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USB gadget: video class function driver

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This USB video class function driver implements a video capture device from the
host's point of view. It creates a V4L2 output device on the gadget's side to
transfer data from a userspace application over USB.

The UVC-specific descriptors are passed by the gadget driver to the UVC
function driver, making them completely configurable without any modification
to the function's driver code.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Laurent Pinchart 2010-05-02 20:57:41 +02:00 committed by Greg Kroah-Hartman
parent 910f8d0ced
commit cdda479f15
7 changed files with 2710 additions and 0 deletions
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661
drivers/usb/gadget/f_uvc.c Normal file
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@ -0,0 +1,661 @@
/*
* uvc_gadget.c -- USB Video Class Gadget driver
*
* Copyright (C) 2009-2010
* Laurent Pinchart (laurent.pinchart@ideasonboard.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.
*
*/
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <linux/usb/video.h>
#include <linux/vmalloc.h>
#include <linux/wait.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-event.h>
#include "uvc.h"
unsigned int uvc_trace_param;
/* --------------------------------------------------------------------------
* Function descriptors
*/
/* string IDs are assigned dynamically */
#define UVC_STRING_ASSOCIATION_IDX 0
#define UVC_STRING_CONTROL_IDX 1
#define UVC_STRING_STREAMING_IDX 2
static struct usb_string uvc_en_us_strings[] = {
[UVC_STRING_ASSOCIATION_IDX].s = "UVC Camera",
[UVC_STRING_CONTROL_IDX].s = "Video Control",
[UVC_STRING_STREAMING_IDX].s = "Video Streaming",
{ }
};
static struct usb_gadget_strings uvc_stringtab = {
.language = 0x0409, /* en-us */
.strings = uvc_en_us_strings,
};
static struct usb_gadget_strings *uvc_function_strings[] = {
&uvc_stringtab,
NULL,
};
#define UVC_INTF_VIDEO_CONTROL 0
#define UVC_INTF_VIDEO_STREAMING 1
static struct usb_interface_assoc_descriptor uvc_iad __initdata = {
.bLength = USB_DT_INTERFACE_ASSOCIATION_SIZE,
.bDescriptorType = USB_DT_INTERFACE_ASSOCIATION,
.bFirstInterface = 0,
.bInterfaceCount = 2,
.bFunctionClass = USB_CLASS_VIDEO,
.bFunctionSubClass = 0x03,
.bFunctionProtocol = 0x00,
.iFunction = 0,
};
static struct usb_interface_descriptor uvc_control_intf __initdata = {
.bLength = USB_DT_INTERFACE_SIZE,
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = UVC_INTF_VIDEO_CONTROL,
.bAlternateSetting = 0,
.bNumEndpoints = 1,
.bInterfaceClass = USB_CLASS_VIDEO,
.bInterfaceSubClass = 0x01,
.bInterfaceProtocol = 0x00,
.iInterface = 0,
};
static struct usb_endpoint_descriptor uvc_control_ep __initdata = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = cpu_to_le16(16),
.bInterval = 8,
};
static struct uvc_control_endpoint_descriptor uvc_control_cs_ep __initdata = {
.bLength = UVC_DT_CONTROL_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_CS_ENDPOINT,
.bDescriptorSubType = UVC_EP_INTERRUPT,
.wMaxTransferSize = cpu_to_le16(16),
};
static struct usb_interface_descriptor uvc_streaming_intf_alt0 __initdata = {
.bLength = USB_DT_INTERFACE_SIZE,
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = UVC_INTF_VIDEO_STREAMING,
.bAlternateSetting = 0,
.bNumEndpoints = 0,
.bInterfaceClass = USB_CLASS_VIDEO,
.bInterfaceSubClass = 0x02,
.bInterfaceProtocol = 0x00,
.iInterface = 0,
};
static struct usb_interface_descriptor uvc_streaming_intf_alt1 __initdata = {
.bLength = USB_DT_INTERFACE_SIZE,
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = UVC_INTF_VIDEO_STREAMING,
.bAlternateSetting = 1,
.bNumEndpoints = 1,
.bInterfaceClass = USB_CLASS_VIDEO,
.bInterfaceSubClass = 0x02,
.bInterfaceProtocol = 0x00,
.iInterface = 0,
};
static struct usb_endpoint_descriptor uvc_streaming_ep = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_ISOC,
.wMaxPacketSize = cpu_to_le16(512),
.bInterval = 1,
};
static const struct usb_descriptor_header * const uvc_fs_streaming[] = {
(struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
(struct usb_descriptor_header *) &uvc_streaming_ep,
NULL,
};
static const struct usb_descriptor_header * const uvc_hs_streaming[] = {
(struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
(struct usb_descriptor_header *) &uvc_streaming_ep,
NULL,
};
/* --------------------------------------------------------------------------
* Control requests
*/
static void
uvc_function_ep0_complete(struct usb_ep *ep, struct usb_request *req)
{
struct uvc_device *uvc = req->context;
struct v4l2_event v4l2_event;
struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
if (uvc->event_setup_out) {
uvc->event_setup_out = 0;
memset(&v4l2_event, 0, sizeof(v4l2_event));
v4l2_event.type = UVC_EVENT_DATA;
uvc_event->data.length = req->actual;
memcpy(&uvc_event->data.data, req->buf, req->actual);
v4l2_event_queue(uvc->vdev, &v4l2_event);
}
}
static int
uvc_function_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
{
struct uvc_device *uvc = to_uvc(f);
struct v4l2_event v4l2_event;
struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
/* printk(KERN_INFO "setup request %02x %02x value %04x index %04x %04x\n",
* ctrl->bRequestType, ctrl->bRequest, le16_to_cpu(ctrl->wValue),
* le16_to_cpu(ctrl->wIndex), le16_to_cpu(ctrl->wLength));
*/
if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS) {
INFO(f->config->cdev, "invalid request type\n");
return -EINVAL;
}
/* Stall too big requests. */
if (le16_to_cpu(ctrl->wLength) > UVC_MAX_REQUEST_SIZE)
return -EINVAL;
memset(&v4l2_event, 0, sizeof(v4l2_event));
v4l2_event.type = UVC_EVENT_SETUP;
memcpy(&uvc_event->req, ctrl, sizeof(uvc_event->req));
v4l2_event_queue(uvc->vdev, &v4l2_event);
return 0;
}
static int
uvc_function_get_alt(struct usb_function *f, unsigned interface)
{
struct uvc_device *uvc = to_uvc(f);
INFO(f->config->cdev, "uvc_function_get_alt(%u)\n", interface);
if (interface == uvc->control_intf)
return 0;
else if (interface != uvc->streaming_intf)
return -EINVAL;
else
return uvc->state == UVC_STATE_STREAMING ? 1 : 0;
}
static int
uvc_function_set_alt(struct usb_function *f, unsigned interface, unsigned alt)
{
struct uvc_device *uvc = to_uvc(f);
struct v4l2_event v4l2_event;
struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
INFO(f->config->cdev, "uvc_function_set_alt(%u, %u)\n", interface, alt);
if (interface == uvc->control_intf) {
if (alt)
return -EINVAL;
if (uvc->state == UVC_STATE_DISCONNECTED) {
memset(&v4l2_event, 0, sizeof(v4l2_event));
v4l2_event.type = UVC_EVENT_CONNECT;
uvc_event->speed = f->config->cdev->gadget->speed;
v4l2_event_queue(uvc->vdev, &v4l2_event);
uvc->state = UVC_STATE_CONNECTED;
}
return 0;
}
if (interface != uvc->streaming_intf)
return -EINVAL;
/* TODO
if (usb_endpoint_xfer_bulk(&uvc->desc.vs_ep))
return alt ? -EINVAL : 0;
*/
switch (alt) {
case 0:
if (uvc->state != UVC_STATE_STREAMING)
return 0;
if (uvc->video.ep)
usb_ep_disable(uvc->video.ep);
memset(&v4l2_event, 0, sizeof(v4l2_event));
v4l2_event.type = UVC_EVENT_STREAMOFF;
v4l2_event_queue(uvc->vdev, &v4l2_event);
uvc->state = UVC_STATE_CONNECTED;
break;
case 1:
if (uvc->state != UVC_STATE_CONNECTED)
return 0;
if (uvc->video.ep)
usb_ep_enable(uvc->video.ep, &uvc_streaming_ep);
memset(&v4l2_event, 0, sizeof(v4l2_event));
v4l2_event.type = UVC_EVENT_STREAMON;
v4l2_event_queue(uvc->vdev, &v4l2_event);
uvc->state = UVC_STATE_STREAMING;
break;
default:
return -EINVAL;
}
return 0;
}
static void
uvc_function_disable(struct usb_function *f)
{
struct uvc_device *uvc = to_uvc(f);
struct v4l2_event v4l2_event;
INFO(f->config->cdev, "uvc_function_disable\n");
memset(&v4l2_event, 0, sizeof(v4l2_event));
v4l2_event.type = UVC_EVENT_DISCONNECT;
v4l2_event_queue(uvc->vdev, &v4l2_event);
uvc->state = UVC_STATE_DISCONNECTED;
}
/* --------------------------------------------------------------------------
* Connection / disconnection
*/
void
uvc_function_connect(struct uvc_device *uvc)
{
struct usb_composite_dev *cdev = uvc->func.config->cdev;
int ret;
if ((ret = usb_function_activate(&uvc->func)) < 0)
INFO(cdev, "UVC connect failed with %d\n", ret);
}
void
uvc_function_disconnect(struct uvc_device *uvc)
{
struct usb_composite_dev *cdev = uvc->func.config->cdev;
int ret;
if ((ret = usb_function_deactivate(&uvc->func)) < 0)
INFO(cdev, "UVC disconnect failed with %d\n", ret);
}
/* --------------------------------------------------------------------------
* USB probe and disconnect
*/
static int
uvc_register_video(struct uvc_device *uvc)
{
struct usb_composite_dev *cdev = uvc->func.config->cdev;
struct video_device *video;
