static int
uvc_video_pump(struct uvc_video *video)
{
struct usb_request *req;
struct uvc_buffer *buf;
unsigned long flags;
int ret;
/*
*/
while (1) {
/*
*/
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);
/*
*/
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);
/* */
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;
}
/*
* 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.
*/
static 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;
}
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);
}