linux/drivers/mfd/wm8400-core.c
<<
>>
Prefs
   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                .mfd_data = wm8400,
 249        };
 250
 251        return mfd_add_devices(wm8400->dev, -1, &cell, 1, NULL, 0);
 252}
 253
 254/*
 255 * wm8400_init - Generic initialisation
 256 *
 257 * The WM8400 can be configured as either an I2C or SPI device.  Probe
 258 * functions for each bus set up the accessors then call into this to
 259 * set up the device itself.
 260 */
 261static int wm8400_init(struct wm8400 *wm8400,
 262                       struct wm8400_platform_data *pdata)
 263{
 264        u16 reg;
 265        int ret, i;
 266
 267        mutex_init(&wm8400->io_lock);
 268
 269        dev_set_drvdata(wm8400->dev, wm8400);
 270
 271        /* Check that this is actually a WM8400 */
 272        ret = wm8400->read_dev(wm8400->io_data, WM8400_RESET_ID, 1, &reg);
 273        if (ret != 0) {
 274                dev_err(wm8400->dev, "Chip ID register read failed\n");
 275                return -EIO;
 276        }
 277        if (be16_to_cpu(reg) != reg_data[WM8400_RESET_ID].default_val) {
 278                dev_err(wm8400->dev, "Device is not a WM8400, ID is %x\n",
 279                        be16_to_cpu(reg));
 280                return -ENODEV;
 281        }
 282
 283        /* We don't know what state the hardware is in and since this
 284         * is a PMIC we can't reset it safely so initialise the register
 285         * cache from the hardware.
 286         */
 287        ret = wm8400->read_dev(wm8400->io_data, 0,
 288                               ARRAY_SIZE(wm8400->reg_cache),
 289                               wm8400->reg_cache);
 290        if (ret != 0) {
 291                dev_err(wm8400->dev, "Register cache read failed\n");
 292                return -EIO;
 293        }
 294        for (i = 0; i < ARRAY_SIZE(wm8400->reg_cache); i++)
 295                wm8400->reg_cache[i] = be16_to_cpu(wm8400->reg_cache[i]);
 296
 297        /* If the codec is in reset use hard coded values */
 298        if (!(wm8400->reg_cache[WM8400_POWER_MANAGEMENT_1] & WM8400_CODEC_ENA))
 299                for (i = 0; i < ARRAY_SIZE(wm8400->reg_cache); i++)
 300                        if (reg_data[i].is_codec)
 301                                wm8400->reg_cache[i] = reg_data[i].default_val;
 302
 303        ret = wm8400_read(wm8400, WM8400_ID, 1, &reg);
 304        if (ret != 0) {
 305                dev_err(wm8400->dev, "ID register read failed: %d\n", ret);
 306                return ret;
 307        }
 308        reg = (reg & WM8400_CHIP_REV_MASK) >> WM8400_CHIP_REV_SHIFT;
 309        dev_info(wm8400->dev, "WM8400 revision %x\n", reg);
 310
 311        ret = wm8400_register_codec(wm8400);
 312        if (ret != 0) {
 313                dev_err(wm8400->dev, "Failed to register codec\n");
 314                goto err_children;
 315        }
 316
 317        if (pdata && pdata->platform_init) {
 318                ret = pdata->platform_init(wm8400->dev);
 319                if (ret != 0) {
 320                        dev_err(wm8400->dev, "Platform init failed: %d\n",
 321                                ret);
 322                        goto err_children;
 323                }
 324        } else
 325                dev_warn(wm8400->dev, "No platform initialisation supplied\n");
 326
 327        return 0;
 328
 329err_children:
 330        mfd_remove_devices(wm8400->dev);
 331        return ret;
 332}
 333
 334static void wm8400_release(struct wm8400 *wm8400)
 335{
 336        mfd_remove_devices(wm8400->dev);
 337}
 338
 339#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
 340static int wm8400_i2c_read(void *io_data, char reg, int count, u16 *dest)