/* TODO reference counting. */
video = video_device_alloc();
if (video == NULL)
return -ENOMEM;
video->parent = &cdev->gadget->dev;
video->minor = -1;
video->fops = &uvc_v4l2_fops;
video->release = video_device_release;
strncpy(video->name, cdev->gadget->name, sizeof(video->name));
uvc->vdev = video;
video_set_drvdata(video, uvc);
return video_register_device(video, VFL_TYPE_GRABBER, -1);
}
#define UVC_COPY_DESCRIPTOR(mem, dst, desc) \
do { \
memcpy(mem, desc, (desc)->bLength); \
*(dst)++ = mem; \
mem += (desc)->bLength; \
} while (0);
#define UVC_COPY_DESCRIPTORS(mem, dst, src) \
do { \
const struct usb_descriptor_header * const *__src; \
for (__src = src; *__src; ++__src) { \
memcpy(mem, *__src, (*__src)->bLength); \
*dst++ = mem; \
mem += (*__src)->bLength; \
} \
} while (0)
static struct usb_descriptor_header ** __init
uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
{
struct uvc_input_header_descriptor *uvc_streaming_header;
struct uvc_header_descriptor *uvc_control_header;
const struct uvc_descriptor_header * const *uvc_streaming_cls;
const struct usb_descriptor_header * const *uvc_streaming_std;
const struct usb_descriptor_header * const *src;
struct usb_descriptor_header **dst;
struct usb_descriptor_header **hdr;
unsigned int control_size;
unsigned int streaming_size;
unsigned int n_desc;
unsigned int bytes;
void *mem;
uvc_streaming_cls = (speed == USB_SPEED_FULL)
? uvc->desc.fs_streaming : uvc->desc.hs_streaming;
uvc_streaming_std = (speed == USB_SPEED_FULL)
? uvc_fs_streaming : uvc_hs_streaming;
/* Descriptors layout
*
* uvc_iad
* uvc_control_intf
* Class-specific UVC control descriptors
* uvc_control_ep
* uvc_control_cs_ep
* uvc_streaming_intf_alt0
* Class-specific UVC streaming descriptors
* uvc_{fs|hs}_streaming
*/
/* Count descriptors and compute their size. */
control_size = 0;
streaming_size = 0;
bytes = uvc_iad.bLength + uvc_control_intf.bLength
+ uvc_control_ep.bLength + uvc_control_cs_ep.bLength
+ uvc_streaming_intf_alt0.bLength;
n_desc = 5;
for (src = (const struct usb_descriptor_header**)uvc->desc.control; *src; ++src) {
control_size += (*src)->bLength;
bytes += (*src)->bLength;
n_desc++;
}
for (src = (const struct usb_descriptor_header**)uvc_streaming_cls; *src; ++src) {
streaming_size += (*src)->bLength;
bytes += (*src)->bLength;
n_desc++;
}
for (src = uvc_streaming_std; *src; ++src) {
bytes += (*src)->bLength;
n_desc++;
}
mem = kmalloc((n_desc + 1) * sizeof(*src) + bytes, GFP_KERNEL);
if (mem == NULL)
return NULL;
hdr = mem;
dst = mem;
mem += (n_desc + 1) * sizeof(*src);
/* Copy the descriptors. */
UVC_COPY_DESCRIPTOR(mem, dst, &uvc_iad);
UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_intf);
uvc_control_header = mem;
UVC_COPY_DESCRIPTORS(mem, dst,
(const struct usb_descriptor_header**)uvc->desc.control);
uvc_control_header->wTotalLength = cpu_to_le16(control_size);
uvc_control_header->bInCollection = 1;
uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_ep);
UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_cs_ep);
UVC_COPY_DESCRIPTOR(mem, dst, &uvc_streaming_intf_alt0);
uvc_streaming_header = mem;
UVC_COPY_DESCRIPTORS(mem, dst,
(const struct usb_descriptor_header**)uvc_streaming_cls);
uvc_streaming_header->wTotalLength = cpu_to_le16(streaming_size);
uvc_streaming_header->bEndpointAddress = uvc_streaming_ep.bEndpointAddress;
UVC_COPY_DESCRIPTORS(mem, dst, uvc_streaming_std);
*dst = NULL;
return hdr;
}
static void
uvc_function_unbind(struct usb_configuration *c, struct usb_function *f)
{
struct usb_composite_dev *cdev = c->cdev;
struct uvc_device *uvc = to_uvc(f);
INFO(cdev, "uvc_function_unbind\n");
if (uvc->vdev) {
if (uvc->vdev->minor == -1)
video_device_release(uvc->vdev);
else
video_unregister_device(uvc->vdev);
uvc->vdev = NULL;
}
if (uvc->control_ep)
uvc->control_ep->driver_data = NULL;
if (uvc->video.ep)
uvc->video.ep->driver_data = NULL;
if (uvc->control_req) {
usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
kfree(uvc->control_buf);
}
kfree(f->descriptors);
kfree(f->hs_descriptors);
kfree(uvc);
}
static int __init
uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
{
struct usb_composite_dev *cdev = c->cdev;
struct uvc_device *uvc = to_uvc(f);
struct usb_ep *ep;
int ret = -EINVAL;
INFO(cdev, "uvc_function_bind\n");
/* Allocate endpoints. */
ep = usb_ep_autoconfig(cdev->gadget, &uvc_control_ep);
if (!ep) {
INFO(cdev, "Unable to allocate control EP\n");
goto error;
}
uvc->control_ep = ep;
ep->driver_data = uvc;
ep = usb_ep_autoconfig(cdev->gadget, &uvc_streaming_ep);
if (!ep) {
INFO(cdev, "Unable to allocate streaming EP\n");
goto error;
}
uvc->video.ep = ep;
ep->driver_data = uvc;
/* Allocate interface IDs. */
if ((ret = usb_interface_id(c, f)) < 0)
goto error;
uvc_iad.bFirstInterface = ret;
uvc_control_intf.bInterfaceNumber = ret;
uvc->control_intf = ret;
if ((ret = usb_interface_id(c, f)) < 0)
goto error;
uvc_streaming_intf_alt0.bInterfaceNumber = ret;
uvc_streaming_intf_alt1.bInterfaceNumber = ret;
uvc->streaming_intf = ret;
/* Copy descriptors. */
f->descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
/* Preallocate control endpoint request. */
uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
if (uvc->control_req == NULL || uvc->control_buf == NULL) {
ret = -ENOMEM;
goto error;
}
uvc->control_req->buf = uvc->control_buf;
uvc->control_req->complete = uvc_function_ep0_complete;
uvc->control_req->context = uvc;
/* Avoid letting this gadget enumerate until the userspace server is
* active.
*/
if ((ret = usb_function_deactivate(f)) < 0)
goto error;
/* Initialise video. */
ret = uvc_video_init(&uvc->video);
if (ret < 0)
goto error;
/* Register a V4L2 device. */
ret = uvc_register_video(uvc);
if (ret < 0) {
printk(KERN_INFO "Unable to register video device\n");
goto error;
}
return 0;
error:
uvc_function_unbind(c, f);
return ret;
}
/* --------------------------------------------------------------------------
* USB gadget function
*/
/**
* uvc_bind_config - add a UVC function to a configuration
* @c: the configuration to support the UVC instance
* Context: single threaded during gadget setup
*
* Returns zero on success, else negative errno.
*
* Caller must have called @uvc_setup(). Caller is also responsible for
* calling @uvc_cleanup() before module unload.
*/
int __init
uvc_bind_config(struct usb_configuration *c,
const struct uvc_descriptor_header * const *control,
const struct uvc_descriptor_header * const *fs_streaming,
const struct uvc_descriptor_header * const *hs_streaming)
{
struct uvc_device *uvc;
int ret = 0;
/* TODO Check if the USB device controller supports the required
* features.
*/
if (!gadget_is_dualspeed(c->cdev->gadget))
return -EINVAL;
uvc = kzalloc(sizeof(*uvc), GFP_KERNEL);
if (uvc == NULL)
return -ENOMEM;
uvc->state = UVC_STATE_DISCONNECTED;
/* Validate the descriptors. */
if (control == NULL || control[0] == NULL ||
control[0]->bDescriptorSubType != UVC_DT_HEADER)
goto error;
if (fs_streaming == NULL || fs_streaming[0] == NULL ||
fs_streaming[0]->bDescriptorSubType != UVC_DT_INPUT_HEADER)
goto error;
if (hs_streaming == NULL || hs_streaming[0] == NULL ||
hs_streaming[0]->bDescriptorSubType != UVC_DT_INPUT_HEADER)
goto error;
uvc->desc.control = control;
uvc->desc.fs_streaming = fs_streaming;
uvc->desc.hs_streaming = hs_streaming;
/* Allocate string descriptor numbers. */
if ((ret = usb_string_id(c->cdev)) < 0)
goto error;
uvc_en_us_strings[UVC_STRING_ASSOCIATION_IDX].id = ret;
uvc_iad.iFunction = ret;
if ((ret = usb_string_id(c->cdev)) < 0)
goto error;
uvc_en_us_strings[UVC_STRING_CONTROL_IDX].id = ret;
uvc_control_intf.iInterface = ret;
if ((ret = usb_string_id(c->cdev)) < 0)
goto error;
uvc_en_us_strings[UVC_STRING_STREAMING_IDX].id = ret;
uvc_streaming_intf_alt0.iInterface = ret;
uvc_streaming_intf_alt1.iInterface = ret;
/* Register the function. */
uvc->func.name = "uvc";
uvc->func.strings = uvc_function_strings;
uvc->func.bind = uvc_function_bind;
uvc->func.unbind = uvc_function_unbind;
uvc->func.get_alt = uvc_function_get_alt;
uvc->func.set_alt = uvc_function_set_alt;
uvc->func.disable = uvc_function_disable;
uvc->func.setup = uvc_function_setup;
ret = usb_add_function(c, &uvc->func);
if (ret)
kfree(uvc);
return 0;
error:
kfree(uvc);
return ret;
}
module_param_named(trace, uvc_trace_param, uint, S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(trace, "Trace level bitmask");

376
drivers/usb/gadget/f_uvc.h Normal file
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/*
* f_uvc.h -- USB Video Class Gadget driver
*
* Copyright (C) 2009-2010
* Laurent Pinchart (laurent.pinchart@ideasonboard.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.
