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v6.8
  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);
 
 
 
 
 
 
 
 
 
 
 
v3.1
 
  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/bug.h>
 
 16#include <linux/i2c.h>
 17#include <linux/kernel.h>
 18#include <linux/mfd/core.h>
 19#include <linux/mfd/wm8400-private.h>
 20#include <linux/mfd/wm8400-audio.h>
 
 21#include <linux/slab.h>
 22
 23static struct {
 24	u16  readable;    /* Mask of readable bits */
 25	u16  writable;    /* Mask of writable bits */
 26	u16  vol;         /* Mask of volatile bits */
 27	int  is_codec;    /* Register controlled by codec reset */
 28	u16  default_val; /* Value on reset */
 29} reg_data[] = {
 30	{ 0xFFFF, 0xFFFF, 0x0000, 0, 0x6172 }, /* R0 */
 31	{ 0x7000, 0x0000, 0x8000, 0, 0x0000 }, /* R1 */
 32	{ 0xFF17, 0xFF17, 0x0000, 0, 0x0000 }, /* R2 */
 33	{ 0xEBF3, 0xEBF3, 0x0000, 1, 0x6000 }, /* R3 */
 34	{ 0x3CF3, 0x3CF3, 0x0000, 1, 0x0000 }, /* R4  */
 35	{ 0xF1F8, 0xF1F8, 0x0000, 1, 0x4050 }, /* R5  */
 36	{ 0xFC1F, 0xFC1F, 0x0000, 1, 0x4000 }, /* R6  */
 37	{ 0xDFDE, 0xDFDE, 0x0000, 1, 0x01C8 }, /* R7  */
 38	{ 0xFCFC, 0xFCFC, 0x0000, 1, 0x0000 }, /* R8  */
 39	{ 0xEFFF, 0xEFFF, 0x0000, 1, 0x0040 }, /* R9  */
 40	{ 0xEFFF, 0xEFFF, 0x0000, 1, 0x0040 }, /* R10 */
 41	{ 0x27F7, 0x27F7, 0x0000, 1, 0x0004 }, /* R11 */
 42	{ 0x01FF, 0x01FF, 0x0000, 1, 0x00C0 }, /* R12 */
 43	{ 0x01FF, 0x01FF, 0x0000, 1, 0x00C0 }, /* R13 */
 44	{ 0x1FEF, 0x1FEF, 0x0000, 1, 0x0000 }, /* R14 */
 45	{ 0x0163, 0x0163, 0x0000, 1, 0x0100 }, /* R15 */
 46	{ 0x01FF, 0x01FF, 0x0000, 1, 0x00C0 }, /* R16 */
 47	{ 0x01FF, 0x01FF, 0x0000, 1, 0x00C0 }, /* R17 */
 48	{ 0x1FFF, 0x0FFF, 0x0000, 1, 0x0000 }, /* R18 */
 49	{ 0xFFFF, 0xFFFF, 0x0000, 1, 0x1000 }, /* R19 */
 50	{ 0xFFFF, 0xFFFF, 0x0000, 1, 0x1010 }, /* R20 */
 51	{ 0xFFFF, 0xFFFF, 0x0000, 1, 0x1010 }, /* R21 */
 52	{ 0x0FDD, 0x0FDD, 0x0000, 1, 0x8000 }, /* R22 */
 53	{ 0x1FFF, 0x1FFF, 0x0000, 1, 0x0800 }, /* R23 */
 54	{ 0x0000, 0x01DF, 0x0000, 1, 0x008B }, /* R24 */
 55	{ 0x0000, 0x01DF, 0x0000, 1, 0x008B }, /* R25 */
 56	{ 0x0000, 0x01DF, 0x0000, 1, 0x008B }, /* R26 */
 57	{ 0x0000, 0x01DF, 0x0000, 1, 0x008B }, /* R27 */
 58	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R28 */
 59	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R29 */
 60	{ 0x0000, 0x0077, 0x0000, 1, 0x0066 }, /* R30 */
 61	{ 0x0000, 0x0033, 0x0000, 1, 0x0022 }, /* R31 */
 62	{ 0x0000, 0x01FF, 0x0000, 1, 0x0079 }, /* R32 */
 63	{ 0x0000, 0x01FF, 0x0000, 1, 0x0079 }, /* R33 */
 64	{ 0x0000, 0x0003, 0x0000, 1, 0x0003 }, /* R34 */
 65	{ 0x0000, 0x01FF, 0x0000, 1, 0x0003 }, /* R35 */
 66	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R36 */
 67	{ 0x0000, 0x003F, 0x0000, 1, 0x0100 }, /* R37 */
 68	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R38 */
 69	{ 0x0000, 0x000F, 0x0000, 0, 0x0000 }, /* R39 */
 70	{ 0x0000, 0x00FF, 0x0000, 1, 0x0000 }, /* R40 */
 71	{ 0x0000, 0x01B7, 0x0000, 1, 0x0000 }, /* R41 */
