[RESEND PATCH 1/2] extcon: gpio: Add dt support for the driver

George Cherian
2014-11-05T15:32:52Z

Add device tree support to extcon-gpio driver.
Add devicetree binding documentation

While at that
- Cleanup the pdata as there are no users for the same.
- Convert the driver to use gpiod_* API's.
- Some gpio's can sleep while reading, so always use gpio_get_value_cansleep
to get data. This fixes warning from gpiolib due to wrong API usage.

Signed-off-by: George Cherian <george.cherian@ti.com>
---
.../devicetree/bindings/extcon/extcon-gpio.txt | 21 ++++++
drivers/extcon/extcon-gpio.c | 83 +++++++---------------
include/linux/extcon/extcon-gpio.h | 59 ---------------
3 files changed, 46 insertions(+), 117 deletions(-)
create mode 100644 Documentation/devicetree/bindings/extcon/extcon-gpio.txt
delete mode 100644 include/linux/extcon/extcon-gpio.h

diff --git a/Documentation/devicetree/bindings/extcon/extcon-gpio.txt b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt
new file mode 100644
index 0000000..30aa2e1
--- /dev/null
+++ b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt
@@ -0,0 +1,21 @@
+GPIO based EXTCON
+
+EXTCON GPIO
+-----------
+
+Required Properties:
+ - compatible: should be:
+ * "linux,extcon-gpio"
+ - gpios: specifies the gpio pin used.
+
+Optional Properties:
+ - debounce: Debounce time for GPIO IRQ in ms
+
+
+Eg:
+
+ extcon1: am43_usbid_extcon1 {
+ compatible = "linux,extcon-gpio";
+ gpios = <&gpio3 12 GPIO_ACTIVE_HIGH>;
+ debounce = <20>;
+ };
diff --git a/drivers/extcon/extcon-gpio.c b/drivers/extcon/extcon-gpio.c
index 72f19a3..85795de 100644
--- a/drivers/extcon/extcon-gpio.c
+++ b/drivers/extcon/extcon-gpio.c
@@ -21,26 +21,23 @@
*/

#include <linux/extcon.h>
-#include <linux/extcon/extcon-gpio.h>
#include <linux/gpio.h>
#include <linux/init.h>
#include <linux/interrupt.h>
+#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/workqueue.h>

struct gpio_extcon_data {
struct extcon_dev *edev;
- unsigned gpio;
- bool gpio_active_low;
- const char *state_on;
- const char *state_off;
+ struct gpio_desc *gpiod;
int irq;
struct delayed_work work;
unsigned long debounce_jiffies;
- bool check_on_resume;
};

static void gpio_extcon_work(struct work_struct *work)
@@ -50,9 +47,7 @@ static void gpio_extcon_work(struct work_struct *work)
container_of(to_delayed_work(work), struct gpio_extcon_data,
work);

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

@@ -65,34 +60,16 @@ static irqreturn_t gpio_irq_handler(int irq, void *dev_id)
return IRQ_HANDLED;
}

-static ssize_t extcon_gpio_print_state(struct extcon_dev *edev, char *buf)
-{
- struct device *dev = edev->dev.parent;
- struct gpio_extcon_data *extcon_data = dev_get_drvdata(dev);
- const char *state;
-
- if (extcon_get_state(edev))
- state = extcon_data->state_on;
- else
- state = extcon_data->state_off;
-
- if (state)
- return sprintf(buf, "%s\n", state);
- return -EINVAL;
-}
-
static int gpio_extcon_probe(struct platform_device *pdev)
{
- struct gpio_extcon_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ struct device_node *np = pdev->dev.of_node;
struct gpio_extcon_data *extcon_data;
+ unsigned int irq_flags;
+ unsigned int debounce = 0;
int ret;