*
*/
#ifndef _F_UVC_H_
#define _F_UVC_H_
#include <linux/usb/composite.h>
#define USB_CLASS_VIDEO_CONTROL 1
#define USB_CLASS_VIDEO_STREAMING 2
struct uvc_descriptor_header {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
} __attribute__ ((packed));
struct uvc_header_descriptor {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u16 bcdUVC;
__u16 wTotalLength;
__u32 dwClockFrequency;
__u8 bInCollection;
__u8 baInterfaceNr[];
} __attribute__((__packed__));
#define UVC_HEADER_DESCRIPTOR(n) uvc_header_descriptor_##n
#define DECLARE_UVC_HEADER_DESCRIPTOR(n) \
struct UVC_HEADER_DESCRIPTOR(n) { \
__u8 bLength; \
__u8 bDescriptorType; \
__u8 bDescriptorSubType; \
__u16 bcdUVC; \
__u16 wTotalLength; \
__u32 dwClockFrequency; \
__u8 bInCollection; \
__u8 baInterfaceNr[n]; \
} __attribute__ ((packed))
struct uvc_input_terminal_descriptor {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bTerminalID;
__u16 wTerminalType;
__u8 bAssocTerminal;
__u8 iTerminal;
} __attribute__((__packed__));
struct uvc_output_terminal_descriptor {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bTerminalID;
__u16 wTerminalType;
__u8 bAssocTerminal;
__u8 bSourceID;
__u8 iTerminal;
} __attribute__((__packed__));
struct uvc_camera_terminal_descriptor {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bTerminalID;
__u16 wTerminalType;
__u8 bAssocTerminal;
__u8 iTerminal;
__u16 wObjectiveFocalLengthMin;
__u16 wObjectiveFocalLengthMax;
__u16 wOcularFocalLength;
__u8 bControlSize;
__u8 bmControls[3];
} __attribute__((__packed__));
struct uvc_selector_unit_descriptor {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bUnitID;
__u8 bNrInPins;
__u8 baSourceID[0];
__u8 iSelector;
} __attribute__((__packed__));
#define UVC_SELECTOR_UNIT_DESCRIPTOR(n) \
uvc_selector_unit_descriptor_##n
#define DECLARE_UVC_SELECTOR_UNIT_DESCRIPTOR(n) \
struct UVC_SELECTOR_UNIT_DESCRIPTOR(n) { \
__u8 bLength; \
__u8 bDescriptorType; \
__u8 bDescriptorSubType; \
__u8 bUnitID; \
__u8 bNrInPins; \
__u8 baSourceID[n]; \
__u8 iSelector; \
} __attribute__ ((packed))
struct uvc_processing_unit_descriptor {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bUnitID;
__u8 bSourceID;
__u16 wMaxMultiplier;
__u8 bControlSize;
__u8 bmControls[2];
__u8 iProcessing;
} __attribute__((__packed__));
struct uvc_extension_unit_descriptor {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bUnitID;
__u8 guidExtensionCode[16];
__u8 bNumControls;
__u8 bNrInPins;
__u8 baSourceID[0];
__u8 bControlSize;
__u8 bmControls[0];
__u8 iExtension;
} __attribute__((__packed__));
#define UVC_EXTENSION_UNIT_DESCRIPTOR(p, n) \
uvc_extension_unit_descriptor_##p_##n
#define DECLARE_UVC_EXTENSION_UNIT_DESCRIPTOR(p, n) \
struct UVC_EXTENSION_UNIT_DESCRIPTOR(p, n) { \
__u8 bLength; \
__u8 bDescriptorType; \
__u8 bDescriptorSubType; \
__u8 bUnitID; \
__u8 guidExtensionCode[16]; \
__u8 bNumControls; \
__u8 bNrInPins; \
__u8 baSourceID[p]; \
__u8 bControlSize; \
__u8 bmControls[n]; \
__u8 iExtension; \
} __attribute__ ((packed))
struct uvc_control_endpoint_descriptor {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u16 wMaxTransferSize;
} __attribute__((__packed__));
#define UVC_DT_HEADER 1
#define UVC_DT_INPUT_TERMINAL 2
#define UVC_DT_OUTPUT_TERMINAL 3
#define UVC_DT_SELECTOR_UNIT 4
#define UVC_DT_PROCESSING_UNIT 5
#define UVC_DT_EXTENSION_UNIT 6
#define UVC_DT_HEADER_SIZE(n) (12+(n))
#define UVC_DT_INPUT_TERMINAL_SIZE 8
#define UVC_DT_OUTPUT_TERMINAL_SIZE 9
#define UVC_DT_CAMERA_TERMINAL_SIZE(n) (15+(n))
#define UVC_DT_SELECTOR_UNIT_SIZE(n) (6+(n))
#define UVC_DT_PROCESSING_UNIT_SIZE(n) (9+(n))
#define UVC_DT_EXTENSION_UNIT_SIZE(p,n) (24+(p)+(n))
#define UVC_DT_CONTROL_ENDPOINT_SIZE 5
struct uvc_input_header_descriptor {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bNumFormats;
__u16 wTotalLength;
__u8 bEndpointAddress;
__u8 bmInfo;
__u8 bTerminalLink;
__u8 bStillCaptureMethod;
__u8 bTriggerSupport;
__u8 bTriggerUsage;
__u8 bControlSize;
__u8 bmaControls[];
} __attribute__((__packed__));
#define UVC_INPUT_HEADER_DESCRIPTOR(n, p) \
uvc_input_header_descriptor_##n_##p
#define DECLARE_UVC_INPUT_HEADER_DESCRIPTOR(n, p) \
struct UVC_INPUT_HEADER_DESCRIPTOR(n, p) { \
__u8 bLength; \
__u8 bDescriptorType; \
__u8 bDescriptorSubType; \
__u8 bNumFormats; \
__u16 wTotalLength; \
__u8 bEndpointAddress; \
__u8 bmInfo; \
__u8 bTerminalLink; \
__u8 bStillCaptureMethod; \
__u8 bTriggerSupport; \
__u8 bTriggerUsage; \
__u8 bControlSize; \
__u8 bmaControls[p][n]; \
} __attribute__ ((packed))
struct uvc_output_header_descriptor {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bNumFormats;
__u16 wTotalLength;
__u8 bEndpointAddress;
__u8 bTerminalLink;
__u8 bControlSize;
__u8 bmaControls[];
} __attribute__((__packed__));
#define UVC_OUTPUT_HEADER_DESCRIPTOR(n, p) \
uvc_output_header_descriptor_##n_##p
#define DECLARE_UVC_OUTPUT_HEADER_DESCRIPTOR(n, p) \
struct UVC_OUTPUT_HEADER_DESCRIPTOR(n, p) { \
__u8 bLength; \
__u8 bDescriptorType; \
__u8 bDescriptorSubType; \
__u8 bNumFormats; \
__u16 wTotalLength; \
__u8 bEndpointAddress; \
__u8 bTerminalLink; \
__u8 bControlSize; \
__u8 bmaControls[p][n]; \
} __attribute__ ((packed))
struct uvc_format_uncompressed {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bFormatIndex;
__u8 bNumFrameDescriptors;
__u8 guidFormat[16];
__u8 bBitsPerPixel;
__u8 bDefaultFrameIndex;
__u8 bAspectRatioX;
__u8 bAspectRatioY;
__u8 bmInterfaceFlags;
__u8 bCopyProtect;
} __attribute__((__packed__));
struct uvc_frame_uncompressed {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bFrameIndex;
__u8 bmCapabilities;
__u16 wWidth;
__u16 wHeight;
__u32 dwMinBitRate;
__u32 dwMaxBitRate;
__u32 dwMaxVideoFrameBufferSize;
__u32 dwDefaultFrameInterval;
__u8 bFrameIntervalType;
__u32 dwFrameInterval[];
} __attribute__((__packed__));
#define UVC_FRAME_UNCOMPRESSED(n) \
uvc_frame_uncompressed_##n
#define DECLARE_UVC_FRAME_UNCOMPRESSED(n) \
struct UVC_FRAME_UNCOMPRESSED(n) { \
__u8 bLength; \
__u8 bDescriptorType; \
__u8 bDescriptorSubType; \
__u8 bFrameIndex; \
__u8 bmCapabilities; \
__u16 wWidth; \
__u16 wHeight; \
__u32 dwMinBitRate; \
__u32 dwMaxBitRate; \
__u32 dwMaxVideoFrameBufferSize; \
__u32 dwDefaultFrameInterval; \
__u8 bFrameIntervalType; \
__u32 dwFrameInterval[n]; \
} __attribute__ ((packed))
struct uvc_format_mjpeg {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bFormatIndex;
__u8 bNumFrameDescriptors;
__u8 bmFlags;
__u8 bDefaultFrameIndex;
__u8 bAspectRatioX;
__u8 bAspectRatioY;
__u8 bmInterfaceFlags;
__u8 bCopyProtect;
} __attribute__((__packed__));
struct uvc_frame_mjpeg {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bFrameIndex;
__u8 bmCapabilities;
__u16 wWidth;
__u16 wHeight;
__u32 dwMinBitRate;
__u32 dwMaxBitRate;
__u32 dwMaxVideoFrameBufferSize;
__u32 dwDefaultFrameInterval;
__u8 bFrameIntervalType;
__u32 dwFrameInterval[];
} __attribute__((__packed__));
#define UVC_FRAME_MJPEG(n) \
uvc_frame_mjpeg_##n
#define DECLARE_UVC_FRAME_MJPEG(n) \
struct UVC_FRAME_MJPEG(n) { \
__u8 bLength; \
__u8 bDescriptorType; \
__u8 bDescriptorSubType; \
__u8 bFrameIndex; \
__u8 bmCapabilities; \
__u16 wWidth; \
__u16 wHeight; \
__u32 dwMinBitRate; \
__u32 dwMaxBitRate; \
__u32 dwMaxVideoFrameBufferSize; \
__u32 dwDefaultFrameInterval; \
__u8 bFrameIntervalType; \
__u32 dwFrameInterval[n]; \
} __attribute__ ((packed))
struct uvc_color_matching_descriptor {
__u8 bLength;
__u8 bDescriptorType;
__u8 bDescriptorSubType;
__u8 bColorPrimaries;
__u8 bTransferCharacteristics;
__u8 bMatrixCoefficients;
} __attribute__((__packed__));
#define UVC_DT_INPUT_HEADER 1
#define UVC_DT_OUTPUT_HEADER 2
#define UVC_DT_FORMAT_UNCOMPRESSED 4
#define UVC_DT_FRAME_UNCOMPRESSED 5
#define UVC_DT_FORMAT_MJPEG 6
#define UVC_DT_FRAME_MJPEG 7
#define UVC_DT_COLOR_MATCHING 13
#define UVC_DT_INPUT_HEADER_SIZE(n, p) (13+(n*p))
#define UVC_DT_OUTPUT_HEADER_SIZE(n, p) (9+(n*p))
#define UVC_DT_FORMAT_UNCOMPRESSED_SIZE 27
#define UVC_DT_FRAME_UNCOMPRESSED_SIZE(n) (26+4*(n))
#define UVC_DT_FORMAT_MJPEG_SIZE 11
#define UVC_DT_FRAME_MJPEG_SIZE(n) (26+4*(n))
#define UVC_DT_COLOR_MATCHING_SIZE 6
extern int uvc_bind_config(struct usb_configuration *c,
const struct uvc_descriptor_header * const *control,
const struct uvc_descriptor_header * const *fs_streaming,
const struct uvc_descriptor_header * const *hs_streaming);
#endif /* _F_UVC_H_ */

241
drivers/usb/gadget/uvc.h Normal file
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/*
* uvc_gadget.h -- USB Video Class Gadget driver
*
* Copyright (C) 2009-2010
* Laurent Pinchart (laurent.pinchart@ideasonboard.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.
