drivers/media/usb/stk1160/stk1160-core.c - linux - Git at Google

 /*
  * STK1160 driver
  *
  * Copyright (C) 2012 Ezequiel Garcia
  * <elezegarcia--a.t--gmail.com>
  *
  * Based on Easycap driver by R.M. Thomas
  *	Copyright (C) 2010 R.M. Thomas
  *	<rmthomas--a.t--sciolus.org>
  *
  * 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.
  *
  * TODO:
  *
  * 1. (Try to) detect if we must register ac97 mixer
  * 2. Support stream at lower speed: lower frame rate or lower frame size.
  *
  */

 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/slab.h>

 #include <linux/usb.h>
 #include <linux/mm.h>
 #include <linux/vmalloc.h>
 #include <media/saa7115.h>

 #include "stk1160.h"
 #include "stk1160-reg.h"

 static unsigned int input;
 module_param(input, int, 0644);
 MODULE_PARM_DESC(input, "Set default input");

 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Ezequiel Garcia");
 MODULE_DESCRIPTION("STK1160 driver");

 /* Devices supported by this driver */
 static struct usb_device_id stk1160_id_table[] = {
 	{ USB_DEVICE(0x05e1, 0x0408) },
 	{ }
 };
 MODULE_DEVICE_TABLE(usb, stk1160_id_table);

 /* saa7113 I2C address */
 static unsigned short saa7113_addrs[] = {
 	0x4a >> 1,
 	I2C_CLIENT_END
 };

 /*
  * Read/Write stk registers
  */
 int stk1160_read_reg(struct stk1160 *dev, u16 reg, u8 *value)
 {
 	int ret;
 	int pipe = usb_rcvctrlpipe(dev->udev, 0);
 	u8 *buf;

 	*value = 0;

 	buf = kmalloc(sizeof(u8), GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;
 	ret = usb_control_msg(dev->udev, pipe, 0x00,
 			USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 			0x00, reg, buf, sizeof(u8), HZ);
 	if (ret < 0) {
 		stk1160_err("read failed on reg 0x%x (%d)\n",
 			reg, ret);
 		kfree(buf);
 		return ret;
 	}

 	*value = *buf;
 	kfree(buf);
 	return 0;
 }

 int stk1160_write_reg(struct stk1160 *dev, u16 reg, u16 value)
 {
 	int ret;
 	int pipe = usb_sndctrlpipe(dev->udev, 0);

 	ret =  usb_control_msg(dev->udev, pipe, 0x01,
 			USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 			value, reg, NULL, 0, HZ);
 	if (ret < 0) {
 		stk1160_err("write failed on reg 0x%x (%d)\n",
 			reg, ret);
 		return ret;
 	}

 	return 0;
 }

 void stk1160_select_input(struct stk1160 *dev)
 {
 	int route;
 	static const u8 gctrl[] = {
 		0x98, 0x90, 0x88, 0x80, 0x98
 	};

 	if (dev->ctl_input == STK1160_SVIDEO_INPUT)
 		route = SAA7115_SVIDEO3;
 	else
 		route = SAA7115_COMPOSITE0;

 	if (dev->ctl_input < ARRAY_SIZE(gctrl)) {
 		v4l2_device_call_all(&dev->v4l2_dev, 0, video, s_routing,
 				route, 0, 0);
 		stk1160_write_reg(dev, STK1160_GCTRL, gctrl[dev->ctl_input]);
 	}
 }

 /* TODO: We should break this into pieces */
 static void stk1160_reg_reset(struct stk1160 *dev)
 {
 	int i;

 	static const struct regval ctl[] = {
 		{STK1160_GCTRL+2, 0x0078},

 		{STK1160_RMCTL+1, 0x0000},
 		{STK1160_RMCTL+3, 0x0002},

 		{STK1160_PLLSO,   0x0010},
 		{STK1160_PLLSO+1, 0x0000},
 		{STK1160_PLLSO+2, 0x0014},
 		{STK1160_PLLSO+3, 0x000E},

 		{STK1160_PLLFD,   0x0046},

 		/* Timing generator setup */
 		{STK1160_TIGEN,   0x0012},
 		{STK1160_TICTL,   0x002D},
 		{STK1160_TICTL+1, 0x0001},
 		{STK1160_TICTL+2, 0x0000},
 		{STK1160_TICTL+3, 0x0000},
 		{STK1160_TIGEN,   0x0080},

