new file mode 100644
@@ -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");
+
new file mode 100644
@@ -0,0 +1,376 @@
+/*
+ * 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_ */
+
new file mode 100644
@@ -0,0 +1,241 @@
+/*
+ * 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_ */
+
new file mode 100644
@@ -0,0 +1,583 @@
+/*
+ * 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;
+}
+
new file mode 100644
@@ -0,0 +1,89 @@
+#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_ */
+
new file mode 100644
@@ -0,0 +1,374 @@
+/*
+ * 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,
+};
+
new file mode 100644
@@ -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;
+}
+