Input: add support for OnKey module for DA9052/53 PMIC

On-key Driver for Dialog Semiconductor DA9052/53 PMICs.

Signed-off-by: David Dajun Chen <[e-mail]>
Signed-off-by: Ashish Jangam <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/misc/Kconfig

···
 	  To compile this driver as a module, choose M here: the
 	  module will be called rb532_button.
 
+config INPUT_DA9052_ONKEY
+	tristate "Dialog DA9052/DA9053 Onkey"
+	depends on PMIC_DA9052
+	help
+	  Support the ONKEY of Dialog DA9052 PMICs as an input device
+	  reporting power button status.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called da9052_onkey.
+
 config INPUT_DM355EVM
 	tristate "TI DaVinci DM355 EVM Keypad and IR Remote"
 	depends on MFD_DM355EVM_MSP

drivers/input/misc/Makefile

···
 obj-$(CONFIG_INPUT_CMA3000)		+= cma3000_d0x.o
 obj-$(CONFIG_INPUT_CMA3000_I2C)		+= cma3000_d0x_i2c.o
 obj-$(CONFIG_INPUT_COBALT_BTNS)		+= cobalt_btns.o
+obj-$(CONFIG_INPUT_DA9052_ONKEY)	+= da9052_onkey.o
 obj-$(CONFIG_INPUT_DM355EVM)		+= dm355evm_keys.o
 obj-$(CONFIG_INPUT_GP2A)		+= gp2ap002a00f.o
 obj-$(CONFIG_INPUT_GPIO_TILT_POLLED)	+= gpio_tilt_polled.o

drivers/input/misc/da9052_onkey.c

···
+/*
+ * ON pin driver for Dialog DA9052 PMICs
+ *
+ * Copyright(c) 2012 Dialog Semiconductor Ltd.
+ *
+ * Author: David Dajun Chen <[e-mail]>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/workqueue.h>
+
+#include <linux/mfd/da9052/da9052.h>
+#include <linux/mfd/da9052/reg.h>
+
+struct da9052_onkey {
+	struct da9052 *da9052;
+	struct input_dev *input;
+	struct delayed_work work;
+	unsigned int irq;
+};
+
+static void da9052_onkey_query(struct da9052_onkey *onkey)
+{
+	int key_stat;
+
+	key_stat = da9052_reg_read(onkey->da9052, DA9052_EVENT_B_REG);
+	if (key_stat < 0) {
+		dev_err(onkey->da9052->dev,
+			"Failed to read onkey event %d\n", key_stat);
+	} else {
+		/*
+		 * Since interrupt for deassertion of ONKEY pin is not
+		 * generated, onkey event state determines the onkey
+		 * button state.
+		 */
+		key_stat &= DA9052_EVENTB_ENONKEY;
+		input_report_key(onkey->input, KEY_POWER, key_stat);
+		input_sync(onkey->input);
+	}
+
+	/*
+	 * Interrupt is generated only when the ONKEY pin is asserted.
+	 * Hence the deassertion of the pin is simulated through work queue.
+	 */
+	if (key_stat)
+		schedule_delayed_work(&onkey->work, msecs_to_jiffies(50));
+}
+
+static void da9052_onkey_work(struct work_struct *work)
+{
+	struct da9052_onkey *onkey = container_of(work, struct da9052_onkey,
+						  work.work);
+
+	da9052_onkey_query(onkey);
+}
+
+static irqreturn_t da9052_onkey_irq(int irq, void *data)
+{
+	struct da9052_onkey *onkey = data;
+
+	da9052_onkey_query(onkey);
+
+	return IRQ_HANDLED;
+}
+
+static int __devinit da9052_onkey_probe(struct platform_device *pdev)
+{
+	struct da9052 *da9052 = dev_get_drvdata(pdev->dev.parent);
+	struct da9052_onkey *onkey;
+	struct input_dev *input_dev;
+	int irq;
+	int error;
+
+	if (!da9052) {
+		dev_err(&pdev->dev, "Failed to get the driver's data\n");
+		return -EINVAL;
+	}
+
+	irq = platform_get_irq_byname(pdev, "ONKEY");
+	if (irq < 0) {
+		dev_err(&pdev->dev,
+			"Failed to get an IRQ for input device, %d\n", irq);
+		return -EINVAL;
+	}
+
+	onkey = kzalloc(sizeof(*onkey), GFP_KERNEL);
+	input_dev = input_allocate_device();
+	if (!onkey || !input_dev) {
+		dev_err(&pdev->dev, "Failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	onkey->input = input_dev;
+	onkey->da9052 = da9052;
+	onkey->irq = irq;
+	INIT_DELAYED_WORK(&onkey->work, da9052_onkey_work);
+
+	input_dev->name = "da9052-onkey";
+	input_dev->phys = "da9052-onkey/input0";
+	input_dev->dev.parent = &pdev->dev;
+
+	input_dev->evbit[0] = BIT_MASK(EV_KEY);
+	__set_bit(KEY_POWER, input_dev->keybit);
+
+	error = request_threaded_irq(onkey->irq, NULL, da9052_onkey_irq,
+				     IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+				     "ONKEY", onkey);
+	if (error < 0) {
+		dev_err(onkey->da9052->dev,
+			"Failed to register ONKEY IRQ %d, error = %d\n",
+			onkey->irq, error);
+		goto err_free_mem;
+	}
+
+	error = input_register_device(onkey->input);
+	if (error) {
+		dev_err(&pdev->dev, "Unable to register input device, %d\n",
+			error);
+		goto err_free_irq;
+	}
+
+	platform_set_drvdata(pdev, onkey);
+	return 0;
+
+err_free_irq:
+	free_irq(onkey->irq, onkey);
+	cancel_delayed_work_sync(&onkey->work);
+err_free_mem:
+	input_free_device(input_dev);
+	kfree(onkey);
+
+	return error;
+}
+
+static int __devexit da9052_onkey_remove(struct platform_device *pdev)
+{
+	struct da9052_onkey *onkey = platform_get_drvdata(pdev);
+
+	free_irq(onkey->irq, onkey);
+	cancel_delayed_work_sync(&onkey->work);
+
+	input_unregister_device(onkey->input);
+	kfree(onkey);
+
+	return 0;
+}
+
+static struct platform_driver da9052_onkey_driver = {
+	.probe	= da9052_onkey_probe,
+	.remove	= __devexit_p(da9052_onkey_remove),
+	.driver = {
+		.name	= "da9052-onkey",
+		.owner	= THIS_MODULE,
+	},
+};
+module_platform_driver(da9052_onkey_driver);
+
+MODULE_AUTHOR("David Dajun Chen <[e-mail]>");
+MODULE_DESCRIPTION("Onkey driver for DA9052");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:da9052-onkey");