gpio: Handle deferred probing in of_find_gpio() properly

of_get_named_gpiod_flags() used directly in of_find_gpio() or indirectly
through of_find_spi_gpio() or of_find_regulator_gpio() can return
-EPROBE_DEFER. This gets overwritten by the subsequent of_find_*_gpio()
calls.

This patch fixes this by trying of_find_spi_gpio() or
of_find_regulator_gpio() only if deferred probing was not requested by
the previous of_get_named_gpiod_flags() call.

Fixes: 6a537d48461d ("gpio: of: Support regulator nonstandard GPIO properties")
Fixes: c85823390215 ("gpio: of: Support SPI nonstandard GPIO properties")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
[Augmented to fit with Maxime's patch]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index 0ee5dc70268a5a1c5ba5de02f6a31619033ee928..84e5a9df234433b430fc950a04d80dc9cd43bad8 100644 (file)
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -263,7 +263,7 @@ struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
                desc = of_find_spi_gpio(dev, con_id, &of_flags);
 
        /* Special handling for regulator GPIOs if used */
-       if (IS_ERR(desc))
+       if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
                desc = of_find_regulator_gpio(dev, con_id, &of_flags);
 
        if (IS_ERR(desc))