11.11.2013 17:55, Alex Deucher kirjoitti:
On Fri, Nov 8, 2013 at 6:24 AM, Anssi Hannula anssi.hannula@iki.fi wrote:
18.10.2013 23:41, Alex Deucher kirjoitti:
Needed by the hda driver to properly set up synchronization on the audio side.
Signed-off-by: Alex Deucher alexander.deucher@amd.com
drivers/gpu/drm/radeon/evergreen_hdmi.c | 37 ++++++++++++++++++++++++++++++++ drivers/gpu/drm/radeon/evergreend.h | 38 +++++++++++++++++++++++++++++++++ 2 files changed, 75 insertions(+)
diff --git a/drivers/gpu/drm/radeon/evergreen_hdmi.c b/drivers/gpu/drm/radeon/evergreen_hdmi.c index 5fbe486..abdc893 100644 --- a/drivers/gpu/drm/radeon/evergreen_hdmi.c +++ b/drivers/gpu/drm/radeon/evergreen_hdmi.c
[...]
if (connector->latency_present[0])tmp = VIDEO_LIPSYNC(connector->video_latency[0]) |AUDIO_LIPSYNC(connector->audio_latency[0]);elsetmp = VIDEO_LIPSYNC(255) | AUDIO_LIPSYNC(255);}WREG32(AZ_F0_CODEC_PIN0_CONTROL_RESPONSE_LIPSYNC, tmp);[...]
+#define AZ_F0_CODEC_PIN0_CONTROL_RESPONSE_LIPSYNC 0x5fe8 +# define VIDEO_LIPSYNC(x) (((x) & 0xff) << 0) +# define AUDIO_LIPSYNC(x) (((x) & 0xff) << 8) +/* VIDEO_LIPSYNC, AUDIO_LIPSYNC
- 0 = invalid
- x = legal delay value
- 255 = sync not supported
- */
Hmm, AMD_HDA_verbs_v2.pdf says that: 0 = unknown latency
HDMI spec 1.4 says that: 0 = not valid or unknown latency 1..251 = valid delay value 255 = video not supported / audio not supported
Are you sure you shouldn't use 0 instead for unknown (no latency_present)?
I'm not sure. The comment in the code above is what the register spec says which seems to match the HDMI spec. I can dig around a bit more internally.
OK, though don't waste too much time on that, ALSA has to handle 0 and 255 the same in any case (a patch has just been pushed to sound git to handle 255). :)