[PATCH] gpio: generic: add get_direction support

From: Philipp Zabel
Date: Fri Jun 12 2015 - 12:20:46 EST


Allow to determine the current direction configuration by
reading back from the direction register.

Signed-off-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
---
drivers/gpio/gpio-generic.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)

diff --git a/drivers/gpio/gpio-generic.c b/drivers/gpio/gpio-generic.c
index b92a690..fb9c572 100644
--- a/drivers/gpio/gpio-generic.c
+++ b/drivers/gpio/gpio-generic.c
@@ -291,6 +291,14 @@ static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
return 0;
}

+static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio)
+{
+ struct bgpio_chip *bgc = to_bgpio_chip(gc);
+
+ return (bgc->read_reg(bgc->reg_dir) & bgc->pin2mask(bgc, gpio)) ?
+ GPIOF_DIR_OUT : GPIOF_DIR_IN;
+}
+
static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
{
struct bgpio_chip *bgc = to_bgpio_chip(gc);
@@ -340,6 +348,14 @@ static int bgpio_dir_out_inv(struct gpio_chip *gc, unsigned int gpio, int val)
return 0;
}

+static int bgpio_get_dir_inv(struct gpio_chip *gc, unsigned int gpio)
+{
+ struct bgpio_chip *bgc = to_bgpio_chip(gc);
+
+ return (bgc->read_reg(bgc->reg_dir) & bgc->pin2mask(bgc, gpio)) ?
+ GPIOF_DIR_IN : GPIOF_DIR_OUT;
+}
+
static int bgpio_setup_accessors(struct device *dev,
struct bgpio_chip *bgc,
bool bit_be,
@@ -452,10 +468,12 @@ static int bgpio_setup_direction(struct bgpio_chip *bgc,
bgc->reg_dir = dirout;
bgc->gc.direction_output = bgpio_dir_out;
bgc->gc.direction_input = bgpio_dir_in;
+ bgc->gc.get_direction = bgpio_get_dir;
} else if (dirin) {
bgc->reg_dir = dirin;
bgc->gc.direction_output = bgpio_dir_out_inv;
bgc->gc.direction_input = bgpio_dir_in_inv;
+ bgc->gc.get_direction = bgpio_get_dir_inv;
} else {
bgc->gc.direction_output = bgpio_simple_dir_out;
bgc->gc.direction_input = bgpio_simple_dir_in;
--
2.1.4

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