diff mbox

[1/2] gpio: wm831x: use the new open drain callback

Message ID 1460446180-16397-1-git-send-email-linus.walleij@linaro.org
State Accepted
Commit 51c27da19d3dbf3219afb225e1626e193c5e1c72
Headers show

Commit Message

Linus Walleij April 12, 2016, 7:29 a.m. UTC 
The WM831x GPIOs clearly have a dedicated open drain control
register. Implement support for controlling this from GPIO
descriptor tables or other hardware descriptions such as
device tree by implementing the .set_single_ended() callback.

Before this patch, lines requesting open drain will just be
switched to input mode by the framework, thus emulating open
drain. But the hardware can do the real thing, so let's
support that.

As part of this, rename the debugfs string for output mode
from "CMOS" to "push-pull" because it is the term used in
the framework to signify a tomem-pole CMOS output.

Cc: patches@opensource.wolfsonmicro.com
Cc: Mark Brown <broonie@kernel.org>
Cc: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

---
ChangeLog v1->v2:
- Use a switch() statement rather than if-constructions
---
 drivers/gpio/gpio-wm831x.c | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

-- 
2.4.3

--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/drivers/gpio/gpio-wm831x.c b/drivers/gpio/gpio-wm831x.c
index 18cb0f534b91..41ec7834059a 100644
--- a/drivers/gpio/gpio-wm831x.c
+++ b/drivers/gpio/gpio-wm831x.c
@@ -132,6 +132,28 @@  static int wm831x_gpio_set_debounce(struct gpio_chip *chip, unsigned offset,
 	return wm831x_set_bits(wm831x, reg, WM831X_GPN_FN_MASK, fn);
 }
 
+static int wm831x_set_single_ended(struct gpio_chip *chip,
+				   unsigned int offset,
+				   enum single_ended_mode mode)
+{
+	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
+	struct wm831x *wm831x = wm831x_gpio->wm831x;
+	int reg = WM831X_GPIO1_CONTROL + offset;
+
+	switch (mode) {
+	case LINE_MODE_OPEN_DRAIN:
+		return wm831x_set_bits(wm831x, reg,
+				       WM831X_GPN_OD_MASK, WM831X_GPN_OD);
+	case LINE_MODE_PUSH_PULL:
+		return wm831x_set_bits(wm831x, reg,
+				       WM831X_GPN_OD_MASK, 0);
+	default:
+		break;
+	}
+
+	return -ENOTSUPP;
+}
+
 #ifdef CONFIG_DEBUG_FS
 static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 {
@@ -216,7 +238,7 @@  static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 			   pull,
 			   powerdomain,
 			   reg & WM831X_GPN_POL ? "" : " inverted",
-			   reg & WM831X_GPN_OD ? "open-drain" : "CMOS",
+			   reg & WM831X_GPN_OD ? "open-drain" : "push-pull",
 			   tristated ? " tristated" : "",
 			   reg);
 	}
@@ -234,6 +256,7 @@  static struct gpio_chip template_chip = {
 	.set			= wm831x_gpio_set,
 	.to_irq			= wm831x_gpio_to_irq,
 	.set_debounce		= wm831x_gpio_set_debounce,
+	.set_single_ended	= wm831x_set_single_ended,
 	.dbg_show		= wm831x_gpio_dbg_show,
 	.can_sleep		= true,
 };