Re: [PATCH] gpio: pca953x: fix gpio input on gpio offsets >= 8

[Gregory CLEMENT <gregory.clement@free-electrons.com>]

On 07/08/2013 23:52, Andrew Ruder wrote:
> This change fixes a regression introduced by commit
> f5f0b7aa8 (gpio: pca953x: make the register access by GPIO bank)
> 
> When the pca953x driver was converted to using 8-bit reads/writes
> the bitmask in pca953x_gpio_get_value wasn't adjusted with a
> modulus BANK_SZ and consequently looks at the wrong bits in the
> input register.

Good catch. I forgot this one and as on my board I wasn't able to
test the input I didn't noticed it.
Thanks

Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>


> 
> Signed-off-by: Andrew Ruder <andrew.ruder@elecsyscorp.com>
> ---
> 
>  drivers/gpio/gpio-pca953x.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
> index 426c51d..1a7ab13 100644
> --- a/drivers/gpio/gpio-pca953x.c
> +++ b/drivers/gpio/gpio-pca953x.c
> @@ -308,7 +308,7 @@ static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
>  		return 0;
>  	}
>  
> -	return (reg_val & (1u << off)) ? 1 : 0;
> +	return (reg_val & (1u << (off % BANK_SZ))) ? 1 : 0;
>  }
>  
>  static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
> 


-- 
Gregory Clement, Free Electrons
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