Input: add driver for Sharp gp2ap002a00f proximity sensor

This driver adds support for Sharp's GP2AP002A00F proximity sensor. The
proximity is measured as a binary switch, i.e. an object is either
detected or not detected. Hence, this driver is implemented as a switch
that reports SW_FRONT_PROXIMITY.

Reviewed-by: Datta Shubhrajyoti <shubhrajyoti@ti.com>
Signed-off-by: Courtney Cavin <courtney.cavin@sonyericsson.com>
Signed-off-by: Oskar Andero <oskar.andero@sonyericsson.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/misc/gp2ap002a00f.c b/drivers/input/misc/gp2ap002a00f.c
new file mode 100644
index 0000000..71fba8c
--- /dev/null
+++ b/drivers/input/misc/gp2ap002a00f.c
@@ -0,0 +1,299 @@
+/*
+ * Copyright (C) 2011 Sony Ericsson Mobile Communications Inc.
+ *
+ * Author: Courtney Cavin <courtney.cavin@sonyericsson.com>
+ * Prepared for up-stream by: Oskar Andero <oskar.andero@sonyericsson.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/i2c.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/input/gp2ap002a00f.h>
+
+struct gp2a_data {
+	struct input_dev *input;
+	const struct gp2a_platform_data *pdata;
+	struct i2c_client *i2c_client;
+};
+
+enum gp2a_addr {
+	GP2A_ADDR_PROX	= 0x0,
+	GP2A_ADDR_GAIN	= 0x1,
+	GP2A_ADDR_HYS	= 0x2,
+	GP2A_ADDR_CYCLE	= 0x3,
+	GP2A_ADDR_OPMOD	= 0x4,
+	GP2A_ADDR_CON	= 0x6
+};
+
+enum gp2a_controls {
+	/* Software Shutdown control: 0 = shutdown, 1 = normal operation */
+	GP2A_CTRL_SSD	= 0x01
+};
+
+static int gp2a_report(struct gp2a_data *dt)
+{
+	int vo = gpio_get_value(dt->pdata->vout_gpio);
+
+	input_report_switch(dt->input, SW_FRONT_PROXIMITY, !vo);
+	input_sync(dt->input);
+
+	return 0;
+}
+
+static irqreturn_t gp2a_irq(int irq, void *handle)
+{
+	struct gp2a_data *dt = handle;
+
+	gp2a_report(dt);
+
+	return IRQ_HANDLED;
+}
+
+static int gp2a_enable(struct gp2a_data *dt)
+{
+	return i2c_smbus_write_byte_data(dt->i2c_client, GP2A_ADDR_OPMOD,
+					 GP2A_CTRL_SSD);
+}
+
+static int gp2a_disable(struct gp2a_data *dt)
+{
+	return i2c_smbus_write_byte_data(dt->i2c_client, GP2A_ADDR_OPMOD,
+					 0x00);
+}
+
+static int gp2a_device_open(struct input_dev *dev)
+{
+	struct gp2a_data *dt = input_get_drvdata(dev);
+	int error;
+
+	error = gp2a_enable(dt);
+	if (error < 0) {
+		dev_err(&dt->i2c_client->dev,
+			"unable to activate, err %d\n", error);
+		return error;
+	}
+
+	gp2a_report(dt);
+
+	return 0;
+}
+
+static void gp2a_device_close(struct input_dev *dev)
+{
+	struct gp2a_data *dt = input_get_drvdata(dev);
+	int error;
+
+	error = gp2a_disable(dt);
+	if (error < 0)
+		dev_err(&dt->i2c_client->dev,
+			"unable to deactivate, err %d\n", error);
+}
+
+static int __devinit gp2a_initialize(struct gp2a_data *dt)
+{
+	int error;
+
+	error = i2c_smbus_write_byte_data(dt->i2c_client, GP2A_ADDR_GAIN,
+					  0x08);
+	if (error < 0)
+		return error;
+
+	error = i2c_smbus_write_byte_data(dt->i2c_client, GP2A_ADDR_HYS,
+					  0xc2);
+	if (error < 0)
+		return error;
+
+	error = i2c_smbus_write_byte_data(dt->i2c_client, GP2A_ADDR_CYCLE,
+					  0x04);
+	if (error < 0)
+		return error;
+
+	error = gp2a_disable(dt);
+
+	return error;
+}
+
+static int __devinit gp2a_probe(struct i2c_client *client,
+				const struct i2c_device_id *id)
+{
+	const struct gp2a_platform_data *pdata = client->dev.platform_data;
+	struct gp2a_data *dt;
+	int error;
+
+	if (!pdata)
+		return -EINVAL;
+
+	if (pdata->hw_setup) {
+		error = pdata->hw_setup(client);
+		if (error < 0)
+			return error;
+	}
+
