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-rw-r--r--drivers/gpio/gpiolib.c43
-rw-r--r--include/asm-generic/gpio.h5
-rw-r--r--include/linux/gpio.h5
3 files changed, 53 insertions, 0 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 362a613d266e..3ca36542e338 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1447,6 +1447,49 @@ fail:
}
EXPORT_SYMBOL_GPL(gpio_direction_output);
+/**
+ * gpio_set_debounce - sets @debounce time for a @gpio
+ * @gpio: the gpio to set debounce time
+ * @debounce: debounce time is microseconds
+ */
+int gpio_set_debounce(unsigned gpio, unsigned debounce)
+{
+ unsigned long flags;
+ struct gpio_chip *chip;
+ struct gpio_desc *desc = &gpio_desc[gpio];
+ int status = -EINVAL;
+
+ spin_lock_irqsave(&gpio_lock, flags);
+
+ if (!gpio_is_valid(gpio))
+ goto fail;
+ chip = desc->chip;
+ if (!chip || !chip->set || !chip->set_debounce)
+ goto fail;
+ gpio -= chip->base;
+ if (gpio >= chip->ngpio)
+ goto fail;
+ status = gpio_ensure_requested(desc, gpio);
+ if (status < 0)
+ goto fail;
+
+ /* now we know the gpio is valid and chip won't vanish */
+
+ spin_unlock_irqrestore(&gpio_lock, flags);
+
+ might_sleep_if(extra_checks && chip->can_sleep);
+
+ return chip->set_debounce(chip, gpio, debounce);
+
+fail:
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ if (status)
+ pr_debug("%s: gpio-%d status %d\n",
+ __func__, gpio, status);
+
+ return status;
+}
+EXPORT_SYMBOL_GPL(gpio_set_debounce);
/* 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/asm-generic/gpio.h b/include/asm-generic/gpio.h
index fb1ecf8baa90..4f3d75e1ad39 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -90,6 +90,9 @@ struct gpio_chip {
unsigned offset);
int (*direction_output)(struct gpio_chip *chip,
unsigned offset, int value);
+ int (*set_debounce)(struct gpio_chip *chip,
+ unsigned offset, unsigned debounce);
+
void (*set)(struct gpio_chip *chip,
unsigned offset, int value);
@@ -123,6 +126,8 @@ extern void gpio_free(unsigned gpio);
extern int gpio_direction_input(unsigned gpio);
extern int gpio_direction_output(unsigned gpio, int value);
+extern int gpio_set_debounce(unsigned gpio, unsigned debounce);
+
extern int gpio_get_value_cansleep(unsigned gpio);
extern void gpio_set_value_cansleep(unsigned gpio, int value);
diff --git a/include/linux/gpio.h b/include/linux/gpio.h
index 4e949a5b5b85..03f616b78cfa 100644
--- a/include/linux/gpio.h
+++ b/include/linux/gpio.h
@@ -51,6 +51,11 @@ static inline int gpio_direction_output(unsigned gpio, int value)
return -ENOSYS;
}
+static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
+{
+ return -ENOSYS;
+}
+
static inline int gpio_get_value(unsigned gpio)
{
/* GPIO can never have been requested or set as {in,out}put */