diff options
Diffstat (limited to 'drivers/media/video/uvc/uvc_queue.c')
| -rw-r--r-- | drivers/media/video/uvc/uvc_queue.c | 31 |
1 files changed, 15 insertions, 16 deletions
diff --git a/drivers/media/video/uvc/uvc_queue.c b/drivers/media/video/uvc/uvc_queue.c index 42546342e97..0155752e4a5 100644 --- a/drivers/media/video/uvc/uvc_queue.c +++ b/drivers/media/video/uvc/uvc_queue.c @@ -1,7 +1,7 @@ /* * uvc_queue.c -- USB Video Class driver - Buffers management * - * Copyright (C) 2005-2008 + * Copyright (C) 2005-2009 * Laurent Pinchart (laurent.pinchart@skynet.be) * * This program is free software; you can redistribute it and/or modify @@ -12,7 +12,6 @@ */ #include <linux/kernel.h> -#include <linux/version.h> #include <linux/mm.h> #include <linux/list.h> #include <linux/module.h> @@ -37,22 +36,22 @@ * to user space will return -EBUSY. * * Video buffers are managed using two queues. However, unlike most USB video - * drivers which use an in queue and an out queue, we use a main queue which - * holds all queued buffers (both 'empty' and 'done' buffers), and an irq - * queue which holds empty buffers. This design (copied from video-buf) - * minimizes locking in interrupt, as only one queue is shared between - * interrupt and user contexts. + * 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 which modify the irq buffers queue + * 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 latert is protected by the irq + * 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 @@ -60,7 +59,7 @@ * 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 wake its wait queue. + * 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. @@ -91,8 +90,8 @@ void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type) /* * Allocate the video buffers. * - * Pages are reserved to make sure they will not be swaped, as they will be - * filled in URB completion handler. + * 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. */ @@ -210,8 +209,8 @@ int uvc_query_buffer(struct uvc_video_queue *queue, __uvc_query_buffer(&queue->buffer[v4l2_buf->index], v4l2_buf); done: - mutex_unlock(&queue->mutex); - return ret; + mutex_unlock(&queue->mutex); + return ret; } /* @@ -236,7 +235,7 @@ int uvc_queue_buffer(struct uvc_video_queue *queue, } mutex_lock(&queue->mutex); - if (v4l2_buf->index >= queue->count) { + if (v4l2_buf->index >= queue->count) { uvc_trace(UVC_TRACE_CAPTURE, "[E] Out of range index.\n"); ret = -EINVAL; goto done; @@ -429,7 +428,7 @@ done: * Cancel the video buffers queue. * * Cancelling the queue marks all buffers on the irq queue as erroneous, - * wakes them up and remove them from the queue. + * 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. |