Commit 99d18d42 authored by Dmitry Torokhov's avatar Dmitry Torokhov Committed by Bartosz Golaszewski
Browse files

gpiolib: of: add a quirk for reset line polarity for Himax LCDs 



Existing DTS that use legacy (non-standard) property name for the reset
line "gpios-reset" also specify incorrect polarity (0 which maps to
"active high"). Add a quirk to force polarity to "active low" so that
once driver is converted to gpiod API that pays attention to line
polarity it will work properly.

Reviewed-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: default avatarDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@linaro.org>
parent b02c85c9

drivers/gpio/gpiolib-of.c

+36 −0
Original line number Diff line number Diff line
@@ -152,11 +152,47 @@ static void of_gpio_quirk_polarity(const struct device_node *np, 
	}

}



/*

 * This quirk does static polarity overrides in cases where existing

 * DTS specified incorrect polarity.

 */

static void of_gpio_try_fixup_polarity(const struct device_node *np,

				       const char *propname,

				       enum of_gpio_flags *flags)

{

	static const struct {

		const char *compatible;

		const char *propname;

		bool active_high;

	} gpios[] = {

#if !IS_ENABLED(CONFIG_LCD_HX8357)

		/*

		 * Himax LCD controllers used incorrectly named

		 * "gpios-reset" property and also specified wrong

		 * polarity.

		 */

		{ "himax,hx8357",	"gpios-reset",	false },

		{ "himax,hx8369",	"gpios-reset",	false },

#endif

	};

	unsigned int i;



	for (i = 0; i < ARRAY_SIZE(gpios); i++) {

		if (of_device_is_compatible(np, gpios[i].compatible) &&

		    !strcmp(propname, gpios[i].propname)) {

			of_gpio_quirk_polarity(np, gpios[i].active_high, flags);

			break;

		}

	}

}



static void of_gpio_flags_quirks(const struct device_node *np,

				 const char *propname,

				 enum of_gpio_flags *flags,

				 int index)

{

	of_gpio_try_fixup_polarity(np, propname, flags);



	/*

	 * Some GPIO fixed regulator quirks.

	 * Note that active low is the default.