Re: [PATCH 1/3] spi: mt65xx: Properly handle failures in .remove()

[AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>]

Il 09/03/23 10:47, Uwe Kleine-König ha scritto:
> Returning an error code in a platform driver's remove function is wrong
> most of the time and there is an effort to make the callback return
> void. To prepare this rework the function not to exit early.
> 
> There wasn't a real problem because if pm runtime resume failed the only
> step missing was pm_runtime_disable() which isn't an issue.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> ---
>   drivers/spi/spi-mt65xx.c | 21 +++++++++++++--------
>   1 file changed, 13 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c
> index 9eab6c20dbc5..b1cf7bbb2c08 100644
> --- a/drivers/spi/spi-mt65xx.c
> +++ b/drivers/spi/spi-mt65xx.c
> @@ -1275,15 +1275,20 @@ static int mtk_spi_remove(struct platform_device *pdev)
>   	struct mtk_spi *mdata = spi_master_get_devdata(master);
>   	int ret;
>   
> -	ret = pm_runtime_resume_and_get(&pdev->dev);
> -	if (ret < 0)
> -		return ret;
> -
> -	mtk_spi_reset(mdata);
> +	ret = pm_runtime_get_sync(&pdev->dev);

> +	/*
> +	 * If pm runtime resume failed, clks are disabled and unprepared. So
> +	 * don't access the hardware and skip clk unpreparing.
> +	 */

This comment is counter-intuitive: you're saying in words "if this failed" but
in code "if this didn't fail".

Please, either invert the branch so that it looks either like

/* if negative */
if (negative) warn
else /* positive */

or like

if (ret >= 0) {
	do_things()
} else {
	/* if it failed ... */
	warn
}

Functionally, though, looks good to me.

Cheers,
Angelo