 72	{ 0x0000, 0x01B7, 0x0000, 1, 0x0000 }, /* R42 */
 73	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R43 */
 74	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R44 */
 75	{ 0x0000, 0x00FD, 0x0000, 1, 0x0000 }, /* R45 */
 76	{ 0x0000, 0x00FD, 0x0000, 1, 0x0000 }, /* R46 */
 77	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R47 */
 78	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R48 */
 79	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R49 */
 80	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R50 */
 81	{ 0x0000, 0x01B3, 0x0000, 1, 0x0180 }, /* R51 */
 82	{ 0x0000, 0x0077, 0x0000, 1, 0x0000 }, /* R52 */
 83	{ 0x0000, 0x0077, 0x0000, 1, 0x0000 }, /* R53 */
 84	{ 0x0000, 0x00FF, 0x0000, 1, 0x0000 }, /* R54 */
 85	{ 0x0000, 0x0001, 0x0000, 1, 0x0000 }, /* R55 */
 86	{ 0x0000, 0x003F, 0x0000, 1, 0x0000 }, /* R56 */
 87	{ 0x0000, 0x004F, 0x0000, 1, 0x0000 }, /* R57 */
 88	{ 0x0000, 0x00FD, 0x0000, 1, 0x0000 }, /* R58 */
 89	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R59 */
 90	{ 0x1FFF, 0x1FFF, 0x0000, 1, 0x0000 }, /* R60 */
 91	{ 0xFFFF, 0xFFFF, 0x0000, 1, 0x0000 }, /* R61 */
 92	{ 0x03FF, 0x03FF, 0x0000, 1, 0x0000 }, /* R62 */
 93	{ 0x007F, 0x007F, 0x0000, 1, 0x0000 }, /* R63 */
 94	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R64 */
 95	{ 0xDFFF, 0xDFFF, 0x0000, 0, 0x0000 }, /* R65 */
 96	{ 0xDFFF, 0xDFFF, 0x0000, 0, 0x0000 }, /* R66 */
 97	{ 0xDFFF, 0xDFFF, 0x0000, 0, 0x0000 }, /* R67 */
 98	{ 0xDFFF, 0xDFFF, 0x0000, 0, 0x0000 }, /* R68 */
 99	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R69 */
100	{ 0xFFFF, 0xFFFF, 0x0000, 0, 0x4400 }, /* R70 */
101	{ 0x23FF, 0x23FF, 0x0000, 0, 0x0000 }, /* R71 */
102	{ 0xFFFF, 0xFFFF, 0x0000, 0, 0x4400 }, /* R72 */
103	{ 0x23FF, 0x23FF, 0x0000, 0, 0x0000 }, /* R73 */
104	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R74 */
105	{ 0x000E, 0x000E, 0x0000, 0, 0x0008 }, /* R75 */
106	{ 0xE00F, 0xE00F, 0x0000, 0, 0x0000 }, /* R76 */
107	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R77 */
108	{ 0x03C0, 0x03C0, 0x0000, 0, 0x02C0 }, /* R78 */
109	{ 0xFFFF, 0x0000, 0xffff, 0, 0x0000 }, /* R79 */
110	{ 0xFFFF, 0xFFFF, 0x0000, 0, 0x0000 }, /* R80 */
111	{ 0xFFFF, 0x0000, 0xffff, 0, 0x0000 }, /* R81 */
112	{ 0x2BFF, 0x0000, 0xffff, 0, 0x0000 }, /* R82 */
113	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R83 */
114	{ 0x80FF, 0x80FF, 0x0000, 0, 0x00ff }, /* R84 */
115};
116
117static int wm8400_read(struct wm8400 *wm8400, u8 reg, int num_regs, u16 *dest)
118{
119	int i, ret = 0;
120
121	BUG_ON(reg + num_regs > ARRAY_SIZE(wm8400->reg_cache));
122
123	/* If there are any volatile reads then read back the entire block */
124	for (i = reg; i < reg + num_regs; i++)
125		if (reg_data[i].vol) {
126			ret = wm8400->read_dev(wm8400->io_data, reg,
127					       num_regs, dest);
128			if (ret != 0)
129				return ret;
130			for (i = 0; i < num_regs; i++)
131				dest[i] = be16_to_cpu(dest[i]);
132
133			return 0;
134		}
135
136	/* Otherwise use the cache */