*
*/
#ifndef _UVC_GADGET_H_
#define _UVC_GADGET_H_
#include <linux/ioctl.h>
#include <linux/types.h>
#include <linux/usb/ch9.h>
#define UVC_EVENT_FIRST (V4L2_EVENT_PRIVATE_START + 0)
#define UVC_EVENT_CONNECT (V4L2_EVENT_PRIVATE_START + 0)
#define UVC_EVENT_DISCONNECT (V4L2_EVENT_PRIVATE_START + 1)
#define UVC_EVENT_STREAMON (V4L2_EVENT_PRIVATE_START + 2)
#define UVC_EVENT_STREAMOFF (V4L2_EVENT_PRIVATE_START + 3)
#define UVC_EVENT_SETUP (V4L2_EVENT_PRIVATE_START + 4)
#define UVC_EVENT_DATA (V4L2_EVENT_PRIVATE_START + 5)
#define UVC_EVENT_LAST (V4L2_EVENT_PRIVATE_START + 5)
struct uvc_request_data
{
unsigned int length;
__u8 data[60];
};
struct uvc_event
{
union {
enum usb_device_speed speed;
struct usb_ctrlrequest req;
struct uvc_request_data data;
};
};
#define UVCIOC_SEND_RESPONSE _IOW('U', 1, struct uvc_request_data)
#define UVC_INTF_CONTROL 0
#define UVC_INTF_STREAMING 1
/* ------------------------------------------------------------------------
* UVC constants & structures
*/
/* Values for bmHeaderInfo (Video and Still Image Payload Headers, 2.4.3.3) */
#define UVC_STREAM_EOH (1 << 7)
#define UVC_STREAM_ERR (1 << 6)
#define UVC_STREAM_STI (1 << 5)
#define UVC_STREAM_RES (1 << 4)
#define UVC_STREAM_SCR (1 << 3)
#define UVC_STREAM_PTS (1 << 2)
#define UVC_STREAM_EOF (1 << 1)
#define UVC_STREAM_FID (1 << 0)
struct uvc_streaming_control {
__u16 bmHint;
__u8 bFormatIndex;
__u8 bFrameIndex;
__u32 dwFrameInterval;
__u16 wKeyFrameRate;
__u16 wPFrameRate;
__u16 wCompQuality;
__u16 wCompWindowSize;
__u16 wDelay;
__u32 dwMaxVideoFrameSize;
__u32 dwMaxPayloadTransferSize;
__u32 dwClockFrequency;
__u8 bmFramingInfo;
__u8 bPreferedVersion;
__u8 bMinVersion;
__u8 bMaxVersion;
} __attribute__((__packed__));
/* ------------------------------------------------------------------------
* Debugging, printing and logging
*/
#ifdef __KERNEL__
#include <linux/usb.h> /* For usb_endpoint_* */
#include <linux/usb/gadget.h>
#include <linux/videodev2.h>
#include <media/v4l2-fh.h>
#include "uvc_queue.h"
#define UVC_TRACE_PROBE (1 << 0)
#define UVC_TRACE_DESCR (1 << 1)
#define UVC_TRACE_CONTROL (1 << 2)
#define UVC_TRACE_FORMAT (1 << 3)
#define UVC_TRACE_CAPTURE (1 << 4)
#define UVC_TRACE_CALLS (1 << 5)
#define UVC_TRACE_IOCTL (1 << 6)
#define UVC_TRACE_FRAME (1 << 7)
#define UVC_TRACE_SUSPEND (1 << 8)
#define UVC_TRACE_STATUS (1 << 9)
#define UVC_WARN_MINMAX 0
#define UVC_WARN_PROBE_DEF 1
extern unsigned int uvc_trace_param;
#define uvc_trace(flag, msg...) \
do { \
if (uvc_trace_param & flag) \
printk(KERN_DEBUG "uvcvideo: " msg); \
} while (0)
#define uvc_warn_once(dev, warn, msg...) \
do { \
if (!test_and_set_bit(warn, &dev->warnings)) \
printk(KERN_INFO "uvcvideo: " msg); \
} while (0)
#define uvc_printk(level, msg...) \
printk(level "uvcvideo: " msg)
/* ------------------------------------------------------------------------
* Driver specific constants
*/
#define DRIVER_VERSION "0.1.0"
#define DRIVER_VERSION_NUMBER KERNEL_VERSION(0, 1, 0)
#define DMA_ADDR_INVALID (~(dma_addr_t)0)
#define UVC_NUM_REQUESTS 4
#define UVC_MAX_REQUEST_SIZE 64
#define UVC_MAX_EVENTS 4
#define USB_DT_INTERFACE_ASSOCIATION_SIZE 8
#define USB_CLASS_MISC 0xef
/* ------------------------------------------------------------------------
* Structures
*/
struct uvc_video
{
struct usb_ep *ep;
/* Frame parameters */
u8 bpp;
u32 fcc;
unsigned int width;
unsigned int height;
unsigned int imagesize;
/* Requests */
unsigned int req_size;
struct usb_request *req[UVC_NUM_REQUESTS];
__u8 *req_buffer[UVC_NUM_REQUESTS];
struct list_head req_free;
spinlock_t req_lock;
void (*encode) (struct usb_request *req, struct uvc_video *video,
struct uvc_buffer *buf);
/* Context data used by the completion handler */
__u32 payload_size;
__u32 max_payload_size;
struct uvc_video_queue queue;
unsigned int fid;
};
enum uvc_state
{
UVC_STATE_DISCONNECTED,
UVC_STATE_CONNECTED,
UVC_STATE_STREAMING,
};
struct uvc_device
{
struct video_device *vdev;
enum uvc_state state;
struct usb_function func;
struct uvc_video video;
/* Descriptors */
struct {
const struct uvc_descriptor_header * const *control;
const struct uvc_descriptor_header * const *fs_streaming;
const struct uvc_descriptor_header * const *hs_streaming;
} desc;
unsigned int control_intf;
struct usb_ep *control_ep;
struct usb_request *control_req;
void *control_buf;
unsigned int streaming_intf;
/* Events */
unsigned int event_length;
unsigned int event_setup_out : 1;
};
static inline struct uvc_device *to_uvc(struct usb_function *f)
{
return container_of(f, struct uvc_device, func);
}
struct uvc_file_handle
{
struct v4l2_fh vfh;
struct uvc_video *device;
};
#define to_uvc_file_handle(handle) \
container_of(handle, struct uvc_file_handle, vfh)
extern struct v4l2_file_operations uvc_v4l2_fops;
/* ------------------------------------------------------------------------
* Functions
*/
extern int uvc_video_enable(struct uvc_video *video, int enable);
extern int uvc_video_init(struct uvc_video *video);
extern int uvc_video_pump(struct uvc_video *video);
extern void uvc_endpoint_stream(struct uvc_device *dev);
extern void uvc_function_connect(struct uvc_device *uvc);
extern void uvc_function_disconnect(struct uvc_device *uvc);
#endif /* __KERNEL__ */
#endif /* _UVC_GADGET_H_ */

583
drivers/usb/gadget/uvc_queue.c Normal file
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/*
* uvc_queue.c -- USB Video Class driver - Buffers management
*
* Copyright (C) 2005-2010
* Laurent Pinchart (laurent.pinchart@ideasonboard.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.
