summaryrefslogtreecommitdiffstats
path: root/drivers/gpio
diff options
context:
space:
mode:
authorLinus Walleij <linus.walleij@linaro.org>2018-09-03 09:52:10 +0200
committerLinus Walleij <linus.walleij@linaro.org>2018-09-10 08:48:51 +0200
commitab8c1e82935b8cd034d18c5d0cf944a532a83aea (patch)
treeb0f936c0b05058c3521dedd8fe6c74784e42c9fe /drivers/gpio
parentgpio: twl4030: Cut down boilerplate (diff)
downloadlinux-ab8c1e82935b8cd034d18c5d0cf944a532a83aea.tar.xz
linux-ab8c1e82935b8cd034d18c5d0cf944a532a83aea.zip
gpio: twl4030: Implement .get_direction()
It's nice to be able to read back the direction of the GPIO line from the hardware so implement .get_direction() for twl4030. Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio')
-rw-r--r--drivers/gpio/gpio-twl4030.c42
1 files changed, 41 insertions, 1 deletions
diff --git a/drivers/gpio/gpio-twl4030.c b/drivers/gpio/gpio-twl4030.c
index 1e47ddff33f6..fbfb648d3502 100644
--- a/drivers/gpio/gpio-twl4030.c
+++ b/drivers/gpio/gpio-twl4030.c
@@ -154,6 +154,23 @@ static int twl4030_set_gpio_direction(int gpio, int is_input)
return ret;
}
+static int twl4030_get_gpio_direction(int gpio)
+{
+ u8 d_bnk = gpio >> 3;
+ u8 d_msk = BIT(gpio & 0x7);
+ u8 base = REG_GPIODATADIR1 + d_bnk;
+ int ret = 0;
+
+ ret = gpio_twl4030_read(base);
+ if (ret < 0)
+ return ret;
+
+ /* 1 = output, but gpiolib semantics are inverse so invert */
+ ret = !(ret & d_msk);
+
+ return ret;
+}
+
static int twl4030_set_gpio_dataout(int gpio, int enable)
{
u8 d_bnk = gpio >> 3;
@@ -359,6 +376,28 @@ static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value)
return ret;
}
+static int twl_get_direction(struct gpio_chip *chip, unsigned offset)
+{
+ struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
+ /*
+ * Default 0 = output
+ * LED GPIOs >= TWL4030_GPIO_MAX are always output
+ */
+ int ret = 0;
+
+ mutex_lock(&priv->mutex);
+ if (offset < TWL4030_GPIO_MAX) {
+ ret = twl4030_get_gpio_direction(offset);
+ if (ret) {
+ mutex_unlock(&priv->mutex);
+ return ret;
+ }
+ }
+ mutex_unlock(&priv->mutex);
+
+ return ret;
+}
+
static int twl_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
@@ -374,8 +413,9 @@ static const struct gpio_chip template_chip = {
.request = twl_request,
.free = twl_free,
.direction_input = twl_direction_in,
- .get = twl_get,
.direction_output = twl_direction_out,
+ .get_direction = twl_get_direction,
+ .get = twl_get,
.set = twl_set,
.to_irq = twl_to_irq,
.can_sleep = true,