137	memcpy(dest, &wm8400->reg_cache[reg], num_regs * sizeof(u16));
138
139	return 0;
140}
141
142static int wm8400_write(struct wm8400 *wm8400, u8 reg, int num_regs,
143			u16 *src)
144{
145	int ret, i;
146
147	BUG_ON(reg + num_regs > ARRAY_SIZE(wm8400->reg_cache));
148
149	for (i = 0; i < num_regs; i++) {
150		BUG_ON(!reg_data[reg + i].writable);
151		wm8400->reg_cache[reg + i] = src[i];
152		src[i] = cpu_to_be16(src[i]);
153	}
154
155	/* Do the actual I/O */
156	ret = wm8400->write_dev(wm8400->io_data, reg, num_regs, src);
157	if (ret != 0)
158		return -EIO;
159
160	return 0;
161}
162
163/**
164 * wm8400_reg_read - Single register read
165 *
166 * @wm8400: Pointer to wm8400 control structure
167 * @reg:    Register to read
168 *
169 * @return  Read value
170 */
171u16 wm8400_reg_read(struct wm8400 *wm8400, u8 reg)
172{
173	u16 val;
174
175	mutex_lock(&wm8400->io_lock);
176
177	wm8400_read(wm8400, reg, 1, &val);
178
179	mutex_unlock(&wm8400->io_lock);
180
181	return val;
182}
183EXPORT_SYMBOL_GPL(wm8400_reg_read);
184
185int wm8400_block_read(struct wm8400 *wm8400, u8 reg, int count, u16 *data)
186{
187	int ret;
188
189	mutex_lock(&wm8400->io_lock);
190
191	ret = wm8400_read(wm8400, reg, count, data);
192
193	mutex_unlock(&wm8400->io_lock);
194
195	return ret;
196}
197EXPORT_SYMBOL_GPL(wm8400_block_read);
198
199/**
200 * wm8400_set_bits - Bitmask write
201 *
202 * @wm8400: Pointer to wm8400 control structure
203 * @reg:    Register to access
204 * @mask:   Mask of bits to change
205 * @val:    Value to set for masked bits
206 */
207int wm8400_set_bits(struct wm8400 *wm8400, u8 reg, u16 mask, u16 val)
208{
209	u16 tmp;
210	int ret;
211
212	mutex_lock(&wm8400->io_lock);
213
214	ret = wm8400_read(wm8400, reg, 1, &tmp);
215	tmp = (tmp & ~mask) | val;
216	if (ret == 0)
217		ret = wm8400_write(wm8400, reg, 1, &tmp);
218
219	mutex_unlock(&wm8400->io_lock);
220
221	return ret;
222}
223EXPORT_SYMBOL_GPL(wm8400_set_bits);
224
225/**
226 * wm8400_reset_codec_reg_cache - Reset cached codec registers to
227 * their default values.
228 */
229void wm8400_reset_codec_reg_cache(struct wm8400 *wm8400)
230{
231	int i;
232
233	mutex_lock(&wm8400->io_lock);
234
235	/* Reset all codec registers to their initial value */
236	for (i = 0; i < ARRAY_SIZE(wm8400->reg_cache); i++)
237		if (reg_data[i].is_codec)
238			wm8400->reg_cache[i] = reg_data[i].default_val;
239
240	mutex_unlock(&wm8400->io_lock);
241}
242EXPORT_SYMBOL_GPL(wm8400_reset_codec_reg_cache);
243
244static int wm8400_register_codec(struct wm8400 *wm8400)
245{
246	struct mfd_cell cell = {
247		.name = "wm8400-codec",
248		.platform_data = wm8400,
249		.pdata_size = sizeof(*wm8400),
250	};
251
252	return mfd_add_devices(wm8400->dev, -1, &cell, 1, NULL, 0);
253}
254
255/*
256 * wm8400_init - Generic initialisation
257 *
258 * The WM8400 can be configured as either an I2C or SPI device.  Probe
259 * functions for each bus set up the accessors then call into this to
260 * set up the device itself.
261 */
