@@ -931,6 +931,11 @@ static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
if (!np)
return 0;
+ if (!of_property_read_bool(np, "gpio-ranges") &&
+ chip->of_gpio_ranges_fallback) {
+ return chip->of_gpio_ranges_fallback(chip, np);
+ }
+
group_names = of_find_property(np, group_names_propname, NULL);
for (;; index++) {
@@ -492,6 +492,18 @@ struct gpio_chip {
*/
int (*of_xlate)(struct gpio_chip *gc,
const struct of_phandle_args *gpiospec, u32 *flags);
+
+ /**
+ * @of_gpio_ranges_fallback
+ *
+ * Optional hook for the case that no gpio-ranges property is defined
+ * within the device tree node "np" (usually DT before introduction
+ * of gpio-ranges). So this callback is helpful to provide the
+ * necessary backward compatibility for the pin ranges.
+ */
+ int (*of_gpio_ranges_fallback)(struct gpio_chip *gc,
+ struct device_node *np);
+
#endif /* CONFIG_OF_GPIO */
};
Since commit 2ab73c6d8323 ("gpio: Support GPIO controllers without pin-ranges") the device tree nodes of GPIO controller need the gpio-ranges property to handle gpio-hogs. Unfortunately it's impossible to guarantee that every new kernel is shipped with an updated device tree binary. In order to provide backward compatibility with those older DTB, we need a callback within of_gpiochip_add_pin_range() so the relevant platform driver can handle this case. Fixes: 2ab73c6d8323 ("gpio: Support GPIO controllers without pin-ranges") Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Tested-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Bartosz Golaszewski <brgl@bgdev.pl> --- drivers/gpio/gpiolib-of.c | 5 +++++ include/linux/gpio/driver.h | 12 ++++++++++++ 2 files changed, 17 insertions(+)