Re: [PATCH] gpio: omap: handle clk_prepare failure in probe

[Andreas Kemnade]

On Tue, 18 Aug 2026 17:08:54 +0400
Jiawen Liu <1298662399@xxxxxx> wrote:

> omap_gpio_probe() ignores the return value of clk_prepare(bank->dbck).
> If clk_prepare fails, the clock is not prepared, but bank->dbck_flag
> remains true. Later, omap_gpio_remove() or the probe error path calls
> clk_unprepare(bank->dbck) unconditionally when dbck_flag is true,
> leading to an unbalanced clock operation.
> 
> Check the return value of clk_prepare in omap_gpio_probe. On failure,
> clear dbck_flag and return the error, preventing unbalanced
> clk_unprepare in remove or error paths.
> 
> Signed-off-by: jiawen <1298662399@xxxxxx>
> ---
> diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
> --- a/drivers/gpio/gpio-omap.c
> +++ b/drivers/gpio/gpio-omap.c
> @@ -1462,7 +1462,12 @@
>  				"Could not get gpio dbck. Disable debounce\n");
>  			bank->dbck_flag = false;
>  		} else {
> -			clk_prepare(bank->dbck);
> +			ret = clk_prepare(bank->dbck);
> +			if (ret) {
> +				dev_err(dev, "Could not prepare gpio dbck\n");
> +				bank->dbck_flag = false;
> +				return ret;
> +			}
>
What about simply using devm_clk_get_prepared() here? That would simplify
things a lot, given that AFAIK,  prepare is a no-op here anyways.

Regards,
Andreas