[net-next-2.6.git] / drivers / mfd / wm8994-core.c

/*
 * wm8994-core.c  --  Device access for Wolfson WM8994
 *
 * Copyright 2009 Wolfson Microelectronics PLC.
 *
 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
 *
 *  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/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/mfd/core.h>
#include <linux/regulator/consumer.h>
#include <linux/regulator/machine.h>

#include <linux/mfd/wm8994/core.h>
#include <linux/mfd/wm8994/pdata.h>
#include <linux/mfd/wm8994/registers.h>

static int wm8994_read(struct wm8994 *wm8994, unsigned short reg,
		       int bytes, void *dest)
{
	int ret, i;
	u16 *buf = dest;

	BUG_ON(bytes % 2);
	BUG_ON(bytes <= 0);

	ret = wm8994->read_dev(wm8994, reg, bytes, dest);
	if (ret < 0)
		return ret;

	for (i = 0; i < bytes / 2; i++) {
		buf[i] = be16_to_cpu(buf[i]);

		dev_vdbg(wm8994->dev, "Read %04x from R%d(0x%x)\n",
			 buf[i], reg + i, reg + i);
	}

	return 0;
}

/**
 * wm8994_reg_read: Read a single WM8994 register.
 *
 * @wm8994: Device to read from.
 * @reg: Register to read.
 */
int wm8994_reg_read(struct wm8994 *wm8994, unsigned short reg)
{
	unsigned short val;
	int ret;

	mutex_lock(&wm8994->io_lock);

	ret = wm8994_read(wm8994, reg, 2, &val);

	mutex_unlock(&wm8994->io_lock);

	if (ret < 0)
		return ret;
	else
		return val;
}
EXPORT_SYMBOL_GPL(wm8994_reg_read);

/**
 * wm8994_bulk_read: Read multiple WM8994 registers
 *
 * @wm8994: Device to read from
 * @reg: First register
 * @count: Number of registers
 * @buf: Buffer to fill.
 */
int wm8994_bulk_read(struct wm8994 *wm8994, unsigned short reg,
		     int count, u16 *buf)
{
	int ret;

	mutex_lock(&wm8994->io_lock);

	ret = wm8994_read(wm8994, reg, count * 2, buf);

	mutex_unlock(&wm8994->io_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(wm8994_bulk_read);

static int wm8994_write(struct wm8994 *wm8994, unsigned short reg,
			int bytes, void *src)
{
	u16 *buf = src;
	int i;

	BUG_ON(bytes % 2);
	BUG_ON(bytes <= 0);

	for (i = 0; i < bytes / 2; i++) {
		dev_vdbg(wm8994->dev, "Write %04x to R%d(0x%x)\n",
			 buf[i], reg + i, reg + i);

		buf[i] = cpu_to_be16(buf[i]);
	}

	return wm8994->write_dev(wm8994, reg, bytes, src);
}

/**
 * wm8994_reg_write: Write a single WM8994 register.
 *
 * @wm8994: Device to write to.
 * @reg: Register to write to.
 * @val: Value to write.
 */
int wm8994_reg_write(struct wm8994 *wm8994, unsigned short reg,
		     unsigned short val)
{
	int ret;

	mutex_lock(&wm8994->io_lock);

	ret = wm8994_write(wm8994, reg, 2, &val);

	mutex_unlock(&wm8994->io_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(wm8994_reg_write);

/**
 * wm8994_set_bits: Set the value of a bitfield in a WM8994 register
 *
 * @wm8994: Device to write to.
 * @reg: Register to write to.
 * @mask: Mask of bits to set.
 * @val: Value to set (unshifted)
 */
int wm8994_set_bits(struct wm8994 *wm8994, unsigned short reg,
		    unsigned short mask, unsigned short val)
{
	int ret;
	u16 r;

	mutex_lock(&wm8994->io_lock);

	ret = wm8994_read(wm8994, reg, 2, &r);
	if (ret < 0)
		goto out;

	r &= ~mask;
	r |= val;

	ret = wm8994_write(wm8994, reg, 2, &r);

out:
	mutex_unlock(&wm8994->io_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(wm8994_set_bits);

static struct mfd_cell wm8994_regulator_devs[] = {
	{ .name = "wm8994-ldo", .id = 1 },
	{ .name = "wm8994-ldo", .id = 2 },
};

static struct resource wm8994_codec_resources[] = {
	{
		.start = WM8994_IRQ_TEMP_SHUT,
		.end   = WM8994_IRQ_TEMP_WARN,
		.flags = IORESOURCE_IRQ,
	},
};

static struct resource wm8994_gpio_resources[] = {
	{
		.start = WM8994_IRQ_GPIO(1),
		.end   = WM8994_IRQ_GPIO(11),
		.flags = IORESOURCE_IRQ,
	},
};

static struct mfd_cell wm8994_devs[] = {
	{
		.name = "wm8994-codec",
		.num_resources = ARRAY_SIZE(wm8994_codec_resources),
		.resources = wm8994_codec_resources,
	},