 		{0xffff, 0xffff}
 	};

 	for (i = 0; ctl[i].reg != 0xffff; i++)
 		stk1160_write_reg(dev, ctl[i].reg, ctl[i].val);
 }

 static void stk1160_release(struct v4l2_device *v4l2_dev)
 {
 	struct stk1160 *dev = container_of(v4l2_dev, struct stk1160, v4l2_dev);

 	stk1160_dbg("releasing all resources\n");

 	stk1160_i2c_unregister(dev);

 	v4l2_ctrl_handler_free(&dev->ctrl_handler);
 	v4l2_device_unregister(&dev->v4l2_dev);
 	kfree(dev->alt_max_pkt_size);
 	kfree(dev);
 }

 /* high bandwidth multiplier, as encoded in highspeed endpoint descriptors */
 #define hb_mult(wMaxPacketSize) (1 + (((wMaxPacketSize) >> 11) & 0x03))

 /*
  * Scan usb interface and populate max_pkt_size array
  * with information on each alternate setting.
  * The array should be allocated by the caller.
  */
 static int stk1160_scan_usb(struct usb_interface *intf, struct usb_device *udev,
 		unsigned int *max_pkt_size)
 {
 	int i, e, sizedescr, size, ifnum;
 	const struct usb_endpoint_descriptor *desc;

 	bool has_video = false, has_audio = false;
 	const char *speed;

 	ifnum = intf->altsetting[0].desc.bInterfaceNumber;

 	/* Get endpoints */
 	for (i = 0; i < intf->num_altsetting; i++) {

 		for (e = 0; e < intf->altsetting[i].desc.bNumEndpoints; e++) {

 			/* This isn't clear enough, at least to me */
 			desc = &intf->altsetting[i].endpoint[e].desc;
 			sizedescr = le16_to_cpu(desc->wMaxPacketSize);
 			size = sizedescr & 0x7ff;

 			if (udev->speed == USB_SPEED_HIGH)
 				size = size * hb_mult(sizedescr);

 			if (usb_endpoint_xfer_isoc(desc) &&
 			    usb_endpoint_dir_in(desc)) {
 				switch (desc->bEndpointAddress) {
 				case STK1160_EP_AUDIO:
 					has_audio = true;
 					break;
 				case STK1160_EP_VIDEO:
 					has_video = true;
 					max_pkt_size[i] = size;
 					break;
 				}
 			}
 		}
 	}

 	/* Is this even possible? */
 	if (!(has_audio || has_video)) {
 		dev_err(&udev->dev, "no audio or video endpoints found\n");
 		return -ENODEV;
 	}

 	switch (udev->speed) {
 	case USB_SPEED_LOW:
 		speed = "1.5";
 		break;
 	case USB_SPEED_FULL:
 		speed = "12";
 		break;
 	case USB_SPEED_HIGH:
 		speed = "480";
 		break;
 	default:
 		speed = "unknown";
 	}

 	dev_info(&udev->dev, "New device %s %s @ %s Mbps (%04x:%04x, interface %d, class %d)\n",
 		udev->manufacturer ? udev->manufacturer : "",
 		udev->product ? udev->product : "",
 		speed,
 		le16_to_cpu(udev->descriptor.idVendor),
 		le16_to_cpu(udev->descriptor.idProduct),
 		ifnum,
 		intf->altsetting->desc.bInterfaceNumber);

 	/* This should never happen, since we rejected audio interfaces */
 	if (has_audio)
 		dev_warn(&udev->dev, "audio interface %d found.\n\
 				This is not implemented by this driver,\
 				you should use snd-usb-audio instead\n", ifnum);

 	if (has_video)
 		dev_info(&udev->dev, "video interface %d found\n",
 				ifnum);

