[PATCH AUTOSEL 6.9 06/11] ASoC: SOF: Intel: hda-pcm: Limit the maximum number of periods by MAX_BDL_ENTRIES

From: Sasha Levin
Date: Tue Jul 16 2024 - 14:33:37 EST


From: Peter Ujfalusi <peter.ujfalusi@xxxxxxxxxxxxxxx>

[ Upstream commit 82bb8db96610b558920b8c57cd250ec90567d79b ]

The HDaudio specification Section 3.6.2 limits the number of BDL entries to 256.

Make sure we don't allow more periods than this normative value.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxxxxxxxxxxx>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Link: https://patch.msgid.link/20240704090106.371497-1-pierre-louis.bossart@xxxxxxxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
sound/soc/sof/intel/hda-pcm.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/sound/soc/sof/intel/hda-pcm.c b/sound/soc/sof/intel/hda-pcm.c
index d7b446f3f973e..8b5fbbc777bd4 100644
--- a/sound/soc/sof/intel/hda-pcm.c
+++ b/sound/soc/sof/intel/hda-pcm.c
@@ -254,6 +254,12 @@ int hda_dsp_pcm_open(struct snd_sof_dev *sdev,
snd_pcm_hw_constraint_integer(substream->runtime,
SNDRV_PCM_HW_PARAM_PERIODS);

+ /* Limit the maximum number of periods to not exceed the BDL entries count */
+ if (runtime->hw.periods_max > HDA_DSP_MAX_BDL_ENTRIES)
+ snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIODS,
+ runtime->hw.periods_min,
+ HDA_DSP_MAX_BDL_ENTRIES);
+
/* Only S16 and S32 supported by HDA hardware when used without DSP */
if (sdev->dspless_mode_selected)
snd_pcm_hw_constraint_mask64(substream->runtime, SNDRV_PCM_HW_PARAM_FORMAT,
--
2.43.0