[U-Boot] [PATCH V2 1/6] dm: gpio: add a default gpio xlate routine

Stephen Warren
2016-04-11T17:16:33Z

On 04/11/2016 11:00 AM, Eric Nelson wrote:
> Many drivers use a common form of offset + flags for device
> tree nodes. e.g.:
> <&gpio1 2 GPIO_ACTIVE_LOW>
>
> This patch adds a common implementation of this type of parsing
> and calls it when a gpio driver doesn't supply its' own xlate
> routine.
>
> This will allow removal of the driver-specific versions in a
> handful of drivers and simplify the addition of new drivers.

The series,
Acked-by: Stephen Warren <swarren@nvidia.com>

Although one nit below.

> diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c

> +int gpio_xlate_offs_flags(struct udevice *dev,
> + struct gpio_desc *desc,
> + struct fdtdec_phandle_args *args)
> +{
> + int ret = -EINVAL;
> + if (args->args_count > 1) {
> + desc->offset = args->args[0];
> + if (args->args[1] & GPIO_ACTIVE_LOW)
> + desc->flags = GPIOD_ACTIVE_LOW;
> + ret = 0;
> + }
> + return ret;
> +}

Why not return the error first, and avoid the need for an extra
indentation level for the rest of the function, and make it quite a bit
more readable in my opinion. The default could also be made to cover
more situations (e.g. bindings that define a single cell for the GPIO
but not cell at all for any flags):

if (args->args_count < 1)
return -EINVAL;

desc->offset = args->args[0];

if (args->args_count < 2)
return 0;

if (args->args[1] & GPIO_ACTIVE_LOW)
desc->flags = GPIOD_ACTIVE_LOW;

return 0;