	{
		.name = "wm8994-gpio",
		.num_resources = ARRAY_SIZE(wm8994_gpio_resources),
		.resources = wm8994_gpio_resources,
	},
};

/*
 * Supplies for the main bulk of CODEC; the LDO supplies are ignored
 * and should be handled via the standard regulator API supply
 * management.
 */
static const char *wm8994_main_supplies[] = {
	"DBVDD",
	"DCVDD",
	"AVDD1",
	"AVDD2",
	"CPVDD",
	"SPKVDD1",
	"SPKVDD2",
};

#ifdef CONFIG_PM
static int wm8994_device_suspend(struct device *dev)
{
	struct wm8994 *wm8994 = dev_get_drvdata(dev);
	int ret;

	/* GPIO configuration state is saved here since we may be configuring
	 * the GPIO alternate functions even if we're not using the gpiolib
	 * driver for them.
	 */
	ret = wm8994_read(wm8994, WM8994_GPIO_1, WM8994_NUM_GPIO_REGS * 2,
			  &wm8994->gpio_regs);
	if (ret < 0)
		dev_err(dev, "Failed to save GPIO registers: %d\n", ret);

	/* For similar reasons we also stash the regulator states */
	ret = wm8994_read(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
			  &wm8994->ldo_regs);
	if (ret < 0)
		dev_err(dev, "Failed to save LDO registers: %d\n", ret);

	ret = regulator_bulk_disable(ARRAY_SIZE(wm8994_main_supplies),
				     wm8994->supplies);
	if (ret != 0) {
		dev_err(dev, "Failed to disable supplies: %d\n", ret);
		return ret;
	}

	return 0;
}

static int wm8994_device_resume(struct device *dev)
{
	struct wm8994 *wm8994 = dev_get_drvdata(dev);
	int ret;

	ret = regulator_bulk_enable(ARRAY_SIZE(wm8994_main_supplies),
				    wm8994->supplies);
	if (ret != 0) {
		dev_err(dev, "Failed to enable supplies: %d\n", ret);
		return ret;
	}

	ret = wm8994_write(wm8994, WM8994_INTERRUPT_STATUS_1_MASK,
			   WM8994_NUM_IRQ_REGS * 2, &wm8994->irq_masks_cur);
	if (ret < 0)
		dev_err(dev, "Failed to restore interrupt masks: %d\n", ret);

	ret = wm8994_write(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
			   &wm8994->ldo_regs);
	if (ret < 0)
		dev_err(dev, "Failed to restore LDO registers: %d\n", ret);

	ret = wm8994_write(wm8994, WM8994_GPIO_1, WM8994_NUM_GPIO_REGS * 2,
			   &wm8994->gpio_regs);
	if (ret < 0)
		dev_err(dev, "Failed to restore GPIO registers: %d\n", ret);

	return 0;
}
#endif

#ifdef CONFIG_REGULATOR
static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
{
	struct wm8994_ldo_pdata *ldo_pdata;

	if (!pdata)
		return 0;

	ldo_pdata = &pdata->ldo[ldo];

	if (!ldo_pdata->init_data)
		return 0;

	return ldo_pdata->init_data->num_consumer_supplies != 0;
}
#else
static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
{
	return 0;
}
#endif

/*
 * Instantiate the generic non-control parts of the device.
 */
static int wm8994_device_init(struct wm8994 *wm8994, unsigned long id, int irq)
{
	struct wm8994_pdata *pdata = wm8994->dev->platform_data;
	int ret, i;

	mutex_init(&wm8994->io_lock);
	dev_set_drvdata(wm8994->dev, wm8994);

	/* Add the on-chip regulators first for bootstrapping */
	ret = mfd_add_devices(wm8994->dev, -1,
			      wm8994_regulator_devs,
			      ARRAY_SIZE(wm8994_regulator_devs),
			      NULL, 0);
	if (ret != 0) {
		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
		goto err;
	}

	wm8994->supplies = kzalloc(sizeof(struct regulator_bulk_data) *
				   ARRAY_SIZE(wm8994_main_supplies),
				   GFP_KERNEL);
	if (!wm8994->supplies)
		goto err;

	for (i = 0; i < ARRAY_SIZE(wm8994_main_supplies); i++)
		wm8994->supplies[i].supply = wm8994_main_supplies[i];