262static int wm8400_init(struct wm8400 *wm8400,
263		       struct wm8400_platform_data *pdata)
264{
265	u16 reg;
266	int ret, i;
267
268	mutex_init(&wm8400->io_lock);
269
270	dev_set_drvdata(wm8400->dev, wm8400);
271
272	/* Check that this is actually a WM8400 */
273	ret = wm8400->read_dev(wm8400->io_data, WM8400_RESET_ID, 1, &reg);
274	if (ret != 0) {
275		dev_err(wm8400->dev, "Chip ID register read failed\n");
276		return -EIO;
277	}
278	if (be16_to_cpu(reg) != reg_data[WM8400_RESET_ID].default_val) {
279		dev_err(wm8400->dev, "Device is not a WM8400, ID is %x\n",
280			be16_to_cpu(reg));
281		return -ENODEV;
282	}
283
284	/* We don't know what state the hardware is in and since this
285	 * is a PMIC we can't reset it safely so initialise the register
286	 * cache from the hardware.
287	 */
288	ret = wm8400->read_dev(wm8400->io_data, 0,
289			       ARRAY_SIZE(wm8400->reg_cache),
290			       wm8400->reg_cache);
291	if (ret != 0) {
292		dev_err(wm8400->dev, "Register cache read failed\n");
293		return -EIO;
294	}
295	for (i = 0; i < ARRAY_SIZE(wm8400->reg_cache); i++)
296		wm8400->reg_cache[i] = be16_to_cpu(wm8400->reg_cache[i]);
297
298	/* If the codec is in reset use hard coded values */
299	if (!(wm8400->reg_cache[WM8400_POWER_MANAGEMENT_1] & WM8400_CODEC_ENA))
300		for (i = 0; i < ARRAY_SIZE(wm8400->reg_cache); i++)
301			if (reg_data[i].is_codec)
302				wm8400->reg_cache[i] = reg_data[i].default_val;
303
304	ret = wm8400_read(wm8400, WM8400_ID, 1, &reg);
305	if (ret != 0) {
306		dev_err(wm8400->dev, "ID register read failed: %d\n", ret);
307		return ret;
308	}
309	reg = (reg & WM8400_CHIP_REV_MASK) >> WM8400_CHIP_REV_SHIFT;
310	dev_info(wm8400->dev, "WM8400 revision %x\n", reg);
311
312	ret = wm8400_register_codec(wm8400);
313	if (ret != 0) {
314		dev_err(wm8400->dev, "Failed to register codec\n");
315		goto err_children;
316	}
317
318	if (pdata && pdata->platform_init) {
319		ret = pdata->platform_init(wm8400->dev);
320		if (ret != 0) {
321			dev_err(wm8400->dev, "Platform init failed: %d\n",
322				ret);
323			goto err_children;
324		}
325	} else
326		dev_warn(wm8400->dev, "No platform initialisation supplied\n");
327
328	return 0;
329
330err_children:
331	mfd_remove_devices(wm8400->dev);
332	return ret;
333}
334
335static void wm8400_release(struct wm8400 *wm8400)
336{
337	mfd_remove_devices(wm8400->dev);
338}
339
340#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
341static int wm8400_i2c_read(void *io_data, char reg, int count, u16 *dest)
342{
343	struct i2c_client *i2c = io_data;
344	struct i2c_msg xfer[2];
345	int ret;
346
347	/* Write register */
348	xfer[0].addr = i2c->addr;
349	xfer[0].flags = 0;
350	xfer[0].len = 1;
351	xfer[0].buf = &reg;
352
353	/* Read data */
354	xfer[1].addr = i2c->addr;
355	xfer[1].flags = I2C_M_RD;
356	xfer[1].len = count * sizeof(u16);
357	xfer[1].buf = (u8 *)dest;
358
359	ret = i2c_transfer(i2c->adapter, xfer, 2);
360	if (ret == 2)
361		ret = 0;
362	else if (ret >= 0)
363		ret = -EIO;
364
365	return ret;
 
