From: Andy Shevchenko andriy.shevchenko@linux.intel.com
commit b41ba2ec54a70908067034f139aa23d0dd2985ce upstream.
On STM32MP1, the GPIO banks are subnodes of pin-controller@50002000, see arch/arm/boot/dts/stm32mp151.dtsi. The driver for pin-controller@50002000 is in drivers/pinctrl/stm32/pinctrl-stm32.c and iterates over all of its DT subnodes when registering each GPIO bank gpiochip. Each gpiochip has:
- gpio_chip.parent = dev, where dev is the device node of the pin controller - gpio_chip.of_node = np, which is the OF node of the GPIO bank
Therefore, dev_fwnode(chip->parent) != of_fwnode_handle(chip.of_node), i.e. pin-controller@50002000 != pin-controller@50002000/gpio@5000*000.
The original code behaved correctly, as it extracted the "gpio-line-names" from of_fwnode_handle(chip.of_node) = pin-controller@50002000/gpio@5000*000.
To achieve the same behaviour, read property from the firmware node.
Fixes: 7cba1a4d5e162 ("gpiolib: generalize devprop_gpiochip_set_names() for device properties") Reported-by: Marek Vasut marex@denx.de Reported-by: Roman Guskov rguskov@dh-electronics.com Signed-off-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Tested-by: Marek Vasut marex@denx.de Reviewed-by: Marek Vasut marex@denx.de Signed-off-by: Bartosz Golaszewski bgolaszewski@baylibre.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpio/gpiolib.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-)
--- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -364,22 +364,18 @@ static int gpiochip_set_desc_names(struc * * Looks for device property "gpio-line-names" and if it exists assigns * GPIO line names for the chip. The memory allocated for the assigned - * names belong to the underlying software node and should not be released + * names belong to the underlying firmware node and should not be released * by the caller. */ static int devprop_gpiochip_set_names(struct gpio_chip *chip) { struct gpio_device *gdev = chip->gpiodev; - struct device *dev = chip->parent; + struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev); const char **names; int ret, i; int count;
- /* GPIO chip may not have a parent device whose properties we inspect. */ - if (!dev) - return 0; - - count = device_property_string_array_count(dev, "gpio-line-names"); + count = fwnode_property_string_array_count(fwnode, "gpio-line-names"); if (count < 0) return 0;
@@ -393,7 +389,7 @@ static int devprop_gpiochip_set_names(st if (!names) return -ENOMEM;
- ret = device_property_read_string_array(dev, "gpio-line-names", + ret = fwnode_property_read_string_array(fwnode, "gpio-line-names", names, count); if (ret < 0) { dev_warn(&gdev->dev, "failed to read GPIO line names\n");