	ret = regulator_bulk_get(wm8994->dev, ARRAY_SIZE(wm8994_main_supplies),
				 wm8994->supplies);
	if (ret != 0) {
		dev_err(wm8994->dev, "Failed to get supplies: %d\n", ret);
		goto err_supplies;
	}

	ret = regulator_bulk_enable(ARRAY_SIZE(wm8994_main_supplies),
				    wm8994->supplies);
	if (ret != 0) {
		dev_err(wm8994->dev, "Failed to enable supplies: %d\n", ret);
		goto err_get;
	}

	ret = wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET);
	if (ret < 0) {
		dev_err(wm8994->dev, "Failed to read ID register\n");
		goto err_enable;
	}
	if (ret != 0x8994) {
		dev_err(wm8994->dev, "Device is not a WM8994, ID is %x\n",
			ret);
		ret = -EINVAL;
		goto err_enable;
	}

	ret = wm8994_reg_read(wm8994, WM8994_CHIP_REVISION);
	if (ret < 0) {
		dev_err(wm8994->dev, "Failed to read revision register: %d\n",
			ret);
		goto err_enable;
	}

	switch (ret) {
	case 0:
	case 1:
		dev_warn(wm8994->dev, "revision %c not fully supported\n",
			'A' + ret);
		break;
	default:
		dev_info(wm8994->dev, "revision %c\n", 'A' + ret);
		break;
	}


	if (pdata) {
		wm8994->irq_base = pdata->irq_base;
		wm8994->gpio_base = pdata->gpio_base;

		/* GPIO configuration is only applied if it's non-zero */
		for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) {
			if (pdata->gpio_defaults[i]) {
				wm8994_set_bits(wm8994, WM8994_GPIO_1 + i,
						0xffff,
						pdata->gpio_defaults[i]);
			}
		}
	}

	/* In some system designs where the regulators are not in use,
	 * we can achieve a small reduction in leakage currents by
	 * floating LDO outputs.  This bit makes no difference if the
	 * LDOs are enabled, it only affects cases where the LDOs were
	 * in operation and are then disabled.
	 */
	for (i = 0; i < WM8994_NUM_LDO_REGS; i++) {
		if (wm8994_ldo_in_use(pdata, i))
			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
					WM8994_LDO1_DISCH, WM8994_LDO1_DISCH);
		else
			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
					WM8994_LDO1_DISCH, 0);
	}

	wm8994_irq_init(wm8994);

	ret = mfd_add_devices(wm8994->dev, -1,
			      wm8994_devs, ARRAY_SIZE(wm8994_devs),
			      NULL, 0);
	if (ret != 0) {
		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
		goto err_irq;
	}

	return 0;

err_irq:
	wm8994_irq_exit(wm8994);
err_enable:
	regulator_bulk_disable(ARRAY_SIZE(wm8994_main_supplies),
			       wm8994->supplies);
err_get:
	regulator_bulk_free(ARRAY_SIZE(wm8994_main_supplies), wm8994->supplies);
err_supplies:
	kfree(wm8994->supplies);
err:
	mfd_remove_devices(wm8994->dev);
	kfree(wm8994);
	return ret;
}

static void wm8994_device_exit(struct wm8994 *wm8994)
{
	mfd_remove_devices(wm8994->dev);
	wm8994_irq_exit(wm8994);
	regulator_bulk_disable(ARRAY_SIZE(wm8994_main_supplies),
			       wm8994->supplies);
	regulator_bulk_free(ARRAY_SIZE(wm8994_main_supplies), wm8994->supplies);
	kfree(wm8994->supplies);
	kfree(wm8994);
}

static int wm8994_i2c_read_device(struct wm8994 *wm8994, unsigned short reg,
				  int bytes, void *dest)
{
	struct i2c_client *i2c = wm8994->control_data;
	int ret;
	u16 r = cpu_to_be16(reg);

	ret = i2c_master_send(i2c, (unsigned char *)&r, 2);
	if (ret < 0)
		return ret;
	if (ret != 2)
		return -EIO;

	ret = i2c_master_recv(i2c, dest, bytes);
	if (ret < 0)
		return ret;
	if (ret != bytes)
		return -EIO;
	return 0;
}

