/*
 * MFD driver for TWL6040 audio device
 *
 * Authors:	Misael Lopez Cruz <misael.lopez@ti.com>
 *		Jorge Eduardo Candelaria <jorge.candelaria@ti.com>
 *		Peter Ujfalusi <peter.ujfalusi@ti.com>
 *
 * Copyright:	(C) 2011 Texas Instruments, Inc.
 *
 * 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.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/regmap.h>
#include <linux/err.h>
#include <linux/mfd/core.h>
#include <linux/mfd/twl6040.h>

#define VIBRACTRL_MEMBER(reg) ((reg == TWL6040_REG_VIBCTLL) ? 0 : 1)

int twl6040_reg_read(struct twl6040 *twl6040, unsigned int reg)
{
	int ret;
	unsigned int val;

	mutex_lock(&twl6040->io_mutex);
	/* Vibra control registers from cache */
	if (unlikely(reg == TWL6040_REG_VIBCTLL ||
		     reg == TWL6040_REG_VIBCTLR)) {
		val = twl6040->vibra_ctrl_cache[VIBRACTRL_MEMBER(reg)];
	} else {
		ret = regmap_read(twl6040->regmap, reg, &val);
		if (ret < 0) {
			mutex_unlock(&twl6040->io_mutex);
			return ret;
		}
	}
	mutex_unlock(&twl6040->io_mutex);

	return val;
}
EXPORT_SYMBOL(twl6040_reg_read);

int twl6040_reg_write(struct twl6040 *twl6040, unsigned int reg, u8 val)
{
	int ret;

	mutex_lock(&twl6040->io_mutex);
	ret = regmap_write(twl6040->regmap, reg, val);
	/* Cache the vibra control registers */
	if (reg == TWL6040_REG_VIBCTLL || reg == TWL6040_REG_VIBCTLR)
		twl6040->vibra_ctrl_cache[VIBRACTRL_MEMBER(reg)] = val;
	mutex_unlock(&twl6040->io_mutex);

	return ret;
}
EXPORT_SYMBOL(twl6040_reg_write);

int twl6040_set_bits(struct twl6040 *twl6040, unsigned int reg, u8 mask)
{
	int ret;

	mutex_lock(&twl6040->io_mutex);
	ret = regmap_update_bits(twl6040->regmap, reg, mask, mask);
	mutex_unlock(&twl6040->io_mutex);
	return ret;
}
EXPORT_SYMBOL(twl6040_set_bits);

int twl6040_clear_bits(struct twl6040 *twl6040, unsigned int reg, u8 mask)
{
	int ret;

	mutex_lock(&twl6040->io_mutex);
	ret = regmap_update_bits(twl6040->regmap, reg, mask, 0);
	mutex_unlock(&twl6040->io_mutex);
	return ret;
}
EXPORT_SYMBOL(twl6040_clear_bits);

/* twl6040 codec manual power-up sequence */
static int twl6040_power_up(struct twl6040 *twl6040)
{
	u8 ldoctl, ncpctl, lppllctl;
	int ret;

	/* enable high-side LDO, reference system and internal oscillator */
	ldoctl = TWL6040_HSLDOENA | TWL6040_REFENA | TWL6040_OSCENA;
	ret = twl6040_reg_write(twl6040, TWL6040_REG_LDOCTL, ldoctl);
	if (ret)
		return ret;
	usleep_range(10000, 10500);

	/* enable negative charge pump */
	ncpctl = TWL6040_NCPENA;
	ret = twl6040_reg_write(twl6040, TWL6040_REG_NCPCTL, ncpctl);
	if (ret)
		goto ncp_err;
	usleep_range(1000, 1500);

	/* enable low-side LDO */
	ldoctl |= TWL6040_LSLDOENA;
	ret = twl6040_reg_write(twl6040, TWL6040_REG_LDOCTL, ldoctl);
	if (ret)
		goto lsldo_err;
	usleep_range(1000, 1500);

	/* enable low-power PLL */
	lppllctl = TWL6040_LPLLENA;
	ret = twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL, lppllctl);
	if (ret)
		goto lppll_err;
	usleep_range(5000, 5500);

