Re: [PATCH v9 3/5] pwm: sun8i: export the bypass outputs as clocks

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] clk: missing args_count validation in sun8i_pwm_get_clk_hw() reads uninitialized memory
--

commit 68e6d29bee94ba15c085b933d17a7299032ead6b
Author: Richard Genoud <richard.genoud@bootlin.com>

pwm: sun8i: export the bypass outputs as clocks

This commit exposes each H616 PWM channel's hardware bypass as a CCF clock
for consumers that need a clock rather than PWM duty control. It arbitrates
ownership between PWM requests and clock prepare, using CLK_IGNORE_UNUSED
to preserve unclaimed bypass outputs.

> diff --git a/drivers/pwm/pwm-sun8i.c b/drivers/pwm/pwm-sun8i.c
> index 7e6c39815c183..fd81c5f5e3267 100644
> --- a/drivers/pwm/pwm-sun8i.c
> +++ b/drivers/pwm/pwm-sun8i.c

[ ... ]

> @@ -1012,6 +1169,17 @@ sun8i_pwm_sanitize_disabled_pairs(struct sun8i_pwm_chip *sun8i_chip)
>  	sun8i_pwm_writel(sun8i_chip, per, SUN8I_PWM_PER);
>  }
>  
> +static struct clk_hw *sun8i_pwm_get_clk_hw(struct of_phandle_args *clkspec,
> +					   void *data)
> +{
> +	struct sun8i_pwm_chip *sun8i_chip = data;
> +
> +	if (clkspec->args[0] >= SUN8I_PWM_NPWM)

[Severity: Medium]
Is it possible to read uninitialized memory here if the device tree is
incorrectly configured? 

If a consumer device requests a clock from this provider but specifies zero
clock cells (#clock-cells = <0>), of_parse_phandle_with_args() might leave
the args array uninitialized.

Should this code verify clkspec->args_count >= 1 before accessing
clkspec->args[0]?

> +		return ERR_PTR(-EINVAL);
> +
> +	return &sun8i_chip->channels[clkspec->args[0]].bypass_hw;
> +}
> +
>  static int sun8i_pwm_probe(struct platform_device *pdev)

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260921-h616-pwm-v8-v9-0-37bec6201ff5@gmail.com?part=3