Re: [PATCH 1/3] serial: mxs-auart: rework clock handling in mxs_get_clks and probe

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Unconditional execution of `clk_prepare_enable(s->clk)` in `probe()` causes a clock enable leak and power regression for non-ASM9260 devices. Note: I found the fix later in the series in patch "serial: mxs-auart: fix IRQ registration ordering and manage console clock".
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commit 6dcd08fa908a611decc8b93570ddfa7ca65af26c
Author: Rosen Penev <rosenp@gmail.com>

serial: mxs-auart: rework clock handling in mxs_get_clks and probe

This commit reworks clock handling by moving the mod clock enable into probe
to avoid CLK_SET_RATE_GATE failures and uses devm_clk_get_enabled for the
AHB clock.

> diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
> index 693b491f1e755..8d050ceb72d2f 100644
> --- a/drivers/tty/serial/mxs-auart.c
> +++ b/drivers/tty/serial/mxs-auart.c
[ ... ]
> @@ -1604,17 +1592,21 @@ static int mxs_auart_probe(struct platform_device *pdev)
>  	if (ret)
>  		return ret;
>  
> +	ret = clk_prepare_enable(s->clk);
> +	if (ret)
> +		return ret;
> +
[ ... ]
> @@ -1697,10 +1686,8 @@ static void mxs_auart_remove(struct platform_device *pdev)
>  	auart_port[pdev->id] = NULL;
>  	mxs_auart_free_gpio_irq(s);
>  	iounmap(s->port.membase);
> -	if (is_asm9260_auart(s)) {
> +	if (is_asm9260_auart(s))
>  		clk_disable_unprepare(s->clk);
> -		clk_disable_unprepare(s->clk_ahb);
> -	}
>  }

[Severity: Medium]
Since clk_prepare_enable(s->clk) is now called unconditionally in probe for
all device variants, does keeping the is_asm9260_auart(s) check here cause
a clock enable reference leak for non-ASM9260 hardware when the device is
removed?

I noted that this is fixed later in the series by the patch "serial:
mxs-auart: fix IRQ registration ordering and manage console clock", but
would this intermediate step break bisectability by introducing a temporary
leak?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260603025857.287148-1-rosenp@gmail.com?part=1