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

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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: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
This commit is contained in:
Dmitry Torokhov 2022-10-17 22:41:11 -07:00 committed by Bartosz Golaszewski
parent b02c85c945
commit 99d18d42c9
1 changed files with 36 additions and 0 deletions
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36
drivers/gpio/gpiolib-of.c
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@ -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.