Re: [PATCH v2 2/2] gpiolib: check the 'ngpios' property in core gpiolib code

From: Andy Shevchenko
Date: Thu Nov 18 2021 - 10:46:34 EST


On Thu, Nov 18, 2021 at 02:23:17PM +0100, Bartosz Golaszewski wrote:
> Several drivers read the 'ngpios' device property on their own, but
> since it's defined as a standard GPIO property in the device tree bindings
> anyway, it's a good candidate for generalization. If the driver didn't
> set its gc->ngpio, try to read the 'ngpios' property from the GPIO
> device's firmware node before bailing out.

Thanks for update, my comment below.

...

> if (gc->ngpio == 0) {
> - chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
> - ret = -EINVAL;
> - goto err_free_descs;
> + ret = device_property_read_u32(&gdev->dev, "ngpios", &ngpios);
> + if (ret) {
> + chip_err(gc, "tried to insert a GPIO chip with zero lines\n");

> + ret = -EINVAL;

Sorry, forgot to ask, why this is needed?

> + goto err_free_descs;
> + }
> +
> + gc->ngpio = ngpios;
> }

--
With Best Regards,
Andy Shevchenko