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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Core driver for WM8400.
4 *
5 * Copyright 2008 Wolfson Microelectronics PLC.
6 *
7 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
8 */
9
10#include <linux/init.h>
11#include <linux/bug.h>
12#include <linux/err.h>
13#include <linux/i2c.h>
14#include <linux/kernel.h>
15#include <linux/mfd/core.h>
16#include <linux/mfd/wm8400-private.h>
17#include <linux/mfd/wm8400-audio.h>
18#include <linux/regmap.h>
19#include <linux/slab.h>
20
21static bool wm8400_volatile(struct device *dev, unsigned int reg)
22{
23 switch (reg) {
24 case WM8400_INTERRUPT_STATUS_1:
25 case WM8400_INTERRUPT_LEVELS:
26 case WM8400_SHUTDOWN_REASON:
27 return true;
28 default:
29 return false;
30 }
31}
32
33static int wm8400_register_codec(struct wm8400 *wm8400)
34{
35 const struct mfd_cell cell = {
36 .name = "wm8400-codec",
37 .platform_data = wm8400,
38 .pdata_size = sizeof(*wm8400),
39 };
40
41 return devm_mfd_add_devices(wm8400->dev, -1, &cell, 1, NULL, 0, NULL);
42}
43
44/*
45 * wm8400_init - Generic initialisation
46 *
47 * The WM8400 can be configured as either an I2C or SPI device. Probe
48 * functions for each bus set up the accessors then call into this to
49 * set up the device itself.
50 */
51static int wm8400_init(struct wm8400 *wm8400,
52 struct wm8400_platform_data *pdata)
53{
54 unsigned int reg;
55 int ret;
56
57 dev_set_drvdata(wm8400->dev, wm8400);
58
59 /* Check that this is actually a WM8400 */
60 ret = regmap_read(wm8400->regmap, WM8400_RESET_ID, ®);
61 if (ret != 0) {
62 dev_err(wm8400->dev, "Chip ID register read failed\n");
63 return -EIO;
64 }
65 if (reg != 0x6172) {
66 dev_err(wm8400->dev, "Device is not a WM8400, ID is %x\n",
67 reg);
68 return -ENODEV;
69 }
70
71 ret = regmap_read(wm8400->regmap, WM8400_ID, ®);
72 if (ret != 0) {
73 dev_err(wm8400->dev, "ID register read failed: %d\n", ret);
74 return ret;
75 }
76 reg = (reg & WM8400_CHIP_REV_MASK) >> WM8400_CHIP_REV_SHIFT;
77 dev_info(wm8400->dev, "WM8400 revision %x\n", reg);
78
79 ret = wm8400_register_codec(wm8400);
80 if (ret != 0) {
81 dev_err(wm8400->dev, "Failed to register codec\n");
82 return ret;
83 }
84
85 if (pdata && pdata->platform_init) {
86 ret = pdata->platform_init(wm8400->dev);
87 if (ret != 0) {
88 dev_err(wm8400->dev, "Platform init failed: %d\n",
89 ret);
90 return ret;
91 }
92 } else
93 dev_warn(wm8400->dev, "No platform initialisation supplied\n");
94
95 return 0;
96}
97
98static const struct regmap_config wm8400_regmap_config = {
99 .reg_bits = 8,
100 .val_bits = 16,
101 .max_register = WM8400_REGISTER_COUNT - 1,
102
103 .volatile_reg = wm8400_volatile,
104
105 .cache_type = REGCACHE_RBTREE,
106};
107
108/**
109 * wm8400_reset_codec_reg_cache - Reset cached codec registers to
110 * their default values.
