[PATCH 1/5] gpiolib: provide gpiod_set_active_[low/high]()

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bartosz.golaszewski at linaro.org>

Out current interface for changing line polarity is quite cumbersome to
use as it only "toggles" the current state instead of deterministically
setting it. Because of that all but one user in the kernel first need
check the current state anyway. Let's provide two new functions that
allow users to set this value explicitly with the aim of removing the
existing function.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski at linaro.org>
---
 drivers/gpio/gpiolib.c        | 22 ++++++++++++++++++++++
 include/linux/gpio/consumer.h | 14 ++++++++++++++
 2 files changed, 36 insertions(+)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index edffa0d2acaa..131965814a7c 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -2725,6 +2725,28 @@ void gpiod_toggle_active_low(struct gpio_desc *desc)
 }
 EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
 
+/**
+ * gpiod_set_active_low() - set the GPIO as active-low
+ * @desc: the GPIO descriptor to set the active-low setting for
+ */
+void gpiod_set_active_low(struct gpio_desc *desc)
+{
+	VALIDATE_DESC_VOID(desc);
+	set_bit(FLAG_ACTIVE_LOW, &desc->flags);
+}
+EXPORT_SYMBOL_GPL(gpiod_set_active_low);
+
+/**
+ * gpiod_set_active_high() - set the GPIO as active-high
+ * @desc: the GPIO descriptor to set the active-low setting for
+ */
+void gpiod_set_active_high(struct gpio_desc *desc)
+{
+	VALIDATE_DESC_VOID(desc);
+	clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
+}
+EXPORT_SYMBOL_GPL(gpiod_set_active_high);
+
 static int gpio_chip_get_value(struct gpio_chip *gc, const struct gpio_desc *desc)
 {
 	return gc->get ? gc->get(gc, gpio_chip_hwgpio(desc)) : -EIO;
diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h
index 6cc345440a5b..ddbf0d8e4a75 100644
--- a/include/linux/gpio/consumer.h
+++ b/include/linux/gpio/consumer.h
@@ -160,6 +160,8 @@ int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
 int gpiod_set_config(struct gpio_desc *desc, unsigned long config);
 int gpiod_set_debounce(struct gpio_desc *desc, unsigned int debounce);
 void gpiod_toggle_active_low(struct gpio_desc *desc);
+void gpiod_set_active_low(struct gpio_desc *desc);
+void gpiod_set_active_high(struct gpio_desc *desc);
 
 int gpiod_is_active_low(const struct gpio_desc *desc);
 int gpiod_cansleep(const struct gpio_desc *desc);
@@ -499,6 +501,18 @@ static inline void gpiod_toggle_active_low(struct gpio_desc *desc)
 	WARN_ON(desc);
 }
 
+static inline void gpiod_set_active_low(struct gpio_desc *desc
+{
+	/* GPIO can never have been requested */
+	WARN_ON(desc);
+}
+
+static inline void gpiod_set_active_high(struct gpio_desc *desc)
+{
+	/* GPIO can never have been requested */
+	WARN_ON(desc);
+}
+
 static inline int gpiod_is_active_low(const struct gpio_desc *desc)
 {
 	/* GPIO can never have been requested */
-- 
2.39.2