From: Dom Cobley popcornmix@gmail.com
stable inclusion from stable-v5.10.137 commit b161b270677625eff5fa89ba6d94e28a6ad7a0f5 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
--------------------------------
[ Upstream commit 8434111ccfec8fc0549ec325a632067232d38e14 ]
This was a workaround for bugs in hardware on earlier Pi models and wasn't totally successful.
It makes audio quality worse on a Pi4 at the higher sample rates
Signed-off-by: Dom Cobley popcornmix@gmail.com Signed-off-by: Maxime Ripard maxime@cerno.tech Link: https://patchwork.freedesktop.org/patch/msgid/20210525132354.297468-10-maxim... Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Reviewed-by: Wei Li liwei391@huawei.com --- drivers/gpu/drm/vc4/vc4_hdmi.c | 22 ++++++---------------- 1 file changed, 6 insertions(+), 16 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index d5822878b5a7..6acc34f1e095 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -1031,22 +1031,12 @@ static int vc4_hdmi_audio_hw_params(struct snd_pcm_substream *substream, audio_packet_config |= VC4_SET_FIELD(channel_mask, VC4_HDMI_AUDIO_PACKET_CEA_MASK);
- /* Set the MAI threshold. This logic mimics the firmware's. */ - if (vc4_hdmi->audio.samplerate > 96000) { - HDMI_WRITE(HDMI_MAI_THR, - VC4_SET_FIELD(0x12, VC4_HD_MAI_THR_DREQHIGH) | - VC4_SET_FIELD(0x12, VC4_HD_MAI_THR_DREQLOW)); - } else if (vc4_hdmi->audio.samplerate > 48000) { - HDMI_WRITE(HDMI_MAI_THR, - VC4_SET_FIELD(0x14, VC4_HD_MAI_THR_DREQHIGH) | - VC4_SET_FIELD(0x12, VC4_HD_MAI_THR_DREQLOW)); - } else { - HDMI_WRITE(HDMI_MAI_THR, - VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_PANICHIGH) | - VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_PANICLOW) | - VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_DREQHIGH) | - VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_DREQLOW)); - } + /* Set the MAI threshold */ + HDMI_WRITE(HDMI_MAI_THR, + VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_PANICHIGH) | + VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_PANICLOW) | + VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_DREQHIGH) | + VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_DREQLOW));
HDMI_WRITE(HDMI_MAI_CONFIG, VC4_HDMI_MAI_CONFIG_BIT_REVERSE |