- if (!pdata)
- return -EBUSY;
- if (!pdata->irq_flags) {
- dev_err(&pdev->dev, "IRQ flag is not specified.\n");
+ if (!np)
return -EINVAL;
- }

extcon_data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_extcon_data),
GFP_KERNEL);
@@ -104,27 +81,23 @@ static int gpio_extcon_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "failed to allocate extcon device\n");
return -ENOMEM;
}
- 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;
- extcon_data->check_on_resume = pdata->check_on_resume;
- if (pdata->state_on && pdata->state_off)
- extcon_data->edev->print_state = extcon_gpio_print_state;
-
- ret = devm_gpio_request_one(&pdev->dev, extcon_data->gpio, GPIOF_DIR_IN,
- pdev->name);
- if (ret < 0)
- return ret;
+ extcon_data->edev->name = np->name;
+ extcon_data->gpiod = gpiod_get(&pdev->dev, NULL);
+ if (IS_ERR(extcon_data->gpiod))
+ return PTR_ERR(extcon_data->gpiod);

- if (pdata->debounce) {
- ret = gpio_set_debounce(extcon_data->gpio,
- pdata->debounce * 1000);
+ extcon_data->irq = gpiod_to_irq(extcon_data->gpiod);
+ if (extcon_data->irq < 0)
+ return extcon_data->irq;
+
+ irq_flags = irq_get_trigger_type(extcon_data->irq);
+ of_property_read_u32(np, "debounce", &debounce);
+ if (debounce) {
+ ret = gpiod_set_debounce(extcon_data->gpiod,
+ debounce * 1000);
if (ret < 0)
extcon_data->debounce_jiffies =
- msecs_to_jiffies(pdata->debounce);
+ msecs_to_jiffies(debounce);
}

ret = devm_extcon_dev_register(&pdev->dev, extcon_data->edev);
@@ -132,13 +105,8 @@ static int gpio_extcon_probe(struct platform_device *pdev)
return ret;

INIT_DELAYED_WORK(&extcon_data->work, gpio_extcon_work);
-
- extcon_data->irq = gpio_to_irq(extcon_data->gpio);
- if (extcon_data->irq < 0)
- return extcon_data->irq;
-
ret = request_any_context_irq(extcon_data->irq, gpio_irq_handler,
- pdata->irq_flags, pdev->name,
+ irq_flags, pdev->name,
extcon_data);
if (ret < 0)
return ret;
@@ -166,9 +134,8 @@ static int gpio_extcon_resume(struct device *dev)
struct gpio_extcon_data *extcon_data;

extcon_data = dev_get_drvdata(dev);
- if (extcon_data->check_on_resume)
- queue_delayed_work(system_power_efficient_wq,
- &extcon_data->work, extcon_data->debounce_jiffies);
+ queue_delayed_work(system_power_efficient_wq,
+ &extcon_data->work, extcon_data->debounce_jiffies);

return 0;
}
diff --git a/include/linux/extcon/extcon-gpio.h b/include/linux/extcon/extcon-gpio.h
deleted file mode 100644
index 0b17ad4..0000000
--- a/include/linux/extcon/extcon-gpio.h
+++ /dev/null
@@ -1,59 +0,0 @@
-/*
- * External connector (extcon) class generic GPIO driver
- *
- * Copyright (C) 2012 Samsung Electronics
- * Author: MyungJoo Ham <myungjoo.ham@samsung.com>
- *
- * based on switch class driver
- * Copyright (C) 2008 Google, Inc.
- * Author: Mike Lockwood <lockwood@android.com>
- *
- * This software is licensed under the terms of the GNU General Public
- * License version 2, as published by the Free Software Foundation, and
- * may be copied, distributed, and modified under those terms.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
-*/
-#ifndef __EXTCON_GPIO_H__
-#define __EXTCON_GPIO_H__ __FILE__
-
-#include <linux/extcon.h>
-
-/**
- * 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, default method of extcon class is used.
- * @state_off: print_state is overriden with state_off if detached.
- * If NUll, default method of extcon class is used.
- * @check_on_resume: Boolean describing whether to check the state of gpio
- * while resuming from sleep.
- *
- * Note that in order for state_on or state_off to be valid, both state_on
- * and state_off should be not NULL. If at least one of them is NULL,
- * the print_state is not overriden.
- */
-struct gpio_extcon_platform_data {
- const char *name;
- unsigned gpio;
- bool gpio_active_low;
- unsigned long debounce;
- unsigned long irq_flags;
-
- /* if NULL, "0" or "1" will be printed */
- const char *state_on;
- const char *state_off;
- bool check_on_resume;
-};
-
-#endif /* __EXTCON_GPIO_H__ */
--
1.8.3.1