/* Currently we allocate the write buffer on the stack; this is OK for
 * small writes - if we need to do large writes this will need to be
 * revised.
 */
static int wm8994_i2c_write_device(struct wm8994 *wm8994, unsigned short reg,
				   int bytes, void *src)
{
	struct i2c_client *i2c = wm8994->control_data;
	unsigned char msg[bytes + 2];
	int ret;

	reg = cpu_to_be16(reg);
	memcpy(&msg[0], &reg, 2);
	memcpy(&msg[2], src, bytes);

	ret = i2c_master_send(i2c, msg, bytes + 2);
	if (ret < 0)
		return ret;
	if (ret < bytes + 2)
		return -EIO;

	return 0;
}

static int wm8994_i2c_probe(struct i2c_client *i2c,
			    const struct i2c_device_id *id)
{
	struct wm8994 *wm8994;

	wm8994 = kzalloc(sizeof(struct wm8994), GFP_KERNEL);
	if (wm8994 == NULL) {
		kfree(i2c);
		return -ENOMEM;
	}

	i2c_set_clientdata(i2c, wm8994);
	wm8994->dev = &i2c->dev;
	wm8994->control_data = i2c;
	wm8994->read_dev = wm8994_i2c_read_device;
	wm8994->write_dev = wm8994_i2c_write_device;
	wm8994->irq = i2c->irq;

	return wm8994_device_init(wm8994, id->driver_data, i2c->irq);
}

static int wm8994_i2c_remove(struct i2c_client *i2c)
{
	struct wm8994 *wm8994 = i2c_get_clientdata(i2c);

	wm8994_device_exit(wm8994);

	return 0;
}

#ifdef CONFIG_PM
static int wm8994_i2c_suspend(struct i2c_client *i2c, pm_message_t state)
{
	return wm8994_device_suspend(&i2c->dev);
}

static int wm8994_i2c_resume(struct i2c_client *i2c)
{
	return wm8994_device_resume(&i2c->dev);
}
#else
#define wm8994_i2c_suspend NULL
#define wm8994_i2c_resume NULL
#endif

static const struct i2c_device_id wm8994_i2c_id[] = {
	{ "wm8994", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, wm8994_i2c_id);

static struct i2c_driver wm8994_i2c_driver = {
	.driver = {
		   .name = "wm8994",
		   .owner = THIS_MODULE,
	},
	.probe = wm8994_i2c_probe,
	.remove = wm8994_i2c_remove,
	.suspend = wm8994_i2c_suspend,
	.resume = wm8994_i2c_resume,
	.id_table = wm8994_i2c_id,
};

static int __init wm8994_i2c_init(void)
{
	int ret;

	ret = i2c_add_driver(&wm8994_i2c_driver);
	if (ret != 0)
		pr_err("Failed to register wm8994 I2C driver: %d\n", ret);

	return ret;
}
module_init(wm8994_i2c_init);

static void __exit wm8994_i2c_exit(void)
{
	i2c_del_driver(&wm8994_i2c_driver);
}
module_exit(wm8994_i2c_exit);

