linux/drivers/mfd/aat2870-core.c
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   1/*
   2 * linux/drivers/mfd/aat2870-core.c
   3 *
   4 * Copyright (c) 2011, NVIDIA Corporation.
   5 * Author: Jin Park <jinyoungp@nvidia.com>
   6 *
   7 * This program is free software; you can redistribute it and/or
   8 * modify it under the terms of the GNU General Public License
   9 * version 2 as published by the Free Software Foundation.
  10 *
  11 * This program is distributed in the hope that it will be useful, but
  12 * WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 * General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program; if not, write to the Free Software
  18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  19 * 02110-1301 USA
  20 */
  21
  22#include <linux/kernel.h>
  23#include <linux/module.h>
  24#include <linux/init.h>
  25#include <linux/debugfs.h>
  26#include <linux/slab.h>
  27#include <linux/uaccess.h>
  28#include <linux/i2c.h>
  29#include <linux/delay.h>
  30#include <linux/gpio.h>
  31#include <linux/mfd/core.h>
  32#include <linux/mfd/aat2870.h>
  33#include <linux/regulator/machine.h>
  34
  35static struct aat2870_register aat2870_regs[AAT2870_REG_NUM] = {
  36        /* readable, writeable, value */
  37        { 0, 1, 0x00 }, /* 0x00 AAT2870_BL_CH_EN */
  38        { 0, 1, 0x16 }, /* 0x01 AAT2870_BLM */
  39        { 0, 1, 0x16 }, /* 0x02 AAT2870_BLS */
  40        { 0, 1, 0x56 }, /* 0x03 AAT2870_BL1 */
  41        { 0, 1, 0x56 }, /* 0x04 AAT2870_BL2 */
  42        { 0, 1, 0x56 }, /* 0x05 AAT2870_BL3 */
  43        { 0, 1, 0x56 }, /* 0x06 AAT2870_BL4 */
  44        { 0, 1, 0x56 }, /* 0x07 AAT2870_BL5 */
  45        { 0, 1, 0x56 }, /* 0x08 AAT2870_BL6 */
  46        { 0, 1, 0x56 }, /* 0x09 AAT2870_BL7 */
  47        { 0, 1, 0x56 }, /* 0x0A AAT2870_BL8 */
  48        { 0, 1, 0x00 }, /* 0x0B AAT2870_FLR */
  49        { 0, 1, 0x03 }, /* 0x0C AAT2870_FM */
  50        { 0, 1, 0x03 }, /* 0x0D AAT2870_FS */
  51        { 0, 1, 0x10 }, /* 0x0E AAT2870_ALS_CFG0 */
  52        { 0, 1, 0x06 }, /* 0x0F AAT2870_ALS_CFG1 */
  53        { 0, 1, 0x00 }, /* 0x10 AAT2870_ALS_CFG2 */
  54        { 1, 0, 0x00 }, /* 0x11 AAT2870_AMB */
  55        { 0, 1, 0x00 }, /* 0x12 AAT2870_ALS0 */
  56        { 0, 1, 0x00 }, /* 0x13 AAT2870_ALS1 */
  57        { 0, 1, 0x00 }, /* 0x14 AAT2870_ALS2 */
  58        { 0, 1, 0x00 }, /* 0x15 AAT2870_ALS3 */
  59        { 0, 1, 0x00 }, /* 0x16 AAT2870_ALS4 */
  60        { 0, 1, 0x00 }, /* 0x17 AAT2870_ALS5 */
  61        { 0, 1, 0x00 }, /* 0x18 AAT2870_ALS6 */
  62        { 0, 1, 0x00 }, /* 0x19 AAT2870_ALS7 */
  63        { 0, 1, 0x00 }, /* 0x1A AAT2870_ALS8 */
  64        { 0, 1, 0x00 }, /* 0x1B AAT2870_ALS9 */
  65        { 0, 1, 0x00 }, /* 0x1C AAT2870_ALSA */
  66        { 0, 1, 0x00 }, /* 0x1D AAT2870_ALSB */
  67        { 0, 1, 0x00 }, /* 0x1E AAT2870_ALSC */
  68        { 0, 1, 0x00 }, /* 0x1F AAT2870_ALSD */
  69        { 0, 1, 0x00 }, /* 0x20 AAT2870_ALSE */
  70        { 0, 1, 0x00 }, /* 0x21 AAT2870_ALSF */
  71        { 0, 1, 0x00 }, /* 0x22 AAT2870_SUB_SET */
  72        { 0, 1, 0x00 }, /* 0x23 AAT2870_SUB_CTRL */
  73        { 0, 1, 0x00 }, /* 0x24 AAT2870_LDO_AB */
  74        { 0, 1, 0x00 }, /* 0x25 AAT2870_LDO_CD */
  75        { 0, 1, 0x00 }, /* 0x26 AAT2870_LDO_EN */
  76};
  77
  78static struct mfd_cell aat2870_devs[] = {
  79        {
  80                .name = "aat2870-backlight",
  81                .id = AAT2870_ID_BL,
  82                .pdata_size = sizeof(struct aat2870_bl_platform_data),
  83        },
  84        {
  85                .name = "aat2870-regulator",
  86                .id = AAT2870_ID_LDOA,
  87                .pdata_size = sizeof(struct regulator_init_data),
  88        },
  89        {
  90                .name = "aat2870-regulator",
  91                .id = AAT2870_ID_LDOB,
  92                .pdata_size = sizeof(struct regulator_init_data),
  93        },
  94        {
