On Mon, May 13, 2024 at 03:59:01PM +0800, Devyn Liu wrote:
> Previous patch modified the standard used by acpi_gpiochip_find()
> to match device nodes. Using the device node set in gc->gpiodev->d-
> ev instead of gc->parent.
>
> However, there is a situation in gpio-dwapb where the GPIO device
> driver will set gc->fwnode for each port corresponding to a child
> node under a GPIO device, so gc->gpiodev->dev will be assigned the
> value of each child node in gpiochip_add_data().
>
> gpio-dwapb.c:
> 128,31 static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
> struct dwapb_port_property *pp,
> unsigned int offs);
> port->gc.fwnode = pp->fwnode;
>
> 693,39 static int dwapb_gpio_probe;
> err = dwapb_gpio_add_port(gpio, &pdata->properties[i], i);
>
> When other drivers request GPIO pin resources through the GPIO device
> node provided by ACPI (corresponding to the parent node), the change
> of the matching object to gc->gpiodev->dev in acpi_gpiochip_find()
> only allows finding the value of each port (child node), resulting
> in a failed request.
>
> Reapply the condition of using gc->parent for match in acpi_gpio-
> chip_find() in the code can compatible with the problem of gpio-dwapb,
> and will not affect the two cases mentioned in the patch:
> 1. There is no setting for gc->fwnode.
> 2. The case that depends on using gc->fwnode for match.
Thanks for the report, analysis, and patch.
...
> static int acpi_gpiochip_find(struct gpio_chip *gc, const void *data)
> {
> - return device_match_acpi_handle(&gc->gpiodev->dev, data);
> + return device_match_acpi_handle(&gc->gpiodev->dev, data) ||
> + (gc->parent && device_match_acpi_handle(gc->parent, data));
> }
I'm wondering if the below approach will work for all:
static int acpi_gpiochip_find(struct gpio_chip *gc, const void *data)
{
struct device *dev = acpi_get_first_physical_node(ACPI_COMPANION(&gc->gpiodev->dev));
return device_match_acpi_handle(dev, data);
}
Cc'ing to Benjamin for testing and commenting.
--
With Best Regards,
Andy Shevchenko