 341{
 342        struct i2c_client *i2c = io_data;
 343        struct i2c_msg xfer[2];
 344        int ret;
 345
 346        /* Write register */
 347        xfer[0].addr = i2c->addr;
 348        xfer[0].flags = 0;
 349        xfer[0].len = 1;
 350        xfer[0].buf = &reg;
 351
 352        /* Read data */
 353        xfer[1].addr = i2c->addr;
 354        xfer[1].flags = I2C_M_RD;
 355        xfer[1].len = count * sizeof(u16);
 356        xfer[1].buf = (u8 *)dest;
 357
 358        ret = i2c_transfer(i2c->adapter, xfer, 2);
 359        if (ret == 2)
 360                ret = 0;
 361        else if (ret >= 0)
 362                ret = -EIO;
 363
 364        return ret;
 365}
 366
 367static int wm8400_i2c_write(void *io_data, char reg, int count, const u16 *src)
 368{
 369        struct i2c_client *i2c = io_data;
 370        u8 *msg;
 371        int ret;
 372
 373        /* We add 1 byte for device register - ideally I2C would gather. */
 374        msg = kmalloc((count * sizeof(u16)) + 1, GFP_KERNEL);
 375        if (msg == NULL)
 376                return -ENOMEM;
 377
 378        msg[0] = reg;
 379        memcpy(&msg[1], src, count * sizeof(u16));
 380
 381        ret = i2c_master_send(i2c, msg, (count * sizeof(u16)) + 1);
 382
 383        if (ret == (count * 2) + 1)
 384                ret = 0;
 385        else if (ret >= 0)
 386                ret = -EIO;
 387
 388        kfree(msg);
 389
 390        return ret;
 391}
 392
 393static int wm8400_i2c_probe(struct i2c_client *i2c,
 394                            const struct i2c_device_id *id)
 395{
 396        struct wm8400 *wm8400;
 397        int ret;
 398
 399        wm8400 = kzalloc(sizeof(struct wm8400), GFP_KERNEL);
 400        if (wm8400 == NULL) {
 401                ret = -ENOMEM;
 402                goto err;
 403        }
 404
 405        wm8400->io_data = i2c;
 406        wm8400->read_dev = wm8400_i2c_read;
 407        wm8400->write_dev = wm8400_i2c_write;
 408        wm8400->dev = &i2c->dev;
 409        i2c_set_clientdata(i2c, wm8400);
 410
 411        ret = wm8400_init(wm8400, i2c->dev.platform_data);
 412        if (ret != 0)
 413                goto struct_err;
 414
 415        return 0;
 416
 417struct_err:
 418        kfree(wm8400);
 419err:
 420        return ret;
 421}
 422
 423static int wm8400_i2c_remove(struct i2c_client *i2c)
 424{
 425        struct wm8400 *wm8400 = i2c_get_clientdata(i2c);
 426
 427        wm8400_release(wm8400);
 428        kfree(wm8400);
 429
 430        return 0;
 431}
 432
 433static const struct i2c_device_id wm8400_i2c_id[] = {
 434       { "wm8400", 0 },
 435       { }
 436};
 437MODULE_DEVICE_TABLE(i2c, wm8400_i2c_id);
 438
 439static struct i2c_driver wm8400_i2c_driver = {
 440        .driver = {
 441                .name = "WM8400",
 442                .owner = THIS_MODULE,
 443        },
 444        .probe    = wm8400_i2c_probe,
 445        .remove   = wm8400_i2c_remove,
 446        .id_table = wm8400_i2c_id,
 447};
 448#endif
 449
 450static int __init wm8400_module_init(void)
 451{
 452        int ret = -ENODEV;
 453
 454#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
 455        ret = i2c_add_driver(&wm8400_i2c_driver);
 456        if (ret != 0)
 457                pr_err("Failed to register I2C driver: %d\n", ret);
 458#endif
 459
 460        return ret;
 461}
 462subsys_initcall(wm8400_module_init);
 463
 464static void __exit wm8400_module_exit(void)
 465{
 466#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
 467        i2c_del_driver(&wm8400_i2c_driver);
 468#endif
 469}
 470module_exit(wm8400_module_exit);
 471
 472MODULE_LICENSE("GPL");
 473MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 474