For platforms that use device tree or ACPI as the standard way to look GPIOs up, allow the platform-defined GPIO mappings to be used as a fallback. This may be useful for platforms that need extra GPIOs mappings not defined by the firmware.
Signed-off-by: Alexandre Courbot <[email protected]> --- drivers/gpio/gpiolib.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 86caf17..4edd68c 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -2417,7 +2417,7 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev, const char *con_id, unsigned int idx) { - struct gpio_desc *desc; + struct gpio_desc *desc = NULL; int status; enum gpio_lookup_flags flags = 0; @@ -2430,9 +2430,19 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev, } else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) { dev_dbg(dev, "using ACPI for GPIO lookup\n"); desc = acpi_find_gpio(dev, con_id, idx, &flags); - } else { + } + + /* + * Either we are not using DT or ACPI, or their lookup did not return + * a result. In that case, use platform lookup as a fallback. + */ + if (!desc || IS_ERR(desc)) { + struct gpio_desc *pdesc; dev_dbg(dev, "using lookup tables for GPIO lookup"); - desc = gpiod_find(dev, con_id, idx, &flags); + pdesc = gpiod_find(dev, con_id, idx, &flags); + /* If used as fallback, do not replace the previous error */ + if (!IS_ERR(pdesc) || !desc) + desc = pdesc; } if (IS_ERR(desc)) { -- 1.8.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
