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[RFT PATCH v3 4/6] uvcvideo: queue: Simplify spin-lock usage




Both uvc_start_streaming(), and uvc_stop_streaming() are called from
userspace context. As such, they do not need to save the IRQ state, and
can use spin_lock_irq() and spin_unlock_irq() respectively.

Signed-off-by: Kieran Bingham <kieran.bingham@xxxxxxxxxxxxxxxx>
---
 drivers/media/usb/uvc/uvc_queue.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_queue.c b/drivers/media/usb/uvc/uvc_queue.c
index 4a581d631525..ddac4d89a291 100644
--- a/drivers/media/usb/uvc/uvc_queue.c
+++ b/drivers/media/usb/uvc/uvc_queue.c
@@ -158,7 +158,6 @@ static int uvc_start_streaming(struct vb2_queue *vq, unsigned int count)
 {
 	struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
 	struct uvc_streaming *stream = uvc_queue_to_stream(queue);
-	unsigned long flags;
 	int ret;
 
 	queue->buf_used = 0;
@@ -167,9 +166,9 @@ static int uvc_start_streaming(struct vb2_queue *vq, unsigned int count)
 	if (ret == 0)
 		return 0;
 
-	spin_lock_irqsave(&queue->irqlock, flags);
+	spin_lock_irq(&queue->irqlock);
 	uvc_queue_return_buffers(queue, UVC_BUF_STATE_QUEUED);
-	spin_unlock_irqrestore(&queue->irqlock, flags);
+	spin_unlock_irq(&queue->irqlock);
 
 	return ret;
 }
@@ -178,13 +177,12 @@ static void uvc_stop_streaming(struct vb2_queue *vq)
 {
 	struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
 	struct uvc_streaming *stream = uvc_queue_to_stream(queue);
-	unsigned long flags;
 
 	uvc_video_enable(stream, 0);
 
-	spin_lock_irqsave(&queue->irqlock, flags);
+	spin_lock_irq(&queue->irqlock);
 	uvc_queue_return_buffers(queue, UVC_BUF_STATE_ERROR);
-	spin_unlock_irqrestore(&queue->irqlock, flags);
+	spin_unlock_irq(&queue->irqlock);
 }
 
 static const struct vb2_ops uvc_queue_qops = {
-- 
git-series 0.9.1