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References: <20221107135825.583877-1-herve.codina@bootlin.com> <20221107135825.583877-2-herve.codina@bootlin.com>
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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Mon, 7 Nov 2022 15:40:53 +0100
Message-ID: <CAMuHMdVbWGYPkspMx40S02cr6sX2LZkGwye3JQCtiPtLhuDCPw@mail.gmail.com>
Subject: Re: [PATCH 1/7] soc: renesas: r9a06g032-sysctrl: Export function to
 get H2MODE from CFG_USB register
To:     Herve Codina <herve.codina@bootlin.com>
Cc:     Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Magnus Damm <magnus.damm@gmail.com>,
        Gareth Williams <gareth.williams.jx@renesas.com>,
        linux-renesas-soc@vger.kernel.org, linux-clk@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-usb@vger.kernel.org,
        Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
        Miquel Raynal <miquel.raynal@bootlin.com>
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Hi Hervé,

On Mon, Nov 7, 2022 at 2:59 PM Herve Codina <herve.codina@bootlin.com> wrote:
> The CFG_USB register is located within the system controller.
>
> We need a helper to get the H2MODE value from the CFG_USB register
> without syscon.
>
> Signed-off-by: Herve Codina <herve.codina@bootlin.com>

> --- a/drivers/clk/renesas/r9a06g032-clocks.c
> +++ b/drivers/clk/renesas/r9a06g032-clocks.c
> @@ -25,6 +25,8 @@
>  #include <linux/spinlock.h>
>  #include <dt-bindings/clock/r9a06g032-sysctrl.h>
>
> +#define R9A06G032_SYSCTRL_USB    0x00
> +#define R9A06G032_SYSCTRL_USB_H2MODE  (1<<1)
>  #define R9A06G032_SYSCTRL_DMAMUX 0xA0
>
>  struct r9a06g032_gate {
> @@ -341,6 +343,22 @@ int r9a06g032_sysctrl_set_dmamux(u32 mask, u32 val)
>  }
>  EXPORT_SYMBOL_GPL(r9a06g032_sysctrl_set_dmamux);
>
> +
> +/* Exported helper to get the H2MODE bit from USB register */
> +int r9a06g032_sysctrl_get_usb_h2mode(bool *h2mode)
> +{
> +       u32 usb;
> +
> +       if (!sysctrl_priv)
> +               return -EPROBE_DEFER;
> +
> +       usb = readl(sysctrl_priv->reg + R9A06G032_SYSCTRL_USB);
> +       *h2mode = (usb & R9A06G032_SYSCTRL_USB_H2MODE) ? true : false;
> +
> +       return 0;

Perhaps not pass *h2mode, but just return USB_ROLE_{HOST,DEVICE}
(enum usb_role in <linux/usb/role.h>), or a negative error code?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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