Re: [PATCH v6 07/11] ASoC: renesas: fsi: Use devm_clk_get_optional() for optional clocks

[sashiko-bot@kernel.org]

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

Pre-existing issues:
- [High] fsi_clk_enable() returns -EINVAL when called on an already enabled clock, breaking full-duplex operation.
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commit e751270870bfce8cae5b9b1175c1bc9e265d605e
Author: bui duc phuc <phucduc.bui@gmail.com>

ASoC: renesas: fsi: Use devm_clk_get_optional() for optional clocks

The xck, ick, and div clocks are optional. Switch from devm_clk_get()
to devm_clk_get_optional() to correctly handle cases where these clocks
are missing.

> diff --git a/sound/soc/renesas/fsi.c b/sound/soc/renesas/fsi.c
> index 1df7dc0143630..e29be2bcf952c 100644
> --- a/sound/soc/renesas/fsi.c
> +++ b/sound/soc/renesas/fsi.c
> @@ -994,7 +994,7 @@ static int fsi_clk_init(struct device *dev,
>  
>  	/* external clock */
>  	if (xck) {
> -		clock->xck = devm_clk_get(dev, is_porta ? "xcka" : "xckb");
> +		clock->xck = devm_clk_get_optional(dev, is_porta ? "xcka" : "xckb");
>  		if (IS_ERR(clock->xck)) {
>  			dev_err(dev, "can't get xck clock\n");
>  			return -EINVAL;

[Severity: High]
This isn't a bug introduced by this patch, but while reviewing these
clock changes, I noticed a pre-existing issue in fsi_clk_enable().

sound/soc/renesas/fsi.c:fsi_clk_enable() {
	struct fsi_clk *clock = &fsi->clock;
	int ret = -EINVAL;

	if (!fsi_clk_is_valid(fsi))
		return ret;

	if (0 == clock->count) {
		...
		clock->count++;
	}

	return ret;
}

When a second stream starts on the same port (for example, capture starting
while playback is already running), count is 1. The code skips the
(0 == clock->count) block and returns the initial ret value of -EINVAL.

Does this break full-duplex operation by causing fsi_hw_startup() to fail
when starting the second stream?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260609113836.45079-1-phucduc.bui@gmail.com?part=7