The stream mutex protects access to the struct uvc_streaming ctrl,
cur_format and cur_frame fields as well as to the hardware probe
control. Lock it appropriately.
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
drivers/media/video/uvc/uvc_v4l2.c | 76 +++++++++++++++++++++++++----------
drivers/media/video/uvc/uvc_video.c | 3 -
drivers/media/video/uvc/uvcvideo.h | 4 +-
3 files changed, 57 insertions(+), 26 deletions(-)
diff --git a/drivers/media/video/uvc/uvc_v4l2.c b/drivers/media/video/uvc/uvc_v4l2.c
index 07dd235..b4615e2 100644
--- a/drivers/media/video/uvc/uvc_v4l2.c
+++ b/drivers/media/video/uvc/uvc_v4l2.c
@@ -226,12 +226,14 @@ static int uvc_v4l2_try_format(struct uvc_streaming *stream,
* developers test their webcams with the Linux driver as well as with
* the Windows driver).
*/
+ mutex_lock(&stream->mutex);
if (stream->dev->quirks & UVC_QUIRK_PROBE_EXTRAFIELDS)
probe->dwMaxVideoFrameSize =
stream->ctrl.dwMaxVideoFrameSize;
/* Probe the device. */
ret = uvc_probe_video(stream, probe);
+ mutex_unlock(&stream->mutex);
if (ret < 0)
goto done;
@@ -255,14 +257,21 @@ done:
static int uvc_v4l2_get_format(struct uvc_streaming *stream,
struct v4l2_format *fmt)
{
- struct uvc_format *format = stream->cur_format;
- struct uvc_frame *frame = stream->cur_frame;
+ struct uvc_format *format;
+ struct uvc_frame *frame;
+ int ret = 0;
if (fmt->type != stream->type)
return -EINVAL;
- if (format == NULL || frame == NULL)
- return -EINVAL;
+ mutex_lock(&stream->mutex);
+ format = stream->cur_format;
+ frame = stream->cur_frame;
+
+ if (format == NULL || frame == NULL) {
+ ret = -EINVAL;
+ goto done;
+ }
fmt->fmt.pix.pixelformat = format->fcc;
fmt->fmt.pix.width = frame->wWidth;
@@ -273,6 +282,8 @@ static int uvc_v4l2_get_format(struct uvc_streaming *stream,
fmt->fmt.pix.colorspace = format->colorspace;
fmt->fmt.pix.priv = 0;
+done:
+ mutex_unlock(&stream->mutex);
return 0;
}
@@ -287,18 +298,24 @@ static int uvc_v4l2_set_format(struct uvc_streaming *stream,
if (fmt->type != stream->type)
return -EINVAL;
- if (uvc_queue_allocated(&stream->queue))
- return -EBUSY;
-
ret = uvc_v4l2_try_format(stream, fmt, &probe, &format, &frame);
if (ret < 0)
return ret;
+ mutex_lock(&stream->mutex);
+
+ if (uvc_queue_allocated(&stream->queue)) {
+ ret = -EBUSY;
+ goto done;
+ }
+
memcpy(&stream->ctrl, &probe, sizeof probe);
stream->cur_format = format;
stream->cur_frame = frame;
- return 0;
+done:
+ mutex_unlock(&stream->mutex);
+ return ret;
}
static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream,
@@ -309,7 +326,10 @@ static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream,
if (parm->type != stream->type)
return -EINVAL;
+ mutex_lock(&stream->mutex);
numerator = stream->ctrl.dwFrameInterval;
+ mutex_unlock(&stream->mutex);
+
denominator = 10000000;
uvc_simplify_fraction(&numerator, &denominator, 8, 333);
@@ -336,7 +356,6 @@ static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream,
static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream,
struct v4l2_streamparm *parm)
{
- struct uvc_frame *frame = stream->cur_frame;
struct uvc_streaming_control probe;
struct v4l2_fract timeperframe;
uint32_t interval;
@@ -345,28 +364,36 @@ static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream,
if (parm->type != stream->type)
return -EINVAL;
- if (uvc_queue_streaming(&stream->queue))
- return -EBUSY;
-
if (parm->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
timeperframe = parm->parm.capture.timeperframe;
else
timeperframe = parm->parm.output.timeperframe;
