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	/* Check that this is actually a WM8400 */
 58	ret = regmap_read(wm8400->regmap, WM8400_RESET_ID, &reg);
 59	if (ret != 0) {
 60		dev_err(wm8400->dev, "Chip ID register read failed\n");
 61		return -EIO;
 62	}
 63	if (reg != 0x6172) {
 64		dev_err(wm8400->dev, "Device is not a WM8400, ID is %x\n",
 65			reg);
 66		return -ENODEV;
 67	}
 68
 69	ret = regmap_read(wm8400->regmap, WM8400_ID, &reg);
 70	if (ret != 0) {
 71		dev_err(wm8400->dev, "ID register read failed: %d\n", ret);
 72		return ret;
 73	}
 74	reg = (reg & WM8400_CHIP_REV_MASK) >> WM8400_CHIP_REV_SHIFT;
 75	dev_info(wm8400->dev, "WM8400 revision %x\n", reg);
 76
 77	ret = wm8400_register_codec(wm8400);
 78	if (ret != 0) {
 79		dev_err(wm8400->dev, "Failed to register codec\n");
 80		return ret;
 81	}
 82
 83	if (pdata && pdata->platform_init) {
 84		ret = pdata->platform_init(wm8400->dev);
 85		if (ret != 0) {
 86			dev_err(wm8400->dev, "Platform init failed: %d\n",
 87				ret);
 88			return ret;
 89		}
 90	} else
 91		dev_warn(wm8400->dev, "No platform initialisation supplied\n");
 92
 93	return 0;
 94}
 95
 96static const struct regmap_config wm8400_regmap_config = {
 97	.reg_bits = 8,
 98	.val_bits = 16,
 99	.max_register = WM8400_REGISTER_COUNT - 1,
100
101	.volatile_reg = wm8400_volatile,
102
103	.cache_type = REGCACHE_RBTREE,
104};
105
106/**
107 * wm8400_reset_codec_reg_cache - Reset cached codec registers to
108 * their default values.
109 *
110 * @wm8400: pointer to local driver data structure
111 */
112void wm8400_reset_codec_reg_cache(struct wm8400 *wm8400)
113{
114	regmap_reinit_cache(wm8400->regmap, &wm8400_regmap_config);
115}
116EXPORT_SYMBOL_GPL(wm8400_reset_codec_reg_cache);
117
118#if IS_ENABLED(CONFIG_I2C)
119static int wm8400_i2c_probe(struct i2c_client *i2c)
 
120{
121	struct wm8400 *wm8400;
122
123	wm8400 = devm_kzalloc(&i2c->dev, sizeof(struct wm8400), GFP_KERNEL);
124	if (!wm8400)
125		return -ENOMEM;
126
127	wm8400->regmap = devm_regmap_init_i2c(i2c, &wm8400_regmap_config);
128	if (IS_ERR(wm8400->regmap))
129		return PTR_ERR(wm8400->regmap);
130
131	wm8400->dev = &i2c->dev;
132	i2c_set_clientdata(i2c, wm8400);
133
134	return wm8400_init(wm8400, dev_get_platdata(&i2c->dev));
135}
136
137static const struct i2c_device_id wm8400_i2c_id[] = {
138       { "wm8400", 0 },
139       { }
140};
141
142static struct i2c_driver wm8400_i2c_driver = {
143	.driver = {
144		.name = "WM8400",
145	},
146	.probe = wm8400_i2c_probe,
147	.id_table = wm8400_i2c_id,
148};
149#endif
150
151static int __init wm8400_driver_init(void)
152{
153	int ret = -ENODEV;
154
155#if IS_ENABLED(CONFIG_I2C)
156	ret = i2c_add_driver(&wm8400_i2c_driver);
157	if (ret != 0)
158		pr_err("Failed to register I2C driver: %d\n", ret);
159#endif
160
161	return ret;
162}
163subsys_initcall(wm8400_driver_init);

  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, &reg);
 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, &reg);
 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);