• Devyn Liu's avatar
    gpiolib: acpi: Fix failed in acpi_gpiochip_find() by adding parent node match · adbc49a5
    Devyn Liu authored
    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: 5062e4c1 ("gpiolib: acpi: use the fwnode in acpi_gpiochip_find()")
    Fixes: 067dbc1e ("gpiolib: acpi: Don't use GPIO chip fwnode in acpi_gpiochip_find()")
    Signed-off-by: default avatarDevyn Liu <liudingyuan@huawei.com>
    Reviewed-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
    Tested-by: default avatarBenjamin Tissoires <bentiss@kernel.org>
    Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
    adbc49a5
gpiolib-acpi.c 45.9 KB