From adbc49a5a8c6fcf7be154c2e30213bbf472940da Mon Sep 17 00:00:00 2001 From: Devyn Liu Date: Mon, 13 May 2024 15:59:01 +0800 Subject: [PATCH] gpiolib: acpi: Fix failed in acpi_gpiochip_find() by adding parent node match 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. Fixes: 5062e4c14b75 ("gpiolib: acpi: use the fwnode in acpi_gpiochip_find()") Fixes: 067dbc1ea5ce ("gpiolib: acpi: Don't use GPIO chip fwnode in acpi_gpiochip_find()") Signed-off-by: Devyn Liu Reviewed-by: Mika Westerberg Tested-by: Benjamin Tissoires Signed-off-by: Andy Shevchenko --- drivers/gpio/gpiolib-acpi.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c index 8fb59864b58f..bb063b81cee6 100644 --- a/drivers/gpio/gpiolib-acpi.c +++ b/drivers/gpio/gpiolib-acpi.c @@ -128,7 +128,24 @@ static bool acpi_gpio_deferred_req_irqs_done; static int acpi_gpiochip_find(struct gpio_chip *gc, const void *data) { - return device_match_acpi_handle(&gc->gpiodev->dev, data); + /* First check the actual GPIO device */ + if (device_match_acpi_handle(&gc->gpiodev->dev, data)) + return true; + + /* + * When the ACPI device is artificially split to the banks of GPIOs, + * where each of them is represented by a separate GPIO device, + * the firmware node of the physical device may not be shared among + * the banks as they may require different values for the same property, + * e.g., number of GPIOs in a certain bank. In such case the ACPI handle + * of a GPIO device is NULL and can not be used. Hence we have to check + * the parent device to be sure that there is no match before bailing + * out. + */ + if (gc->parent) + return device_match_acpi_handle(gc->parent, data); + + return false; } /**