*
*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/videodev2.h>
#include <linux/vmalloc.h>
#include <linux/wait.h>
#include <asm/atomic.h>
#include "uvc.h"
/* ------------------------------------------------------------------------
* Video buffers queue management.
*
* Video queues is initialized by uvc_queue_init(). The function performs
* basic initialization of the uvc_video_queue struct and never fails.
*
* Video buffer allocation and freeing are performed by uvc_alloc_buffers and
* uvc_free_buffers respectively. The former acquires the video queue lock,
* while the later must be called with the lock held (so that allocation can
* free previously allocated buffers). Trying to free buffers that are mapped
* to user space will return -EBUSY.
*
* Video buffers are managed using two queues. However, unlike most USB video
* drivers that use an in queue and an out queue, we use a main queue to hold
* all queued buffers (both 'empty' and 'done' buffers), and an irq queue to
* hold empty buffers. This design (copied from video-buf) minimizes locking
* in interrupt, as only one queue is shared between interrupt and user
* contexts.
*
* Use cases
* ---------
*
* Unless stated otherwise, all operations that modify the irq buffers queue
* are protected by the irq spinlock.
*
* 1. The user queues the buffers, starts streaming and dequeues a buffer.
*
* The buffers are added to the main and irq queues. Both operations are
* protected by the queue lock, and the later is protected by the irq
* spinlock as well.
*
* The completion handler fetches a buffer from the irq queue and fills it
* with video data. If no buffer is available (irq queue empty), the handler
* returns immediately.
*
* When the buffer is full, the completion handler removes it from the irq
* queue, marks it as ready (UVC_BUF_STATE_DONE) and wakes its wait queue.
* At that point, any process waiting on the buffer will be woken up. If a
* process tries to dequeue a buffer after it has been marked ready, the
* dequeing will succeed immediately.
*
* 2. Buffers are queued, user is waiting on a buffer and the device gets
* disconnected.
*
* When the device is disconnected, the kernel calls the completion handler
* with an appropriate status code. The handler marks all buffers in the
* irq queue as being erroneous (UVC_BUF_STATE_ERROR) and wakes them up so
* that any process waiting on a buffer gets woken up.
*
* Waking up up the first buffer on the irq list is not enough, as the
* process waiting on the buffer might restart the dequeue operation
* immediately.
*
*/
void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type)
{
mutex_init(&queue->mutex);
spin_lock_init(&queue->irqlock);
INIT_LIST_HEAD(&queue->mainqueue);
INIT_LIST_HEAD(&queue->irqqueue);
queue->type = type;
}
/*
* Allocate the video buffers.
*
* Pages are reserved to make sure they will not be swapped, as they will be
* filled in the URB completion handler.
*
* Buffers will be individually mapped, so they must all be page aligned.
*/
int uvc_alloc_buffers(struct uvc_video_queue *queue, unsigned int nbuffers,
unsigned int buflength)
{
unsigned int bufsize = PAGE_ALIGN(buflength);
unsigned int i;
void *mem = NULL;
int ret;
if (nbuffers > UVC_MAX_VIDEO_BUFFERS)
nbuffers = UVC_MAX_VIDEO_BUFFERS;
mutex_lock(&queue->mutex);
if ((ret = uvc_free_buffers(queue)) < 0)
goto done;
/* Bail out if no buffers should be allocated. */
if (nbuffers == 0)
goto done;
/* Decrement the number of buffers until allocation succeeds. */
for (; nbuffers > 0; --nbuffers) {
mem = vmalloc_32(nbuffers * bufsize);
if (mem != NULL)
break;
}
if (mem == NULL) {
ret = -ENOMEM;
goto done;
}
for (i = 0; i < nbuffers; ++i) {
memset(&queue->buffer[i], 0, sizeof queue->buffer[i]);
queue->buffer[i].buf.index = i;
queue->buffer[i].buf.m.offset = i * bufsize;
queue->buffer[i].buf.length = buflength;
queue->buffer[i].buf.type = queue->type;
queue->buffer[i].buf.sequence = 0;
queue->buffer[i].buf.field = V4L2_FIELD_NONE;
queue->buffer[i].buf.memory = V4L2_MEMORY_MMAP;
queue->buffer[i].buf.flags = 0;
init_waitqueue_head(&queue->buffer[i].wait);
}
queue->mem = mem;
queue->count = nbuffers;
queue->buf_size = bufsize;
ret = nbuffers;
done:
mutex_unlock(&queue->mutex);
return ret;
}
/*
* Free the video buffers.
*
* This function must be called with the queue lock held.
*/
int uvc_free_buffers(struct uvc_video_queue *queue)
{
unsigned int i;
for (i = 0; i < queue->count; ++i) {
if (queue->buffer[i].vma_use_count != 0)
return -EBUSY;
}
if (queue->count) {
vfree(queue->mem);
queue->count = 0;
}
return 0;
}
static void __uvc_query_buffer(struct uvc_buffer *buf,
struct v4l2_buffer *v4l2_buf)
{
memcpy(v4l2_buf, &buf->buf, sizeof *v4l2_buf);
if (buf->vma_use_count)
v4l2_buf->flags |= V4L2_BUF_FLAG_MAPPED;
switch (buf->state) {
case UVC_BUF_STATE_ERROR:
case UVC_BUF_STATE_DONE:
v4l2_buf->flags |= V4L2_BUF_FLAG_DONE;
break;
case UVC_BUF_STATE_QUEUED:
case UVC_BUF_STATE_ACTIVE:
v4l2_buf->flags |= V4L2_BUF_FLAG_QUEUED;
break;
case UVC_BUF_STATE_IDLE:
default:
break;
}
}
int uvc_query_buffer(struct uvc_video_queue *queue,
struct v4l2_buffer *v4l2_buf)
{
int ret = 0;
mutex_lock(&queue->mutex);
if (v4l2_buf->index >= queue->count) {
ret = -EINVAL;
goto done;
}
__uvc_query_buffer(&queue->buffer[v4l2_buf->index], v4l2_buf);
done:
mutex_unlock(&queue->mutex);
return ret;
}
/*
* Queue a video buffer. Attempting to queue a buffer that has already been
* queued will return -EINVAL.
*/
int uvc_queue_buffer(struct uvc_video_queue *queue,
struct v4l2_buffer *v4l2_buf)
{
struct uvc_buffer *buf;
unsigned long flags;
int ret = 0;
uvc_trace(UVC_TRACE_CAPTURE, "Queuing buffer %u.\n", v4l2_buf->index);
if (v4l2_buf->type != queue->type ||
v4l2_buf->memory != V4L2_MEMORY_MMAP) {
uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer type (%u) "
"and/or memory (%u).\n", v4l2_buf->type,
v4l2_buf->memory);
return -EINVAL;
}
mutex_lock(&queue->mutex);
if (v4l2_buf->index >= queue->count) {
uvc_trace(UVC_TRACE_CAPTURE, "[E] Out of range index.\n");
ret = -EINVAL;
goto done;
}
buf = &queue->buffer[v4l2_buf->index];
if (buf->state != UVC_BUF_STATE_IDLE) {
uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer state "
"(%u).\n", buf->state);
ret = -EINVAL;
goto done;
}
if (v4l2_buf->type == V4L2_BUF_TYPE_VIDEO_OUTPUT &&
v4l2_buf->bytesused > buf->buf.length) {
uvc_trace(UVC_TRACE_CAPTURE, "[E] Bytes used out of bounds.\n");
ret = -EINVAL;
goto done;
}
if (v4l2_buf->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
buf->buf.bytesused = 0;
else
buf->buf.bytesused = v4l2_buf->bytesused;
spin_lock_irqsave(&queue->irqlock, flags);
if (queue->flags & UVC_QUEUE_DISCONNECTED) {
spin_unlock_irqrestore(&queue->irqlock, flags);
ret = -ENODEV;
goto done;
}
buf->state = UVC_BUF_STATE_QUEUED;
ret = (queue->flags & UVC_QUEUE_PAUSED) != 0;
queue->flags &= ~UVC_QUEUE_PAUSED;
list_add_tail(&buf->stream, &queue->mainqueue);
list_add_tail(&buf->queue, &queue->irqqueue);
spin_unlock_irqrestore(&queue->irqlock, flags);
done:
mutex_unlock(&queue->mutex);
return ret;
}
static int uvc_queue_waiton(struct uvc_buffer *buf, int nonblocking)
{
if (nonblocking) {
return (buf->state != UVC_BUF_STATE_QUEUED &&
buf->state != UVC_BUF_STATE_ACTIVE)
? 0 : -EAGAIN;
}
return wait_event_interruptible(buf->wait,
buf->state != UVC_BUF_STATE_QUEUED &&
buf->state != UVC_BUF_STATE_ACTIVE);
}
/*
* Dequeue a video buffer. If nonblocking is false, block until a buffer is
* available.
*/
int uvc_dequeue_buffer(struct uvc_video_queue *queue,
struct v4l2_buffer *v4l2_buf, int nonblocking)
{
struct uvc_buffer *buf;
int ret = 0;
if (v4l2_buf->type != queue->type ||
v4l2_buf->memory != V4L2_MEMORY_MMAP) {
uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer type (%u) "
"and/or memory (%u).\n", v4l2_buf->type,
v4l2_buf->memory);
return -EINVAL;
}
mutex_lock(&queue->mutex);
if (list_empty(&queue->mainqueue)) {
uvc_trace(UVC_TRACE_CAPTURE, "[E] Empty buffer queue.\n");
ret = -EINVAL;
goto done;
}
buf = list_first_entry(&queue->mainqueue, struct uvc_buffer, stream);
if ((ret = uvc_queue_waiton(buf, nonblocking)) < 0)
goto done;
uvc_trace(UVC_TRACE_CAPTURE, "Dequeuing buffer %u (%u, %u bytes).\n",
buf->buf.index, buf->state, buf->buf.bytesused);
switch (buf->state) {
case UVC_BUF_STATE_ERROR:
uvc_trace(UVC_TRACE_CAPTURE, "[W] Corrupted data "
"(transmission error).\n");
ret = -EIO;
case UVC_BUF_STATE_DONE:
buf->state = UVC_BUF_STATE_IDLE;
break;
case UVC_BUF_STATE_IDLE:
case UVC_BUF_STATE_QUEUED:
case UVC_BUF_STATE_ACTIVE:
default:
uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer state %u "
"(driver bug?).\n", buf->state);
ret = -EINVAL;
goto done;
}
list_del(&buf->stream);
__uvc_query_buffer(buf, v4l2_buf);
done:
mutex_unlock(&queue->mutex);
return ret;
}
/*
* Poll the video queue.
