On Tue, May 6, 2025 at 6:21 PM Thomas Richard
<[email protected]> wrote:
>
> Add request() callback to check if the GPIO descriptor was well registered
> in the gpiochip_fwd before using it. This is done to handle the case where
> GPIO descriptor is added at runtime in the forwarder.
>
> If at least one GPIO descriptor was not added before the forwarder
> registration, we assume the forwarder can sleep as if a GPIO is added at
> runtime it may sleep.
...
> {
> struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
>
> + /*
> + * get_direction() is called during gpiochip registration, return
> input
> + * direction if there is no descriptor for the line.
> + */
> + if (!test_bit(offset, fwd->valid_mask))
> + return GPIO_LINE_DIRECTION_IN;
Can you remind me why we choose a valid return for invalid line? From
a pure code perspective this should return an error.
> return gpiod_get_direction(fwd->descs[offset]);
> }
...
> + /*
> + * Some gpio_desc were not registered. They will be registered at
> runtime
> + * but we have to suppose they can sleep.
suppose --> assume ?
> + */
> + if (!bitmap_full(fwd->valid_mask, chip->ngpio))
> + chip->can_sleep = true;
--
With Best Regards,
Andy Shevchenko
