media: uvcvideo: Provide sync and async uvc_ctrl_status_event

Split the functionality of void uvc_ctrl_status_event_work in two, so it
can be called by functions outside interrupt context and not part of an
URB.
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/usb/uvc/uvc_ctrl.c

@@ -1254,17 +1254,12 @@ static void uvc_ctrl_send_slave_event(struct uvc_video_chain *chain,
 	uvc_ctrl_send_event(chain, handle, ctrl, mapping, val, changes);
 }
 
-static void uvc_ctrl_status_event_work(struct work_struct *work)
+void uvc_ctrl_status_event(struct uvc_video_chain *chain,
+			   struct uvc_control *ctrl, const u8 *data)
 {
-	struct uvc_device *dev = container_of(work, struct uvc_device,
-					      async_ctrl.work);
-	struct uvc_ctrl_work *w = &dev->async_ctrl;
-	struct uvc_video_chain *chain = w->chain;
 	struct uvc_control_mapping *mapping;
-	struct uvc_control *ctrl = w->ctrl;
 	struct uvc_fh *handle;
 	unsigned int i;
-	int ret;
 
 	mutex_lock(&chain->ctrl_mutex);
 
@@ -1272,7 +1267,7 @@ static void uvc_ctrl_status_event_work(struct work_struct *work)
 	ctrl->handle = NULL;
 
 	list_for_each_entry(mapping, &ctrl->info.mappings, list) {
-		s32 value = __uvc_ctrl_get_value(mapping, w->data);
+		s32 value = __uvc_ctrl_get_value(mapping, data);
 
 		/*
 		 * handle may be NULL here if the device sends auto-update
@@ -1291,6 +1286,16 @@ static void uvc_ctrl_status_event_work(struct work_struct *work)
 	}
 
 	mutex_unlock(&chain->ctrl_mutex);
+}
+
+static void uvc_ctrl_status_event_work(struct work_struct *work)
+{
+	struct uvc_device *dev = container_of(work, struct uvc_device,
+					      async_ctrl.work);
+	struct uvc_ctrl_work *w = &dev->async_ctrl;
+	int ret;
+
+	uvc_ctrl_status_event(w->chain, w->ctrl, w->data);
 
 	/* Resubmit the URB. */
 	w->urb->interval = dev->int_ep->desc.bInterval;
@@ -1300,8 +1305,8 @@ static void uvc_ctrl_status_event_work(struct work_struct *work)
 			   ret);
 }
 
-bool uvc_ctrl_status_event(struct urb *urb, struct uvc_video_chain *chain,
-			   struct uvc_control *ctrl, const u8 *data)
+bool uvc_ctrl_status_event_async(struct urb *urb, struct uvc_video_chain *chain,
+				 struct uvc_control *ctrl, const u8 *data)
 {
 	struct uvc_device *dev = chain->dev;
 	struct uvc_ctrl_work *w = &dev->async_ctrl;

drivers/media/usb/uvc/uvc_status.c

@@ -179,7 +179,8 @@ static bool uvc_event_control(struct urb *urb,
 
 	switch (status->bAttribute) {
 	case UVC_CTRL_VALUE_CHANGE:
-		return uvc_ctrl_status_event(urb, chain, ctrl, status->bValue);
+		return uvc_ctrl_status_event_async(urb, chain, ctrl,
+						   status->bValue);
 
 	case UVC_CTRL_INFO_CHANGE:
 	case UVC_CTRL_FAILURE_CHANGE:

drivers/media/usb/uvc/uvcvideo.h

@@ -844,7 +844,9 @@ int uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
 int uvc_ctrl_init_device(struct uvc_device *dev);
 void uvc_ctrl_cleanup_device(struct uvc_device *dev);
 int uvc_ctrl_restore_values(struct uvc_device *dev);
-bool uvc_ctrl_status_event(struct urb *urb, struct uvc_video_chain *chain,
+bool uvc_ctrl_status_event_async(struct urb *urb, struct uvc_video_chain *chain,
+				 struct uvc_control *ctrl, const u8 *data);
+void uvc_ctrl_status_event(struct uvc_video_chain *chain,
 			   struct uvc_control *ctrl, const u8 *data);
 
 int uvc_ctrl_begin(struct uvc_video_chain *chain);