diff options
| -rw-r--r-- | drivers/media/video/gspca/gspca.c | 112 | ||||
| -rw-r--r-- | drivers/media/video/gspca/gspca.h | 1 |
2 files changed, 58 insertions, 55 deletions
diff --git a/drivers/media/video/gspca/gspca.c b/drivers/media/video/gspca/gspca.c index 74626b6a9eb4..64ecf669d655 100644 --- a/drivers/media/video/gspca/gspca.c +++ b/drivers/media/video/gspca/gspca.c @@ -1831,33 +1831,77 @@ out: return ret; } +static int frame_ready_nolock(struct gspca_dev *gspca_dev, struct file *file, + enum v4l2_memory memory) +{ + if (!gspca_dev->present) + return -ENODEV; + if (gspca_dev->capt_file != file || gspca_dev->memory != memory || + !gspca_dev->streaming) + return -EINVAL; + + /* check if a frame is ready */ + return gspca_dev->fr_o != atomic_read(&gspca_dev->fr_i); +} + +static int frame_ready(struct gspca_dev *gspca_dev, struct file *file, + enum v4l2_memory memory) +{ + int ret; + + if (mutex_lock_interruptible(&gspca_dev->queue_lock)) + return -ERESTARTSYS; + ret = frame_ready_nolock(gspca_dev, file, memory); + mutex_unlock(&gspca_dev->queue_lock); + return ret; +} + /* - * wait for a video frame + * dequeue a video buffer * - * If a frame is ready, its index is returned. + * If nonblock_ing is false, block until a buffer is available. */ -static int frame_wait(struct gspca_dev *gspca_dev, - int nonblock_ing) +static int vidioc_dqbuf(struct file *file, void *priv, + struct v4l2_buffer *v4l2_buf) { - int i, ret; + struct gspca_dev *gspca_dev = priv; + struct gspca_frame *frame; + int i, j, ret; - /* check if a frame is ready */ - i = gspca_dev->fr_o; - if (i == atomic_read(&gspca_dev->fr_i)) { - if (nonblock_ing) + PDEBUG(D_FRAM, "dqbuf"); + + if (mutex_lock_interruptible(&gspca_dev->queue_lock)) + return -ERESTARTSYS; + + for (;;) { + ret = frame_ready_nolock(gspca_dev, file, v4l2_buf->memory); + if (ret < 0) + goto out; + if (ret > 0) + break; + + mutex_unlock(&gspca_dev->queue_lock); + + if (file->f_flags & O_NONBLOCK) return -EAGAIN; /* wait till a frame is ready */ ret = wait_event_interruptible_timeout(gspca_dev->wq, - i != atomic_read(&gspca_dev->fr_i) || - !gspca_dev->streaming || !gspca_dev->present, + frame_ready(gspca_dev, file, v4l2_buf->memory), msecs_to_jiffies(3000)); if (ret < 0) return ret; - if (ret == 0 || !gspca_dev->streaming || !gspca_dev->present) + if (ret == 0) return -EIO; + + if (mutex_lock_interruptible(&gspca_dev->queue_lock)) + return -ERESTARTSYS; } + i = gspca_dev->fr_o; + j = gspca_dev->fr_queue[i]; + frame = &gspca_dev->frame[j]; + gspca_dev->fr_o = (i + 1) % GSPCA_MAX_FRAMES; if (gspca_dev->sd_desc->dq_callback) { @@ -1867,46 +1911,7 @@ static int frame_wait(struct gspca_dev *gspca_dev, gspca_dev->sd_desc->dq_callback(gspca_dev); mutex_unlock(&gspca_dev->usb_lock); } - return gspca_dev->fr_queue[i]; -} - -/* - * dequeue a video buffer - * - * If nonblock_ing is false, block until a buffer is available. - */ -static int vidioc_dqbuf(struct file *file, void *priv, - struct v4l2_buffer *v4l2_buf) -{ - struct gspca_dev *gspca_dev = priv; - struct gspca_frame *frame; - int i, ret; - - PDEBUG(D_FRAM, "dqbuf"); - if (v4l2_buf->memory != gspca_dev->memory) - return -EINVAL; - if (!gspca_dev->present) - return -ENODEV; - - /* if not streaming, be sure the application will not loop forever */ - if (!(file->f_flags & O_NONBLOCK) - && !gspca_dev->streaming && gspca_dev->users == 1) - return -EINVAL; - - /* only the capturing file may dequeue */ - if (gspca_dev->capt_file != file) - return -EINVAL; - - /* only one dequeue / read at a time */ - if (mutex_lock_interruptible(&gspca_dev->read_lock)) - return -ERESTARTSYS; - - ret = frame_wait(gspca_dev, file->f_flags & O_NONBLOCK); - if (ret < 0) - goto out; - i = ret; /* frame index */ - frame = &gspca_dev->frame[i]; if (gspca_dev->memory == V4L2_MEMORY_USERPTR) { if (copy_to_user((__u8 __user *) frame->v4l2_buf.m.userptr, frame->data, @@ -1919,10 +1924,10 @@ static int vidioc_dqbuf(struct file *file, void *priv, } frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_DONE; memcpy(v4l2_buf, &frame->v4l2_buf, sizeof *v4l2_buf); - PDEBUG(D_FRAM, "dqbuf %d", i); + PDEBUG(D_FRAM, "dqbuf %d", j); ret = 0; out: - mutex_unlock(&gspca_dev->read_lock); + mutex_unlock(&gspca_dev->queue_lock); return ret; } @@ -2270,7 +2275,6 @@ int gspca_dev_probe2(struct usb_interface *intf, goto out; mutex_init(&gspca_dev->usb_lock); - mutex_init(&gspca_dev->read_lock); mutex_init(&gspca_dev->queue_lock); init_waitqueue_head(&gspca_dev->wq); diff --git a/drivers/media/video/gspca/gspca.h b/drivers/media/video/gspca/gspca.h index 97b77a26a2eb..a2a1a6aa0606 100644 --- a/drivers/media/video/gspca/gspca.h +++ b/drivers/media/video/gspca/gspca.h @@ -205,7 +205,6 @@ struct gspca_dev { wait_queue_head_t wq; /* wait queue */ struct mutex usb_lock; /* usb exchange protection */ - struct mutex read_lock; /* read protection */ struct mutex queue_lock; /* ISOC queue protection */ int usb_err; /* USB error - protected by usb_lock */ u16 pkt_size; /* ISOC packet size */ |