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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Wed, 11 Sep 2019 01:27:10 +0100
Message-ID: <CACRpkdbVC6DLHWftpL1wfkx_kWyfE=LpCQWZw=cv=RMVxDBm_g@mail.gmail.com>
Subject: Re: [PATCH] pinctrl: at91-pio4: implement .get_multiple and .set_multiple
To:     Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc:     Ludovic Desroches <ludovic.desroches@microchip.com>,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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On Thu, Sep 5, 2019 at 3:13 PM Alexandre Belloni
<alexandre.belloni@bootlin.com> wrote:
>
> Implement .get_multiple and .set_multiple to allow reading or setting
> multiple pins simultaneously. Pins in the same bank will all be switched at
> the same time, improving synchronization and performances.
>
> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Good initiative!

> +       for (bank = 0; bank < atmel_pioctrl->nbanks; bank++) {> +               unsigned int word = bank;
> +               unsigned int offset = 0;
> +               unsigned int reg;
> +
> +#if ATMEL_PIO_NPINS_PER_BANK != BITS_PER_LONG

Should it not be > rather than != ?

> +               word = BIT_WORD(bank * ATMEL_PIO_NPINS_PER_BANK);
> +               offset = bank * ATMEL_PIO_NPINS_PER_BANK % BITS_PER_LONG;
> +#endif

This doesn't look good for multiplatform kernels.

We need to get rid of any compiletime constants like this.

Not your fault I suppose it is already there, but this really need
to be fixed. Any ideas?

Yours,
Linus Walleij