 	/*
 	 * Make sure we have 480 Mbps of bandwidth, otherwise things like
 	 * video stream wouldn't likely work, since 12 Mbps is generally
 	 * not enough even for most streams.
 	 */
 	if (udev->speed != USB_SPEED_HIGH)
 		dev_warn(&udev->dev, "must be connected to a high-speed USB 2.0 port\n\
 				You may not be able to stream video smoothly\n");

 	return 0;
 }

 static int stk1160_probe(struct usb_interface *interface,
 		const struct usb_device_id *id)
 {
 	int rc = 0;

 	unsigned int *alt_max_pkt_size;	/* array of wMaxPacketSize */
 	struct usb_device *udev;
 	struct stk1160 *dev;

 	udev = interface_to_usbdev(interface);

 	/*
 	 * Since usb audio class is supported by snd-usb-audio,
 	 * we reject audio interface.
 	 */
 	if (interface->altsetting[0].desc.bInterfaceClass == USB_CLASS_AUDIO)
 		return -ENODEV;

 	/* Alloc an array for all possible max_pkt_size */
 	alt_max_pkt_size = kmalloc(sizeof(alt_max_pkt_size[0]) *
 			interface->num_altsetting, GFP_KERNEL);
 	if (alt_max_pkt_size == NULL)
 		return -ENOMEM;

 	/*
 	 * Scan usb posibilities and populate alt_max_pkt_size array.
 	 * Also, check if device speed is fast enough.
 	 */
 	rc = stk1160_scan_usb(interface, udev, alt_max_pkt_size);
 	if (rc < 0) {
 		kfree(alt_max_pkt_size);
 		return rc;
 	}

 	dev = kzalloc(sizeof(struct stk1160), GFP_KERNEL);
 	if (dev == NULL) {
 		kfree(alt_max_pkt_size);
 		return -ENOMEM;
 	}

 	dev->alt_max_pkt_size = alt_max_pkt_size;
 	dev->udev = udev;
 	dev->num_alt = interface->num_altsetting;
 	dev->ctl_input = input;

 	/* We save struct device for debug purposes only */
 	dev->dev = &interface->dev;

 	usb_set_intfdata(interface, dev);

 	/* initialize videobuf2 stuff */
 	rc = stk1160_vb2_setup(dev);
 	if (rc < 0)
 		goto free_err;

 	/*
 	 * There is no need to take any locks here in probe
 	 * because we register the device node as the *last* thing.
 	 */
 	spin_lock_init(&dev->buf_lock);
 	mutex_init(&dev->v4l_lock);
 	mutex_init(&dev->vb_queue_lock);

 	rc = v4l2_ctrl_handler_init(&dev->ctrl_handler, 0);
 	if (rc) {
 		stk1160_err("v4l2_ctrl_handler_init failed (%d)\n", rc);
 		goto free_err;
 	}

 	/*
 	 * We obtain a v4l2_dev but defer
 	 * registration of video device node as the last thing.
 	 * There is no need to set the name if we give a device struct
 	 */
 	dev->v4l2_dev.release = stk1160_release;
 	dev->v4l2_dev.ctrl_handler = &dev->ctrl_handler;
 	rc = v4l2_device_register(dev->dev, &dev->v4l2_dev);
 	if (rc) {
 		stk1160_err("v4l2_device_register failed (%d)\n", rc);
 		goto free_ctrl;
 	}

 	rc = stk1160_i2c_register(dev);
 	if (rc < 0)
 		goto unreg_v4l2;

 	/*
 	 * To the best of my knowledge stk1160 boards only have
 	 * saa7113, but it doesn't hurt to support them all.
 	 */
 	dev->sd_saa7115 = v4l2_i2c_new_subdev(&dev->v4l2_dev, &dev->i2c_adap,
 		"saa7115_auto", 0, saa7113_addrs);

 	/* i2c reset saa711x */
 	v4l2_device_call_all(&dev->v4l2_dev, 0, core, reset, 0);
 	v4l2_device_call_all(&dev->v4l2_dev, 0, video, s_stream, 0);

