/*
 * Base driver for Maxim MAX8925
 *
 * Copyright (C) 2009 Marvell International Ltd.
 *	Haojian Zhuang <haojian.zhuang@marvell.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/kernel.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/mfd/core.h>
#include <linux/mfd/max8925.h>

#define IRQ_MODE_STATUS		0
#define IRQ_MODE_MASK		1

static struct resource backlight_resources[] = {
	{
		.name	= "max8925-backlight",
		.start	= MAX8925_WLED_MODE_CNTL,
		.end	= MAX8925_WLED_CNTL,
		.flags	= IORESOURCE_IO,
	},
};

static struct mfd_cell backlight_devs[] = {
	{
		.name		= "max8925-backlight",
		.num_resources	= 1,
		.resources	= &backlight_resources[0],
		.id		= -1,
	},
};

static struct resource touch_resources[] = {
	{
		.name	= "max8925-tsc",
		.start	= MAX8925_TSC_IRQ,
		.end	= MAX8925_ADC_RES_END,
		.flags	= IORESOURCE_IO,
	},
};

static struct mfd_cell touch_devs[] = {
	{
		.name		= "max8925-touch",
		.num_resources	= 1,
		.resources	= &touch_resources[0],
		.id		= -1,
	},
};

#define MAX8925_REG_RESOURCE(_start, _end)	\
{						\
	.start	= MAX8925_##_start,		\
	.end	= MAX8925_##_end,		\
	.flags	= IORESOURCE_IO,		\
}

static struct resource regulator_resources[] = {
	MAX8925_REG_RESOURCE(SDCTL1, SDCTL1),
	MAX8925_REG_RESOURCE(SDCTL2, SDCTL2),
	MAX8925_REG_RESOURCE(SDCTL3, SDCTL3),
	MAX8925_REG_RESOURCE(LDOCTL1, LDOCTL1),
	MAX8925_REG_RESOURCE(LDOCTL2, LDOCTL2),
	MAX8925_REG_RESOURCE(LDOCTL3, LDOCTL3),
	MAX8925_REG_RESOURCE(LDOCTL4, LDOCTL4),
	MAX8925_REG_RESOURCE(LDOCTL5, LDOCTL5),
	MAX8925_REG_RESOURCE(LDOCTL6, LDOCTL6),
	MAX8925_REG_RESOURCE(LDOCTL7, LDOCTL7),
	MAX8925_REG_RESOURCE(LDOCTL8, LDOCTL8),
	MAX8925_REG_RESOURCE(LDOCTL9, LDOCTL9),
	MAX8925_REG_RESOURCE(LDOCTL10, LDOCTL10),
	MAX8925_REG_RESOURCE(LDOCTL11, LDOCTL11),
	MAX8925_REG_RESOURCE(LDOCTL12, LDOCTL12),
	MAX8925_REG_RESOURCE(LDOCTL13, LDOCTL13),
	MAX8925_REG_RESOURCE(LDOCTL14, LDOCTL14),
	MAX8925_REG_RESOURCE(LDOCTL15, LDOCTL15),
	MAX8925_REG_RESOURCE(LDOCTL16, LDOCTL16),
	MAX8925_REG_RESOURCE(LDOCTL17, LDOCTL17),
	MAX8925_REG_RESOURCE(LDOCTL18, LDOCTL18),
	MAX8925_REG_RESOURCE(LDOCTL19, LDOCTL19),
	MAX8925_REG_RESOURCE(LDOCTL20, LDOCTL20),
};

#define MAX8925_REG_DEVS(_id)						\
{									\
	.name		= "max8925-regulator",				\
	.num_resources	= 1,						\
	.resources	= &regulator_resources[MAX8925_ID_##_id],	\
	.id		= MAX8925_ID_##_id,				\
}

static struct mfd_cell regulator_devs[] = {
	MAX8925_REG_DEVS(SD1),
	MAX8925_REG_DEVS(SD2),
	MAX8925_REG_DEVS(SD3),
	MAX8925_REG_DEVS(LDO1),
	MAX8925_REG_DEVS(LDO2),
	MAX8925_REG_DEVS(LDO3),
	MAX8925_REG_DEVS(LDO4),
	MAX8925_REG_DEVS(LDO5),
	MAX8925_REG_DEVS(LDO6),
	MAX8925_REG_DEVS(LDO7),
	MAX8925_REG_DEVS(LDO8),
	MAX8925_REG_DEVS(LDO9),
	MAX8925_REG_DEVS(LDO10),
	MAX8925_REG_DEVS(LDO11),
	MAX8925_REG_DEVS(LDO12),
	MAX8925_REG_DEVS(LDO13),
	MAX8925_REG_DEVS(LDO14),
	MAX8925_REG_DEVS(LDO15),
	MAX8925_REG_DEVS(LDO16),
	MAX8925_REG_DEVS(LDO17),
	MAX8925_REG_DEVS(LDO18),
	MAX8925_REG_DEVS(LDO19),
	MAX8925_REG_DEVS(LDO20),
};