+	error = gpio_request_one(pdata->vout_gpio, GPIOF_IN, GP2A_I2C_NAME);
+	if (error)
+		goto err_hw_shutdown;
+
+	dt = kzalloc(sizeof(struct gp2a_data), GFP_KERNEL);
+	if (!dt) {
+		error = -ENOMEM;
+		goto err_free_gpio;
+	}
+
+	dt->pdata = pdata;
+	dt->i2c_client = client;
+
+	error = gp2a_initialize(dt);
+	if (error < 0)
+		goto err_free_mem;
+
+	dt->input = input_allocate_device();
+	if (!dt->input) {
+		error = -ENOMEM;
+		goto err_free_mem;
+	}
+
+	input_set_drvdata(dt->input, dt);
+
+	dt->input->open = gp2a_device_open;
+	dt->input->close = gp2a_device_close;
+	dt->input->name = GP2A_I2C_NAME;
+	dt->input->id.bustype = BUS_I2C;
+	dt->input->dev.parent = &client->dev;
+
+	input_set_capability(dt->input, EV_SW, SW_FRONT_PROXIMITY);
+
+	error = request_threaded_irq(client->irq, NULL, gp2a_irq,
+			IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
+				IRQF_ONESHOT,
+			GP2A_I2C_NAME, dt);
+	if (error) {
+		dev_err(&client->dev, "irq request failed\n");
+		goto err_free_input_dev;
+	}
+
+	error = input_register_device(dt->input);
+	if (error) {
+		dev_err(&client->dev, "device registration failed\n");
+		goto err_free_irq;
+	}
+
+	device_init_wakeup(&client->dev, pdata->wakeup);
+	i2c_set_clientdata(client, dt);
+
+	return 0;
+
+err_free_irq:
+	free_irq(client->irq, dt);
+err_free_input_dev:
+	input_free_device(dt->input);
+err_free_mem:
+	kfree(dt);
+err_free_gpio:
+	gpio_free(pdata->vout_gpio);
+err_hw_shutdown:
+	if (pdata->hw_shutdown)
+		pdata->hw_shutdown(client);
+	return error;
+}
+
+static int __devexit gp2a_remove(struct i2c_client *client)
+{
+	struct gp2a_data *dt = i2c_get_clientdata(client);
+	const struct gp2a_platform_data *pdata = dt->pdata;
+
+	device_init_wakeup(&client->dev, false);
+
+	free_irq(client->irq, dt);
+
+	input_unregister_device(dt->input);
+	kfree(dt);
+
+	gpio_free(pdata->vout_gpio);
+
+	if (pdata->hw_shutdown)
+		pdata->hw_shutdown(client);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int gp2a_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct gp2a_data *dt = i2c_get_clientdata(client);
+	int retval = 0;
+
+	if (device_may_wakeup(&client->dev)) {
+		enable_irq_wake(client->irq);
+	} else {
+		mutex_lock(&dt->input->mutex);
+		if (dt->input->users)
+			retval = gp2a_disable(dt);
+		mutex_unlock(&dt->input->mutex);
+	}
+
+	return retval;
+}
+
+static int gp2a_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct gp2a_data *dt = i2c_get_clientdata(client);
+	int retval = 0;
+
+	if (device_may_wakeup(&client->dev)) {
+		disable_irq_wake(client->irq);
+	} else {
+		mutex_lock(&dt->input->mutex);
+		if (dt->input->users)
+			retval = gp2a_enable(dt);
+		mutex_unlock(&dt->input->mutex);
+	}
+
+	return retval;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(gp2a_pm, gp2a_suspend, gp2a_resume);
+
+static const struct i2c_device_id gp2a_i2c_id[] = {
+	{ GP2A_I2C_NAME, 0 },
+	{ }
+};
+
+static struct i2c_driver gp2a_i2c_driver = {
+	.driver = {
+		.name	= GP2A_I2C_NAME,
+		.owner	= THIS_MODULE,
+		.pm	= &gp2a_pm,
+	},
+	.probe		= gp2a_probe,
+	.remove		= __devexit_p(gp2a_remove),
+	.id_table	= gp2a_i2c_id,
+};
+
+static int __init gp2a_init(void)
+{
+	return i2c_add_driver(&gp2a_i2c_driver);
+}
+
+static void __exit gp2a_exit(void)
+{
+	i2c_del_driver(&gp2a_i2c_driver);
+}
+
+module_init(gp2a_init);
+module_exit(gp2a_exit);
+
+MODULE_AUTHOR("Courtney Cavin <courtney.cavin@sonyericsson.com>");
+MODULE_DESCRIPTION("Sharp GP2AP002A00F I2C Proximity/Opto sensor driver");
+MODULE_LICENSE("GPL v2");