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Commit 0baf81ba authored by Kim Kyuwon's avatar Kim Kyuwon Committed by Dmitry Torokhov
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Input: add driver for Maxim MAX7359 key switch controller



The Maxim MAX7359 is a I2C interfaced key switch controller which
provides microprocessors with management of up to 64 key switches.
This patch adds support for the MAX7359 key switch controller.

Signed-off-by: default avatarKim Kyuwon <q1.kim@samsung.com>
Reviewed-by: default avatarTrilok Soni <soni.trilok@gmail.com>
Signed-off-by: default avatarDmitry Torokhov <dtor@mail.ru>
parent 88751dd6
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+11 −0
Original line number Diff line number Diff line
@@ -261,6 +261,17 @@ config KEYBOARD_MAPLE
	  To compile this driver as a module, choose M here: the
	  module will be called maple_keyb.

config KEYBOARD_MAX7359
	tristate "Maxim MAX7359 Key Switch Controller"
	depends on I2C
	help
	  If you say yes here you get support for the Maxim MAX7359 Key
	  Switch Controller chip. This providers microprocessors with
	  management of up to 64 key switches

	  To compile this driver as a module, choose M here: the
	  module will be called max7359_keypad.

config KEYBOARD_NEWTON
	tristate "Newton keyboard"
	select SERIO
+1 −0
Original line number Diff line number Diff line
@@ -22,6 +22,7 @@ obj-$(CONFIG_KEYBOARD_LM8323) += lm8323.o
obj-$(CONFIG_KEYBOARD_LOCOMO)		+= locomokbd.o
obj-$(CONFIG_KEYBOARD_MAPLE)		+= maple_keyb.o
obj-$(CONFIG_KEYBOARD_MATRIX)		+= matrix_keypad.o
obj-$(CONFIG_KEYBOARD_MAX7359)		+= max7359_keypad.o
obj-$(CONFIG_KEYBOARD_NEWTON)		+= newtonkbd.o
obj-$(CONFIG_KEYBOARD_OMAP)		+= omap-keypad.o
obj-$(CONFIG_KEYBOARD_OPENCORES)	+= opencores-kbd.o
+352 −0
Original line number Diff line number Diff line
/*
 * max7359_keypad.c - MAX7359 Key Switch Controller Driver
 *
 * Copyright (C) 2009 Samsung Electronics
 * Kim Kyuwon <q1.kim@samsung.com>
 *
 * Based on pxa27x_keypad.c
 *
 * 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.
 *
 * Datasheet: http://www.maxim-ic.com/quick_view2.cfm/qv_pk/5456
 */

#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/input/matrix_keypad.h>

#define MAX7359_MAX_KEY_ROWS	8
#define MAX7359_MAX_KEY_COLS	8
#define MAX7359_MAX_KEY_NUM	(MAX7359_MAX_KEY_ROWS * MAX7359_MAX_KEY_COLS)
#define MAX7359_ROW_SHIFT	3

/*
 * MAX7359 registers
 */
#define MAX7359_REG_KEYFIFO	0x00
#define MAX7359_REG_CONFIG	0x01
#define MAX7359_REG_DEBOUNCE	0x02
#define MAX7359_REG_INTERRUPT	0x03
#define MAX7359_REG_PORTS	0x04
#define MAX7359_REG_KEYREP	0x05
#define MAX7359_REG_SLEEP	0x06

/*
 * Configuration register bits
 */
#define MAX7359_CFG_SLEEP	(1 << 7)
#define MAX7359_CFG_INTERRUPT	(1 << 5)
#define MAX7359_CFG_KEY_RELEASE	(1 << 3)
#define MAX7359_CFG_WAKEUP	(1 << 1)
#define MAX7359_CFG_TIMEOUT	(1 << 0)

