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| author | Tomasz Merta <tomasz.merta@arrow.com> | 2026-04-08 10:40:56 +0200 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2026-04-08 13:24:21 +0100 |
| commit | 0669631dbccd41cf3ca7aa70213fcd8bb41c4b38 (patch) | |
| tree | b93d9b9f30c06594c9a74fbcc1e45f08305626d5 /tools/perf/scripts/python/event_analyzing_sample.py | |
| parent | 0f71866057262d669ed6a21246eaac0ad6d04d4e (diff) | |
ASoC: stm32_sai: fix incorrect BCLK polarity for DSP_A/B, LEFT_J
The STM32 SAI driver do not set the clock strobing bit (CKSTR) for DSP_A,
DSP_B and LEFT_J formats, causing data to be sampled on the wrong BCLK
edge when SND_SOC_DAIFMT_NB_NF is used.
Per ALSA convention, NB_NF requires sampling on the rising BCLK edge.
The STM32MP25 SAI reference manual states that CKSTR=1 is required for
signals received by the SAI to be sampled on the SCK rising edge.
Without setting CKSTR=1, the SAI samples on the falling edge, violating
the NB_NF convention. For comparison, the NXP FSL SAI driver correctly
sets FSL_SAI_CR2_BCP for DSP_A, DSP_B and LEFT_J, consistent with its
I2S handling.
This patch adds SAI_XCR1_CKSTR for DSP_A, DSP_B and LEFT_J in
stm32_sai_set_dai_fmt which was verified empirically with a cs47l35 codec.
RIGHT_J (LSB) is not investigated and addressed by this patch.
Note: the STM32 I2S driver (stm32_i2s_set_dai_fmt) may have the same issue
for DSP_A mode, as I2S_CGFR_CKPOL is not set. This has not been verified
and is left for a separate investigation.
Signed-off-by: Tomasz Merta <tommerta@gmail.com>
Link: https://patch.msgid.link/20260408084056.20588-1-tommerta@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'tools/perf/scripts/python/event_analyzing_sample.py')
0 files changed, 0 insertions, 0 deletions