[media] uvcvideo: Disable hardware timestamps by default

The hardware timestamping implementation has been reported as not
working correctly on at least the Logitech C920. Until this can be
fixed, disable it by default.

Reported-by: Peter Rabbitson <rabbit@rabbit.us>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c
index 4b5b3e8fb7d38358c53a3eb806f56639e18eaebb..d11fd6ac2df050369a06641ade6e91fd2fddc649 100644 (file)
--- a/drivers/media/usb/uvc/uvc_driver.c
+++ b/drivers/media/usb/uvc/uvc_driver.c
@@ -32,6 +32,7 @@
 #define DRIVER_DESC            "USB Video Class driver"
 
 unsigned int uvc_clock_param = CLOCK_MONOTONIC;
+unsigned int uvc_hw_timestamps_param;
 unsigned int uvc_no_drop_param;
 static unsigned int uvc_quirks_param = -1;
 unsigned int uvc_trace_param;
@@ -2078,6 +2079,8 @@ static int uvc_clock_param_set(const char *val, struct kernel_param *kp)
 module_param_call(clock, uvc_clock_param_set, uvc_clock_param_get,
                  &uvc_clock_param, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(clock, "Video buffers timestamp clock");
+module_param_named(hwtimestamps, uvc_hw_timestamps_param, uint, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(hwtimestamps, "Use hardware timestamps");
 module_param_named(nodrop, uvc_no_drop_param, uint, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(nodrop, "Don't drop incomplete frames");
 module_param_named(quirks, uvc_quirks_param, uint, S_IRUGO|S_IWUSR);

diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c
index f839654ea4369fa7645f579f7ab5b94189055611..1c4a11766fd1025700a0f7a45f4a53869a6b6641 100644 (file)
--- a/drivers/media/usb/uvc/uvc_video.c
+++ b/drivers/media/usb/uvc/uvc_video.c
@@ -623,6 +623,9 @@ void uvc_video_clock_update(struct uvc_streaming *stream,
        u32 rem;
        u64 y;
 
+       if (!uvc_hw_timestamps_param)
+               return;
+
        spin_lock_irqsave(&clock->lock, flags);
 
        if (clock->count < clock->size)

diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index 816dd1a0fd81de34329aef1f72a62bf9f9980deb..1374bd9575760843d142d47972c32a60ce199e65 100644 (file)
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -593,6 +593,7 @@ extern unsigned int uvc_clock_param;
 extern unsigned int uvc_no_drop_param;
 extern unsigned int uvc_trace_param;
 extern unsigned int uvc_timeout_param;
+extern unsigned int uvc_hw_timestamps_param;
 
 #define uvc_trace(flag, msg...) \
        do { \