From 0e7d6f94016407fd7e1ae472e254d64d4454e9c8 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Sat, 16 Feb 2019 14:46:27 +0100 Subject: [PATCH] gpio: of: Apply regulator-gpio quirk only to enable-gpios Since commit d6cd33ad7102 ("regulator: gpio: Convert to use descriptors") the GPIO regulator had inverted the polarity of the control GPIO. This problem manifested itself on systems with DT containing the following description (snippet from salvator-common.dtsi): gpios = <&gpio5 1 GPIO_ACTIVE_HIGH>; gpios-states = <1>; states = <3300000 1 1800000 0>; Prior to the aforementioned commit, the gpio-regulator code used gpio_request_array() to claim the GPIO(s) specified in the "gpios" DT node, while the commit changed that to devm_gpiod_get_index(). The legacy gpio_request_array() calls gpio_request_one() and then gpiod_request(), which parses the DT flags of the "gpios" node and populates the GPIO descriptor flags field accordingly. The new devm_gpiod_get_index() calls gpiod_get_index(), then of_find_gpio(), of_get_named_gpiod_flags() with flags != NULL, and then of_gpio_flags_quirks(). Since commit a603a2b8d86e ("gpio: of: Add special quirk to parse regulator flags"), of_gpio_flags_quirks() contains a quirk for regulator-gpio which was never triggered by the legacy gpio_request_array() code path, but is triggered by devm_gpiod_get_index() code path. This quirk checks whether a GPIO is associated with a fixed or gpio-regulator and if so, checks two additional conditions. First, whether such GPIO is active-low, and if so, ignores the active-low flag. Second, whether the regulator DT node does have an "enable-active-high" property and if the property is NOT present, sets the GPIO flags as active-low. The second check triggers a problem, since it is applied to all GPIOs associated with a gpio-regulator, rather than only on the "enable" GPIOs, as the old code did. This changes the way the gpio-regulator interprets the DT description of the control GPIOs. The old code using gpio_request_array() explicitly parsed the "enable-active-high" DT property and only applied it to the GPIOs described in the "enable-gpios" DT node, and only if those were present. This patch fixes the quirk code by only applying the quirk to "enable-gpios", thus restoring the old behavior. Signed-off-by: Marek Vasut Cc: Geert Uytterhoeven Cc: Jan Kotas Cc: Linus Walleij Cc: Mark Brown Cc: Wolfram Sang Cc: linux-renesas-soc@vger.kernel.org To: linux-gpio@vger.kernel.org Signed-off-by: Linus Walleij --- drivers/gpio/gpiolib-of.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index 9a8b78477f79..4547dba19956 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -84,6 +84,7 @@ static void of_gpio_flags_quirks(struct device_node *np, * Note that active low is the default. */ if (IS_ENABLED(CONFIG_REGULATOR) && + !strcmp(propname, "enable-gpio") && (of_device_is_compatible(np, "regulator-fixed") || of_device_is_compatible(np, "reg-fixed-voltage") || of_device_is_compatible(np, "regulator-gpio"))) {