	/* disable internal oscillator */
	ldoctl &= ~TWL6040_OSCENA;
	ret = twl6040_reg_write(twl6040, TWL6040_REG_LDOCTL, ldoctl);
	if (ret)
		goto osc_err;

	return 0;

osc_err:
	lppllctl &= ~TWL6040_LPLLENA;
	twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL, lppllctl);
lppll_err:
	ldoctl &= ~TWL6040_LSLDOENA;
	twl6040_reg_write(twl6040, TWL6040_REG_LDOCTL, ldoctl);
lsldo_err:
	ncpctl &= ~TWL6040_NCPENA;
	twl6040_reg_write(twl6040, TWL6040_REG_NCPCTL, ncpctl);
ncp_err:
	ldoctl &= ~(TWL6040_HSLDOENA | TWL6040_REFENA | TWL6040_OSCENA);
	twl6040_reg_write(twl6040, TWL6040_REG_LDOCTL, ldoctl);

	return ret;
}

/* twl6040 manual power-down sequence */
static void twl6040_power_down(struct twl6040 *twl6040)
{
	u8 ncpctl, ldoctl, lppllctl;

	ncpctl = twl6040_reg_read(twl6040, TWL6040_REG_NCPCTL);
	ldoctl = twl6040_reg_read(twl6040, TWL6040_REG_LDOCTL);
	lppllctl = twl6040_reg_read(twl6040, TWL6040_REG_LPPLLCTL);

	/* enable internal oscillator */
	ldoctl |= TWL6040_OSCENA;
	twl6040_reg_write(twl6040, TWL6040_REG_LDOCTL, ldoctl);
	usleep_range(1000, 1500);

	/* disable low-power PLL */
	lppllctl &= ~TWL6040_LPLLENA;
	twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL, lppllctl);

	/* disable low-side LDO */
	ldoctl &= ~TWL6040_LSLDOENA;
	twl6040_reg_write(twl6040, TWL6040_REG_LDOCTL, ldoctl);

	/* disable negative charge pump */
	ncpctl &= ~TWL6040_NCPENA;
	twl6040_reg_write(twl6040, TWL6040_REG_NCPCTL, ncpctl);

	/* disable high-side LDO, reference system and internal oscillator */
	ldoctl &= ~(TWL6040_HSLDOENA | TWL6040_REFENA | TWL6040_OSCENA);
	twl6040_reg_write(twl6040, TWL6040_REG_LDOCTL, ldoctl);
}

static irqreturn_t twl6040_naudint_handler(int irq, void *data)
{
	struct twl6040 *twl6040 = data;
	u8 intid, status;

	intid = twl6040_reg_read(twl6040, TWL6040_REG_INTID);

	if (intid & TWL6040_READYINT)
		complete(&twl6040->ready);

	if (intid & TWL6040_THINT) {
		status = twl6040_reg_read(twl6040, TWL6040_REG_STATUS);
		if (status & TWL6040_TSHUTDET) {
			dev_warn(twl6040->dev,
				 "Thermal shutdown, powering-off");
			twl6040_power(twl6040, 0);
		} else {
			dev_warn(twl6040->dev,
				 "Leaving thermal shutdown, powering-on");
			twl6040_power(twl6040, 1);
		}
	}

	return IRQ_HANDLED;
}

static int twl6040_power_up_completion(struct twl6040 *twl6040,
				       int naudint)
{
	int time_left;
	u8 intid;

	time_left = wait_for_completion_timeout(&twl6040->ready,
						msecs_to_jiffies(144));
	if (!time_left) {
		intid = twl6040_reg_read(twl6040, TWL6040_REG_INTID);
		if (!(intid & TWL6040_READYINT)) {
			dev_err(twl6040->dev,
				"timeout waiting for READYINT\n");
			return -ETIMEDOUT;
		}
	}

	return 0;
}

int twl6040_power(struct twl6040 *twl6040, int on)
{
	int audpwron = twl6040->audpwron;
	int naudint = twl6040->irq;
	int ret = 0;

	mutex_lock(&twl6040->mutex);

	if (on) {
		/* already powered-up */
		if (twl6040->power_count++)
			goto out;