*
* This function implements video queue polling and is intended to be used by
* the device poll handler.
*/
unsigned int uvc_queue_poll(struct uvc_video_queue *queue, struct file *file,
poll_table *wait)
{
struct uvc_buffer *buf;
unsigned int mask = 0;
mutex_lock(&queue->mutex);
if (list_empty(&queue->mainqueue))
goto done;
buf = list_first_entry(&queue->mainqueue, struct uvc_buffer, stream);
poll_wait(file, &buf->wait, wait);
if (buf->state == UVC_BUF_STATE_DONE ||
buf->state == UVC_BUF_STATE_ERROR)
mask |= POLLOUT | POLLWRNORM;
done:
mutex_unlock(&queue->mutex);
return mask;
}
/*
* VMA operations.
*/
static void uvc_vm_open(struct vm_area_struct *vma)
{
struct uvc_buffer *buffer = vma->vm_private_data;
buffer->vma_use_count++;
}
static void uvc_vm_close(struct vm_area_struct *vma)
{
struct uvc_buffer *buffer = vma->vm_private_data;
buffer->vma_use_count--;
}
static struct vm_operations_struct uvc_vm_ops = {
.open = uvc_vm_open,
.close = uvc_vm_close,
};
/*
* Memory-map a buffer.
*
* This function implements video buffer memory mapping and is intended to be
* used by the device mmap handler.
*/
int uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
{
struct uvc_buffer *uninitialized_var(buffer);
struct page *page;
unsigned long addr, start, size;
unsigned int i;
int ret = 0;
start = vma->vm_start;
size = vma->vm_end - vma->vm_start;
mutex_lock(&queue->mutex);
for (i = 0; i < queue->count; ++i) {
buffer = &queue->buffer[i];
if ((buffer->buf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff)
break;
}
if (i == queue->count || size != queue->buf_size) {
ret = -EINVAL;
goto done;
}
/*
* VM_IO marks the area as being an mmaped region for I/O to a
* device. It also prevents the region from being core dumped.
*/
vma->vm_flags |= VM_IO;
addr = (unsigned long)queue->mem + buffer->buf.m.offset;
while (size > 0) {
page = vmalloc_to_page((void *)addr);
if ((ret = vm_insert_page(vma, start, page)) < 0)
goto done;
start += PAGE_SIZE;
addr += PAGE_SIZE;
size -= PAGE_SIZE;
}
vma->vm_ops = &uvc_vm_ops;
vma->vm_private_data = buffer;
uvc_vm_open(vma);
done:
mutex_unlock(&queue->mutex);
return ret;
}
/*
* Enable or disable the video buffers queue.
*
* The queue must be enabled before starting video acquisition and must be
* disabled after stopping it. This ensures that the video buffers queue
* state can be properly initialized before buffers are accessed from the
* interrupt handler.
*
* Enabling the video queue initializes parameters (such as sequence number,
* sync pattern, ...). If the queue is already enabled, return -EBUSY.
*
* Disabling the video queue cancels the queue and removes all buffers from
* the main queue.
*
* This function can't be called from interrupt context. Use
* uvc_queue_cancel() instead.
*/
int uvc_queue_enable(struct uvc_video_queue *queue, int enable)
{
unsigned int i;
int ret = 0;
mutex_lock(&queue->mutex);
if (enable) {
if (uvc_queue_streaming(queue)) {
ret = -EBUSY;
goto done;
}
queue->sequence = 0;
queue->flags |= UVC_QUEUE_STREAMING;
queue->buf_used = 0;
} else {
uvc_queue_cancel(queue, 0);
INIT_LIST_HEAD(&queue->mainqueue);
for (i = 0; i < queue->count; ++i)
queue->buffer[i].state = UVC_BUF_STATE_IDLE;
queue->flags &= ~UVC_QUEUE_STREAMING;
}
done:
mutex_unlock(&queue->mutex);
return ret;
}
/*
* Cancel the video buffers queue.
*
* Cancelling the queue marks all buffers on the irq queue as erroneous,
* wakes them up and removes them from the queue.
*
* If the disconnect parameter is set, further calls to uvc_queue_buffer will
* fail with -ENODEV.
*
* This function acquires the irq spinlock and can be called from interrupt
* context.
*/
void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect)
{
struct uvc_buffer *buf;
unsigned long flags;
spin_lock_irqsave(&queue->irqlock, flags);
while (!list_empty(&queue->irqqueue)) {
buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
queue);
list_del(&buf->queue);
buf->state = UVC_BUF_STATE_ERROR;
wake_up(&buf->wait);
}
/* This must be protected by the irqlock spinlock to avoid race
* conditions between uvc_queue_buffer and the disconnection event that
* could result in an interruptible wait in uvc_dequeue_buffer. Do not
* blindly replace this logic by checking for the UVC_DEV_DISCONNECTED
* state outside the queue code.
*/
if (disconnect)
queue->flags |= UVC_QUEUE_DISCONNECTED;
spin_unlock_irqrestore(&queue->irqlock, flags);
}
struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
struct uvc_buffer *buf)
{
struct uvc_buffer *nextbuf;
unsigned long flags;
if ((queue->flags & UVC_QUEUE_DROP_INCOMPLETE) &&
buf->buf.length != buf->buf.bytesused) {
buf->state = UVC_BUF_STATE_QUEUED;
buf->buf.bytesused = 0;
return buf;
}
spin_lock_irqsave(&queue->irqlock, flags);
list_del(&buf->queue);
if (!list_empty(&queue->irqqueue))
nextbuf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
queue);
else
nextbuf = NULL;
spin_unlock_irqrestore(&queue->irqlock, flags);
buf->buf.sequence = queue->sequence++;
do_gettimeofday(&buf->buf.timestamp);
wake_up(&buf->wait);
return nextbuf;
}
struct uvc_buffer *uvc_queue_head(struct uvc_video_queue *queue)
{
struct uvc_buffer *buf = NULL;
if (!list_empty(&queue->irqqueue))
buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
queue);
else
queue->flags |= UVC_QUEUE_PAUSED;
return buf;
}

89
drivers/usb/gadget/uvc_queue.h Normal file
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#ifndef _UVC_QUEUE_H_
#define _UVC_QUEUE_H_
#ifdef __KERNEL__
#include <linux/kernel.h>
#include <linux/poll.h>
#include <linux/videodev2.h>
/* Maximum frame size in bytes, for sanity checking. */
#define UVC_MAX_FRAME_SIZE (16*1024*1024)
/* Maximum number of video buffers. */
#define UVC_MAX_VIDEO_BUFFERS 32
/* ------------------------------------------------------------------------
* Structures.
*/
enum uvc_buffer_state {
UVC_BUF_STATE_IDLE = 0,
UVC_BUF_STATE_QUEUED = 1,
UVC_BUF_STATE_ACTIVE = 2,
UVC_BUF_STATE_DONE = 3,
UVC_BUF_STATE_ERROR = 4,
};
struct uvc_buffer {
unsigned long vma_use_count;
struct list_head stream;
/* Touched by interrupt handler. */
struct v4l2_buffer buf;
struct list_head queue;
wait_queue_head_t wait;
enum uvc_buffer_state state;
};
#define UVC_QUEUE_STREAMING (1 << 0)
#define UVC_QUEUE_DISCONNECTED (1 << 1)
#define UVC_QUEUE_DROP_INCOMPLETE (1 << 2)
#define UVC_QUEUE_PAUSED (1 << 3)
struct uvc_video_queue {
enum v4l2_buf_type type;
void *mem;
unsigned int flags;
__u32 sequence;
unsigned int count;
unsigned int buf_size;
unsigned int buf_used;
struct uvc_buffer buffer[UVC_MAX_VIDEO_BUFFERS];
struct mutex mutex; /* protects buffers and mainqueue */
spinlock_t irqlock; /* protects irqqueue */
struct list_head mainqueue;
struct list_head irqqueue;
};
extern void uvc_queue_init(struct uvc_video_queue *queue,
enum v4l2_buf_type type);
extern int uvc_alloc_buffers(struct uvc_video_queue *queue,
unsigned int nbuffers, unsigned int buflength);
extern int uvc_free_buffers(struct uvc_video_queue *queue);
extern int uvc_query_buffer(struct uvc_video_queue *queue,
struct v4l2_buffer *v4l2_buf);
extern int uvc_queue_buffer(struct uvc_video_queue *queue,
struct v4l2_buffer *v4l2_buf);
extern int uvc_dequeue_buffer(struct uvc_video_queue *queue,
struct v4l2_buffer *v4l2_buf, int nonblocking);
extern int uvc_queue_enable(struct uvc_video_queue *queue, int enable);
extern void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect);
extern struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
struct uvc_buffer *buf);
extern unsigned int uvc_queue_poll(struct uvc_video_queue *queue,
struct file *file, poll_table *wait);
extern int uvc_queue_mmap(struct uvc_video_queue *queue,
struct vm_area_struct *vma);
static inline int uvc_queue_streaming(struct uvc_video_queue *queue)
{
return queue->flags & UVC_QUEUE_STREAMING;
}
extern struct uvc_buffer *uvc_queue_head(struct uvc_video_queue *queue);
#endif /* __KERNEL__ */
#endif /* _UVC_QUEUE_H_ */

374
drivers/usb/gadget/uvc_v4l2.c Normal file
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/*
* uvc_v4l2.c -- USB Video Class Gadget driver
*
* Copyright (C) 2009-2010
* Laurent Pinchart (laurent.pinchart@ideasonboard.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.
