[PATCH v6 04/11] media: uvcvideo: Add uvc_ctrl_status_event_direct

[Ricardo Ribalda]

Provide a code path for events that can be sent without a work-queue,
this is, that do not belong to an URB and are not handled in the top
half on an irq-handled.

Signed-off-by: Ricardo Ribalda <riba...@chromium.org>
---
 drivers/media/usb/uvc/uvc_ctrl.c | 35 +++++++++++++++++++++++++++-----
 drivers/media/usb/uvc/uvcvideo.h |  2 ++
 2 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index 9f6174a10e73..5fe228a3213b 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -1254,17 +1254,14 @@ 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)
+static void __uvc_ctrl_status_event(struct uvc_device *dev,
+                                   struct uvc_ctrl_work *w)
 {
-       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);
 
@@ -1291,6 +1288,16 @@ 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(dev, w);
 
        /* Resubmit the URB. */
        w->urb->interval = dev->int_ep->desc.bInterval;
@@ -1321,6 +1328,24 @@ bool uvc_ctrl_status_event(struct urb *urb, struct 
uvc_video_chain *chain,
        return true;
 }
 
+void uvc_ctrl_status_event_direct(struct uvc_video_chain *chain,
+                                 struct uvc_control *ctrl, const u8 *data)
+{
+       struct uvc_device *dev = chain->dev;
+       struct uvc_ctrl_work w;
+
+       if (list_empty(&ctrl->info.mappings)) {
+               ctrl->handle = NULL;
+               return;
+       }
+
+       w.data = data;
+       w.chain = chain;
+       w.ctrl = ctrl;
+
+       __uvc_ctrl_status_event(dev, &w);
+}
+
 static bool uvc_ctrl_xctrls_has_control(const struct v4l2_ext_control *xctrls,
                                        unsigned int xctrls_count, u32 id)
 {
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index c50b0546901f..d7954dcc2b60 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -845,6 +845,8 @@ 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,
                           struct uvc_control *ctrl, const u8 *data);
+void uvc_ctrl_status_event_direct(struct uvc_video_chain *chain,
+                                 struct uvc_control *ctrl, const u8 *data);
 
 int uvc_ctrl_begin(struct uvc_video_chain *chain);
 int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
-- 
2.29.2.729.g45daf8777d-goog