		if (gpio_is_valid(audpwron)) {
			/* use AUDPWRON line */
			gpio_set_value(audpwron, 1);
			/* wait for power-up completion */
			ret = twl6040_power_up_completion(twl6040, naudint);
			if (ret) {
				dev_err(twl6040->dev,
					"automatic power-down failed\n");
				twl6040->power_count = 0;
				goto out;
			}
		} else {
			/* use manual power-up sequence */
			ret = twl6040_power_up(twl6040);
			if (ret) {
				dev_err(twl6040->dev,
					"manual power-up failed\n");
				twl6040->power_count = 0;
				goto out;
			}
		}
		/* Default PLL configuration after power up */
		twl6040->pll = TWL6040_SYSCLK_SEL_LPPLL;
		twl6040->sysclk = 19200000;
		twl6040->mclk = 32768;
	} else {
		/* already powered-down */
		if (!twl6040->power_count) {
			dev_err(twl6040->dev,
				"device is already powered-off\n");
			ret = -EPERM;
			goto out;
		}

		if (--twl6040->power_count)
			goto out;

		if (gpio_is_valid(audpwron)) {
			/* use AUDPWRON line */
			gpio_set_value(audpwron, 0);

			/* power-down sequence latency */
			usleep_range(500, 700);
		} else {
			/* use manual power-down sequence */
			twl6040_power_down(twl6040);
		}
		twl6040->sysclk = 0;
		twl6040->mclk = 0;
	}

out:
	mutex_unlock(&twl6040->mutex);
	return ret;
}
EXPORT_SYMBOL(twl6040_power);

int twl6040_set_pll(struct twl6040 *twl6040, int pll_id,
		    unsigned int freq_in, unsigned int freq_out)
{
	u8 hppllctl, lppllctl;
	int ret = 0;

	mutex_lock(&twl6040->mutex);

	hppllctl = twl6040_reg_read(twl6040, TWL6040_REG_HPPLLCTL);
	lppllctl = twl6040_reg_read(twl6040, TWL6040_REG_LPPLLCTL);

	/* Force full reconfiguration when switching between PLL */
	if (pll_id != twl6040->pll) {
		twl6040->sysclk = 0;
		twl6040->mclk = 0;
	}

	switch (pll_id) {
	case TWL6040_SYSCLK_SEL_LPPLL:
		/* low-power PLL divider */
		/* Change the sysclk configuration only if it has been canged */
		if (twl6040->sysclk != freq_out) {
			switch (freq_out) {
			case 17640000:
				lppllctl |= TWL6040_LPLLFIN;
				break;
			case 19200000:
				lppllctl &= ~TWL6040_LPLLFIN;
				break;
			default:
				dev_err(twl6040->dev,
					"freq_out %d not supported\n",
					freq_out);
				ret = -EINVAL;
				goto pll_out;
			}
			twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL,
					  lppllctl);
		}

		/* The PLL in use has not been change, we can exit */
		if (twl6040->pll == pll_id)
			break;

		switch (freq_in) {
		case 32768:
			lppllctl |= TWL6040_LPLLENA;
			twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL,
					  lppllctl);
			mdelay(5);
			lppllctl &= ~TWL6040_HPLLSEL;
			twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL,
					  lppllctl);
			hppllctl &= ~TWL6040_HPLLENA;
			twl6040_reg_write(twl6040, TWL6040_REG_HPPLLCTL,
					  hppllctl);
			break;
		default:
			dev_err(twl6040->dev,
				"freq_in %d not supported\n", freq_in);
			ret = -EINVAL;
			goto pll_out;
		}
		break;
	case TWL6040_SYSCLK_SEL_HPPLL:
		/* high-performance PLL can provide only 19.2 MHz */
		if (freq_out != 19200000) {
			dev_err(twl6040->dev,
				"freq_out %d not supported\n", freq_out);
			ret = -EINVAL;
			goto pll_out;
		}

		if (twl6040->mclk != freq_in) {
			hppllctl &= ~TWL6040_MCLK_MSK;

			switch (freq_in) {
			case 12000000:
				/* PLL enabled, active mode */
				hppllctl |= TWL6040_MCLK_12000KHZ |
					    TWL6040_HPLLENA;
				break;
			case 19200000:
				/*
				* PLL disabled
				* (enable PLL if MCLK jitter quality
				*  doesn't meet specification)
				*/
				hppllctl |= TWL6040_MCLK_19200KHZ;
				break;
			case 26000000:
				/* PLL enabled, active mode */
				hppllctl |= TWL6040_MCLK_26000KHZ |
					    TWL6040_HPLLENA;
				break;
			case 38400000:
				/* PLL enabled, active mode */
				hppllctl |= TWL6040_MCLK_38400KHZ |
					    TWL6040_HPLLENA;
				break;
			default:
				dev_err(twl6040->dev,
					"freq_in %d not supported\n", freq_in);
				ret = -EINVAL;
				goto pll_out;
			}

