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| author | Stefan Wahren <stefan.wahren@i2se.com> | 2022-04-09 11:51:28 +0200 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2022-04-21 16:12:07 +0200 |
| commit | 3550bba25d5587a701e6edf20e20984d2ee72c78 (patch) | |
| tree | 8d47bfb95de5331e430c149504456208c856f790 | |
| parent | 1a08cb7303cfd898cb9b5c5b1a185e7ed329919f (diff) | |
| download | linux-stable-3550bba25d5587a701e6edf20e20984d2ee72c78.tar.gz linux-stable-3550bba25d5587a701e6edf20e20984d2ee72c78.tar.bz2 linux-stable-3550bba25d5587a701e6edf20e20984d2ee72c78.zip | |
gpiolib: of: Introduce hook for missing gpio-ranges
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>
Link: https://lore.kernel.org/r/20220409095129.45786-2-stefan.wahren@i2se.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
| -rw-r--r-- | drivers/gpio/gpiolib-of.c | 5 | ||||
| -rw-r--r-- | include/linux/gpio/driver.h | 12 |
2 files changed, 17 insertions, 0 deletions
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index ae1ce319cd78..d9b235c88b54 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -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++) { diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index 98c93510640e..c2041bd01f90 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -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 */ }; |