On Thu Mar 27 21:05:27 2025 +0000, Ricardo Ribalda wrote:
> Add a variable in the file handle state to figure out if a camera is in
> the streaming state or not. This variable will be used in the future for
> power management policies.
>
> Now that we are at it, make use of guards to simplify the code.
>
> Reviewed-by: Laurent Pinchart <[email protected]>
> Reviewed-by: Hans de Goede <[email protected]>
> Signed-off-by: Ricardo Ribalda <[email protected]>
> Message-ID: <[email protected]>
> Signed-off-by: Hans de Goede <[email protected]>
> Signed-off-by: Hans Verkuil <[email protected]>
Patch committed.
Thanks,
Hans Verkuil
drivers/media/usb/uvc/uvc_v4l2.c | 18 +++++++++++++-----
drivers/media/usb/uvc/uvcvideo.h | 1 +
2 files changed, 14 insertions(+), 5 deletions(-)
---
diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
index 39065db44e86..22886b47d81c 100644
--- a/drivers/media/usb/uvc/uvc_v4l2.c
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -841,11 +841,18 @@ static int uvc_ioctl_streamon(struct file *file, void *fh,
if (!uvc_has_privileges(handle))
return -EBUSY;
- mutex_lock(&stream->mutex);
+ guard(mutex)(&stream->mutex);
+
+ if (handle->is_streaming)
+ return 0;
+
ret = uvc_queue_streamon(&stream->queue, type);
- mutex_unlock(&stream->mutex);
+ if (ret)
+ return ret;
- return ret;
+ handle->is_streaming = true;
+
+ return 0;
}
static int uvc_ioctl_streamoff(struct file *file, void *fh,
@@ -857,9 +864,10 @@ static int uvc_ioctl_streamoff(struct file *file, void *fh,
if (!uvc_has_privileges(handle))
return -EBUSY;
- mutex_lock(&stream->mutex);
+ guard(mutex)(&stream->mutex);
+
uvc_queue_streamoff(&stream->queue, type);
- mutex_unlock(&stream->mutex);
+ handle->is_streaming = false;
return 0;
}
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index b4ee701835fc..5ceb01e7831a 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -630,6 +630,7 @@ struct uvc_fh {
struct uvc_streaming *stream;
enum uvc_handle_state state;
unsigned int pending_async_ctrls;
+ bool is_streaming;
};
/* ------------------------------------------------------------------------
