Re: [PATCH v3 1/3] gpio: nct6116d: add new driver for several Nuvoton super io chips

From: Andy Shevchenko
Date: Tue Jul 12 2022 - 10:49:55 EST


On Tue, Jul 12, 2022 at 4:32 PM Henning Schild
<henning.schild@xxxxxxxxxxx> wrote:
>
> This patch adds gpio support for several Nuvoton NCTXXX chips. These
> Super-I/O chips offer multiple functions of which several already have
> drivers in the kernel, i.e. hwmon and watchdog.

...

> +#include <linux/gpio/driver.h>
> +#include <linux/init.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>

+ bits.h
+ types.h.

...

> +static inline int superio_enter(int base)
> +{
> + /* Don't step on other drivers' I/O space by accident. */
> + if (!request_muxed_region(base, 2, KBUILD_MODNAME)) {
> + pr_err("I/O address 0x%04x already in use\n", base);
> + return -EBUSY;
> + }
> +
> + /* According to the datasheet the key must be send twice. */

sent

> + outb(SIO_UNLOCK_KEY, base);
> + outb(SIO_UNLOCK_KEY, base);
> +
> + return 0;
> +}

...

> +#define gpio_dir(base) ((base) + 0)
> +#define gpio_data(base) ((base) + 1)

Dunno, why haven't you changed this? It might be a hidden mine for the
future GPIO library development. I recommend using namespace whenever
it feels right, and here it's exactly the case.

> + if (dir & 1 << offset)

Another ignored comment... BIT(offset)

I'm stopping here to let you double check what version you have sent.

--
With Best Regards,
Andy Shevchenko