Home Home > GIT Browse
summaryrefslogtreecommitdiff
blob: 3055d6f47afcce12397857655748705611cedcfa (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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Core driver for WM8400.
 *
 * Copyright 2008 Wolfson Microelectronics PLC.
 *
 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
 */

#include <linux/init.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;
	}
}

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

	return devm_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");
		return ret;
	}

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

	return 0;
}

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 IS_ENABLED(CONFIG_I2C)
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 const struct i2c_device_id wm8400_i2c_id[] = {
       { "wm8400", 0 },
       { }
};

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

static int __init wm8400_driver_init(void)
{
	int ret = -ENODEV;

#if IS_ENABLED(CONFIG_I2C)
	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_driver_init);