Re: [PATCH 1/2] MIPS/input: Move RB532 button to GPIO descriptors

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

Hi Linus,

On Sat, Mar 28, 2026 at 04:55:47PM +0100, Linus Walleij wrote:
> Convert the Mikrotik RouterBoard RB532 to use GPIO descriptors
> by defining a software node for the GPIO chip, then register
> the button platform device with full info passing the GPIO
> as a device property.
> 
> This can be used as a base to move more of the RB532 devices
> over to passing GPIOs using device properties.
> 
> Use the GPIO_ACTIVE_LOW flag and drop the inversion in the
> rb532_button_pressed() function.
> 
> Signed-off-by: Linus Walleij <linusw@kernel.org>
> ---
>  arch/mips/rb532/devices.c         | 47 +++++++++++++++++++++++++++++++++------
>  drivers/input/misc/rb532_button.c | 35 ++++++++++++++++++++++++-----
>  2 files changed, 69 insertions(+), 13 deletions(-)
> 
> diff --git a/arch/mips/rb532/devices.c b/arch/mips/rb532/devices.c
> index 4f027efbf27b..3f56d9feb73a 100644
> --- a/arch/mips/rb532/devices.c
> +++ b/arch/mips/rb532/devices.c
> @@ -16,8 +16,10 @@
>  #include <linux/mtd/mtd.h>
>  #include <linux/gpio.h>
>  #include <linux/gpio/machine.h>
> +#include <linux/gpio/property.h>
>  #include <linux/gpio_keys.h>
>  #include <linux/input.h>
> +#include <linux/property.h>
>  #include <linux/serial_8250.h>
>  
>  #include <asm/bootinfo.h>
> @@ -38,6 +40,10 @@ extern unsigned int idt_cpu_freq;
>  
>  static struct mpmc_device dev3;
>  
> +static const struct software_node rb532_gpio0_node = {
> +	.name = "gpio0",
> +};

You need to move this and registration into arch/mips/rb532/gpio.c,
export it and use it here: Bartosz is against using gpiohip label to
match with software node name and prefers identity matching.

...

> -static bool rb532_button_pressed(void)
> +static bool rb532_button_pressed(struct rb532_button *button)
>  {
>  	int val;
>  
>  	set_latch_u5(0, LO_FOFF);
> -	gpio_direction_input(GPIO_BTN_S1);
> +	gpiod_direction_input(button->gpio);
>  
> -	val = gpio_get_value(GPIO_BTN_S1);
> +	val = gpiod_get_value(button->gpio);
>  
>  	rb532_gpio_set_func(GPIO_BTN_S1);
>  	set_latch_u5(LO_FOFF, 0);
>  
> -	return !val;
> +	return val;
>  }

I suppose there is no reasonable way of making this work with
gpio-keys...

For input piece:

Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Thanks.

-- 
Dmitry