 	/* reset stk1160 to default values */
 	stk1160_reg_reset(dev);

 	/* select default input */
 	stk1160_select_input(dev);

 	stk1160_ac97_register(dev);

 	rc = stk1160_video_register(dev);
 	if (rc < 0)
 		goto unreg_i2c;

 	return 0;

 unreg_i2c:
 	stk1160_i2c_unregister(dev);
 unreg_v4l2:
 	v4l2_device_unregister(&dev->v4l2_dev);
 free_ctrl:
 	v4l2_ctrl_handler_free(&dev->ctrl_handler);
 free_err:
 	kfree(alt_max_pkt_size);
 	kfree(dev);

 	return rc;
 }

 static void stk1160_disconnect(struct usb_interface *interface)
 {
 	struct stk1160 *dev;

 	dev = usb_get_intfdata(interface);
 	usb_set_intfdata(interface, NULL);

 	/*
 	 * Wait until all current v4l2 operation are finished
 	 * then deallocate resources
 	 */
 	mutex_lock(&dev->vb_queue_lock);
 	mutex_lock(&dev->v4l_lock);

 	/* Here is the only place where isoc get released */
 	stk1160_uninit_isoc(dev);

 	/* ac97 unregister needs to be done before usb_device is cleared */
 	stk1160_ac97_unregister(dev);

 	stk1160_clear_queue(dev);

 	video_unregister_device(&dev->vdev);
 	v4l2_device_disconnect(&dev->v4l2_dev);

 	/* This way current users can detect device is gone */
 	dev->udev = NULL;

 	mutex_unlock(&dev->v4l_lock);
 	mutex_unlock(&dev->vb_queue_lock);

 	/*
 	 * This calls stk1160_release if it's the last reference.
 	 * therwise, release is posponed until there are no users left.
 	 */
 	v4l2_device_put(&dev->v4l2_dev);
 }

 static struct usb_driver stk1160_usb_driver = {
 	.name = "stk1160",
 	.id_table = stk1160_id_table,
 	.probe = stk1160_probe,
 	.disconnect = stk1160_disconnect,
 };

 module_usb_driver(stk1160_usb_driver);
	/*
	* STK1160 driver
	*
	* Copyright (C) 2012 Ezequiel Garcia
	* <elezegarcia--a.t--gmail.com>
	*
	* Based on Easycap driver by R.M. Thomas
	* Copyright (C) 2010 R.M. Thomas
	* <rmthomas--a.t--sciolus.org>
	*
	* 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.
	*
	* TODO:
	*
	* 1. (Try to) detect if we must register ac97 mixer
	* 2. Support stream at lower speed: lower frame rate or lower frame size.
	*
	*/

	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/slab.h>

	#include <linux/usb.h>
	#include <linux/mm.h>
	#include <linux/vmalloc.h>
	#include <media/saa7115.h>

	#include "stk1160.h"
	#include "stk1160-reg.h"

	static unsigned int input;
	module_param(input, int, 0644);
	MODULE_PARM_DESC(input, "Set default input");

	MODULE_LICENSE("GPL");
	MODULE_AUTHOR("Ezequiel Garcia");
	MODULE_DESCRIPTION("STK1160 driver");

	/* Devices supported by this driver */
	static struct usb_device_id stk1160_id_table[] = {
	{ USB_DEVICE(0x05e1, 0x0408) },
	{ }
	};
	MODULE_DEVICE_TABLE(usb, stk1160_id_table);

	/* saa7113 I2C address */
	static unsigned short saa7113_addrs[] = {
	0x4a >> 1,
	I2C_CLIENT_END
	};

	/*
	* Read/Write stk registers
	*/
	int stk1160_read_reg(struct stk1160 dev, u16 reg, u8 value)
	{
	int ret;
	int pipe = usb_rcvctrlpipe(dev->udev, 0);
	u8 *buf;

