summaryrefslogtreecommitdiffstats
path: root/drivers/mfd/wm8400-core.c
blob: c6fb5d16ca09590c04f5e1f032e104d791a92ee7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
/*
 * Core driver for WM8400.
 *
 * Copyright 2008 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/module.h>
#include <linux/bug.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/mfd/core.h>
#include <linux/mfd/wm8400-private.h>
#include <linux/mfd/wm8400-audio.h>
#include <linux/regmap.h>
#include <linux/slab.h>

static bool wm8400_volatile(struct device *dev, unsigned int reg)
{
	switch (reg) {
	case WM8400_INTERRUPT_STATUS_1:
	case WM8400_INTERRUPT_LEVELS:
	case WM8400_SHUTDOWN_REASON:
		return true;
	default:
		return false;
	}
}

/**
 * wm8400_reg_read - Single register read
 *
 * @wm8400: Pointer to wm8400 control structure
 * @reg:    Register to read
 *
 * @return  Read value
 */
u16 wm8400_reg_read(struct wm8400 *wm8400, u8 reg)
{
	unsigned int val;
	int ret;

	ret = regmap_read(wm8400->regmap, reg, &val);
	if (ret < 0)
		return ret;

	return val;
}
EXPORT_SYMBOL_GPL(wm8400_reg_read);

int wm8400_block_read(struct wm8400 *wm8400, u8 reg, int count, u16 *data)
{
	return regmap_bulk_read(wm8400->regmap, reg, data, count);
}
EXPORT_SYMBOL_GPL(wm8400_block_read);

static int wm8400_register_codec(struct wm8400 *wm8400)
{
	const struct mfd_cell cell = {
		.name = "wm8400-codec",
		.platform_data = wm8400,
		.pdata_size = sizeof(*wm8400),
	};

	return mfd_add_devices(wm8400->dev, -1, &cell, 1, NULL, 0, NULL);
}

/*
 * wm8400_init - Generic initialisation
 *
 * The WM8400 can be configured as either an I2C or SPI device.  Probe
 * functions for each bus set up the accessors then call into this to
 * set up the device itself.
 */
static int wm8400_init(struct wm8400 *wm8400,
		       struct wm8400_platform_data *pdata)
{
	unsigned int reg;
	int ret;

	dev_set_drvdata(wm8400->dev, wm8400);

	/* Check that this is actually a WM8400 */
	ret = regmap_read(wm8400->regmap, WM8400_RESET_ID, &reg);
	if (ret != 0) {
		dev_err(wm8400->dev, "Chip ID register read failed\n");
		return -EIO;
	}
	if (reg != 0x6172) {
		dev_err(wm8400->dev, "Device is not a WM8400, ID is %x\n",
			reg);
		return -ENODEV;
	}

	ret = regmap_read(wm8400->regmap, WM8400_ID, &reg);
	if (ret != 0) {
		dev_err(wm8400->dev, "ID register read failed: %d\n", ret);
		return ret;
	}
	reg = (reg & WM8400_CHIP_REV_MASK) >> WM8400_CHIP_REV_SHIFT;
	dev_info(wm8400->dev, "WM8400 revision %x\n", reg);

	ret = wm8400_register_codec(wm8400);
	if (ret != 0) {
		dev_err(wm8400->dev, "Failed to register codec\n");
		goto err_children;
	}

	if (pdata && pdata->platform_init) {
		ret = pdata->platform_init(wm8400->dev);
		if (ret != 0) {
			dev_err(wm8400->dev, "Platform init failed: %d\n",
				ret);
			goto err_children;
		}
	} else
		dev_warn(wm8400->dev, "No platform initialisation supplied\n");

	return 0;

err_children:
	mfd_remove_devices(wm8400->dev);
	return ret;
}

static void wm8400_release(struct wm8400 *wm8400)
{
	mfd_remove_devices(wm8400->dev);
}

static const struct regmap_config wm8400_regmap_config = {
	.reg_bits = 8,
	.val_bits = 16,
	.max_register = WM8400_REGISTER_COUNT - 1,

	.volatile_reg = wm8400_volatile,

	.cache_type = REGCACHE_RBTREE,
};

/**
 * wm8400_reset_codec_reg_cache - Reset cached codec registers to
 * their default values.
 */
void wm8400_reset_codec_reg_cache(struct wm8400 *wm8400)
{
	regmap_reinit_cache(wm8400->regmap, &wm8400_regmap_config);
}
EXPORT_SYMBOL_GPL(wm8400_reset_codec_reg_cache);

#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
static int wm8400_i2c_probe(struct i2c_client *i2c,
			    const struct i2c_device_id *id)
{
	struct wm8400 *wm8400;

	wm8400 = devm_kzalloc(&i2c->dev, sizeof(struct wm8400), GFP_KERNEL);
	if (!wm8400)
		return -ENOMEM;

	wm8400->regmap = devm_regmap_init_i2c(i2c, &wm8400_regmap_config);
	if (IS_ERR(wm8400->regmap))
		return PTR_ERR(wm8400->regmap);

	wm8400->dev = &i2c->dev;
	i2c_set_clientdata(i2c, wm8400);

	return wm8400_init(wm8400, dev_get_platdata(&i2c->dev));
}

static int wm8400_i2c_remove(struct i2c_client *i2c)
{
	struct wm8400 *wm8400 = i2c_get_clientdata(i2c);

	wm8400_release(wm8400);

	return 0;
}

static const struct i2c_device_id wm8400_i2c_id[] = {
       { "wm8400", 0 },
       { }
};
MODULE_DEVICE_TABLE(i2c, wm8400_i2c_id);

static struct i2c_driver wm8400_i2c_driver = {
	.driver = {
		.name = "WM8400",
		.owner = THIS_MODULE,
	},
	.probe    = wm8400_i2c_probe,
	.remove   = wm8400_i2c_remove,
	.id_table = wm8400_i2c_id,
};
#endif

static int __init wm8400_module_init(void)
{
	int ret = -ENODEV;

#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
	ret = i2c_add_driver(&wm8400_i2c_driver);
	if (ret != 0)
		pr_err("Failed to register I2C driver: %d\n", ret);
#endif

	return ret;
}
subsys_initcall(wm8400_module_init);

static void __exit wm8400_module_exit(void)
{
#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
	i2c_del_driver(&wm8400_i2c_driver);
#endif
}
module_exit(wm8400_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");