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SubjectRe: [PATCH v2] gpiolib: Show correct direction from the beginning
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Jeff, can you test these two patches on Amberwing to make sure that they 
don't cause an XPU violation on boot?

The call to gpiochip_line_is_valid() should return false on any GPIOs
that aren't listed in the ACPI table.

My concern is that this patch might be calling gpiochip_line_is_valid()
too early, before all the arrays have been set up.

Thanks.

On 9/21/18 5:36 AM, Ricardo Ribalda Delgado wrote:
> Current code assumes that the direction is input if direction_input
> function is set.
> This might not be the case on GPIOs with programmable direction.
>
> Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
> ---
> drivers/gpio/gpiolib.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index 4b45de883ada..00c17f64d9ff 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -1352,7 +1352,12 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
> * it does, and in case chip->get_direction is not set, we may
> * expose the wrong direction in sysfs.
> */
> - desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0;
> + if (chip->get_direction && gpiochip_line_is_valid(chip, i))
> + desc->flags = !chip->get_direction(chip, i) ?
> + (1 << FLAG_IS_OUT) : 0;
> + else
> + desc->flags = !chip->direction_input ?
> + (1 << FLAG_IS_OUT) : 0;
> }
>
> #ifdef CONFIG_PINCTRL
>

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