MODULE_DESCRIPTION("Core support for the WM8994 audio CODEC");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
Commit	Line	Data
9e501086 MB	1	/*
	2	* wm8994-core.c -- Device access for Wolfson WM8994
	3	*
	4	* Copyright 2009 Wolfson Microelectronics PLC.
	5	*
	6	* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify it
	9	* under the terms of the GNU General Public License as published by the
	10	* Free Software Foundation; either version 2 of the License, or (at your
	11	* option) any later version.
	12	*
	13	*/
	14
	15	#include <linux/kernel.h>
	16	#include <linux/module.h>
5a0e3ad6	17	#include <linux/slab.h>
9e501086 MB	18	#include <linux/i2c.h>
	19	#include <linux/delay.h>
	20	#include <linux/mfd/core.h>
	21	#include <linux/regulator/consumer.h>
	22	#include <linux/regulator/machine.h>
	23
	24	#include <linux/mfd/wm8994/core.h>
	25	#include <linux/mfd/wm8994/pdata.h>
	26	#include <linux/mfd/wm8994/registers.h>
	27
	28	static int wm8994_read(struct wm8994 *wm8994, unsigned short reg,
	29	int bytes, void *dest)
	30	{
	31	int ret, i;
	32	u16 *buf = dest;
	33
	34	BUG_ON(bytes % 2);
	35	BUG_ON(bytes <= 0);
	36
	37	ret = wm8994->read_dev(wm8994, reg, bytes, dest);
	38	if (ret < 0)
	39	return ret;
	40
	41	for (i = 0; i < bytes / 2; i++) {
	42	buf[i] = be16_to_cpu(buf[i]);
	43
	44	dev_vdbg(wm8994->dev, "Read %04x from R%d(0x%x)\n",
	45	buf[i], reg + i, reg + i);
	46	}
	47
	48	return 0;
	49	}
	50
	51	/**
	52	* wm8994_reg_read: Read a single WM8994 register.
	53	*
	54	* @wm8994: Device to read from.
	55	* @reg: Register to read.
	56	*/
	57	int wm8994_reg_read(struct wm8994 *wm8994, unsigned short reg)
	58	{
	59	unsigned short val;
	60	int ret;
	61
	62	mutex_lock(&wm8994->io_lock);
	63
	64	ret = wm8994_read(wm8994, reg, 2, &val);
	65
	66	mutex_unlock(&wm8994->io_lock);
	67
	68	if (ret < 0)
	69	return ret;
	70	else
	71	return val;
	72	}
	73	EXPORT_SYMBOL_GPL(wm8994_reg_read);
	74
	75	/**
	76	* wm8994_bulk_read: Read multiple WM8994 registers
	77	*
	78	* @wm8994: Device to read from
	79	* @reg: First register
	80	* @count: Number of registers
	81	* @buf: Buffer to fill.
82	*/
83	int wm8994_bulk_read(struct wm8994 *wm8994, unsigned short reg,
84	int count, u16 *buf)
85	{
86	int ret;
87
88	mutex_lock(&wm8994->io_lock);
89
90	ret = wm8994_read(wm8994, reg, count * 2, buf);
91
92	mutex_unlock(&wm8994->io_lock);
93
94	return ret;
95	}
96	EXPORT_SYMBOL_GPL(wm8994_bulk_read);
97
98	static int wm8994_write(struct wm8994 *wm8994, unsigned short reg,
99	int bytes, void *src)
100	{
101	u16 *buf = src;
102	int i;
103
104	BUG_ON(bytes % 2);
105	BUG_ON(bytes <= 0);
106
107	for (i = 0; i < bytes / 2; i++) {
108	dev_vdbg(wm8994->dev, "Write %04x to R%d(0x%x)\n",
109	buf[i], reg + i, reg + i);
110
111	buf[i] = cpu_to_be16(buf[i]);
112	}
113
114	return wm8994->write_dev(wm8994, reg, bytes, src);
115	}
116
117	/**
118	* wm8994_reg_write: Write a single WM8994 register.
119	*
120	* @wm8994: Device to write to.
121	* @reg: Register to write to.
122	* @val: Value to write.
123	*/
124	int wm8994_reg_write(struct wm8994 *wm8994, unsigned short reg,
125	unsigned short val)
126	{
127	int ret;
128
129	mutex_lock(&wm8994->io_lock);
130
131	ret = wm8994_write(wm8994, reg, 2, &val);
132
133	mutex_unlock(&wm8994->io_lock);
134
135	return ret;
136	}
137	EXPORT_SYMBOL_GPL(wm8994_reg_write);
138
139	/**
140	* wm8994_set_bits: Set the value of a bitfield in a WM8994 register
141	*
142	* @wm8994: Device to write to.
143	* @reg: Register to write to.
144	* @mask: Mask of bits to set.
145	* @val: Value to set (unshifted)
146	*/
147	int wm8994_set_bits(struct wm8994 *wm8994, unsigned short reg,
148	unsigned short mask, unsigned short val)
149	{
150	int ret;
151	u16 r;
152
153	mutex_lock(&wm8994->io_lock);
154
155	ret = wm8994_read(wm8994, reg, 2, &r);
156	if (ret < 0)
157	goto out;
158
159	r &= ~mask;
