media: uvcvideo: Only save async fh if success

Now we keep a reference to the active fh for any call to uvc_ctrl_set,
regardless if it is an actual set or if it is a just a try or if the
device refused the operation.

We should only keep the file handle if the device actually accepted
applying the operation.

Cc: stable@vger.kernel.org
Fixes: e5225c820c05 ("media: uvcvideo: Send a control event when a Control Change interrupt arrives")
Suggested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Link: https://lore.kernel.org/r/20241203-uvc-fix-async-v6-1-26c867231118@chromium.org
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index bab9fdac98e6306b2518f4e7b9b44df86a50b346..e0806641a8d00878db905c741821bb13535bf06b 100644 (file)
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -1811,7 +1811,10 @@ int uvc_ctrl_begin(struct uvc_video_chain *chain)
 }
 
 static int uvc_ctrl_commit_entity(struct uvc_device *dev,
-       struct uvc_entity *entity, int rollback, struct uvc_control **err_ctrl)
+                                 struct uvc_fh *handle,
+                                 struct uvc_entity *entity,
+                                 int rollback,
+                                 struct uvc_control **err_ctrl)
 {
        struct uvc_control *ctrl;
        unsigned int i;
@@ -1859,6 +1862,10 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev,
                                *err_ctrl = ctrl;
                        return ret;
                }
+
+               if (!rollback && handle &&
+                   ctrl->info.flags & UVC_CTRL_FLAG_ASYNCHRONOUS)
+                       ctrl->handle = handle;
        }
 
        return 0;
@@ -1895,8 +1902,8 @@ int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
 
        /* Find the control. */
        list_for_each_entry(entity, &chain->entities, chain) {
-               ret = uvc_ctrl_commit_entity(chain->dev, entity, rollback,
-                                            &err_ctrl);
+               ret = uvc_ctrl_commit_entity(chain->dev, handle, entity,
+                                            rollback, &err_ctrl);
                if (ret < 0) {
                        if (ctrls)
                                ctrls->error_idx =
@@ -2046,9 +2053,6 @@ int uvc_ctrl_set(struct uvc_fh *handle,
        mapping->set(mapping, value,
                uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
 
-       if (ctrl->info.flags & UVC_CTRL_FLAG_ASYNCHRONOUS)
-               ctrl->handle = handle;
-
        ctrl->dirty = 1;
        ctrl->modified = 1;
        return 0;
@@ -2377,7 +2381,7 @@ int uvc_ctrl_restore_values(struct uvc_device *dev)
                        ctrl->dirty = 1;
                }
 
-               ret = uvc_ctrl_commit_entity(dev, entity, 0, NULL);
+               ret = uvc_ctrl_commit_entity(dev, NULL, entity, 0, NULL);
                if (ret < 0)
                        return ret;
        }