Re: [PATCH 7/7] usb: musb: convert to devm_platform_ioremap_resource_byname

[Geert Uytterhoeven]

Hi Chunfeng,

On Wed, Jul 22, 2020 at 9:54 AM Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> wrote:
> Use devm_platform_ioremap_resource_byname() to simplify code
>
> Cc: Bin Liu <b-liu@xxxxxx>
> Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>

Thanks for your patch, which is now commit 2d30e408a2a6b344 ("usb: musb:
convert to devm_platform_ioremap_resource_byname") in v5.9.

> --- a/drivers/usb/musb/musb_dsps.c
> +++ b/drivers/usb/musb/musb_dsps.c
> @@ -429,12 +429,10 @@ static int dsps_musb_init(struct musb *musb)
>         struct platform_device *parent = to_platform_device(dev->parent);
>         const struct dsps_musb_wrapper *wrp = glue->wrp;
>         void __iomem *reg_base;
> -       struct resource *r;
>         u32 rev, val;
>         int ret;
>
> -       r = platform_get_resource_byname(parent, IORESOURCE_MEM, "control");
> -       reg_base = devm_ioremap_resource(dev, r);
> +       reg_base = devm_platform_ioremap_resource_byname(parent, "control");
>         if (IS_ERR(reg_base))
>                 return PTR_ERR(reg_base);
>         musb->ctrl_base = reg_base;

On Beaglebone Black, where each interface has 2 children:

    musb-dsps 47401c00.usb: can't request region for resource [mem
0x47401800-0x474019ff]
    musb-hdrc musb-hdrc.1: musb_init_controller failed with status -16
    musb-hdrc: probe of musb-hdrc.1 failed with error -16
    musb-dsps 47401400.usb: can't request region for resource [mem
0x47401000-0x474011ff]
    musb-hdrc musb-hdrc.0: musb_init_controller failed with status -16
    musb-hdrc: probe of musb-hdrc.0 failed with error -16

Before, devm_ioremap_resource() was called on "dev" ("musb-hdrc.0" or
"musb-hdrc.1"), after it is called on "&pdev->dev" ("47401400.usb" or
"47401c00.usb"), leading to a duplicate region request, which fails.

I have sent a revert:
https://lore.kernel.org/linux-usb/20201112135900.3822599-1-geert+renesas@xxxxxxxxx/

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds