[PATCH] ASoC: SOF: ipc4-topology: set playback channel mask

[PATCH] ASoC: SOF: ipc4-topology: set playback channel mask

[Peter Ujfalusi]

From: Bard Liao <yung-chuan.liao@linux.intel.com>

Currently, we send all channels to all amps and copy the channel_mask
to all ALH DMAs in playback. However, the amp may not have the
capability to run any process and SOF may need to split the channels
and send specific data channel to each amp. In that case, we need
to split the channel_mask in ALH DMA.
Copy the channel mask only if the widget channel count is the same
the FE channels for playback, otherwise, split the channels among the
aggregated DAIs. Like what we did in capture.

Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Liam Girdwood <liam.r.girdwood@intel.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
---
 sound/soc/sof/ipc4-topology.c | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/sound/soc/sof/ipc4-topology.c b/sound/soc/sof/ipc4-topology.c
index 221e9d4052b8..588defd3eec9 100644
--- a/sound/soc/sof/ipc4-topology.c
+++ b/sound/soc/sof/ipc4-topology.c
@@ -2280,8 +2280,19 @@ sof_ipc4_prepare_copier_module(struct snd_sof_widget *swidget,
 				ch_map >>= 4;
 			}
 
-			step = ch_count / blob->alh_cfg.device_count;
-			mask =  GENMASK(step - 1, 0);
+			if (swidget->id == snd_soc_dapm_dai_in && ch_count == out_ref_channels) {
+				/*
+				 * For playback DAI widgets where the channel number is equal to
+				 * the output reference channels, set the step = 0 to ensure all
+				 * the ch_mask is applied to all alh mappings.
+				 */
+				mask = ch_mask;
+				step = 0;
+			} else {
+				step = ch_count / blob->alh_cfg.device_count;
+				mask =  GENMASK(step - 1, 0);
+			}
+
 			/*
 			 * Set each gtw_cfg.node_id to blob->alh_cfg.mapping[]
 			 * for all widgets with the same stream name
@@ -2316,8 +2327,9 @@ sof_ipc4_prepare_copier_module(struct snd_sof_widget *swidget,
 				}
 
 				/*
-				 * Set the same channel mask for playback as the audio data is
-				 * duplicated for all speakers. For capture, split the channels
+				 * Set the same channel mask if the widget channel count is the same
+				 * as the FE channels for playback as the audio data is duplicated
+				 * for all speakers in this case. Otherwise, split the channels
 				 * among the aggregated DAIs. For example, with 4 channels on 2
 				 * aggregated DAIs, the channel_mask should be 0x3 and 0xc for the
 				 * two DAI's.
@@ -2326,10 +2338,7 @@ sof_ipc4_prepare_copier_module(struct snd_sof_widget *swidget,
 				 * the tables in soc_acpi files depending on the _ADR and devID
 				 * registers for each codec.
 				 */
-				if (w->id == snd_soc_dapm_dai_in)
-					blob->alh_cfg.mapping[i].channel_mask = ch_mask;
-				else
-					blob->alh_cfg.mapping[i].channel_mask = mask << (step * i);
+				blob->alh_cfg.mapping[i].channel_mask = mask << (step * i);
 
 				i++;
 			}
-- 
2.52.0

Re: [PATCH] ASoC: SOF: ipc4-topology: set playback channel mask

[Mark Brown]

On Mon, 15 Dec 2025 15:07:23 +0200, Peter Ujfalusi wrote:
> Currently, we send all channels to all amps and copy the channel_mask
> to all ALH DMAs in playback. However, the amp may not have the
> capability to run any process and SOF may need to split the channels
> and send specific data channel to each amp. In that case, we need
> to split the channel_mask in ALH DMA.
> Copy the channel mask only if the widget channel count is the same
> the FE channels for playback, otherwise, split the channels among the
> aggregated DAIs. Like what we did in capture.
> 
> [...]

Applied to

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

Thanks!

[1/1] ASoC: SOF: ipc4-topology: set playback channel mask
      commit: da230e232352750a80c8fc883eac1c87c8849027

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