			/*
			 * enable clock slicer to ensure input waveform is
			 * square
			 */
			hppllctl |= TWL6040_HPLLSQRENA;

			twl6040_reg_write(twl6040, TWL6040_REG_HPPLLCTL,
					  hppllctl);
			usleep_range(500, 700);
			lppllctl |= TWL6040_HPLLSEL;
			twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL,
					  lppllctl);
			lppllctl &= ~TWL6040_LPLLENA;
			twl6040_reg_write(twl6040, TWL6040_REG_LPPLLCTL,
					  lppllctl);
		}
		break;
	default:
		dev_err(twl6040->dev, "unknown pll id %d\n", pll_id);
		ret = -EINVAL;
		goto pll_out;
	}

	twl6040->sysclk = freq_out;
	twl6040->mclk = freq_in;
	twl6040->pll = pll_id;

pll_out:
	mutex_unlock(&twl6040->mutex);
	return ret;
}
EXPORT_SYMBOL(twl6040_set_pll);

int twl6040_get_pll(struct twl6040 *twl6040)
{
	if (twl6040->power_count)
		return twl6040->pll;
	else
		return -ENODEV;
}
EXPORT_SYMBOL(twl6040_get_pll);

unsigned int twl6040_get_sysclk(struct twl6040 *twl6040)
{
	return twl6040->sysclk;
}
EXPORT_SYMBOL(twl6040_get_sysclk);

/* Get the combined status of the vibra control register */
int twl6040_get_vibralr_status(struct twl6040 *twl6040)
{
	u8 status;

	status = twl6040->vibra_ctrl_cache[0] | twl6040->vibra_ctrl_cache[1];
	status &= (TWL6040_VIBENA | TWL6040_VIBSEL);

	return status;
}
EXPORT_SYMBOL(twl6040_get_vibralr_status);

static struct resource twl6040_vibra_rsrc[] = {
	{
		.flags = IORESOURCE_IRQ,
	},
};

static struct resource twl6040_codec_rsrc[] = {
	{
		.flags = IORESOURCE_IRQ,
	},
};

static bool twl6040_readable_reg(struct device *dev, unsigned int reg)
{
	/* Register 0 is not readable */
	if (!reg)
		return false;
	return true;
}

static struct regmap_config twl6040_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = TWL6040_REG_STATUS, /* 0x2e */

	.readable_reg = twl6040_readable_reg,
};

static int __devinit twl6040_probe(struct i2c_client *client,
				     const struct i2c_device_id *id)
{
	struct twl6040_platform_data *pdata = client->dev.platform_data;
	struct twl6040 *twl6040;
	struct mfd_cell *cell = NULL;
	int ret, children = 0;

	if (!pdata) {
		dev_err(&client->dev, "Platform data is missing\n");
		return -EINVAL;
	}

	/* In order to operate correctly we need valid interrupt config */
	if (!client->irq || !pdata->irq_base) {
		dev_err(&client->dev, "Invalid IRQ configuration\n");
		return -EINVAL;
	}

	twl6040 = devm_kzalloc(&client->dev, sizeof(struct twl6040),
			       GFP_KERNEL);
	if (!twl6040) {
		ret = -ENOMEM;
		goto err;
	}

	twl6040->regmap = regmap_init_i2c(client, &twl6040_regmap_config);
	if (IS_ERR(twl6040->regmap)) {
		ret = PTR_ERR(twl6040->regmap);
		goto err;
	}

	i2c_set_clientdata(client, twl6040);

	twl6040->dev = &client->dev;
	twl6040->irq = client->irq;
	twl6040->irq_base = pdata->irq_base;

	mutex_init(&twl6040->mutex);
	mutex_init(&twl6040->io_mutex);
	init_completion(&twl6040->ready);

	twl6040->rev = twl6040_reg_read(twl6040, TWL6040_REG_ASICREV);

