This is a partial revert (in a cleaner way) of commit ebf08ae3bc90 ("ASoC: fsl_ssi: Keep ssi->i2s_net updated") to fix a regression at test cases when switching between mono and stereo audio.
The problem is that ssi->i2s_net is initialized in set_dai_fmt() only, while this set_dai_fmt() is only called during the dai-link probe(). The original patch assumed set_dai_fmt() would be called during every playback instance, so it failed at the overriding use cases.
This patch adds the local variable i2s_net back to let regular use cases still follow the mode settings from the set_dai_fmt().
Meanwhile, the original commit of keeping ssi->i2s_net updated was to make set_tdm_slot() clean by checking the ssi->i2s_net directly instead of reading SCR register. However, the change itself is not necessary (or even harmful) because the set_tdm_slot() might fail to check the slot number for Normal-Mode-None-Net settings while mono audio cases still need 2 slots. So this patch can also fix it. And it adds an extra line of comments to declare ssi->i2s_net does not reflect the register value but merely the initial setting from the set_dai_fmt().
Reported-by: Mika Penttilä mika.penttila@nextfour.com Signed-off-by: Nicolin Chen nicoleotsuka@gmail.com Cc: Mika Penttilä mika.penttila@nextfour.com --- sound/soc/fsl/fsl_ssi.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/sound/soc/fsl/fsl_ssi.c b/sound/soc/fsl/fsl_ssi.c index 0823b08..89df2d9 100644 --- a/sound/soc/fsl/fsl_ssi.c +++ b/sound/soc/fsl/fsl_ssi.c @@ -217,6 +217,7 @@ struct fsl_ssi_soc_data { * @dai_fmt: DAI configuration this device is currently used with * @streams: Mask of current active streams: BIT(TX) and BIT(RX) * @i2s_net: I2S and Network mode configurations of SCR register + * (this is the initial settings based on the DAI format) * @synchronous: Use synchronous mode - both of TX and RX use STCK and SFCK * @use_dma: DMA is used or FIQ with stream filter * @use_dual_fifo: DMA with support for dual FIFO mode @@ -829,16 +830,23 @@ static int fsl_ssi_hw_params(struct snd_pcm_substream *substream, }
if (!fsl_ssi_is_ac97(ssi)) { + /* + * Keep the ssi->i2s_net intact while having a local variable + * to override settings for special use cases. Otherwise, the + * ssi->i2s_net will lose the settings for regular use cases. + */ + u8 i2s_net = ssi->i2s_net; + /* Normal + Network mode to send 16-bit data in 32-bit frames */ if (fsl_ssi_is_i2s_cbm_cfs(ssi) && sample_size == 16) - ssi->i2s_net = SSI_SCR_I2S_MODE_NORMAL | SSI_SCR_NET; + i2s_net = SSI_SCR_I2S_MODE_NORMAL | SSI_SCR_NET;
/* Use Normal mode to send mono data at 1st slot of 2 slots */ if (channels == 1) - ssi->i2s_net = SSI_SCR_I2S_MODE_NORMAL; + i2s_net = SSI_SCR_I2S_MODE_NORMAL;
regmap_update_bits(regs, REG_SSI_SCR, - SSI_SCR_I2S_NET_MASK, ssi->i2s_net); + SSI_SCR_I2S_NET_MASK, i2s_net); }
/* In synchronous mode, the SSI uses STCCR for capture */