111 *
112 * @wm8400: pointer to local driver data structure
113 */
114void wm8400_reset_codec_reg_cache(struct wm8400 *wm8400)
115{
116 regmap_reinit_cache(wm8400->regmap, &wm8400_regmap_config);
117}
118EXPORT_SYMBOL_GPL(wm8400_reset_codec_reg_cache);
119
120#if IS_ENABLED(CONFIG_I2C)
121static int wm8400_i2c_probe(struct i2c_client *i2c,
122 const struct i2c_device_id *id)
123{
124 struct wm8400 *wm8400;
125
126 wm8400 = devm_kzalloc(&i2c->dev, sizeof(struct wm8400), GFP_KERNEL);
127 if (!wm8400)
128 return -ENOMEM;
129
130 wm8400->regmap = devm_regmap_init_i2c(i2c, &wm8400_regmap_config);
131 if (IS_ERR(wm8400->regmap))
132 return PTR_ERR(wm8400->regmap);
133
134 wm8400->dev = &i2c->dev;
135 i2c_set_clientdata(i2c, wm8400);
136
137 return wm8400_init(wm8400, dev_get_platdata(&i2c->dev));
138}
139
140static const struct i2c_device_id wm8400_i2c_id[] = {
141 { "wm8400", 0 },
142 { }
143};
144
145static struct i2c_driver wm8400_i2c_driver = {
146 .driver = {
147 .name = "WM8400",
148 },
149 .probe = wm8400_i2c_probe,
150 .id_table = wm8400_i2c_id,
151};
152#endif
153
154static int __init wm8400_driver_init(void)
155{
156 int ret = -ENODEV;
157
158#if IS_ENABLED(CONFIG_I2C)
159 ret = i2c_add_driver(&wm8400_i2c_driver);
160 if (ret != 0)
161 pr_err("Failed to register I2C driver: %d\n", ret);
162#endif
163
164 return ret;
165}
166subsys_initcall(wm8400_driver_init);
1/*
2 * Core driver for WM8400.
3 *
4 * Copyright 2008 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
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of the
11 * License, or (at your option) any later version.
12 *
13 */
14
15#include <linux/module.h>
16#include <linux/bug.h>
17#include <linux/err.h>
18#include <linux/i2c.h>
19#include <linux/kernel.h>
20#include <linux/mfd/core.h>
21#include <linux/mfd/wm8400-private.h>
22#include <linux/mfd/wm8400-audio.h>
23#include <linux/regmap.h>
24#include <linux/slab.h>
25
26static bool wm8400_volatile(struct device *dev, unsigned int reg)
27{
28 switch (reg) {
29 case WM8400_INTERRUPT_STATUS_1:
30 case WM8400_INTERRUPT_LEVELS:
31 case WM8400_SHUTDOWN_REASON:
32 return true;
33 default:
34 return false;
35 }
36}
37
38/**
39 * wm8400_reg_read - Single register read
40 *
41 * @wm8400: Pointer to wm8400 control structure
42 * @reg: Register to read
43 *
44 * @return Read value
45 */
46u16 wm8400_reg_read(struct wm8400 *wm8400, u8 reg)
47{
48 unsigned int val;
49 int ret;
50
51 ret = regmap_read(wm8400->regmap, reg, &val);
52 if (ret < 0)
53 return ret;
54
55 return val;
56}
57EXPORT_SYMBOL_GPL(wm8400_reg_read);
58
59int wm8400_block_read(struct wm8400 *wm8400, u8 reg, int count, u16 *data)
60{
61 return regmap_bulk_read(wm8400->regmap, reg, data, count);
62}
63EXPORT_SYMBOL_GPL(wm8400_block_read);
64
65static int wm8400_register_codec(struct wm8400 *wm8400)
66{
67 struct mfd_cell cell = {
68 .name = "wm8400-codec",
69 .platform_data = wm8400,
70 .pdata_size = sizeof(*wm8400),
71 };
72
73 return mfd_add_devices(wm8400->dev, -1, &cell, 1, NULL, 0);
74}
75
76/*
77 * wm8400_init - Generic initialisation
78 *
79 * The WM8400 can be configured as either an I2C or SPI device. Probe
80 * functions for each bus set up the accessors then call into this to
81 * set up the device itself.
