Re: [PATCH] ASoC: SOF: imx: Fix devm_ioremap_resource check

[Dan Carpenter]

On Mon, Sep 01, 2025 at 06:15:13PM +0300, Daniel Baluta wrote:
> devm_ioremap_resource does not return NULL on error
> but an error pointer so we need to use IS_ERR to check
> the return code.
> 
> Fixes: bc163baef570 ("ASoC: Use of_reserved_mem_region_to_resource() for "memory-region"")
> Signed-off-by: Daniel Baluta <daniel.baluta@xxxxxxx>
> ---
>  sound/soc/sof/imx/imx-common.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/sound/soc/sof/imx/imx-common.c b/sound/soc/sof/imx/imx-common.c
> index 40debc541bf9..b3248c65215d 100644
> --- a/sound/soc/sof/imx/imx-common.c
> +++ b/sound/soc/sof/imx/imx-common.c
> @@ -316,7 +316,7 @@ static int imx_parse_ioremap_memory(struct snd_sof_dev *sdev)
>  		}
>  
>  		sdev->bar[blk_type] = devm_ioremap_resource(sdev->dev, res);
> -		if (!sdev->bar[blk_type])
> +		if (IS_ERR(sdev->bar[blk_type]))
>  			return dev_err_probe(sdev->dev,
>  					     -ENOMEM,

It's annoying that I didn't catch this bug.  It's because the error
pointer was stored in an array instead of a a "simple" variable.
Smatch does actually have a lower quality warning for this but I
wasn't reviewing them since that check had too many false positives.

I've done a little hack around, so this bug will be caught in the
future and it found a few other similar bugs which I've fixed as well.

regards,
dan carpenter