Re: [PATCH v2 7/7] ASoC: codecs: ES8389: Add INPUTL MUX and INPUTR MUX

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] Logic error in get_coeff incorrectly treats 0 as a wildcard for dmic_sel and dvdd_vol, shadowing specific coefficient configurations.
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commit 6402e3af14ba28c3424e8a95b28fe5d44fa00f37
Author: Zhang Yi <zhangyi@everest-semi.com>

ASoC: codecs: ES8389: Add INPUTL MUX and INPUTR MUX

This commit adds INPUTL MUX and INPUTR MUX to the DAPM routing paths for
the ES8389 codec.

> diff --git a/sound/soc/codecs/es8389.c b/sound/soc/codecs/es8389.c
> index bcec9d9200dbe..294951d49432c 100644
> --- a/sound/soc/codecs/es8389.c
> +++ b/sound/soc/codecs/es8389.c

[ ... ]

[Severity: High]
This isn't a bug introduced by this patch, but looking at get_coeff() in
sound/soc/codecs/es8389.c, is there a logic error with how dmic_sel and
dvdd_vol are checked?

sound/soc/codecs/es8389.c:get_coeff() {
	...
	for (i = 0; i < ARRAY_SIZE(coeff_div); i++) {
		if (coeff_div[i].rate == rate && coeff_div[i].mclk == mclk) {
			vddd_det = ~(coeff_div[i].dvdd_vol ^ vddd) & 0x01;
			dmic_det = ~(coeff_div[i].dmic_sel ^ dmic) & 0x01;
			vddd_det |= ~(coeff_div[i].dvdd_vol % 2) & 0x01;
			dmic_det |= ~(coeff_div[i].dmic_sel % 2) & 0x01;

			if (vddd_det && dmic_det)
				return i;
		}
	}
	...
}

Because ~(0 % 2) & 0x01 evaluates to 1, doesn't this calculation cause 0 to
act as a wildcard, evaluating to true regardless of the dmic or vddd
parameters?

If entries with dmic_sel = 0 appear before dmic_sel = 1 in the coeff_div
table, could get_coeff() prematurely return the wildcard match?  This appears
to make the correct clock coefficient entries for dmic = 1 dead code,
potentially resulting in incorrect clock configurations.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260618082842.2778-1-zhangyi@everest-semi.com?part=7