82 */
83static int wm8400_init(struct wm8400 *wm8400,
84 struct wm8400_platform_data *pdata)
85{
86 unsigned int reg;
87 int ret;
88
89 dev_set_drvdata(wm8400->dev, wm8400);
90
91 /* Check that this is actually a WM8400 */
92 ret = regmap_read(wm8400->regmap, WM8400_RESET_ID, ®);
93 if (ret != 0) {
94 dev_err(wm8400->dev, "Chip ID register read failed\n");
95 return -EIO;
96 }
97 if (reg != 0x6172) {
98 dev_err(wm8400->dev, "Device is not a WM8400, ID is %x\n",
99 reg);
100 return -ENODEV;
101 }
102
103 ret = regmap_read(wm8400->regmap, WM8400_ID, ®);
104 if (ret != 0) {
105 dev_err(wm8400->dev, "ID register read failed: %d\n", ret);
106 return ret;
107 }
108 reg = (reg & WM8400_CHIP_REV_MASK) >> WM8400_CHIP_REV_SHIFT;
109 dev_info(wm8400->dev, "WM8400 revision %x\n", reg);
110
111 ret = wm8400_register_codec(wm8400);
112 if (ret != 0) {
113 dev_err(wm8400->dev, "Failed to register codec\n");
114 goto err_children;
115 }
116
117 if (pdata && pdata->platform_init) {
118 ret = pdata->platform_init(wm8400->dev);
119 if (ret != 0) {
120 dev_err(wm8400->dev, "Platform init failed: %d\n",
121 ret);
122 goto err_children;
123 }
124 } else
125 dev_warn(wm8400->dev, "No platform initialisation supplied\n");
126
127 return 0;
128
129err_children:
130 mfd_remove_devices(wm8400->dev);
131 return ret;
132}
133
134static void wm8400_release(struct wm8400 *wm8400)
135{
136 mfd_remove_devices(wm8400->dev);
137}
138
139static const struct regmap_config wm8400_regmap_config = {
140 .reg_bits = 8,
141 .val_bits = 16,
142 .max_register = WM8400_REGISTER_COUNT - 1,
143
144 .volatile_reg = wm8400_volatile,
145
146 .cache_type = REGCACHE_RBTREE,
147};
148
149/**
150 * wm8400_reset_codec_reg_cache - Reset cached codec registers to
151 * their default values.
152 */
153void wm8400_reset_codec_reg_cache(struct wm8400 *wm8400)
154{
155 regmap_reinit_cache(wm8400->regmap, &wm8400_regmap_config);
156}
157EXPORT_SYMBOL_GPL(wm8400_reset_codec_reg_cache);
158
159#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
160static int wm8400_i2c_probe(struct i2c_client *i2c,
161 const struct i2c_device_id *id)
162{
163 struct wm8400 *wm8400;
164 int ret;
165
166 wm8400 = devm_kzalloc(&i2c->dev, sizeof(struct wm8400), GFP_KERNEL);
167 if (wm8400 == NULL) {
168 ret = -ENOMEM;
169 goto err;
170 }
171
172 wm8400->regmap = devm_regmap_init_i2c(i2c, &wm8400_regmap_config);
173 if (IS_ERR(wm8400->regmap)) {
174 ret = PTR_ERR(wm8400->regmap);
175 goto err;
176 }
177
178 wm8400->dev = &i2c->dev;
179 i2c_set_clientdata(i2c, wm8400);
180
181 ret = wm8400_init(wm8400, i2c->dev.platform_data);
182 if (ret != 0)
183 goto err;
184
185 return 0;
186
187err:
188 return ret;
189}
190
191static int wm8400_i2c_remove(struct i2c_client *i2c)
192{
193 struct wm8400 *wm8400 = i2c_get_clientdata(i2c);
194
195 wm8400_release(wm8400);
196
197 return 0;
198}
199
200static const struct i2c_device_id wm8400_i2c_id[] = {
201 { "wm8400", 0 },
202 { }
203};
204MODULE_DEVICE_TABLE(i2c, wm8400_i2c_id);
205
206static struct i2c_driver wm8400_i2c_driver = {
207 .driver = {
208 .name = "WM8400",
209 .owner = THIS_MODULE,
210 },
211 .probe = wm8400_i2c_probe,
212 .remove = wm8400_i2c_remove,
213 .id_table = wm8400_i2c_id,
214};
215#endif
216
217static int __init wm8400_module_init(void)
218{
219 int ret = -ENODEV;
220
221#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
222 ret = i2c_add_driver(&wm8400_i2c_driver);
223 if (ret != 0)
224 pr_err("Failed to register I2C driver: %d\n", ret);
225#endif
226
227 return ret;
228}
229subsys_initcall(wm8400_module_init);
230
231static void __exit wm8400_module_exit(void)
232{
233#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
234 i2c_del_driver(&wm8400_i2c_driver);
235#endif
236}
237module_exit(wm8400_module_exit);
238
239MODULE_LICENSE("GPL");
240MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");