160	r \|= val;
161
162	ret = wm8994_write(wm8994, reg, 2, &r);
163
164	out:
165	mutex_unlock(&wm8994->io_lock);
166
167	return ret;
168	}
169	EXPORT_SYMBOL_GPL(wm8994_set_bits);
170
171	static struct mfd_cell wm8994_regulator_devs[] = {
172	{ .name = "wm8994-ldo", .id = 1 },
173	{ .name = "wm8994-ldo", .id = 2 },
174	};
175
c9fbf7e0 MB	176	static struct resource wm8994_codec_resources[] = {
	177	{
	178	.start = WM8994_IRQ_TEMP_SHUT,
	179	.end = WM8994_IRQ_TEMP_WARN,
	180	.flags = IORESOURCE_IRQ,
	181	},
	182	};
	183
	184	static struct resource wm8994_gpio_resources[] = {
	185	{
	186	.start = WM8994_IRQ_GPIO(1),
	187	.end = WM8994_IRQ_GPIO(11),
	188	.flags = IORESOURCE_IRQ,
	189	},
	190	};
	191
9e501086	192	static struct mfd_cell wm8994_devs[] = {
c9fbf7e0 MB	193	{
	194	.name = "wm8994-codec",
	195	.num_resources = ARRAY_SIZE(wm8994_codec_resources),
	196	.resources = wm8994_codec_resources,
	197	},
	198
	199	{
	200	.name = "wm8994-gpio",
	201	.num_resources = ARRAY_SIZE(wm8994_gpio_resources),
	202	.resources = wm8994_gpio_resources,
	203	},
9e501086 MB	204	};
	205
	206	/*
	207	* Supplies for the main bulk of CODEC; the LDO supplies are ignored
	208	* and should be handled via the standard regulator API supply
	209	* management.
	210	*/
	211	static const char *wm8994_main_supplies[] = {
	212	"DBVDD",
	213	"DCVDD",
	214	"AVDD1",
	215	"AVDD2",
	216	"CPVDD",
	217	"SPKVDD1",
	218	"SPKVDD2",
	219	};
	220
	221	#ifdef CONFIG_PM
	222	static int wm8994_device_suspend(struct device *dev)
	223	{
	224	struct wm8994 *wm8994 = dev_get_drvdata(dev);
	225	int ret;
	226
	227	/* GPIO configuration state is saved here since we may be configuring
	228	* the GPIO alternate functions even if we're not using the gpiolib
	229	* driver for them.
	230	*/
	231	ret = wm8994_read(wm8994, WM8994_GPIO_1, WM8994_NUM_GPIO_REGS * 2,
	232	&wm8994->gpio_regs);
	233	if (ret < 0)
	234	dev_err(dev, "Failed to save GPIO registers: %d\n", ret);
	235
	236	/* For similar reasons we also stash the regulator states */
	237	ret = wm8994_read(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
	238	&wm8994->ldo_regs);
	239	if (ret < 0)
	240	dev_err(dev, "Failed to save LDO registers: %d\n", ret);
	241
	242	ret = regulator_bulk_disable(ARRAY_SIZE(wm8994_main_supplies),
	243	wm8994->supplies);
	244	if (ret != 0) {
	245	dev_err(dev, "Failed to disable supplies: %d\n", ret);
	246	return ret;
	247	}
	248
	249	return 0;
	250	}
	251
	252	static int wm8994_device_resume(struct device *dev)
	253	{
	254	struct wm8994 *wm8994 = dev_get_drvdata(dev);
	255	int ret;
	256
	257	ret = regulator_bulk_enable(ARRAY_SIZE(wm8994_main_supplies),
	258	wm8994->supplies);
	259	if (ret != 0) {
	260	dev_err(dev, "Failed to enable supplies: %d\n", ret);
	261	return ret;
	262	}
	263
c9fbf7e0 MB	264	ret = wm8994_write(wm8994, WM8994_INTERRUPT_STATUS_1_MASK,
	265	WM8994_NUM_IRQ_REGS * 2, &wm8994->irq_masks_cur);
	266	if (ret < 0)
	267	dev_err(dev, "Failed to restore interrupt masks: %d\n", ret);
	268
9e501086 MB	269	ret = wm8994_write(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
	270	&wm8994->ldo_regs);
	271	if (ret < 0)
	272	dev_err(dev, "Failed to restore LDO registers: %d\n", ret);
	273
	274	ret = wm8994_write(wm8994, WM8994_GPIO_1, WM8994_NUM_GPIO_REGS * 2,
	275	&wm8994->gpio_regs);
	276	if (ret < 0)
	277	dev_err(dev, "Failed to restore GPIO registers: %d\n", ret);
	278
	279	return 0;
	280	}
	281	#endif
	282
	283	#ifdef CONFIG_REGULATOR
	284	static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
	285	{
	286	struct wm8994_ldo_pdata *ldo_pdata;
	287
	288	if (!pdata)
	289	return 0;
	290
	291	ldo_pdata = &pdata->ldo[ldo];
	292
	293	if (!ldo_pdata->init_data)
	294	return 0;
	295
	296	return ldo_pdata->init_data->num_consumer_supplies != 0;
	297	}
	298	#else
	299	static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
	300	{
	301	return 0;
