> On 20 Jan 2026, at 4:52 pm, Cristian Ciocaltea > <[email protected]> wrote: > > Hi Christian, > > On 12/6/25 9:27 AM, Christian Hewitt wrote: >> From: Jonas Karlman <[email protected]> >> >> Channel Allocation (PB4) and Level Shift Information (PB5) are >> configured with values from PB1 and PB2 due to the wrong offset >> being used. This results in missing audio channels or incorrect >> speaker placement when playing multi-channel audio. >> >> Use the correct offset to fix multi-channel audio output. >> >> Fixes: fd0141d1a8a2 ("drm/bridge: synopsys: Add audio support for >> dw-hdmi-qp") >> Reported-by: Christian Hewitt <[email protected]> >> Signed-off-by: Jonas Karlman <[email protected]> Signed-off-by: Christian Hewitt <[email protected]>
>> --- >> buffer is a pointer to u8 while data written to PKT_AUDI_CONTENTS >> is u32, so buffer contains audio infoframe header (buffer[0:2]) + >> checksum (buffer[3]) + payload byte 1-10 (buffer[4:13]), e.g. >> >> regmap_bulk_write(hdmi->regm, PKT_AUDI_CONTENTS1, &buffer[3], 1) >> .. will write PB0-PB3 to AUDI_CONTENTS1 >> >> regmap_bulk_write(hdmi->regm, PKT_AUDI_CONTENTS2, &buffer[4], 1) >> .. will write PB1-PB4 to AUDI_CONTENTS2, but should be PB4-PB7 >> >> &buffer[4] will point to payload byte 4 not payload byte 1, due >> to u8/u32 and not considering the size of header+checksum (3+1). >> --- >> drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c >> b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c >> index f3a13da488e6..7b8a69383dc4 100644 >> --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c >> +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c >> @@ -845,7 +845,7 @@ static int dw_hdmi_qp_config_audio_infoframe(struct >> dw_hdmi_qp *hdmi, >> >> regmap_bulk_write(hdmi->regm, PKT_AUDI_CONTENTS0, &header_bytes, 1); >> regmap_bulk_write(hdmi->regm, PKT_AUDI_CONTENTS1, &buffer[3], 1); >> - regmap_bulk_write(hdmi->regm, PKT_AUDI_CONTENTS2, &buffer[4], 1); >> + regmap_bulk_write(hdmi->regm, PKT_AUDI_CONTENTS2, &buffer[7], 1); > > Since making use of regmap_bulk_write(), this could be further optimized as: > > - regmap_bulk_write(hdmi->regm, PKT_AUDI_CONTENTS1, &buffer[3], 1); > - regmap_bulk_write(hdmi->regm, PKT_AUDI_CONTENTS2, &buffer[4], 1); > + regmap_bulk_write(hdmi->regm, PKT_AUDI_CONTENTS1, &buffer[3], 2); > > Regardless, > > Reviewed-by: Cristian Ciocaltea <[email protected]> > > Please note you also need to provide your SoB, check "Sign your work ..." > section in [1]. Ahh, I was hoping to just forward Jonas’ patch. If it’s possible to apply the SoB above when merging, please do. If not I can send a v2 series (someone let me know). Christian > Regards, > Cristian > > [1] https://www.kernel.org/doc/Documentation/process/submitting-patches.rst
