Sorry, please ignore v2, it can't be applied successfully.
Will send v3 shortly.

Regards, 
Chancel Liu

> When configuring 32 slots TDM (channels == slots == 32), the xMR (Mask
> Register) write used:
> ~0UL - ((1 << min(channels, slots)) - 1)
> 
> The literal "1" is a signed 32-bit int. Shifting it by 32 positions is
> undefined behaviour which may set this register to 0xFFFFFFFF, masking all
> 32 slots.
> 
> Use GENMASK_U32() macro instead. For 32 slots this produces a zero mask:
> ~GENMASK_U32(31, 0) = ~0xFFFFFFFF = 0x00000000 Behaviour for fewer than 32
> slots is unchanged.
> 
> Fixes: 770f58d7d2c5 ("ASoC: fsl_sai: Support multiple data channel enable
> bits")
> Cc: [email protected]
> Signed-off-by: Chancel Liu <[email protected]>
> ---
> Changes in v2
> - Use GENMASK_U32() macro instead to make it clearer and safer
> 
>  sound/soc/fsl/fsl_sai.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c index
> 821e3bd51b6e..9661602b53c5 100644
> --- a/sound/soc/fsl/fsl_sai.c
> +++ b/sound/soc/fsl/fsl_sai.c
> @@ -797,7 +797,7 @@ static int fsl_sai_hw_params(struct snd_pcm_substream
> *substream,
>                                  FSL_SAI_CR4_FSD_MSTR, FSL_SAI_CR4_FSD_MSTR);
> 
>       regmap_write(sai->regmap, FSL_SAI_xMR(tx),
> -                  ~0ULL - ((1ULL << min(channels, slots)) - 1));
> +                  ~GENMASK_U32(min(channels, slots) - 1, 0));
> 
>       return 0;
>  }
> --
> 2.50.1


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