	*value = 0;

	buf = kmalloc(sizeof(u8), GFP_KERNEL);
	if (!buf)
	return -ENOMEM;
	ret = usb_control_msg(dev->udev, pipe, 0x00,
	USB_DIR_IN \| USB_TYPE_VENDOR \| USB_RECIP_DEVICE,
	0x00, reg, buf, sizeof(u8), HZ);
	if (ret < 0) {
	stk1160_err("read failed on reg 0x%x (%d)\n",
	reg, ret);
	kfree(buf);
	return ret;
	}

	value = buf;
	kfree(buf);
	return 0;
	}

	int stk1160_write_reg(struct stk1160 *dev, u16 reg, u16 value)
	{
	int ret;
	int pipe = usb_sndctrlpipe(dev->udev, 0);

	ret = usb_control_msg(dev->udev, pipe, 0x01,
	USB_DIR_OUT \| USB_TYPE_VENDOR \| USB_RECIP_DEVICE,
	value, reg, NULL, 0, HZ);
	if (ret < 0) {
	stk1160_err("write failed on reg 0x%x (%d)\n",
	reg, ret);
	return ret;
	}

	return 0;
	}

	void stk1160_select_input(struct stk1160 *dev)
	{
	int route;
	static const u8 gctrl[] = {
	0x98, 0x90, 0x88, 0x80, 0x98
	};

	if (dev->ctl_input == STK1160_SVIDEO_INPUT)
	route = SAA7115_SVIDEO3;
	else
	route = SAA7115_COMPOSITE0;

	if (dev->ctl_input < ARRAY_SIZE(gctrl)) {
	v4l2_device_call_all(&dev->v4l2_dev, 0, video, s_routing,
	route, 0, 0);
	stk1160_write_reg(dev, STK1160_GCTRL, gctrl[dev->ctl_input]);
	}
	}

	/* TODO: We should break this into pieces */
	static void stk1160_reg_reset(struct stk1160 *dev)
	{
	int i;

	static const struct regval ctl[] = {
	{STK1160_GCTRL+2, 0x0078},

	{STK1160_RMCTL+1, 0x0000},
	{STK1160_RMCTL+3, 0x0002},

	{STK1160_PLLSO, 0x0010},
	{STK1160_PLLSO+1, 0x0000},
	{STK1160_PLLSO+2, 0x0014},
	{STK1160_PLLSO+3, 0x000E},

	{STK1160_PLLFD, 0x0046},

	/* Timing generator setup */
	{STK1160_TIGEN, 0x0012},
	{STK1160_TICTL, 0x002D},
	{STK1160_TICTL+1, 0x0001},
	{STK1160_TICTL+2, 0x0000},
	{STK1160_TICTL+3, 0x0000},
	{STK1160_TIGEN, 0x0080},

	{0xffff, 0xffff}
	};

	for (i = 0; ctl[i].reg != 0xffff; i++)
	stk1160_write_reg(dev, ctl[i].reg, ctl[i].val);
	}

	static void stk1160_release(struct v4l2_device *v4l2_dev)
	{
	struct stk1160 *dev = container_of(v4l2_dev, struct stk1160, v4l2_dev);

	stk1160_dbg("releasing all resources\n");

	stk1160_i2c_unregister(dev);

	v4l2_ctrl_handler_free(&dev->ctrl_handler);
	v4l2_device_unregister(&dev->v4l2_dev);
	kfree(dev->alt_max_pkt_size);
	kfree(dev);
	}

	/* high bandwidth multiplier, as encoded in highspeed endpoint descriptors */
	#define hb_mult(wMaxPacketSize) (1 + (((wMaxPacketSize) >> 11) & 0x03))

	/*
	* Scan usb interface and populate max_pkt_size array
	* with information on each alternate setting.
	* The array should be allocated by the caller.
	*/
	static int stk1160_scan_usb(struct usb_interface intf, struct usb_device udev,
	unsigned int *max_pkt_size)
	{
	int i, e, sizedescr, size, ifnum;
	const struct usb_endpoint_descriptor *desc;

	bool has_video = false, has_audio = false;
	const char *speed;

	ifnum = intf->altsetting[0].desc.bInterfaceNumber;

