[U-Boot] [PATCH v3 3/3] dm: gpio: Implement open drain for MPC85XX GPIO

[Mario Six]

From: "mario.six at gdsys.cc" <mario.six at gdsys.cc>

This patch implements the open-drain setting feature for the MPC85XX
GPIO controller.

Signed-off-by: Mario Six <mario.six at gdsys.cc>
---

v3:
- Added comments

v2:
- Added missing commit message
- Fixed white space issues in function headers

---
 drivers/gpio/Kconfig        |  6 +++---
 drivers/gpio/mpc85xx_gpio.c | 19 +++++++++++++++++++
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 068ee63..b250622 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -162,9 +162,9 @@ config MPC85XX_GPIO
 	  configurable to match the actual GPIO count of the SoC (e.g. the
 	  32/32/23 banks of the P1022 SoC).

-	  The standard functions of input/output mode, and output value setting
-	  are supported; the open-drain capability of the controller is not
-	  supported yet.
+	  Aside from the standard functions of input/output mode, and output
+	  value setting, the open-drain feature, which can configure individual
+	  GPIOs to work as open-drain outputs, is supported.

 	  The driver has been tested on MPC85XX, but it is likely that other
 	  PowerQUICC III devices will work as well.
diff --git a/drivers/gpio/mpc85xx_gpio.c b/drivers/gpio/mpc85xx_gpio.c
index 17755df..1c1f6f3 100644
--- a/drivers/gpio/mpc85xx_gpio.c
+++ b/drivers/gpio/mpc85xx_gpio.c
@@ -73,6 +73,25 @@ static inline void mpc85xx_gpio_set_high(struct ccsr_gpio *base, u32 gpios)
 	setbits_be32(&base->gpdir, gpios);
 }

+static inline int mpc85xx_gpio_open_drain_val(struct ccsr_gpio *base, u32 mask)
+{
+	return in_be32(&base->gpodr) & mask;
+}
+
+static inline void mpc85xx_gpio_open_drain_on(struct ccsr_gpio *base, u32
+					      gpios)
+{
+	/* GPODR register 1 -> open drain on */
+	setbits_be32(&base->gpodr, gpios);
+}
+
+static inline void mpc85xx_gpio_open_drain_off(struct ccsr_gpio *base,
+					       u32 gpios)
+{
+	/* GPODR register 0 -> open drain off (actively driven) */
+	clrbits_be32(&base->gpodr, gpios);
+}
+
 static int mpc85xx_gpio_direction_input(struct udevice *dev, unsigned gpio)
 {
 	struct mpc85xx_gpio_data *data = dev_get_priv(dev);
--
2.7.0.GIT