	302	}
	303	#endif
	304
	305	/*
	306	* Instantiate the generic non-control parts of the device.
	307	*/
	308	static int wm8994_device_init(struct wm8994 *wm8994, unsigned long id, int irq)
	309	{
	310	struct wm8994_pdata *pdata = wm8994->dev->platform_data;
	311	int ret, i;
	312
	313	mutex_init(&wm8994->io_lock);
	314	dev_set_drvdata(wm8994->dev, wm8994);
	315
	316	/* Add the on-chip regulators first for bootstrapping */
	317	ret = mfd_add_devices(wm8994->dev, -1,
	318	wm8994_regulator_devs,
	319	ARRAY_SIZE(wm8994_regulator_devs),
	320	NULL, 0);
	321	if (ret != 0) {
	322	dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
	323	goto err;
	324	}
	325
	326	wm8994->supplies = kzalloc(sizeof(struct regulator_bulk_data) *
	327	ARRAY_SIZE(wm8994_main_supplies),
	328	GFP_KERNEL);
	329	if (!wm8994->supplies)
	330	goto err;
	331
	332	for (i = 0; i < ARRAY_SIZE(wm8994_main_supplies); i++)
333	wm8994->supplies[i].supply = wm8994_main_supplies[i];
334
335	ret = regulator_bulk_get(wm8994->dev, ARRAY_SIZE(wm8994_main_supplies),
336	wm8994->supplies);
337	if (ret != 0) {
338	dev_err(wm8994->dev, "Failed to get supplies: %d\n", ret);
7731074a	339	goto err_supplies;
9e501086 MB	340	}
	341
	342	ret = regulator_bulk_enable(ARRAY_SIZE(wm8994_main_supplies),
	343	wm8994->supplies);
	344	if (ret != 0) {
	345	dev_err(wm8994->dev, "Failed to enable supplies: %d\n", ret);
7731074a	346	goto err_get;
9e501086 MB	347	}
	348
	349	ret = wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET);
	350	if (ret < 0) {
	351	dev_err(wm8994->dev, "Failed to read ID register\n");
	352	goto err_enable;
	353	}
	354	if (ret != 0x8994) {
	355	dev_err(wm8994->dev, "Device is not a WM8994, ID is %x\n",
	356	ret);
	357	ret = -EINVAL;
	358	goto err_enable;
	359	}
	360
	361	ret = wm8994_reg_read(wm8994, WM8994_CHIP_REVISION);
	362	if (ret < 0) {
	363	dev_err(wm8994->dev, "Failed to read revision register: %d\n",
	364	ret);
	365	goto err_enable;
	366	}
	367
	368	switch (ret) {
	369	case 0:
	370	case 1:
	371	dev_warn(wm8994->dev, "revision %c not fully supported\n",
	372	'A' + ret);
	373	break;
	374	default:
	375	dev_info(wm8994->dev, "revision %c\n", 'A' + ret);
	376	break;
	377	}
	378
	379
	380	if (pdata) {
c9fbf7e0	381	wm8994->irq_base = pdata->irq_base;
9e501086 MB	382	wm8994->gpio_base = pdata->gpio_base;
	383
	384	/* GPIO configuration is only applied if it's non-zero */
	385	for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) {
	386	if (pdata->gpio_defaults[i]) {
	387	wm8994_set_bits(wm8994, WM8994_GPIO_1 + i,
	388	0xffff,
	389	pdata->gpio_defaults[i]);
	390	}
	391	}
	392	}
	393
	394	/* In some system designs where the regulators are not in use,
	395	* we can achieve a small reduction in leakage currents by
	396	* floating LDO outputs. This bit makes no difference if the
	397	* LDOs are enabled, it only affects cases where the LDOs were
	398	* in operation and are then disabled.
	399	*/
	400	for (i = 0; i < WM8994_NUM_LDO_REGS; i++) {
	401	if (wm8994_ldo_in_use(pdata, i))
	402	wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
	403	WM8994_LDO1_DISCH, WM8994_LDO1_DISCH);
	404	else
	405	wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
	406	WM8994_LDO1_DISCH, 0);
	407	}
	408
c9fbf7e0 MB	409	wm8994_irq_init(wm8994);
c9fbf7e0 MB	410
9e501086 MB	411	ret = mfd_add_devices(wm8994->dev, -1,
	412	wm8994_devs, ARRAY_SIZE(wm8994_devs),
	413	NULL, 0);
	414	if (ret != 0) {
	415	dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
c9fbf7e0	416	goto err_irq;
9e501086 MB	417	}
	418
	419	return 0;
	420
c9fbf7e0 MB	421	err_irq:
c9fbf7e0 MB	422	wm8994_irq_exit(wm8994);
9e501086 MB	423	err_enable:
	424	regulator_bulk_disable(ARRAY_SIZE(wm8994_main_supplies),
	425	wm8994->supplies);
	426	err_get:
	427	regulator_bulk_free(ARRAY_SIZE(wm8994_main_supplies), wm8994->supplies);
	428	err_supplies:
	429	kfree(wm8994->supplies);
