[PATCH v2 3/6] extcon-gpio: Add support for active-low presencedetect pins

From: Guenter Roeck
Date: Tue Sep 10 2013 - 22:25:25 EST



Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
v2: Document gpio_active_low variable in gpio_extcon_platform_data
Rewrite active-low logic to be easier to read.

drivers/extcon/extcon-gpio.c | 4 ++++
include/linux/extcon/extcon-gpio.h | 5 +++++
2 files changed, 9 insertions(+)

diff --git a/drivers/extcon/extcon-gpio.c b/drivers/extcon/extcon-gpio.c
index 862743b..8491f86 100644
--- a/drivers/extcon/extcon-gpio.c
+++ b/drivers/extcon/extcon-gpio.c
@@ -34,6 +34,7 @@
struct gpio_extcon_data {
struct extcon_dev edev;
unsigned gpio;
+ bool gpio_active_low;
const char *state_on;
const char *state_off;
int irq;
@@ -49,6 +50,8 @@ static void gpio_extcon_work(struct work_struct *work)
work);

state = gpio_get_value(data->gpio);
+ if (data->gpio_active_low)
+ state = !state;
extcon_set_state(&data->edev, state);
}

@@ -96,6 +99,7 @@ static int gpio_extcon_probe(struct platform_device *pdev)

extcon_data->edev.name = pdata->name;
extcon_data->gpio = pdata->gpio;
+ extcon_data->gpio_active_low = pdata->gpio_active_low;
extcon_data->state_on = pdata->state_on;
extcon_data->state_off = pdata->state_off;
if (pdata->state_on && pdata->state_off)
diff --git a/include/linux/extcon/extcon-gpio.h b/include/linux/extcon/extcon-gpio.h
index 2d8307f..51ef15c 100644
--- a/include/linux/extcon/extcon-gpio.h
+++ b/include/linux/extcon/extcon-gpio.h
@@ -27,6 +27,10 @@
* struct gpio_extcon_platform_data - A simple GPIO-controlled extcon device.
* @name The name of this GPIO extcon device.
* @gpio Corresponding GPIO.
+ * @gpio_active_low:
+ * Boolean describing whether gpio active state is 1 or 0
+ * If true, low state of gpio means active.
+ * If false, high state of gpio means active.
* @debounce Debounce time for GPIO IRQ in ms.
* @irq_flags IRQ Flags (e.g., IRQF_TRIGGER_LOW).
* @state_on print_state is overriden with state_on if attached. If Null,
@@ -41,6 +45,7 @@
struct gpio_extcon_platform_data {
const char *name;
unsigned gpio;
+ bool gpio_active_low;
unsigned long debounce;
unsigned long irq_flags;

--
1.7.9.7

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/