Re: [PATCH v1] mfd: syscon: Switch to use devm_ioremap_resource()

[Arnd Bergmann]

On Fri, Jan 10, 2020 at 11:15 AM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
>
> Instead of checking resource pointer for being NULL and
> report some not very standard error codes in this case,
> switch to devm_ioremap_resource() API.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

With syscon, I'm worried there are users that map the same region in another
driver, so doing devm_ioremap_resource() here will make another driver fail.

Maybe just change the error code and add a comment warning about that
instead?

      Arnd

> diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
> index 13626bb2d432..fad961b2e4a5 100644
> --- a/drivers/mfd/syscon.c
> +++ b/drivers/mfd/syscon.c
> @@ -238,12 +238,9 @@ static int syscon_probe(struct platform_device *pdev)
>                 return -ENOMEM;
>
>         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> -       if (!res)
> -               return -ENOENT;
> -
> -       base = devm_ioremap(dev, res->start, resource_size(res));
> -       if (!base)
> -               return -ENOMEM;
> +       base = devm_ioremap_resource(dev, res);
> +       if (IS_ERR(base))
> +               return PTR_ERR(base);