usb data out 过程分析

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); } } /* 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; /* * s3c2410_udc_done */ static void s3c2410_udc_done(struct s3c2410_ep *ep, struct s3c2410_request *req, int status) { unsigned halted = ep->halted; list_del_init(&req->queue); if (likely(req->req.status == -EINPROGRESS)) req->req.status = status; else status = req->req.status; ep->halted = 1; usb_gadget_giveback_request(&ep->ep, &req->req); ep->halted = halted; } static void s3c2410_udc_nuke(struct s3c2410_udc *udc, struct s3c2410_ep *ep, int status) { /* Sanity check */ if (&ep->queue == NULL) return; while (!list_empty(&ep->queue)) { struct s3c2410_request *req; req = list_entry(ep->queue.next, struct s3c2410_request, queue); s3c2410_udc_done(ep, req, status); } } /** * usb_gadget_giveback_request - give the request back to the gadget layer * Context: in_interrupt() * * This is called by device controller drivers in order to return the * completed request back to the gadget layer. */ void usb_gadget_giveback_request(struct usb_ep *ep, struct usb_request *req) { if (likely(req->status == 0)) usb_led_activity(USB_LED_EVENT_GADGET); trace_usb_gadget_giveback_request(ep, req, 0); req->complete(ep, req); } EXPORT_SYMBOL_GPL(usb_gadget_giveback_request); /* Save index */ idx = udc_read(S3C2410_UDC_INDEX_REG); /* Read status registers */ usb_status = udc_read(S3C2410_UDC_USB_INT_REG); usbd_status = udc_read(S3C2410_UDC_EP_INT_REG); pwr_reg = udc_read(S3C2410_UDC_PWR_REG); udc_writeb(base_addr, S3C2410_UDC_INDEX_EP0, S3C2410_UDC_INDEX_REG); ep0csr = udc_read(S3C2410_UDC_IN_CSR1_REG); if (usbd_status & S3C2410_UDC_INT_EP0) { dprintk(DEBUG_VERBOSE, "USB ep0 irq\n"); /* Clear the interrupt bit by setting it to 1 */ udc_write(S3C2410_UDC_INT_EP0, S3C2410_UDC_EP_INT_REG); s3c2410_udc_handle_ep0(dev); } s3c2410_udc_irq s3c2410_udc_handle_ep0 s3c2410_udc_handle_ep0_idle s3c2410_udc_nuke(dev, ep, -EPROTO); s3c2410_udc_done(ep, req, status); usb_gadget_giveback_request(&ep->ep, &req->req); req->complete(ep, req); uvc_function_ep0_complete 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); case UVC_EVENT_DATA: ret = uvc_events_process_data(dev, &uvc_event->data); if (ret < 0) break; return; if (dev->control == UVC_VS_COMMIT_CONTROL) { if (uvc_video_get_uvc_process(dev->video_id)) return 0; dev->fcc = format->fcc; dev->width = frame->width; dev->height = frame->height; dev->fps = 10000000 / target->dwFrameInterval; /* * Try to set the default format at the V4L2 video capture * device as requested by the user. */ CLEAR(fmt); fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; fmt.fmt.pix.field = V4L2_FIELD_ANY; fmt.fmt.pix.width = frame->width; fmt.fmt.pix.height = frame->height; fmt.fmt.pix.pixelformat = format->fcc; switch (format->fcc) { case V4L2_PIX_FMT_YUYV: fmt.fmt.pix.sizeimage = (fmt.fmt.pix.width * fmt.fmt.pix.height * 2); break; case V4L2_PIX_FMT_MJPEG: case V4L2_PIX_FMT_H264: fmt.fmt.pix.sizeimage = dev->imgsize; break; } uvc_set_user_resolution(fmt.fmt.pix.width, fmt.fmt.pix.height, dev->video_id); uvc_set_user_fcc(fmt.fmt.pix.pixelformat, dev->video_id); if (uvc_buffer_init(dev->video_id)) goto err; /* * As per the new commit command received from the UVC host * change the current format selection at both UVC and V4L2 * sides. */ ret = uvc_video_set_format(dev); if (ret < 0) goto err; if (!dev->run_standalone) { /* UVC - V4L2 integrated path. */ ret = v4l2_set_format(dev->vdev, &fmt); if (ret < 0) goto err; } if (dev->bulk) { ret = uvc_handle_streamon_event(dev); if (ret < 0) goto err; } }