 
 
 
 
 
 
 
366}
 
367
368static int wm8400_i2c_write(void *io_data, char reg, int count, const u16 *src)
 
369{
370	struct i2c_client *i2c = io_data;
371	u8 *msg;
372	int ret;
373
374	/* We add 1 byte for device register - ideally I2C would gather. */
375	msg = kmalloc((count * sizeof(u16)) + 1, GFP_KERNEL);
376	if (msg == NULL)
377		return -ENOMEM;
378
379	msg[0] = reg;
380	memcpy(&msg[1], src, count * sizeof(u16));
381
382	ret = i2c_master_send(i2c, msg, (count * sizeof(u16)) + 1);
383
384	if (ret == (count * 2) + 1)
385		ret = 0;
386	else if (ret >= 0)
387		ret = -EIO;
388
389	kfree(msg);
390
391	return ret;
392}
393
394static int wm8400_i2c_probe(struct i2c_client *i2c,
395			    const struct i2c_device_id *id)
396{
397	struct wm8400 *wm8400;
398	int ret;
399
400	wm8400 = kzalloc(sizeof(struct wm8400), GFP_KERNEL);
401	if (wm8400 == NULL) {
402		ret = -ENOMEM;
403		goto err;
404	}
405
406	wm8400->io_data = i2c;
407	wm8400->read_dev = wm8400_i2c_read;
408	wm8400->write_dev = wm8400_i2c_write;
409	wm8400->dev = &i2c->dev;
410	i2c_set_clientdata(i2c, wm8400);
411
412	ret = wm8400_init(wm8400, i2c->dev.platform_data);
413	if (ret != 0)
414		goto struct_err;
415
416	return 0;
417
418struct_err:
419	kfree(wm8400);
420err:
421	return ret;
422}
423
424static int wm8400_i2c_remove(struct i2c_client *i2c)
425{
426	struct wm8400 *wm8400 = i2c_get_clientdata(i2c);
427
428	wm8400_release(wm8400);
429	kfree(wm8400);
430
431	return 0;
432}
433
434static const struct i2c_device_id wm8400_i2c_id[] = {
435       { "wm8400", 0 },
436       { }
437};
438MODULE_DEVICE_TABLE(i2c, wm8400_i2c_id);
439
440static struct i2c_driver wm8400_i2c_driver = {
441	.driver = {
442		.name = "WM8400",
443		.owner = THIS_MODULE,
444	},
445	.probe    = wm8400_i2c_probe,
446	.remove   = wm8400_i2c_remove,
447	.id_table = wm8400_i2c_id,
448};
449#endif
450
451static int __init wm8400_module_init(void)
452{
453	int ret = -ENODEV;
454
455#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
456	ret = i2c_add_driver(&wm8400_i2c_driver);
457	if (ret != 0)
458		pr_err("Failed to register I2C driver: %d\n", ret);
459#endif
460
461	return ret;
462}
463subsys_initcall(wm8400_module_init);
464
465static void __exit wm8400_module_exit(void)
466{
467#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
468	i2c_del_driver(&wm8400_i2c_driver);
469#endif
470}
471module_exit(wm8400_module_exit);
472
473MODULE_LICENSE("GPL");
474MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");