	/* Get endpoints */
	for (i = 0; i < intf->num_altsetting; i++) {

	for (e = 0; e < intf->altsetting[i].desc.bNumEndpoints; e++) {

	/* This isn't clear enough, at least to me */
	desc = &intf->altsetting[i].endpoint[e].desc;
	sizedescr = le16_to_cpu(desc->wMaxPacketSize);
	size = sizedescr & 0x7ff;

	if (udev->speed == USB_SPEED_HIGH)
	size = size * hb_mult(sizedescr);

	if (usb_endpoint_xfer_isoc(desc) &&
	usb_endpoint_dir_in(desc)) {
	switch (desc->bEndpointAddress) {
	case STK1160_EP_AUDIO:
	has_audio = true;
	break;
	case STK1160_EP_VIDEO:
	has_video = true;
	max_pkt_size[i] = size;
	break;
	}
	}
	}
	}

	/* Is this even possible? */
	if (!(has_audio \|\| has_video)) {
	dev_err(&udev->dev, "no audio or video endpoints found\n");
	return -ENODEV;
	}

	switch (udev->speed) {
	case USB_SPEED_LOW:
	speed = "1.5";
	break;
	case USB_SPEED_FULL:
	speed = "12";
	break;
	case USB_SPEED_HIGH:
	speed = "480";
	break;
	default:
	speed = "unknown";
	}

	dev_info(&udev->dev, "New device %s %s @ %s Mbps (%04x:%04x, interface %d, class %d)\n",
	udev->manufacturer ? udev->manufacturer : "",
	udev->product ? udev->product : "",
	speed,
	le16_to_cpu(udev->descriptor.idVendor),
	le16_to_cpu(udev->descriptor.idProduct),
	ifnum,
	intf->altsetting->desc.bInterfaceNumber);

	/* This should never happen, since we rejected audio interfaces */
	if (has_audio)
	dev_warn(&udev->dev, "audio interface %d found.\n\
	This is not implemented by this driver,\
	you should use snd-usb-audio instead\n", ifnum);

	if (has_video)
	dev_info(&udev->dev, "video interface %d found\n",
	ifnum);

	/*
	* Make sure we have 480 Mbps of bandwidth, otherwise things like
	* video stream wouldn't likely work, since 12 Mbps is generally
	* not enough even for most streams.
	*/
	if (udev->speed != USB_SPEED_HIGH)
	dev_warn(&udev->dev, "must be connected to a high-speed USB 2.0 port\n\
	You may not be able to stream video smoothly\n");

	return 0;
	}

	static int stk1160_probe(struct usb_interface *interface,
	const struct usb_device_id *id)
	{
	int rc = 0;

	unsigned int alt_max_pkt_size; / array of wMaxPacketSize */
	struct usb_device *udev;
	struct stk1160 *dev;

	udev = interface_to_usbdev(interface);

	/*
	* Since usb audio class is supported by snd-usb-audio,
	* we reject audio interface.
	*/
	if (interface->altsetting[0].desc.bInterfaceClass == USB_CLASS_AUDIO)
	return -ENODEV;

	/* Alloc an array for all possible max_pkt_size */
	alt_max_pkt_size = kmalloc(sizeof(alt_max_pkt_size[0]) *
	interface->num_altsetting, GFP_KERNEL);
	if (alt_max_pkt_size == NULL)
	return -ENOMEM;

	/*
	* Scan usb posibilities and populate alt_max_pkt_size array.
	* Also, check if device speed is fast enough.
	*/
	rc = stk1160_scan_usb(interface, udev, alt_max_pkt_size);
	if (rc < 0) {
	kfree(alt_max_pkt_size);
	return rc;
	}

	dev = kzalloc(sizeof(struct stk1160), GFP_KERNEL);
	if (dev == NULL) {
	kfree(alt_max_pkt_size);
	return -ENOMEM;
	}

	dev->alt_max_pkt_size = alt_max_pkt_size;
	dev->udev = udev;
	dev->num_alt = interface->num_altsetting;
	dev->ctl_input = input;

