[1/4] gpio: add gpiod_toggle_active_low()
diff mbox series

Message ID 56d2568cd45a13c738e2804d04348566a8ee8d03.1575925023.git.mirq-linux@rere.qmqm.pl
State New
Headers show
Series
  • mmc: simplify WP/CD GPIO handling
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Commit Message

Michał Mirosław Dec. 9, 2019, 9:09 p.m. UTC
Add possibility to toggle active-low flag of a gpio descriptor. This is
useful for compatibility code, where defaults are inverted vs DT gpio
flags or the active-low flag is taken from elsewhere.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
---
 drivers/gpio/gpiolib.c        | 11 +++++++++++
 include/linux/gpio/consumer.h |  7 +++++++
 2 files changed, 18 insertions(+)

Comments

Linus Walleij Dec. 11, 2019, 12:39 a.m. UTC | #1
On Mon, Dec 9, 2019 at 10:09 PM Michał Mirosław <mirq-linux@rere.qmqm.pl> wrote:

> Add possibility to toggle active-low flag of a gpio descriptor. This is
> useful for compatibility code, where defaults are inverted vs DT gpio
> flags or the active-low flag is taken from elsewhere.
>
> Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>

Acked-by: Linus Walleij <linus.walleij@linaro.org>

Proliferating APIs isn't good but I think this is the lesser evil
given the mess there is in the MMC subsystem for this stuff.

Maybe I can make a second attempt to move all polarity
toggling back to gpiolib-of.c and remove the API after this
has landed, hehe ;)

Yours,
Linus Walleij

Patch
diff mbox series

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 9913886ede90..6130691e2047 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -3363,6 +3363,17 @@  int gpiod_is_active_low(const struct gpio_desc *desc)
 }
 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
 
+/**
+ * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
+ * @desc: the gpio descriptor to change
+ */
+void gpiod_toggle_active_low(struct gpio_desc *desc)
+{
+	VALIDATE_DESC_VOID(desc);
+	change_bit(FLAG_ACTIVE_LOW, &desc->flags);
+}
+EXPORT_SYMBOL_GPL(gpiod_toggle_active_low);
+
 /* I/O calls are only valid after configuration completed; the relevant
  * "is this a valid GPIO" error checks should already have been done.
  *
diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h
index 5215fdba6b9a..bf2d017dd7b7 100644
--- a/include/linux/gpio/consumer.h
+++ b/include/linux/gpio/consumer.h
@@ -158,6 +158,7 @@  int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
 
 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce);
 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory);
+void gpiod_toggle_active_low(struct gpio_desc *desc);
 
 int gpiod_is_active_low(const struct gpio_desc *desc);
 int gpiod_cansleep(const struct gpio_desc *desc);
@@ -483,6 +484,12 @@  static inline int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
 	return -ENOSYS;
 }
 
+static inline void gpiod_toggle_active_low(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 */