	430	err:
	431	mfd_remove_devices(wm8994->dev);
	432	kfree(wm8994);
	433	return ret;
	434	}
	435
	436	static void wm8994_device_exit(struct wm8994 *wm8994)
	437	{
	438	mfd_remove_devices(wm8994->dev);
c9fbf7e0	439	wm8994_irq_exit(wm8994);
9e501086 MB	440	regulator_bulk_disable(ARRAY_SIZE(wm8994_main_supplies),
	441	wm8994->supplies);
	442	regulator_bulk_free(ARRAY_SIZE(wm8994_main_supplies), wm8994->supplies);
	443	kfree(wm8994->supplies);
	444	kfree(wm8994);
	445	}
	446
	447	static int wm8994_i2c_read_device(struct wm8994 *wm8994, unsigned short reg,
	448	int bytes, void *dest)
	449	{
	450	struct i2c_client *i2c = wm8994->control_data;
	451	int ret;
	452	u16 r = cpu_to_be16(reg);
	453
	454	ret = i2c_master_send(i2c, (unsigned char *)&r, 2);
	455	if (ret < 0)
	456	return ret;
	457	if (ret != 2)
	458	return -EIO;
	459
	460	ret = i2c_master_recv(i2c, dest, bytes);
	461	if (ret < 0)
	462	return ret;
	463	if (ret != bytes)
	464	return -EIO;
	465	return 0;
	466	}
	467
	468	/* Currently we allocate the write buffer on the stack; this is OK for
	469	* small writes - if we need to do large writes this will need to be
	470	* revised.
	471	*/
	472	static int wm8994_i2c_write_device(struct wm8994 *wm8994, unsigned short reg,
	473	int bytes, void *src)
	474	{
	475	struct i2c_client *i2c = wm8994->control_data;
	476	unsigned char msg[bytes + 2];
	477	int ret;
	478
	479	reg = cpu_to_be16(reg);
	480	memcpy(&msg[0], &reg, 2);
	481	memcpy(&msg[2], src, bytes);
	482
	483	ret = i2c_master_send(i2c, msg, bytes + 2);
	484	if (ret < 0)
	485	return ret;
	486	if (ret < bytes + 2)
	487	return -EIO;
	488
	489	return 0;
	490	}
	491
	492	static int wm8994_i2c_probe(struct i2c_client *i2c,
	493	const struct i2c_device_id *id)
	494	{
	495	struct wm8994 *wm8994;
	496
	497	wm8994 = kzalloc(sizeof(struct wm8994), GFP_KERNEL);
	498	if (wm8994 == NULL) {
	499	kfree(i2c);
	500	return -ENOMEM;
	501	}
	502
	503	i2c_set_clientdata(i2c, wm8994);
504	wm8994->dev = &i2c->dev;
505	wm8994->control_data = i2c;
506	wm8994->read_dev = wm8994_i2c_read_device;
507	wm8994->write_dev = wm8994_i2c_write_device;
c9fbf7e0	508	wm8994->irq = i2c->irq;
9e501086 MB	509
	510	return wm8994_device_init(wm8994, id->driver_data, i2c->irq);
	511	}
	512
	513	static int wm8994_i2c_remove(struct i2c_client *i2c)
	514	{
	515	struct wm8994 *wm8994 = i2c_get_clientdata(i2c);
	516
	517	wm8994_device_exit(wm8994);
	518
	519	return 0;
	520	}
	521
	522	#ifdef CONFIG_PM
	523	static int wm8994_i2c_suspend(struct i2c_client *i2c, pm_message_t state)
	524	{
	525	return wm8994_device_suspend(&i2c->dev);
	526	}
	527
	528	static int wm8994_i2c_resume(struct i2c_client *i2c)
	529	{
	530	return wm8994_device_resume(&i2c->dev);
	531	}
	532	#else
	533	#define wm8994_i2c_suspend NULL
	534	#define wm8994_i2c_resume NULL
	535	#endif
	536
	537	static const struct i2c_device_id wm8994_i2c_id[] = {
	538	{ "wm8994", 0 },
	539	{ }
	540	};
	541	MODULE_DEVICE_TABLE(i2c, wm8994_i2c_id);
	542
	543	static struct i2c_driver wm8994_i2c_driver = {
	544	.driver = {
	545	.name = "wm8994",
	546	.owner = THIS_MODULE,
	547	},
	548	.probe = wm8994_i2c_probe,
	549	.remove = wm8994_i2c_remove,
	550	.suspend = wm8994_i2c_suspend,
	551	.resume = wm8994_i2c_resume,
	552	.id_table = wm8994_i2c_id,
	553	};
	554
	555	static int __init wm8994_i2c_init(void)
	556	{
	557	int ret;
	558
	559	ret = i2c_add_driver(&wm8994_i2c_driver);
	560	if (ret != 0)
	561	pr_err("Failed to register wm8994 I2C driver: %d\n", ret);
	562
	563	return ret;
	564	}
	565	module_init(wm8994_i2c_init);
	566
	567	static void __exit wm8994_i2c_exit(void)
	568	{
	569	i2c_del_driver(&wm8994_i2c_driver);
	570	}
	571	module_exit(wm8994_i2c_exit);
	572
573	MODULE_DESCRIPTION("Core support for the WM8994 audio CODEC");
574	MODULE_LICENSE("GPL");
575	MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");