Re: [PATCH v2] serial: 8250_dw: handle reset control deassert error

[Greg KH <gregkh@linuxfoundation.org>]

On Sun, Oct 19, 2025 at 11:53:25AM +0300, Artem Shimko wrote:
> Check the return value of reset_control_deassert() in the probe
> function to prevent continuing probe when reset deassertion fails.
> 
> Previously, reset_control_deassert() was called without checking its
> return value, which could lead to probe continuing even when the
> device reset wasn't properly deasserted.
> 
> The fix checks the return value and returns an error with dev_err_probe()
> if reset deassertion fails, providing better error handling and
> diagnostics.
> 
> Fixes: acbdad8dd1ab ("serial: 8250_dw: simplify optional reset handling")
> Signed-off-by: Artem Shimko <a.shimko.dev@gmail.com>
> ---
> Hi Andy,
> 
> Thank you for your review.
> 
> The v1 patch hasn't been applied.
> 
> I've addressed your comments in v2 - could you please take a look when you have time?
> 
> Best regards,
> Artem Shimko
> 
> ChangeLog:
>   v1:
>     * https://lore.kernel.org/all/20251009081309.2021600-1-a.shimko.dev@gmail.com/T/#u
>   v2:
>     * Add fix tag to commit description
> 
>  drivers/tty/serial/8250/8250_dw.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
> index a53ba04d9770..710ae4d40aec 100644
> --- a/drivers/tty/serial/8250/8250_dw.c
> +++ b/drivers/tty/serial/8250/8250_dw.c
> @@ -635,7 +635,9 @@ static int dw8250_probe(struct platform_device *pdev)
>  	if (IS_ERR(data->rst))
>  		return PTR_ERR(data->rst);
>  
> -	reset_control_deassert(data->rst);
> +	err = reset_control_deassert(data->rst);
> +	if (err)
> +		return dev_err_probe(dev, err, "failed to deassert resets\n");
>  
>  	err = devm_add_action_or_reset(dev, dw8250_reset_control_assert, data->rst);
>  	if (err)
> -- 
> 2.43.0
> 
> 

Hi,

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