/*
 * Autosleep register values (ms)
 */
#define MAX7359_AUTOSLEEP_8192	0x01
#define MAX7359_AUTOSLEEP_4096	0x02
#define MAX7359_AUTOSLEEP_2048	0x03
#define MAX7359_AUTOSLEEP_1024	0x04
#define MAX7359_AUTOSLEEP_512	0x05
#define MAX7359_AUTOSLEEP_256	0x06

struct max7359_keypad {
	/* matrix key code map */
	unsigned short keycodes[MAX7359_MAX_KEY_NUM];

	struct work_struct work;

	struct input_dev *input_dev;
	struct i2c_client *client;

	u32 irq;
};

static int max7359_write_reg(struct i2c_client *client, u8 reg, u8 val)
{
	int ret = i2c_smbus_write_byte_data(client, reg, val);

	if (ret < 0)
		dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
			__func__, reg, val, ret);
	return ret;
}

static int max7359_read_reg(struct i2c_client *client, int reg)
{
	int ret = i2c_smbus_read_byte_data(client, reg);

	if (ret < 0)
		dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
			__func__, reg, ret);
	return ret;
}

static void max7359_build_keycode(struct max7359_keypad *keypad,
				const struct matrix_keymap_data *keymap_data)
{
	struct input_dev *input_dev = keypad->input_dev;
	int i;

	for (i = 0; i < keymap_data->keymap_size; i++) {
		unsigned int key = keymap_data->keymap[i];
		unsigned int row = KEY_ROW(key);
		unsigned int col = KEY_COL(key);
		unsigned int scancode = MATRIX_SCAN_CODE(row, col,
						MAX7359_ROW_SHIFT);
		unsigned short keycode = KEY_VAL(key);

		keypad->keycodes[scancode] = keycode;
		__set_bit(keycode, input_dev->keybit);
	}
	__clear_bit(KEY_RESERVED, input_dev->keybit);
}

static void max7359_worker(struct work_struct *work)
{
	struct max7359_keypad *keypad =
			container_of(work, struct max7359_keypad, work);
	struct input_dev *input_dev = keypad->input_dev;
	int val, row, col, release, code;

	val = max7359_read_reg(keypad->client, MAX7359_REG_KEYFIFO);
	row = val & 0x7;
	col = (val >> 3) & 0x7;
	release = val & 0x40;

	code = MATRIX_SCAN_CODE(row, col, MAX7359_ROW_SHIFT);

	input_event(input_dev, EV_MSC, MSC_SCAN, code);
	input_report_key(input_dev, keypad->keycodes[code], !release);
	input_sync(input_dev);

	enable_irq(keypad->irq);

	dev_dbg(&keypad->client->dev, "key[%d:%d] %s\n", row, col,
					(release ? "release" : "press"));
}

static irqreturn_t max7359_interrupt(int irq, void *dev_id)
{
	struct max7359_keypad *keypad = dev_id;

	if (!work_pending(&keypad->work)) {
		disable_irq_nosync(keypad->irq);
		schedule_work(&keypad->work);
	}

	return IRQ_HANDLED;
}

/*
 * Let MAX7359 fall into a deep sleep:
 * If no keys are pressed, enter sleep mode for 8192 ms. And if any
 * key is pressed, the MAX7359 returns to normal operating mode.
 */
static inline void max7359_fall_deepsleep(struct i2c_client *client)
{
	max7359_write_reg(client, MAX7359_REG_SLEEP, MAX7359_AUTOSLEEP_8192);
}

/*
 * Let MAX7359 take a catnap:
 * Autosleep just for 256 ms.
 */
static inline void max7359_take_catnap(struct i2c_client *client)
{
	max7359_write_reg(client, MAX7359_REG_SLEEP, MAX7359_AUTOSLEEP_256);
}

static int max7359_open(struct input_dev *dev)
{
	struct max7359_keypad *keypad = input_get_drvdata(dev);

	max7359_take_catnap(keypad->client);

	return 0;
}

static void max7359_close(struct input_dev *dev)
{
	struct max7359_keypad *keypad = input_get_drvdata(dev);

	max7359_fall_deepsleep(keypad->client);
}

static void max7359_initialize(struct i2c_client *client)
{
	max7359_write_reg(client, MAX7359_REG_CONFIG,
		MAX7359_CFG_INTERRUPT | /* Irq clears after host read */
		MAX7359_CFG_KEY_RELEASE | /* Key release enable */
		MAX7359_CFG_WAKEUP); /* Key press wakeup enable */

	/* Full key-scan functionality */
	max7359_write_reg(client, MAX7359_REG_DEBOUNCE, 0x1F);

	/* nINT asserts every debounce cycles */
	max7359_write_reg(client, MAX7359_REG_INTERRUPT, 0x01);

	max7359_fall_deepsleep(client);
}

static int __devinit max7359_probe(struct i2c_client *client,
					const struct i2c_device_id *id)
{
	const struct matrix_keymap_data *keymap_data = client->dev.platform_data;
	struct max7359_keypad *keypad;
	struct input_dev *input_dev;
	int ret;
	int error;

	if (!client->irq) {
		dev_err(&client->dev, "The irq number should not be zero\n");
		return -EINVAL;
	}

