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authorEric Miao <eric.y.miao@gmail.com>2010-03-05 13:44:35 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2010-03-06 11:26:48 -0800
commit3e45f1d1155894e6f4291f5536b224874d52d8e2 (patch)
treed7b44dd5248bdb053c0cd6632e82ce8893833519 /drivers/gpio
parent62fecb70cfaa9b4c6aa1981acd53b18f4ad925f0 (diff)
gpio: introduce gpio_request_one() and friends
gpio_request() without initial configuration of the GPIO is normally useless, introduce gpio_request_one() together with GPIOF_ flags for input/output direction and initial output level. gpio_{request,free}_array() for multiple GPIOs. Signed-off-by: Eric Miao <eric.y.miao@gmail.com> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Ben Nizette <bn@niasdigital.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/gpio')
-rw-r--r--drivers/gpio/gpiolib.c58
1 files changed, 58 insertions, 0 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 350842ad3632..9006fdb26fea 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1237,6 +1237,64 @@ void gpio_free(unsigned gpio)
}
EXPORT_SYMBOL_GPL(gpio_free);
+/**
+ * gpio_request_one - request a single GPIO with initial configuration
+ * @gpio: the GPIO number
+ * @flags: GPIO configuration as specified by GPIOF_*
+ * @label: a literal description string of this GPIO
+ */
+int gpio_request_one(unsigned gpio, unsigned long flags, const char *label)
+{
+ int err;
+
+ err = gpio_request(gpio, label);
+ if (err)
+ return err;
+
+ if (flags & GPIOF_DIR_IN)
+ err = gpio_direction_input(gpio);
+ else
+ err = gpio_direction_output(gpio,
+ (flags & GPIOF_INIT_HIGH) ? 1 : 0);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(gpio_request_one);
+
+/**
+ * gpio_request_array - request multiple GPIOs in a single call
+ * @array: array of the 'struct gpio'
+ * @num: how many GPIOs in the array
+ */
+int gpio_request_array(struct gpio *array, size_t num)
+{
+ int i, err;
+
+ for (i = 0; i < num; i++, array++) {
+ err = gpio_request_one(array->gpio, array->flags, array->label);
+ if (err)
+ goto err_free;
+ }
+ return 0;
+
+err_free:
+ while (i--)
+ gpio_free((--array)->gpio);
+ return err;
+}
+EXPORT_SYMBOL_GPL(gpio_request_array);
+
+/**
+ * gpio_free_array - release multiple GPIOs in a single call
+ * @array: array of the 'struct gpio'
+ * @num: how many GPIOs in the array
+ */
+void gpio_free_array(struct gpio *array, size_t num)
+{
+ while (num--)
+ gpio_free((array++)->gpio);
+}
+EXPORT_SYMBOL_GPL(gpio_free_array);
/**
* gpiochip_is_requested - return string iff signal was requested