*
*/
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/version.h>
#include <linux/videodev2.h>
#include <linux/vmalloc.h>
#include <linux/wait.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-event.h>
#include <media/v4l2-ioctl.h>
#include "uvc.h"
#include "uvc_queue.h"
/* --------------------------------------------------------------------------
* Requests handling
*/
static int
uvc_send_response(struct uvc_device *uvc, struct uvc_request_data *data)
{
struct usb_composite_dev *cdev = uvc->func.config->cdev;
struct usb_request *req = uvc->control_req;
if (data->length < 0)
return usb_ep_set_halt(cdev->gadget->ep0);
req->length = min(uvc->event_length, data->length);
req->zero = data->length < uvc->event_length;
req->dma = DMA_ADDR_INVALID;
memcpy(req->buf, data->data, data->length);
return usb_ep_queue(cdev->gadget->ep0, req, GFP_KERNEL);
}
/* --------------------------------------------------------------------------
* V4L2
*/
struct uvc_format
{
u8 bpp;
u32 fcc;
};
static struct uvc_format uvc_formats[] = {
{ 16, V4L2_PIX_FMT_YUYV },
{ 0, V4L2_PIX_FMT_MJPEG },
};
static int
uvc_v4l2_get_format(struct uvc_video *video, struct v4l2_format *fmt)
{
fmt->fmt.pix.pixelformat = video->fcc;
fmt->fmt.pix.width = video->width;
fmt->fmt.pix.height = video->height;
fmt->fmt.pix.field = V4L2_FIELD_NONE;
fmt->fmt.pix.bytesperline = video->bpp * video->width / 8;
fmt->fmt.pix.sizeimage = video->imagesize;
fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
fmt->fmt.pix.priv = 0;
return 0;
}
static int
uvc_v4l2_set_format(struct uvc_video *video, struct v4l2_format *fmt)
{
struct uvc_format *format;
unsigned int imagesize;
unsigned int bpl;
unsigned int i;
for (i = 0; i < ARRAY_SIZE(uvc_formats); ++i) {
format = &uvc_formats[i];
if (format->fcc == fmt->fmt.pix.pixelformat)
break;
}
if (format == NULL || format->fcc != fmt->fmt.pix.pixelformat) {
printk(KERN_INFO "Unsupported format 0x%08x.\n",
fmt->fmt.pix.pixelformat);
return -EINVAL;
}
bpl = format->bpp * fmt->fmt.pix.width / 8;
imagesize = bpl ? bpl * fmt->fmt.pix.height : fmt->fmt.pix.sizeimage;
video->fcc = format->fcc;
video->bpp = format->bpp;
video->width = fmt->fmt.pix.width;
video->height = fmt->fmt.pix.height;
video->imagesize = imagesize;
fmt->fmt.pix.field = V4L2_FIELD_NONE;
fmt->fmt.pix.bytesperline = bpl;
fmt->fmt.pix.sizeimage = imagesize;
fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
fmt->fmt.pix.priv = 0;
return 0;
}
static int
uvc_v4l2_open(struct file *file)
{
struct video_device *vdev = video_devdata(file);
struct uvc_device *uvc = video_get_drvdata(vdev);
struct uvc_file_handle *handle;
int ret;
handle = kzalloc(sizeof(*handle), GFP_KERNEL);
if (handle == NULL)
return -ENOMEM;
ret = v4l2_fh_init(&handle->vfh, vdev);
if (ret < 0)
goto error;
ret = v4l2_event_init(&handle->vfh);
if (ret < 0)
goto error;
ret = v4l2_event_alloc(&handle->vfh, 8);
if (ret < 0)
goto error;
v4l2_fh_add(&handle->vfh);
handle->device = &uvc->video;
file->private_data = &handle->vfh;
uvc_function_connect(uvc);
return 0;
error:
v4l2_fh_exit(&handle->vfh);
return ret;
}
static int
uvc_v4l2_release(struct file *file)
{
struct video_device *vdev = video_devdata(file);
struct uvc_device *uvc = video_get_drvdata(vdev);
struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
struct uvc_video *video = handle->device;
uvc_function_disconnect(uvc);
uvc_video_enable(video, 0);
mutex_lock(&video->queue.mutex);
if (uvc_free_buffers(&video->queue) < 0)
printk(KERN_ERR "uvc_v4l2_release: Unable to free "
"buffers.\n");
mutex_unlock(&video->queue.mutex);
file->private_data = NULL;
v4l2_fh_del(&handle->vfh);
v4l2_fh_exit(&handle->vfh);
kfree(handle);
return 0;
}
static long
uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
{
struct video_device *vdev = video_devdata(file);
struct uvc_device *uvc = video_get_drvdata(vdev);
struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
struct usb_composite_dev *cdev = uvc->func.config->cdev;
struct uvc_video *video = &uvc->video;
int ret = 0;
switch (cmd) {
/* Query capabilities */
case VIDIOC_QUERYCAP:
{
struct v4l2_capability *cap = arg;
memset(cap, 0, sizeof *cap);
strncpy(cap->driver, "g_uvc", sizeof(cap->driver));
strncpy(cap->card, cdev->gadget->name, sizeof(cap->card));
strncpy(cap->bus_info, dev_name(&cdev->gadget->dev),
sizeof cap->bus_info);
cap->version = DRIVER_VERSION_NUMBER;
cap->capabilities = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
break;
}
/* Get & Set format */
case VIDIOC_G_FMT:
{
struct v4l2_format *fmt = arg;
if (fmt->type != video->queue.type)
return -EINVAL;
return uvc_v4l2_get_format(video, fmt);
}
case VIDIOC_S_FMT:
{
struct v4l2_format *fmt = arg;
if (fmt->type != video->queue.type)
return -EINVAL;
return uvc_v4l2_set_format(video, fmt);
}
/* Buffers & streaming */
case VIDIOC_REQBUFS:
{
struct v4l2_requestbuffers *rb = arg;
if (rb->type != video->queue.type ||
rb->memory != V4L2_MEMORY_MMAP)
return -EINVAL;
ret = uvc_alloc_buffers(&video->queue, rb->count,
video->imagesize);
if (ret < 0)
return ret;
rb->count = ret;
ret = 0;
break;
}
case VIDIOC_QUERYBUF:
{
struct v4l2_buffer *buf = arg;
if (buf->type != video->queue.type)
return -EINVAL;
return uvc_query_buffer(&video->queue, buf);
}
case VIDIOC_QBUF:
if ((ret = uvc_queue_buffer(&video->queue, arg)) < 0)
return ret;
return uvc_video_pump(video);
case VIDIOC_DQBUF:
return uvc_dequeue_buffer(&video->queue, arg,
file->f_flags & O_NONBLOCK);
case VIDIOC_STREAMON:
{
int *type = arg;
if (*type != video->queue.type)
return -EINVAL;
return uvc_video_enable(video, 1);
}
case VIDIOC_STREAMOFF:
{
int *type = arg;
if (*type != video->queue.type)
return -EINVAL;
return uvc_video_enable(video, 0);
}
/* Events */
case VIDIOC_DQEVENT:
{
struct v4l2_event *event = arg;
ret = v4l2_event_dequeue(&handle->vfh, event,
file->f_flags & O_NONBLOCK);
if (ret == 0 && event->type == UVC_EVENT_SETUP) {
struct uvc_event *uvc_event = (void *)&event->u.data;
/* Tell the complete callback to generate an event for
* the next request that will be enqueued by
* uvc_event_write.
*/
uvc->event_setup_out =
!(uvc_event->req.bRequestType & USB_DIR_IN);
uvc->event_length = uvc_event->req.wLength;
}
return ret;
}
case VIDIOC_SUBSCRIBE_EVENT:
{
struct v4l2_event_subscription *sub = arg;
if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
return -EINVAL;
return v4l2_event_subscribe(&handle->vfh, arg);
}
case VIDIOC_UNSUBSCRIBE_EVENT:
return v4l2_event_unsubscribe(&handle->vfh, arg);
case UVCIOC_SEND_RESPONSE:
ret = uvc_send_response(uvc, arg);
break;
default:
return -ENOIOCTLCMD;
}
return ret;
}
static long
uvc_v4l2_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
return video_usercopy(file, cmd, arg, uvc_v4l2_do_ioctl);
}
static int
uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
{
struct video_device *vdev = video_devdata(file);
struct uvc_device *uvc = video_get_drvdata(vdev);
return uvc_queue_mmap(&uvc->video.queue, vma);
}
static unsigned int
uvc_v4l2_poll(struct file *file, poll_table *wait)
{
struct video_device *vdev = video_devdata(file);
struct uvc_device *uvc = video_get_drvdata(vdev);
struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
unsigned int mask = 0;
poll_wait(file, &handle->vfh.events->wait, wait);
if (v4l2_event_pending(&handle->vfh))
mask |= POLLPRI;
mask |= uvc_queue_poll(&uvc->video.queue, file, wait);
return mask;
}
struct v4l2_file_operations uvc_v4l2_fops = {
.owner = THIS_MODULE,
.open = uvc_v4l2_open,
.release = uvc_v4l2_release,
.ioctl = uvc_v4l2_ioctl,
.mmap = uvc_v4l2_mmap,
.poll = uvc_v4l2_poll,
};

386
drivers/usb/gadget/uvc_video.c Normal file
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@ -0,0 +1,386 @@
/*
* uvc_video.c -- USB Video Class Gadget driver
*
* Copyright (C) 2009-2010
* Laurent Pinchart (laurent.pinchart@ideasonboard.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.