	/* Detect MAX7359: The initial Keys FIFO value is '0x3F' */
	ret = max7359_read_reg(client, MAX7359_REG_KEYFIFO);
	if (ret < 0) {
		dev_err(&client->dev, "failed to detect device\n");
		return -ENODEV;
	}

	dev_dbg(&client->dev, "keys FIFO is 0x%02x\n", ret);

	keypad = kzalloc(sizeof(struct max7359_keypad), GFP_KERNEL);
	input_dev = input_allocate_device();
	if (!keypad || !input_dev) {
		dev_err(&client->dev, "failed to allocate memory\n");
		error = -ENOMEM;
		goto failed_free_mem;
	}

	keypad->client = client;
	keypad->input_dev = input_dev;
	keypad->irq = client->irq;
	INIT_WORK(&keypad->work, max7359_worker);

	input_dev->name = client->name;
	input_dev->id.bustype = BUS_I2C;
	input_dev->open = max7359_open;
	input_dev->close = max7359_close;
	input_dev->dev.parent = &client->dev;

	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
	input_dev->keycodesize = sizeof(keypad->keycodes[0]);
	input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
	input_dev->keycode = keypad->keycodes;

	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
	input_set_drvdata(input_dev, keypad);

	max7359_build_keycode(keypad, keymap_data);

	error = request_irq(keypad->irq, max7359_interrupt,
			    IRQF_TRIGGER_LOW, client->name, keypad);
	if (error) {
		dev_err(&client->dev, "failed to register interrupt\n");
		goto failed_free_mem;
	}

	/* Register the input device */
	error = input_register_device(input_dev);
	if (error) {
		dev_err(&client->dev, "failed to register input device\n");
		goto failed_free_irq;
	}

	/* Initialize MAX7359 */
	max7359_initialize(client);

	i2c_set_clientdata(client, keypad);
	device_init_wakeup(&client->dev, 1);

	return 0;

failed_free_irq:
	free_irq(keypad->irq, keypad);
failed_free_mem:
	input_free_device(input_dev);
	kfree(keypad);
	return error;
}

static int __devexit max7359_remove(struct i2c_client *client)
{
	struct max7359_keypad *keypad = i2c_get_clientdata(client);

	cancel_work_sync(&keypad->work);
	input_unregister_device(keypad->input_dev);
	free_irq(keypad->irq, keypad);
	i2c_set_clientdata(client, NULL);
	kfree(keypad);

	return 0;
}

#ifdef CONFIG_PM
static int max7359_suspend(struct i2c_client *client, pm_message_t mesg)
{
	struct max7359_keypad *keypad = i2c_get_clientdata(client);

	max7359_fall_deepsleep(client);

	if (device_may_wakeup(&client->dev))
		enable_irq_wake(keypad->irq);

	return 0;
}

static int max7359_resume(struct i2c_client *client)
{
	struct max7359_keypad *keypad = i2c_get_clientdata(client);

	if (device_may_wakeup(&client->dev))
		disable_irq_wake(keypad->irq);

	/* Restore the default setting */
	max7359_take_catnap(client);

	return 0;
}
#else
#define max7359_suspend	NULL
#define max7359_resume	NULL
#endif

static const struct i2c_device_id max7359_ids[] = {
	{ "max7359", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, max7359_ids);

static struct i2c_driver max7359_i2c_driver = {
	.driver = {
		.name = "max7359",
	},
	.probe		= max7359_probe,
	.remove		= __devexit_p(max7359_remove),
	.suspend	= max7359_suspend,
	.resume		= max7359_resume,
	.id_table	= max7359_ids,
};

static int __init max7359_init(void)
{
	return i2c_add_driver(&max7359_i2c_driver);
}
module_init(max7359_init);

static void __exit max7359_exit(void)
{
	i2c_del_driver(&max7359_i2c_driver);
}
module_exit(max7359_exit);

MODULE_AUTHOR("Kim Kyuwon <q1.kim@samsung.com>");
MODULE_DESCRIPTION("MAX7359 Key Switch Controller Driver");
MODULE_LICENSE("GPL v2");