
402	if (status < 0)
403	ERROR(cdev, "usb_ep_queue error on ep0 %d\n", value);
404	return status;
405	}
406
407	static void hidg_disable(struct usb_function *f)
408	{
409	struct f_hidg *hidg = func_to_hidg(f);
410
411	usb_ep_disable(hidg->in_ep);
412	hidg->in_ep->driver_data = NULL;
71adf118 FC	413	}
	414
	415	static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
	416	{
	417	struct usb_composite_dev *cdev = f->config->cdev;
	418	struct f_hidg *hidg = func_to_hidg(f);
71adf118 FC	419	int status = 0;
	420
	421	VDBG(cdev, "hidg_set_alt intf:%d alt:%d\n", intf, alt);
	422
	423	if (hidg->in_ep != NULL) {
	424	/* restart endpoint */
	425	if (hidg->in_ep->driver_data != NULL)
	426	usb_ep_disable(hidg->in_ep);
	427
72c973dd	428	hidg->in_ep->desc = ep_choose(f->config->cdev->gadget,
71adf118	429	hidg->hs_in_ep_desc, hidg->fs_in_ep_desc);
72c973dd	430	status = usb_ep_enable(hidg->in_ep);
71adf118 FC	431	if (status < 0) {
	432	ERROR(cdev, "Enable endpoint FAILED!\n");
	433	goto fail;
	434	}
	435	hidg->in_ep->driver_data = hidg;
	436	}
	437	fail:
	438	return status;
	439	}
	440
	441	const struct file_operations f_hidg_fops = {
	442	.owner = THIS_MODULE,
	443	.open = f_hidg_open,
	444	.release = f_hidg_release,
	445	.write = f_hidg_write,
	446	.read = f_hidg_read,
	447	.poll = f_hidg_poll,
6038f373	448	.llseek = noop_llseek,
71adf118 FC	449	};
	450
	451	static int __init hidg_bind(struct usb_configuration c, struct usb_function f)
	452	{
	453	struct usb_ep *ep;
	454	struct f_hidg *hidg = func_to_hidg(f);
	455	int status;
	456	dev_t dev;
	457
	458	/* allocate instance-specific interface IDs, and patch descriptors */
	459	status = usb_interface_id(c, f);
	460	if (status < 0)
	461	goto fail;
	462	hidg_interface_desc.bInterfaceNumber = status;
	463
	464
	465	/* allocate instance-specific endpoints */
	466	status = -ENODEV;
	467	ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_in_ep_desc);
	468	if (!ep)
	469	goto fail;
	470	ep->driver_data = c->cdev; /* claim */
	471	hidg->in_ep = ep;
	472
	473	/* preallocate request and buffer */
	474	status = -ENOMEM;
	475	hidg->req = usb_ep_alloc_request(hidg->in_ep, GFP_KERNEL);
	476	if (!hidg->req)
	477	goto fail;
	478
	479
	480	hidg->req->buf = kmalloc(hidg->report_length, GFP_KERNEL);
	481	if (!hidg->req->buf)
	482	goto fail;
	483
	484	/* set descriptor dynamic values */
	485	hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
	486	hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
	487	hidg_hs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
	488	hidg_fs_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
	489	hidg_desc.desc[0].bDescriptorType = HID_DT_REPORT;
	490	hidg_desc.desc[0].wDescriptorLength =
	491	cpu_to_le16(hidg->report_desc_length);
	492
	493	hidg->set_report_buff = NULL;
	494
	495	/* copy descriptors */
	496	f->descriptors = usb_copy_descriptors(hidg_fs_descriptors);
	497	if (!f->descriptors)
	498	goto fail;
	499
	500	hidg->fs_in_ep_desc = usb_find_endpoint(hidg_fs_descriptors,
	501	f->descriptors,
	502	&hidg_fs_in_ep_desc);
	503
	504	if (gadget_is_dualspeed(c->cdev->gadget)) {
	505	hidg_hs_in_ep_desc.bEndpointAddress =
	506	hidg_fs_in_ep_desc.bEndpointAddress;
	507	f->hs_descriptors = usb_copy_descriptors(hidg_hs_descriptors);
	508	if (!f->hs_descriptors)
	509	goto fail;
	510	hidg->hs_in_ep_desc = usb_find_endpoint(hidg_hs_descriptors,
	511	f->hs_descriptors,
	512	&hidg_hs_in_ep_desc);
513	} else {
514	hidg->hs_in_ep_desc = NULL;
515	}
516
517	mutex_init(&hidg->lock);
518	spin_lock_init(&hidg->spinlock);
519	init_waitqueue_head(&hidg->write_queue);
520	init_waitqueue_head(&hidg->read_queue);
521
522	/* create char device */
523	cdev_init(&hidg->cdev, &f_hidg_fops);
524	dev = MKDEV(major, hidg->minor);
