[PATCH v5 67/80] drm/vc4: hdmi: Set the b-frame marker to the match ALSA's default.

Maxime Ripard maxime at cerno.tech
Thu Sep 3 04:01:39 EDT 2020


From: Dave Stevenson <dave.stevenson at raspberrypi.com>

ALSA's iec958 plugin by default sets the block start preamble
to 8, whilst this driver was programming the hardware to expect
0xF.
Amend the hardware config to match ALSA.

Tested-by: Chanwoo Choi <cw00.choi at samsung.com>
Tested-by: Hoegeun Kwon <hoegeun.kwon at samsung.com>
Tested-by: Stefan Wahren <stefan.wahren at i2se.com>
Signed-off-by: Dave Stevenson <dave.stevenson at raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime at cerno.tech>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 43e59466b1d8..d8137b838326 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -754,10 +754,11 @@ static int vc4_hdmi_audio_hw_params(struct snd_pcm_substream *substream,
 
 	vc4_hdmi_audio_set_mai_clock(vc4_hdmi);
 
+	/* The B frame identifier should match the value used by alsa-lib (8) */
 	audio_packet_config =
 		VC4_HDMI_AUDIO_PACKET_ZERO_DATA_ON_SAMPLE_FLAT |
 		VC4_HDMI_AUDIO_PACKET_ZERO_DATA_ON_INACTIVE_CHANNELS |
-		VC4_SET_FIELD(0xf, VC4_HDMI_AUDIO_PACKET_B_FRAME_IDENTIFIER);
+		VC4_SET_FIELD(0x8, VC4_HDMI_AUDIO_PACKET_B_FRAME_IDENTIFIER);
 
 	channel_mask = GENMASK(vc4_hdmi->audio.channels - 1, 0);
 	audio_packet_config |= VC4_SET_FIELD(channel_mask,
-- 
git-series 0.9.1



More information about the linux-arm-kernel mailing list