Re: [RFC PATCH v4 net-next 11/23] pinctrl: ocelot: update pinctrl to automatic base address

[Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>]

Hello,

On 15/11/2021 22:23:16-0800, Colin Foster wrote:
> struct gpio_chip recommends passing -1 as base to gpiolib. Doing so avoids
> conflicts when the chip is external and gpiochip0 already exists.
> 
> Signed-off-by: Colin Foster <colin.foster@xxxxxxxxxxxxxxxx>
> ---
>  drivers/pinctrl/pinctrl-ocelot.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pinctrl/pinctrl-ocelot.c b/drivers/pinctrl/pinctrl-ocelot.c
> index cc7fb0556169..f015404c425c 100644
> --- a/drivers/pinctrl/pinctrl-ocelot.c
> +++ b/drivers/pinctrl/pinctrl-ocelot.c
> @@ -1308,7 +1308,7 @@ static int ocelot_gpiochip_register(struct platform_device *pdev,
>  	gc = &info->gpio_chip;
>  	gc->ngpio = info->desc->npins;
>  	gc->parent = &pdev->dev;
> -	gc->base = 0;
> +	gc->base = -1;

I can't remember why but I'm pretty sure I did that on purpose but this
indeed cause issues when the chip is external. I've asked Clément to
check, let's see what the result is ;)

>  	gc->of_node = info->dev->of_node;
>  	gc->label = "ocelot-gpio";
>  
> -- 
> 2.25.1
> 

-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com