[PATCH v3] ASoC: qcom: sc8280xp: Derive TDM channels from DT mask

[PATCH v3] ASoC: qcom: sc8280xp: Derive TDM channels from DT mask

[Shawn Guo]

Derive the backend channel count of TDM DAIs from the cpu DAI TDM
slot mask in the DT, using the same DAI ID ranges and tx/rx mask
selection as q6tdm_set_tdm_slot(), so the channel count always matches
the number of slots programmed into the DSP. Each board then gets the
channel count its dai-link describes, e.g. 4/4 on Nord RRD, 6/4 on
RIDE. Keep the default of two when the link has no TDM slot
description, and fail the fixup on an invalid one.

Signed-off-by: Shawn Guo <shengchao.guo@oss.qualcomm.com>
---
Changes for v3:
- Propagate qcom_snd_get_dai_tdm_slots() errors other than -ENOENT
  instead of silently falling back to two channels (Prasad)
- Link to v2: https://lore.kernel.org/all/20261029022340.591372-1-shengchao.guo@oss.qualcomm.com/

Changes for v2:
- Cover all TDM DAIs (PRIMARY..QUINARY and AIF_TDM ranges), matching
  q6tdm_set_tdm_slot(), instead of only AIF_TDM_RX_8/TX_8 (Rafi)
- Link to v1: https://lore.kernel.org/all/20261021025310.2072026-1-shengchao.guo@oss.qualcomm.com/

 sound/soc/qcom/sc8280xp.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/sound/soc/qcom/sc8280xp.c b/sound/soc/qcom/sc8280xp.c
index 9aae6aadd43d..8cc75a7ad866 100644
--- a/sound/soc/qcom/sc8280xp.c
+++ b/sound/soc/qcom/sc8280xp.c
@@ -303,6 +303,26 @@ static int sc8280xp_be_hw_params_fixup(struct snd_soc_pcm_runtime *rtd,
 	channels->min = 2;
 	channels->max = 2;
 	switch (cpu_dai->id) {
+	case PRIMARY_TDM_RX_0 ... QUINARY_TDM_TX_7:
+	case AIF_TDM_RX_0 ... AIF_TDM_TX_12: {
+		struct qcom_snd_tdm_slot_cfg cpu_cfg, codec_cfg;
+		unsigned int mask;
+		int ret;
+
+		ret = qcom_snd_get_dai_tdm_slots(rtd, &cpu_cfg, &codec_cfg);
+		if (ret == -ENOENT)
+			break;
+		if (ret)
+			return ret;
+
+		/* Same slot mask selection as q6tdm_set_tdm_slot() */
+		mask = (cpu_dai->id & 0x1) ? cpu_cfg.tx_mask : cpu_cfg.rx_mask;
+		if (mask) {
+			channels->min = hweight32(mask);
+			channels->max = channels->min;
+		}
+		break;
+	}
 	case TX_CODEC_DMA_TX_0:
 	case TX_CODEC_DMA_TX_1:
 	case TX_CODEC_DMA_TX_2:
-- 
2.43.0

Re: [PATCH v3] ASoC: qcom: sc8280xp: Derive TDM channels from DT mask

[Prasad Kumpatla]

On 10/31/2026 1:53 PM, Shawn Guo wrote:
> Derive the backend channel count of TDM DAIs from the cpu DAI TDM
> slot mask in the DT, using the same DAI ID ranges and tx/rx mask
> selection as q6tdm_set_tdm_slot(), so the channel count always matches
> the number of slots programmed into the DSP. Each board then gets the
> channel count its dai-link describes, e.g. 4/4 on Nord RRD, 6/4 on
> RIDE. Keep the default of two when the link has no TDM slot
> description, and fail the fixup on an invalid one.
>
> Signed-off-by: Shawn Guo <shengchao.guo@oss.qualcomm.com>
> ---
> Changes for v3:
> - Propagate qcom_snd_get_dai_tdm_slots() errors other than -ENOENT
>    instead of silently falling back to two channels (Prasad)
> - Link to v2: https://lore.kernel.org/all/20261029022340.591372-1-shengchao.guo@oss.qualcomm.com/
>
LGTM,

Reviewed-by: Prasad Kumpatla<prasad.kumpatla@oss.qualcomm.com>

Thanks,
Prasad

Re: [PATCH v3] ASoC: qcom: sc8280xp: Derive TDM channels from DT mask

[Mark Brown]

On Sat, 31 Oct 2026 16:23:18 +0800, Shawn Guo wrote:
> ASoC: qcom: sc8280xp: Derive TDM channels from DT mask

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-7.5

Thanks!

[1/1] ASoC: qcom: sc8280xp: Derive TDM channels from DT mask
      https://git.kernel.org/broonie/sound/c/45e9d148a0a7

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

Re: [PATCH v3] ASoC: qcom: sc8280xp: Derive TDM channels from DT mask

[Bartosz Golaszewski]

On Sat, Oct 31, 2026 at 04:23:18PM +0800, Shawn Guo wrote:
> Derive the backend channel count of TDM DAIs from the cpu DAI TDM
> slot mask in the DT, using the same DAI ID ranges and tx/rx mask
> selection as q6tdm_set_tdm_slot(), so the channel count always matches
> the number of slots programmed into the DSP. Each board then gets the
> channel count its dai-link describes, e.g. 4/4 on Nord RRD, 6/4 on
> RIDE. Keep the default of two when the link has no TDM slot
> description, and fail the fixup on an invalid one.
> 
> Signed-off-by: Shawn Guo <shengchao.guo@oss.qualcomm.com>
> ---
 
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>