	/* We save struct device for debug purposes only */
	dev->dev = &interface->dev;

	usb_set_intfdata(interface, dev);

	/* initialize videobuf2 stuff */
	rc = stk1160_vb2_setup(dev);
	if (rc < 0)
	goto free_err;

	/*
	* There is no need to take any locks here in probe
	* because we register the device node as the last thing.
	*/
	spin_lock_init(&dev->buf_lock);
	mutex_init(&dev->v4l_lock);
	mutex_init(&dev->vb_queue_lock);

	rc = v4l2_ctrl_handler_init(&dev->ctrl_handler, 0);
	if (rc) {
	stk1160_err("v4l2_ctrl_handler_init failed (%d)\n", rc);
	goto free_err;
	}

	/*
	* We obtain a v4l2_dev but defer
	* registration of video device node as the last thing.
	* There is no need to set the name if we give a device struct
	*/
	dev->v4l2_dev.release = stk1160_release;
	dev->v4l2_dev.ctrl_handler = &dev->ctrl_handler;
	rc = v4l2_device_register(dev->dev, &dev->v4l2_dev);
	if (rc) {
	stk1160_err("v4l2_device_register failed (%d)\n", rc);
	goto free_ctrl;
	}

	rc = stk1160_i2c_register(dev);
	if (rc < 0)
	goto unreg_v4l2;

	/*
	* To the best of my knowledge stk1160 boards only have
	* saa7113, but it doesn't hurt to support them all.
	*/
	dev->sd_saa7115 = v4l2_i2c_new_subdev(&dev->v4l2_dev, &dev->i2c_adap,
	"saa7115_auto", 0, saa7113_addrs);

	/* i2c reset saa711x */
	v4l2_device_call_all(&dev->v4l2_dev, 0, core, reset, 0);
	v4l2_device_call_all(&dev->v4l2_dev, 0, video, s_stream, 0);

	/* reset stk1160 to default values */
	stk1160_reg_reset(dev);

	/* select default input */
	stk1160_select_input(dev);

	stk1160_ac97_register(dev);

	rc = stk1160_video_register(dev);
	if (rc < 0)
	goto unreg_i2c;

	return 0;

	unreg_i2c:
	stk1160_i2c_unregister(dev);
	unreg_v4l2:
	v4l2_device_unregister(&dev->v4l2_dev);
	free_ctrl:
	v4l2_ctrl_handler_free(&dev->ctrl_handler);
	free_err:
	kfree(alt_max_pkt_size);
	kfree(dev);

	return rc;
	}

	static void stk1160_disconnect(struct usb_interface *interface)
	{
	struct stk1160 *dev;

	dev = usb_get_intfdata(interface);
	usb_set_intfdata(interface, NULL);

	/*
	* Wait until all current v4l2 operation are finished
	* then deallocate resources
	*/
	mutex_lock(&dev->vb_queue_lock);
	mutex_lock(&dev->v4l_lock);

	/* Here is the only place where isoc get released */
	stk1160_uninit_isoc(dev);

	/* ac97 unregister needs to be done before usb_device is cleared */
	stk1160_ac97_unregister(dev);

	stk1160_clear_queue(dev);

	video_unregister_device(&dev->vdev);
	v4l2_device_disconnect(&dev->v4l2_dev);

	/* This way current users can detect device is gone */
	dev->udev = NULL;

	mutex_unlock(&dev->v4l_lock);
	mutex_unlock(&dev->vb_queue_lock);

	/*
	* This calls stk1160_release if it's the last reference.
	* therwise, release is posponed until there are no users left.
	*/
	v4l2_device_put(&dev->v4l2_dev);
	}

	static struct usb_driver stk1160_usb_driver = {
	.name = "stk1160",
	.id_table = stk1160_id_table,
	.probe = stk1160_probe,
	.disconnect = stk1160_disconnect,
	};

	module_usb_driver(stk1160_usb_driver);