- memcpy(&probe, &stream->ctrl, sizeof probe);
interval = uvc_fraction_to_interval(timeperframe.numerator,
timeperframe.denominator);
-
uvc_trace(UVC_TRACE_FORMAT, "Setting frame interval to %u/%u (%u).\n",
timeperframe.numerator, timeperframe.denominator, interval);
- probe.dwFrameInterval = uvc_try_frame_interval(frame, interval);
+
+ mutex_lock(&stream->mutex);
+
+ if (uvc_queue_streaming(&stream->queue)) {
+ mutex_unlock(&stream->mutex);
+ return -EBUSY;
+ }
+
+ memcpy(&probe, &stream->ctrl, sizeof probe);
+ probe.dwFrameInterval =
+ uvc_try_frame_interval(stream->cur_frame, interval);
/* Probe the device with the new settings. */
ret = uvc_probe_video(stream, &probe);
- if (ret < 0)
+ if (ret < 0) {
+ mutex_unlock(&stream->mutex);
return ret;
+ }
memcpy(&stream->ctrl, &probe, sizeof probe);
+ mutex_unlock(&stream->mutex);
/* Return the actual frame period. */
timeperframe.numerator = probe.dwFrameInterval;
@@ -869,15 +896,17 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
case VIDIOC_CROPCAP:
{
struct v4l2_cropcap *ccap = arg;
- struct uvc_frame *frame = stream->cur_frame;
if (ccap->type != stream->type)
return -EINVAL;
ccap->bounds.left = 0;
ccap->bounds.top = 0;
- ccap->bounds.width = frame->wWidth;
- ccap->bounds.height = frame->wHeight;
+
+ mutex_lock(&stream->mutex);
+ ccap->bounds.width = stream->cur_frame->wWidth;
+ ccap->bounds.height = stream->cur_frame->wHeight;
+ mutex_unlock(&stream->mutex);
ccap->defrect = ccap->bounds;
@@ -894,8 +923,6 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
case VIDIOC_REQBUFS:
{
struct v4l2_requestbuffers *rb = arg;
- unsigned int bufsize =
- stream->ctrl.dwMaxVideoFrameSize;
if (rb->type != stream->type ||
rb->memory != V4L2_MEMORY_MMAP)
@@ -904,7 +931,10 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
if ((ret = uvc_acquire_privileges(handle)) < 0)
return ret;
- ret = uvc_alloc_buffers(&stream->queue, rb->count, bufsize);
+ mutex_lock(&stream->mutex);
+ ret = uvc_alloc_buffers(&stream->queue, rb->count,
+ stream->ctrl.dwMaxVideoFrameSize);
+ mutex_unlock(&stream->mutex);
if (ret < 0)
return ret;
@@ -952,7 +982,9 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
if (!uvc_has_privileges(handle))
return -EBUSY;
+ mutex_lock(&stream->mutex);
ret = uvc_video_enable(stream, 1);
+ mutex_unlock(&stream->mutex);
if (ret < 0)
return ret;
break;
diff --git a/drivers/media/video/uvc/uvc_video.c b/drivers/media/video/uvc/uvc_video.c
index 5555f01..5673d67 100644
--- a/drivers/media/video/uvc/uvc_video.c
+++ b/drivers/media/video/uvc/uvc_video.c
@@ -293,8 +293,6 @@ int uvc_probe_video(struct uvc_streaming *stream,
unsigned int i;
int ret;
- mutex_lock(&stream->mutex);
-
/* Perform probing. The device should adjust the requested values
* according to its capabilities. However, some devices, namely the
* first generation UVC Logitech webcams, don't implement the Video
@@ -346,7 +344,6 @@ int uvc_probe_video(struct uvc_streaming *stream,
}
done:
- mutex_unlock(&stream->mutex);
return ret;
}
diff --git a/drivers/media/video/uvc/uvcvideo.h b/drivers/media/video/uvc/uvcvideo.h
index ea893bc..45f01e7 100644
--- a/drivers/media/video/uvc/uvcvideo.h
+++ b/drivers/media/video/uvc/uvcvideo.h
@@ -436,7 +436,9 @@ struct uvc_streaming {
struct uvc_streaming_control ctrl;
struct uvc_format *cur_format;
struct uvc_frame *cur_frame;
-
+ /* Protect access to ctrl, cur_format, cur_frame and hardware video
+ * probe control.
+ */
struct mutex mutex;
unsigned int frozen : 1;
--
1.7.2.2
--
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