525	status = cdev_add(&hidg->cdev, dev, 1);
526	if (status)
527	goto fail;
528
529	device_create(hidg_class, NULL, dev, NULL, "%s%d", "hidg", hidg->minor);
530
531	return 0;
532
533	fail:
534	ERROR(f->config->cdev, "hidg_bind FAILED\n");
535	if (hidg->req != NULL) {
536	kfree(hidg->req->buf);
537	if (hidg->in_ep != NULL)
538	usb_ep_free_request(hidg->in_ep, hidg->req);
539	}
540
541	usb_free_descriptors(f->hs_descriptors);
542	usb_free_descriptors(f->descriptors);
543
544	return status;
545	}
546
547	static void hidg_unbind(struct usb_configuration c, struct usb_function f)
548	{
549	struct f_hidg *hidg = func_to_hidg(f);
550
551	device_destroy(hidg_class, MKDEV(major, hidg->minor));
552	cdev_del(&hidg->cdev);
553
554	/* disable/free request and end point */
555	usb_ep_disable(hidg->in_ep);
556	usb_ep_dequeue(hidg->in_ep, hidg->req);
557	kfree(hidg->req->buf);
558	usb_ep_free_request(hidg->in_ep, hidg->req);
559
560	/* free descriptors copies */
561	usb_free_descriptors(f->hs_descriptors);
562	usb_free_descriptors(f->descriptors);
563
564	kfree(hidg->report_desc);
565	kfree(hidg->set_report_buff);
566	kfree(hidg);
567	}
568
569	/-------------------------------------------------------------------------/
570	/* Strings */
571
572	#define CT_FUNC_HID_IDX 0
573
574	static struct usb_string ct_func_string_defs[] = {
575	[CT_FUNC_HID_IDX].s = "HID Interface",
576	{}, /* end of list */
577	};
578
579	static struct usb_gadget_strings ct_func_string_table = {
580	.language = 0x0409, /* en-US */
581	.strings = ct_func_string_defs,
582	};
583
584	static struct usb_gadget_strings *ct_func_strings[] = {
585	&ct_func_string_table,
586	NULL,
587	};
588
589	/-------------------------------------------------------------------------/
590	/* usb_configuration */
591
592	int __init hidg_bind_config(struct usb_configuration *c,
593	struct hidg_func_descriptor *fdesc, int index)
594	{
595	struct f_hidg *hidg;
596	int status;
597
598	if (index >= minors)
599	return -ENOENT;
600
601	/* maybe allocate device-global string IDs, and patch descriptors */
602	if (ct_func_string_defs[CT_FUNC_HID_IDX].id == 0) {
603	status = usb_string_id(c->cdev);
604	if (status < 0)
605	return status;
606	ct_func_string_defs[CT_FUNC_HID_IDX].id = status;
607	hidg_interface_desc.iInterface = status;
608	}
609
610	/* allocate and initialize one new instance */
611	hidg = kzalloc(sizeof *hidg, GFP_KERNEL);
612	if (!hidg)
613	return -ENOMEM;
614
615	hidg->minor = index;
616	hidg->bInterfaceSubClass = fdesc->subclass;
617	hidg->bInterfaceProtocol = fdesc->protocol;
618	hidg->report_length = fdesc->report_length;
619	hidg->report_desc_length = fdesc->report_desc_length;
620	hidg->report_desc = kmemdup(fdesc->report_desc,
621	fdesc->report_desc_length,
622	GFP_KERNEL);
623	if (!hidg->report_desc) {
624	kfree(hidg);
625	return -ENOMEM;
626	}
627
628	hidg->func.name = "hid";
629	hidg->func.strings = ct_func_strings;
630	hidg->func.bind = hidg_bind;
631	hidg->func.unbind = hidg_unbind;
632	hidg->func.set_alt = hidg_set_alt;
633	hidg->func.disable = hidg_disable;
634	hidg->func.setup = hidg_setup;
635
636	status = usb_add_function(c, &hidg->func);
637	if (status)
638	kfree(hidg);
639
640	return status;
641	}
642
643	int __init ghid_setup(struct usb_gadget *g, int count)
644	{
645	int status;
646	dev_t dev;
647
648	hidg_class = class_create(THIS_MODULE, "hidg");
649
650	status = alloc_chrdev_region(&dev, 0, count, "hidg");
651	if (!status) {
652	major = MAJOR(dev);
653	minors = count;
654	}
655
656	return status;
657	}
658
659	void ghid_cleanup(void)
660	{
661	if (major) {
662	unregister_chrdev_region(MKDEV(major, 0), minors);
663	major = minors = 0;
664	}
665
666	class_destroy(hidg_class);
667	hidg_class = NULL;
668	}