static int __get_irq_offset(struct max8925_chip *chip, int irq, int mode,
			    int *offset, int *bit)
{
	if (!offset || !bit)
		return -EINVAL;

	switch (chip->chip_id) {
	case MAX8925_GPM:
		*bit = irq % BITS_PER_BYTE;
		if (irq < (BITS_PER_BYTE << 1)) {	/* irq = [0,15] */
			*offset = (mode) ? MAX8925_CHG_IRQ1_MASK
				: MAX8925_CHG_IRQ1;
			if (irq >= BITS_PER_BYTE)
				(*offset)++;
		} else {				/* irq = [16,31] */
			*offset = (mode) ? MAX8925_ON_OFF_IRQ1_MASK
				: MAX8925_ON_OFF_IRQ1;
			if (irq >= (BITS_PER_BYTE * 3))
				(*offset)++;
		}
		break;
	case MAX8925_ADC:
		*bit = irq % BITS_PER_BYTE;
		*offset = (mode) ? MAX8925_TSC_IRQ_MASK : MAX8925_TSC_IRQ;
		break;
	default:
		goto out;
	}
	return 0;
out:
	dev_err(chip->dev, "Wrong irq #%d is assigned\n", irq);
	return -EINVAL;
}

static int __check_irq(int irq)
{
	if ((irq < 0) || (irq >= MAX8925_NUM_IRQ))
		return -EINVAL;
	return 0;
}

int max8925_mask_irq(struct max8925_chip *chip, int irq)
{
	int offset, bit, ret;

	ret = __get_irq_offset(chip, irq, IRQ_MODE_MASK, &offset, &bit);
	if (ret < 0)
		return ret;
	ret = max8925_set_bits(chip->i2c, offset, 1 << bit, 1 << bit);
	return ret;
}

int max8925_unmask_irq(struct max8925_chip *chip, int irq)
{
	int offset, bit, ret;

	ret = __get_irq_offset(chip, irq, IRQ_MODE_MASK, &offset, &bit);
	if (ret < 0)
		return ret;
	ret = max8925_set_bits(chip->i2c, offset, 1 << bit, 0);
	return ret;
}

#define INT_STATUS_NUM		(MAX8925_NUM_IRQ / BITS_PER_BYTE)

static irqreturn_t max8925_irq_thread(int irq, void *data)
{
	struct max8925_chip *chip = data;
	unsigned long irq_status[INT_STATUS_NUM];
	unsigned char status_buf[INT_STATUS_NUM << 1];
	int i, ret;

	memset(irq_status, 0, sizeof(unsigned long) * INT_STATUS_NUM);

	/* all these interrupt status registers are read-only */
	switch (chip->chip_id) {
	case MAX8925_GPM:
		ret = max8925_bulk_read(chip->i2c, MAX8925_CHG_IRQ1,
					4, status_buf);
		if (ret < 0)
			goto out;
		ret = max8925_bulk_read(chip->i2c, MAX8925_ON_OFF_IRQ1,
					2, &status_buf[4]);
		if (ret < 0)
			goto out;
		ret = max8925_bulk_read(chip->i2c, MAX8925_ON_OFF_IRQ2,
					2, &status_buf[6]);
		if (ret < 0)
			goto out;
		/* clear masked interrupt status */
		status_buf[0] &= (~status_buf[2] & CHG_IRQ1_MASK);
		irq_status[0] |= status_buf[0];
		status_buf[1] &= (~status_buf[3] & CHG_IRQ2_MASK);
		irq_status[0] |= (status_buf[1] << BITS_PER_BYTE);
		status_buf[4] &= (~status_buf[5] & ON_OFF_IRQ1_MASK);
		irq_status[0] |= (status_buf[4] << (BITS_PER_BYTE * 2));
		status_buf[6] &= (~status_buf[7] & ON_OFF_IRQ2_MASK);
		irq_status[0] |= (status_buf[6] << (BITS_PER_BYTE * 3));
		break;
	case MAX8925_ADC:
		ret = max8925_bulk_read(chip->i2c, MAX8925_TSC_IRQ,
					2, status_buf);
		if (ret < 0)
			goto out;
		/* clear masked interrupt status */
		status_buf[0] &= (~status_buf[1] & TSC_IRQ_MASK);
		irq_status[0] |= status_buf[0];
		break;
	default:
		goto out;
	}

	for_each_bit(i, &irq_status[0], MAX8925_NUM_IRQ) {
		clear_bit(i, irq_status);
		dev_dbg(chip->dev, "Servicing IRQ #%d in %s\n", i, chip->name);

		mutex_lock(&chip->irq_lock);
		if (chip->irq[i].handler)
			chip->irq[i].handler(i, chip->irq[i].data);
		else {
			max8925_mask_irq(chip, i);
			dev_err(chip->dev, "Noboday cares IRQ #%d in %s. "
				"Now mask it.\n", i, chip->name);
		}
		mutex_unlock(&chip->irq_lock);
	}
out:
	return IRQ_HANDLED;
}

int max8925_request_irq(struct max8925_chip *chip, int irq,
			irq_handler_t handler, void *data)
{
	if ((__check_irq(irq) < 0) || !handler)
		return -EINVAL;

