From b1accfa15533fdd40280aae3102e9599e63a7c10 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Sat, 27 Sep 2008 20:54:02 -0300 Subject: [PATCH] V4L/DVB (9036): uvcvideo: Fix control cache access when setting composite auto-update controls Auto-update controls are never marked is loaded to prevent uvc_get_ctrl from loading the control value from the cache. When setting a composite (mapped to several V4L2 controls) auto-update UVC control, the driver updates the control cache value before processing each V4L2 control, overwriting the previously set V4L2 control. This fixes the problem by marking all controls as loaded in uvc_set_ctrl regardless of their type and resetting the loaded flag in uvc_commit_ctrl for auto-update controls. Signed-off-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/uvc/uvc_ctrl.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) diff --git a/drivers/media/video/uvc/uvc_ctrl.c b/drivers/media/video/uvc/uvc_ctrl.c index 088437a5f60c..f16aafe9cf14 100644 --- a/drivers/media/video/uvc/uvc_ctrl.c +++ b/drivers/media/video/uvc/uvc_ctrl.c @@ -837,7 +837,17 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev, for (i = 0; i < entity->ncontrols; ++i) { ctrl = &entity->controls[i]; - if (ctrl->info == NULL || !ctrl->dirty) + if (ctrl->info == NULL) + continue; + + /* Reset the loaded flag for auto-update controls that were + * marked as loaded in uvc_ctrl_get/uvc_ctrl_set to prevent + * uvc_ctrl_get from using the cached value. + */ + if (ctrl->info->flags & UVC_CONTROL_AUTO_UPDATE) + ctrl->loaded = 0; + + if (!ctrl->dirty) continue; if (!rollback) @@ -853,9 +863,6 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev, uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP), ctrl->info->size); - if ((ctrl->info->flags & UVC_CONTROL_GET_CUR) == 0) - ctrl->loaded = 0; - ctrl->dirty = 0; if (ret < 0) @@ -913,8 +920,7 @@ int uvc_ctrl_get(struct uvc_video_device *video, if (ret < 0) return ret; - if ((ctrl->info->flags & UVC_CONTROL_AUTO_UPDATE) == 0) - ctrl->loaded = 1; + ctrl->loaded = 1; } xctrl->value = uvc_get_le_value( @@ -965,8 +971,7 @@ int uvc_ctrl_set(struct uvc_video_device *video, return ret; } - if ((ctrl->info->flags & UVC_CONTROL_AUTO_UPDATE) == 0) - ctrl->loaded = 1; + ctrl->loaded = 1; } if (!ctrl->dirty) {