From 6662ae6af82df10259a70c7569b4c12ea7f3ba93 Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Wed, 21 Feb 2018 09:11:00 +0100 Subject: gpiolib: Keep returning EPROBE_DEFER when we should Commits c85823390215 ("gpio: of: Support SPI nonstandard GPIO properties") and 6a537d48461d ("gpio: of: Support regulator nonstandard GPIO properties") have introduced a regression in the way error codes from of_get_named_gpiod_flags are handled. Previously, those errors codes were returned immediately, but the two commits mentioned above are now overwriting the error pointer, meaning that whatever value has been returned will be dropped in favor of whatever the two new functions will return. This might not be a big deal except for EPROBE_DEFER, on which GPIOlib customers will depend on, and that will now be returned as an hard error which means that they will not probe anymore, instead of gently deferring their probe. Since EPROBE_DEFER basically means that we have found a valid property but there was no GPIO controller registered to handle it, fix this issues by returning it as soon as we encounter it. Fixes: c85823390215 ("gpio: of: Support SPI nonstandard GPIO properties") Fixes: 6a537d48461d ("gpio: of: Support regulator nonstandard GPIO properties") Signed-off-by: Maxime Ripard [Fold in fix to the fix] Signed-off-by: Linus Walleij --- drivers/gpio/gpiolib-of.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index 564bb7a31da4..0ee5dc70268a 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -241,6 +241,19 @@ struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx, &of_flags); + /* + * -EPROBE_DEFER in our case means that we found a + * valid GPIO property, but no controller has been + * registered so far. + * + * This means we don't need to look any further for + * alternate name conventions, and we should really + * preserve the return code for our user to be able to + * retry probing later. + */ + if (IS_ERR(desc) && PTR_ERR(desc) == -EPROBE_DEFER) + return desc; + if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT)) break; } -- cgit v1.2.3 From ce27fb2c56db6ccfe8099343bb4afdab15e77e7b Mon Sep 17 00:00:00 2001 From: Chen-Yu Tsai Date: Tue, 13 Feb 2018 14:08:14 +0800 Subject: 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 [Augmented to fit with Maxime's patch] Signed-off-by: Linus Walleij --- drivers/gpio/gpiolib-of.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index 0ee5dc70268a..84e5a9df2344 100644 --- 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)) -- cgit v1.2.3