	mutex_lock(&chip->irq_lock);
	chip->irq[irq].handler = handler;
	chip->irq[irq].data = data;
	mutex_unlock(&chip->irq_lock);
	return 0;
}
EXPORT_SYMBOL(max8925_request_irq);

int max8925_free_irq(struct max8925_chip *chip, int irq)
{
	if (__check_irq(irq) < 0)
		return -EINVAL;

	mutex_lock(&chip->irq_lock);
	chip->irq[irq].handler = NULL;
	chip->irq[irq].data = NULL;
	mutex_unlock(&chip->irq_lock);
	return 0;
}
EXPORT_SYMBOL(max8925_free_irq);

static int __devinit device_gpm_init(struct max8925_chip *chip,
				      struct i2c_client *i2c,
				      struct max8925_platform_data *pdata)
{
	int ret;

	/* mask all IRQs */
	ret = max8925_set_bits(i2c, MAX8925_CHG_IRQ1_MASK, 0x7, 0x7);
	if (ret < 0)
		goto out;
	ret = max8925_set_bits(i2c, MAX8925_CHG_IRQ2_MASK, 0xff, 0xff);
	if (ret < 0)
		goto out;
	ret = max8925_set_bits(i2c, MAX8925_ON_OFF_IRQ1_MASK, 0xff, 0xff);
	if (ret < 0)
		goto out;
	ret = max8925_set_bits(i2c, MAX8925_ON_OFF_IRQ2_MASK, 0x3, 0x3);
	if (ret < 0)
		goto out;

	chip->name = "GPM";
	memset(chip->irq, 0, sizeof(struct max8925_irq) * MAX8925_NUM_IRQ);
	ret = request_threaded_irq(i2c->irq, NULL, max8925_irq_thread,
				IRQF_ONESHOT | IRQF_TRIGGER_LOW,
				"max8925-gpm", chip);
	if (ret < 0) {
		dev_err(chip->dev, "Failed to request IRQ #%d.\n", i2c->irq);
		goto out;
	}
	chip->chip_irq = i2c->irq;

	/* enable hard-reset for ONKEY power-off */
	max8925_set_bits(i2c, MAX8925_SYSENSEL, 0x80, 0x80);

	ret = mfd_add_devices(chip->dev, 0, &regulator_devs[0],
			      ARRAY_SIZE(regulator_devs),
			      &regulator_resources[0], 0);
	if (ret < 0) {
		dev_err(chip->dev, "Failed to add regulator subdev\n");
		goto out_irq;
	}

	if (pdata && pdata->backlight) {
		ret = mfd_add_devices(chip->dev, 0, &backlight_devs[0],
				      ARRAY_SIZE(backlight_devs),
				      &backlight_resources[0], 0);
		if (ret < 0) {
			dev_err(chip->dev, "Failed to add backlight subdev\n");
			goto out_dev;
		}
	}
	return 0;
out_dev:
	mfd_remove_devices(chip->dev);
out_irq:
	if (chip->chip_irq)
		free_irq(chip->chip_irq, chip);
out:
	return ret;
}

static int __devinit device_adc_init(struct max8925_chip *chip,
				     struct i2c_client *i2c,
				     struct max8925_platform_data *pdata)
{
	int ret;

	/* mask all IRQs */
	ret = max8925_set_bits(i2c, MAX8925_TSC_IRQ_MASK, 3, 3);

	chip->name = "ADC";
	memset(chip->irq, 0, sizeof(struct max8925_irq) * MAX8925_NUM_IRQ);
	ret = request_threaded_irq(i2c->irq, NULL, max8925_irq_thread,
				IRQF_ONESHOT | IRQF_TRIGGER_LOW,
				"max8925-adc", chip);
	if (ret < 0) {
		dev_err(chip->dev, "Failed to request IRQ #%d.\n", i2c->irq);
		goto out;
	}
	chip->chip_irq = i2c->irq;

	if (pdata && pdata->touch) {
		ret = mfd_add_devices(chip->dev, 0, &touch_devs[0],
				      ARRAY_SIZE(touch_devs),
				      &touch_resources[0], 0);
		if (ret < 0) {
			dev_err(chip->dev, "Failed to add touch subdev\n");
			goto out_irq;
		}
	}
	return 0;
out_irq:
	if (chip->chip_irq)
		free_irq(chip->chip_irq, chip);
out:
	return ret;
}

int __devinit max8925_device_init(struct max8925_chip *chip,
				  struct max8925_platform_data *pdata)
{
	switch (chip->chip_id) {
	case MAX8925_GPM:
		device_gpm_init(chip, chip->i2c, pdata);
		break;
	case MAX8925_ADC:
		device_adc_init(chip, chip->i2c, pdata);
		break;
	}
	return 0;
}

void max8925_device_exit(struct max8925_chip *chip)
{
	if (chip->chip_irq >= 0)
		free_irq(chip->chip_irq, chip);
	mfd_remove_devices(chip->dev);
}

MODULE_DESCRIPTION("PMIC Driver for Maxim MAX8925");
MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com");
MODULE_LICENSE("GPL");