Unverified Commit 62a7b3bb authored Aug 19, 2025 by Richard Fitzgerald Committed by Mark Brown Sep 18, 2025

ASoC: SOF: ipc4-pcm: Fix incorrect comparison with number of tdm_slots

In ipc4_ssp_dai_config_pcm_params_match() when comparing params_channels()
against hw_config->tdm_slots the comparison should be a <= not a ==.

The number of TDM slots must be enough for the number of required channels.
But it can be greater. There are various reason why a I2S/TDM link has more
TDM slots than a particular audio stream needs.

The original comparison would fail on systems that had more TDM slots.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 8a07944a ("ASoC: SOF: ipc4-pcm: Look for best matching hw_config for SSP")
Link: https://patch.msgid.link/20250819160525.423416-1-rf@opensource.cirrus.com

Signed-off-by: Mark Brown <broonie@kernel.org>

parent 1dd28fd8

sound/soc/sof/ipc4-pcm.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -639,14 +639,14 @@ static int ipc4_ssp_dai_config_pcm_params_match(struct snd_sof_dev *sdev,

		if (params_rate(params) == le32_to_cpu(hw_config->fsync_rate) &&
		params_width(params) == le32_to_cpu(hw_config->tdm_slot_width) &&
		params_channels(params) == le32_to_cpu(hw_config->tdm_slots)) {
		params_channels(params) <= le32_to_cpu(hw_config->tdm_slots)) {
		current_config = le32_to_cpu(hw_config->id);
		partial_match = false;
		/* best match found */
		break;
		} else if (current_config < 0 &&
		params_rate(params) == le32_to_cpu(hw_config->fsync_rate) &&
		params_channels(params) == le32_to_cpu(hw_config->tdm_slots)) {
		params_channels(params) <= le32_to_cpu(hw_config->tdm_slots)) {
		current_config = le32_to_cpu(hw_config->id);
		partial_match = true;
		/* keep looking for better match */