	/* ERRATA: Automatic power-up is not possible in ES1.0 */
	if (twl6040_get_revid(twl6040) > TWL6040_REV_ES1_0)
		twl6040->audpwron = pdata->audpwron_gpio;
	else
		twl6040->audpwron = -EINVAL;

	if (gpio_is_valid(twl6040->audpwron)) {
		ret = gpio_request_one(twl6040->audpwron, GPIOF_OUT_INIT_LOW,
				       "audpwron");
		if (ret)
			goto gpio1_err;
	}

	/* codec interrupt */
	ret = twl6040_irq_init(twl6040);
	if (ret)
		goto gpio2_err;

	ret = request_threaded_irq(twl6040->irq_base + TWL6040_IRQ_READY,
				   NULL, twl6040_naudint_handler, 0,
				   "twl6040_irq_ready", twl6040);
	if (ret) {
		dev_err(twl6040->dev, "READY IRQ request failed: %d\n",
			ret);
		goto irq_err;
	}

	/* dual-access registers controlled by I2C only */
	twl6040_set_bits(twl6040, TWL6040_REG_ACCCTL, TWL6040_I2CSEL);

	if (pdata->codec) {
		int irq = twl6040->irq_base + TWL6040_IRQ_PLUG;

		cell = &twl6040->cells[children];
		cell->name = "twl6040-codec";
		twl6040_codec_rsrc[0].start = irq;
		twl6040_codec_rsrc[0].end = irq;
		cell->resources = twl6040_codec_rsrc;
		cell->num_resources = ARRAY_SIZE(twl6040_codec_rsrc);
		cell->platform_data = pdata->codec;
		cell->pdata_size = sizeof(*pdata->codec);
		children++;
	}

	if (pdata->vibra) {
		int irq = twl6040->irq_base + TWL6040_IRQ_VIB;

		cell = &twl6040->cells[children];
		cell->name = "twl6040-vibra";
		twl6040_vibra_rsrc[0].start = irq;
		twl6040_vibra_rsrc[0].end = irq;
		cell->resources = twl6040_vibra_rsrc;
		cell->num_resources = ARRAY_SIZE(twl6040_vibra_rsrc);

		cell->platform_data = pdata->vibra;
		cell->pdata_size = sizeof(*pdata->vibra);
		children++;
	}

	if (children) {
		ret = mfd_add_devices(&client->dev, -1, twl6040->cells,
				      children, NULL, 0);
		if (ret)
			goto mfd_err;
	} else {
		dev_err(&client->dev, "No platform data found for children\n");
		ret = -ENODEV;
		goto mfd_err;
	}

	return 0;

mfd_err:
	free_irq(twl6040->irq_base + TWL6040_IRQ_READY, twl6040);
irq_err:
	twl6040_irq_exit(twl6040);
gpio2_err:
	if (gpio_is_valid(twl6040->audpwron))
		gpio_free(twl6040->audpwron);
gpio1_err:
	i2c_set_clientdata(client, NULL);
	regmap_exit(twl6040->regmap);
err:
	return ret;
}

static int __devexit twl6040_remove(struct i2c_client *client)
{
	struct twl6040 *twl6040 = i2c_get_clientdata(client);

	if (twl6040->power_count)
		twl6040_power(twl6040, 0);

	if (gpio_is_valid(twl6040->audpwron))
		gpio_free(twl6040->audpwron);

	free_irq(twl6040->irq_base + TWL6040_IRQ_READY, twl6040);
	twl6040_irq_exit(twl6040);

	mfd_remove_devices(&client->dev);
	i2c_set_clientdata(client, NULL);
	regmap_exit(twl6040->regmap);

	return 0;
}

static const struct i2c_device_id twl6040_i2c_id[] = {
	{ "twl6040", 0, },
	{ },
};
MODULE_DEVICE_TABLE(i2c, twl6040_i2c_id);

static struct i2c_driver twl6040_driver = {
	.driver = {
		.name = "twl6040",
		.owner = THIS_MODULE,
	},
	.probe		= twl6040_probe,
	.remove		= __devexit_p(twl6040_remove),
	.id_table	= twl6040_i2c_id,
};

module_i2c_driver(twl6040_driver);

MODULE_DESCRIPTION("TWL6040 MFD");
MODULE_AUTHOR("Misael Lopez Cruz <misael.lopez@ti.com>");
MODULE_AUTHOR("Jorge Eduardo Candelaria <jorge.candelaria@ti.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:twl6040");