Sometimes consumers needs to know the gpio-chip local gpio number of a
'struct gpio_desc' for further configuration. This is often the case for
mfd devices.
Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
---
drivers/gpio/gpiolib.c | 6 ++++++
include/linux/gpio/consumer.h | 10 ++++++++++
2 files changed, 16 insertions(+)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 104ed299d5ea..7709648313fc 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -4377,6 +4377,12 @@ int gpiod_count(struct device *dev, const char *con_id)
}
EXPORT_SYMBOL_GPL(gpiod_count);
+int gpiod_to_offset(struct gpio_desc *desc)
+{
+ return gpio_chip_hwgpio(desc);
+}
+EXPORT_SYMBOL_GPL(gpiod_to_offset);
+
/**
* gpiod_get - obtain a GPIO for a given GPIO function
* @dev: GPIO consumer, can be NULL for system-global GPIOs
diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h
index b70af921c614..e2178c3bf7fd 100644
--- a/include/linux/gpio/consumer.h
+++ b/include/linux/gpio/consumer.h
@@ -60,6 +60,9 @@ enum gpiod_flags {
/* Return the number of GPIOs associated with a device / function */
int gpiod_count(struct device *dev, const char *con_id);
+/* Get the local chip offset from a global desc */
+int gpiod_to_offset(struct gpio_desc *desc);
+
/* Acquire and dispose GPIOs */
struct gpio_desc *__must_check gpiod_get(struct device *dev,
const char *con_id,
@@ -189,6 +192,13 @@ static inline int gpiod_count(struct device *dev, const char *con_id)
return 0;
}
+static inline int gpiod_to_offset(struct gpio_desc *desc)
+{
+ /* GPIO can never have been requested */
+ WARN_ON(desc);
+ return 0;
+}
+
static inline struct gpio_desc *__must_check gpiod_get(struct device *dev,
const char *con_id,
enum gpiod_flags flags)
--
2.20.1
