On Mon Feb 24 10:34:53 2025 +0000, Ricardo Ribalda wrote:
> If we let know our callers that we have not done anything, they will be
> able to optimize their decisions.
>
> Cc: [email protected]
> Fixes: b4012002f3a3 ("[media] uvcvideo: Add support for control events")
> Reviewed-by: Laurent Pinchart <[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_ctrl.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
---
diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index e2052130f4c9..0c4d84eab42a 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -2101,12 +2101,17 @@ int uvc_ctrl_begin(struct uvc_video_chain *chain)
return mutex_lock_interruptible(&chain->ctrl_mutex) ? -ERESTARTSYS : 0;
}
+/*
+ * Returns the number of uvc controls that have been correctly set, or a
+ * negative number if there has been an error.
+ */
static int uvc_ctrl_commit_entity(struct uvc_device *dev,
struct uvc_fh *handle,
struct uvc_entity *entity,
int rollback,
struct uvc_control **err_ctrl)
{
+ unsigned int processed_ctrls = 0;
struct uvc_control *ctrl;
unsigned int i;
int ret;
@@ -2141,6 +2146,9 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev,
else
ret = 0;
+ if (!ret)
+ processed_ctrls++;
+
if (rollback || ret < 0)
memcpy(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP),
@@ -2159,7 +2167,7 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev,
}
}
- return 0;
+ return processed_ctrls;
}
static int uvc_ctrl_find_ctrl_idx(struct uvc_entity *entity,
@@ -2206,6 +2214,7 @@ int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
if (!rollback)
uvc_ctrl_send_events(handle, ctrls->controls, ctrls->count);
+ ret = 0;
done:
mutex_unlock(&chain->ctrl_mutex);
return ret;
