From 78c1f6de3c65504645170eaf244d705c9ada88c3 Mon Sep 17 00:00:00 2001 From: Oleksij Rempel Date: Tue, 16 Jul 2019 12:35:55 +0200 Subject: OF: gpio: Add special quirk to parse regulator flags To make fec work with devicetree on imx28-evk, partially port following kernel patch: |commit a603a2b8d86ee93ee2107da8ca75fd854fd4ff32 |Author: Linus Walleij |Date: Sat Dec 30 16:26:36 2017 +0100 | | gpio: of: Add special quirk to parse regulator flags | | While most GPIOs are indicated to be active low or open drain using | their twocell flags, we have legacy regulator bindings to take into | account. | | Add a quirk respecting the special boolean active-high and open | drain flags when parsing regulator nodes for GPIOs. | | This makes it possible to get rid of duplicated inversion semantics | handling in the regulator core and any regulator drivers parsing | and handling this separately. | | Unfortunately the old regulator inversion semantics are specified | such that the presence or absence of "enable-active-high" solely | controls the semantics, so we cannot deprecate this in favor | of the phandle-provided inversion flag, instead any such phandle | inversion flag provided in the second cell of a GPIO handle must be | actively ignored, so we print a warning to contain the situation | and make things easy for the users. | | Signed-off-by: Linus Walleij Signed-off-by: Oleksij Rempel Signed-off-by: Sascha Hauer --- drivers/of/of_gpio.c | 35 ++++++++++++++++++++++++++++++++++- 1 file changed, 34 insertions(+), 1 deletion(-) (limited to 'drivers/of/of_gpio.c') diff --git a/drivers/of/of_gpio.c b/drivers/of/of_gpio.c index dc8ae22776..9a8331ed18 100644 --- a/drivers/of/of_gpio.c +++ b/drivers/of/of_gpio.c @@ -4,6 +4,37 @@ #include #include +static void of_gpio_flags_quirks(struct device_node *np, + const char *propname, + enum of_gpio_flags *flags, + int index) +{ + /* + * Some GPIO fixed regulator quirks. + * Note that active low is the default. + */ + if (IS_ENABLED(CONFIG_REGULATOR) && + (of_device_is_compatible(np, "regulator-fixed") || + of_device_is_compatible(np, "reg-fixed-voltage") || + (!(strcmp(propname, "enable-gpio") && + strcmp(propname, "enable-gpios")) && + of_device_is_compatible(np, "regulator-gpio")))) { + /* + * The regulator GPIO handles are specified such that the + * presence or absence of "enable-active-high" solely controls + * the polarity of the GPIO line. Any phandle flags must + * be actively ignored. + */ + if (*flags & OF_GPIO_ACTIVE_LOW) { + pr_warn("%s GPIO handle specifies active low - ignored\n", + np->full_name); + *flags &= ~OF_GPIO_ACTIVE_LOW; + } + if (!of_property_read_bool(np, "enable-active-high")) + *flags |= OF_GPIO_ACTIVE_LOW; + } +} + /** * of_get_named_gpio_flags() - Get a GPIO number and flags to use with GPIO API * @np: device node to get GPIO from @@ -46,8 +77,10 @@ int of_get_named_gpio_flags(struct device_node *np, const char *propname, return ret; } - if (flags) + if (flags) { *flags = out_args.args[1]; + of_gpio_flags_quirks(np, propname, flags, index); + } return ret; } -- cgit v1.2.3