*
*/
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <media/v4l2-dev.h>
#include "uvc.h"
#include "uvc_queue.h"
/* --------------------------------------------------------------------------
* Video codecs
*/
static int
uvc_video_encode_header(struct uvc_video *video, struct uvc_buffer *buf,
u8 *data, int len)
{
data[0] = 2;
data[1] = UVC_STREAM_EOH | video->fid;
if (buf->buf.bytesused - video->queue.buf_used <= len - 2)
data[1] |= UVC_STREAM_EOF;
return 2;
}
static int
uvc_video_encode_data(struct uvc_video *video, struct uvc_buffer *buf,
u8 *data, int len)
{
struct uvc_video_queue *queue = &video->queue;
unsigned int nbytes;
void *mem;
/* Copy video data to the USB buffer. */
mem = queue->mem + buf->buf.m.offset + queue->buf_used;
nbytes = min((unsigned int)len, buf->buf.bytesused - queue->buf_used);
memcpy(data, mem, nbytes);
queue->buf_used += nbytes;
return nbytes;
}
static void
uvc_video_encode_bulk(struct usb_request *req, struct uvc_video *video,
struct uvc_buffer *buf)
{
void *mem = req->buf;
int len = video->req_size;
int ret;
/* Add a header at the beginning of the payload. */
if (video->payload_size == 0) {
ret = uvc_video_encode_header(video, buf, mem, len);
video->payload_size += ret;
mem += ret;
len -= ret;
}
/* Process video data. */
len = min((int)(video->max_payload_size - video->payload_size), len);
ret = uvc_video_encode_data(video, buf, mem, len);
video->payload_size += ret;
len -= ret;
req->length = video->req_size - len;
req->zero = video->payload_size == video->max_payload_size;
if (buf->buf.bytesused == video->queue.buf_used) {
video->queue.buf_used = 0;
buf->state = UVC_BUF_STATE_DONE;
uvc_queue_next_buffer(&video->queue, buf);
video->fid ^= UVC_STREAM_FID;
video->payload_size = 0;
}
if (video->payload_size == video->max_payload_size ||
buf->buf.bytesused == video->queue.buf_used)
video->payload_size = 0;
}
static void
uvc_video_encode_isoc(struct usb_request *req, struct uvc_video *video,
struct uvc_buffer *buf)
{
void *mem = req->buf;
int len = video->req_size;
int ret;
/* Add the header. */
ret = uvc_video_encode_header(video, buf, mem, len);
mem += ret;
len -= ret;
/* Process video data. */
ret = uvc_video_encode_data(video, buf, mem, len);
len -= ret;
req->length = video->req_size - len;
if (buf->buf.bytesused == video->queue.buf_used) {
video->queue.buf_used = 0;
buf->state = UVC_BUF_STATE_DONE;
uvc_queue_next_buffer(&video->queue, buf);
video->fid ^= UVC_STREAM_FID;
}
}
/* --------------------------------------------------------------------------
* Request handling
*/
/*
* I somehow feel that synchronisation won't be easy to achieve here. We have
* three events that control USB requests submission:
*
* - USB request completion: the completion handler will resubmit the request
* if a video buffer is available.
*
* - USB interface setting selection: in response to a SET_INTERFACE request,
* the handler will start streaming if a video buffer is available and if
* video is not currently streaming.
*
* - V4L2 buffer queueing: the driver will start streaming if video is not
* currently streaming.
*
* Race conditions between those 3 events might lead to deadlocks or other
* nasty side effects.
*
* The "video currently streaming" condition can't be detected by the irqqueue
* being empty, as a request can still be in flight. A separate "queue paused"
* flag is thus needed.
*
* The paused flag will be set when we try to retrieve the irqqueue head if the
* queue is empty, and cleared when we queue a buffer.
*
* The USB request completion handler will get the buffer at the irqqueue head
* under protection of the queue spinlock. If the queue is empty, the streaming
* paused flag will be set. Right after releasing the spinlock a userspace
* application can queue a buffer. The flag will then cleared, and the ioctl
* handler will restart the video stream.
*/
static void
uvc_video_complete(struct usb_ep *ep, struct usb_request *req)
{
struct uvc_video *video = req->context;
struct uvc_buffer *buf;
unsigned long flags;
int ret;
switch (req->status) {
case 0:
break;
case -ESHUTDOWN:
printk(KERN_INFO "VS request cancelled.\n");
goto requeue;
default:
printk(KERN_INFO "VS request completed with status %d.\n",
req->status);
goto requeue;
}
spin_lock_irqsave(&video->queue.irqlock, flags);
buf = uvc_queue_head(&video->queue);
if (buf == NULL) {
spin_unlock_irqrestore(&video->queue.irqlock, flags);
goto requeue;
}
video->encode(req, video, buf);
if ((ret = usb_ep_queue(ep, req, GFP_ATOMIC)) < 0) {
printk(KERN_INFO "Failed to queue request (%d).\n", ret);
usb_ep_set_halt(ep);
spin_unlock_irqrestore(&video->queue.irqlock, flags);
goto requeue;
}
spin_unlock_irqrestore(&video->queue.irqlock, flags);
return;
requeue:
spin_lock_irqsave(&video->req_lock, flags);
list_add_tail(&req->list, &video->req_free);
spin_unlock_irqrestore(&video->req_lock, flags);
}
static int
uvc_video_free_requests(struct uvc_video *video)
{
unsigned int i;
for (i = 0; i < UVC_NUM_REQUESTS; ++i) {
if (video->req[i]) {
usb_ep_free_request(video->ep, video->req[i]);
video->req[i] = NULL;
}
if (video->req_buffer[i]) {
kfree(video->req_buffer[i]);
video->req_buffer[i] = NULL;
}
}
INIT_LIST_HEAD(&video->req_free);
video->req_size = 0;
return 0;
}
static int
uvc_video_alloc_requests(struct uvc_video *video)
{
unsigned int i;
int ret = -ENOMEM;
BUG_ON(video->req_size);
for (i = 0; i < UVC_NUM_REQUESTS; ++i) {
video->req_buffer[i] = kmalloc(video->ep->maxpacket, GFP_KERNEL);
if (video->req_buffer[i] == NULL)
goto error;
video->req[i] = usb_ep_alloc_request(video->ep, GFP_KERNEL);
if (video->req[i] == NULL)
goto error;
video->req[i]->buf = video->req_buffer[i];
video->req[i]->length = 0;
video->req[i]->dma = DMA_ADDR_INVALID;
video->req[i]->complete = uvc_video_complete;
video->req[i]->context = video;
list_add_tail(&video->req[i]->list, &video->req_free);
}
video->req_size = video->ep->maxpacket;
return 0;
error:
uvc_video_free_requests(video);
return ret;
}
/* --------------------------------------------------------------------------
* Video streaming
*/
/*
* uvc_video_pump - Pump video data into the USB requests
*
* This function fills the available USB requests (listed in req_free) with
* video data from the queued buffers.
*/
int
uvc_video_pump(struct uvc_video *video)
{
struct usb_request *req;
struct uvc_buffer *buf;
unsigned long flags;
int ret;
/* FIXME TODO Race between uvc_video_pump and requests completion
* handler ???
*/
while (1) {
/* Retrieve the first available USB request, protected by the
* request lock.
*/
spin_lock_irqsave(&video->req_lock, flags);
if (list_empty(&video->req_free)) {
spin_unlock_irqrestore(&video->req_lock, flags);
return 0;
}
req = list_first_entry(&video->req_free, struct usb_request,
list);
list_del(&req->list);
spin_unlock_irqrestore(&video->req_lock, flags);
/* Retrieve the first available video buffer and fill the
* request, protected by the video queue irqlock.
*/
spin_lock_irqsave(&video->queue.irqlock, flags);
buf = uvc_queue_head(&video->queue);
if (buf == NULL) {
spin_unlock_irqrestore(&video->queue.irqlock, flags);
break;
}
video->encode(req, video, buf);
/* Queue the USB request */
if ((ret = usb_ep_queue(video->ep, req, GFP_KERNEL)) < 0) {
printk(KERN_INFO "Failed to queue request (%d)\n", ret);
usb_ep_set_halt(video->ep);
spin_unlock_irqrestore(&video->queue.irqlock, flags);
break;
}
spin_unlock_irqrestore(&video->queue.irqlock, flags);
}
spin_lock_irqsave(&video->req_lock, flags);
list_add_tail(&req->list, &video->req_free);
spin_unlock_irqrestore(&video->req_lock, flags);
return 0;
}
/*
* Enable or disable the video stream.
*/
int
uvc_video_enable(struct uvc_video *video, int enable)
{
unsigned int i;
int ret;
if (video->ep == NULL) {
printk(KERN_INFO "Video enable failed, device is "
"uninitialized.\n");
return -ENODEV;
}
if (!enable) {
for (i = 0; i < UVC_NUM_REQUESTS; ++i)
usb_ep_dequeue(video->ep, video->req[i]);
uvc_video_free_requests(video);
uvc_queue_enable(&video->queue, 0);
return 0;
}
if ((ret = uvc_queue_enable(&video->queue, 1)) < 0)
return ret;
if ((ret = uvc_video_alloc_requests(video)) < 0)
return ret;
if (video->max_payload_size) {
video->encode = uvc_video_encode_bulk;
video->payload_size = 0;
} else
video->encode = uvc_video_encode_isoc;
return uvc_video_pump(video);
}
/*
* Initialize the UVC video stream.
*/
int
uvc_video_init(struct uvc_video *video)
{
INIT_LIST_HEAD(&video->req_free);
spin_lock_init(&video->req_lock);
video->fcc = V4L2_PIX_FMT_YUYV;
video->bpp = 16;
video->width = 320;
video->height = 240;
video->imagesize = 320 * 240 * 2;
/* Initialize the video buffers queue. */
uvc_queue_init(&video->queue, V4L2_BUF_TYPE_VIDEO_OUTPUT);
return 0;
}