  95                .name = "aat2870-regulator",
  96                .id = AAT2870_ID_LDOC,
  97                .pdata_size = sizeof(struct regulator_init_data),
  98        },
  99        {
 100                .name = "aat2870-regulator",
 101                .id = AAT2870_ID_LDOD,
 102                .pdata_size = sizeof(struct regulator_init_data),
 103        },
 104};
 105
 106static int __aat2870_read(struct aat2870_data *aat2870, u8 addr, u8 *val)
 107{
 108        int ret;
 109
 110        if (addr >= AAT2870_REG_NUM) {
 111                dev_err(aat2870->dev, "Invalid address, 0x%02x\n", addr);
 112                return -EINVAL;
 113        }
 114
 115        if (!aat2870->reg_cache[addr].readable) {
 116                *val = aat2870->reg_cache[addr].value;
 117                goto out;
 118        }
 119
 120        ret = i2c_master_send(aat2870->client, &addr, 1);
 121        if (ret < 0)
 122                return ret;
 123        if (ret != 1)
 124                return -EIO;
 125
 126        ret = i2c_master_recv(aat2870->client, val, 1);
 127        if (ret < 0)
 128                return ret;
 129        if (ret != 1)
 130                return -EIO;
 131
 132out:
 133        dev_dbg(aat2870->dev, "read: addr=0x%02x, val=0x%02x\n", addr, *val);
 134        return 0;
 135}
 136
 137static int __aat2870_write(struct aat2870_data *aat2870, u8 addr, u8 val)
 138{
 139        u8 msg[2];
 140        int ret;
 141
 142        if (addr >= AAT2870_REG_NUM) {
 143                dev_err(aat2870->dev, "Invalid address, 0x%02x\n", addr);
 144                return -EINVAL;
 145        }
 146
 147        if (!aat2870->reg_cache[addr].writeable) {
 148                dev_err(aat2870->dev, "Address 0x%02x is not writeable\n",
 149                        addr);
 150                return -EINVAL;
 151        }
 152
 153        msg[0] = addr;
 154        msg[1] = val;
 155        ret = i2c_master_send(aat2870->client, msg, 2);
 156        if (ret < 0)
 157                return ret;
 158        if (ret != 2)
 159                return -EIO;
 160
 161        aat2870->reg_cache[addr].value = val;
 162
 163        dev_dbg(aat2870->dev, "write: addr=0x%02x, val=0x%02x\n", addr, val);
 164        return 0;
 165}
 166
 167static int aat2870_read(struct aat2870_data *aat2870, u8 addr, u8 *val)
 168{
 169        int ret;
 170
 171        mutex_lock(&aat2870->io_lock);
 172        ret = __aat2870_read(aat2870, addr, val);
 173        mutex_unlock(&aat2870->io_lock);
 174
 175        return ret;
 176}
 177
 178static int aat2870_write(struct aat2870_data *aat2870, u8 addr, u8 val)
 179{
 180        int ret;
 181
 182        mutex_lock(&aat2870->io_lock);
 183        ret = __aat2870_write(aat2870, addr, val);
 184        mutex_unlock(&aat2870->io_lock);
 185
 186        return ret;
 187}
 188
 189static int aat2870_update(struct aat2870_data *aat2870, u8 addr, u8 mask,
 190                          u8 val)
 191{
 192        int change;
 193        u8 old_val, new_val;
 194        int ret;
 195
 196        mutex_lock(&aat2870->io_lock);
 197
 198        ret = __aat2870_read(aat2870, addr, &old_val);
 199        if (ret)
 200                goto out_unlock;
 201
 202        new_val = (old_val & ~mask) | (val & mask);
 203        change = old_val != new_val;
 204        if (change)
 205                ret = __aat2870_write(aat2870, addr, new_val);
 206
 207out_unlock:
 208        mutex_unlock(&aat2870->io_lock);
 209
 210        return ret;
 211}
 212
 213static inline void aat2870_enable(struct aat2870_data *aat2870)
 214{
 215        if (aat2870->en_pin >= 0)
 216                gpio_set_value(aat2870->en_pin, 1);
 217
 218        aat2870->is_enable = 1;
 219}
 220
 221static inline void aat2870_disable(struct aat2870_data *aat2870)
 222{
 223        if (aat2870->en_pin >= 0)
 224                gpio_set_value(aat2870->en_pin, 0);
 225
 226        aat2870->is_enable = 0;
 227}
 228
 229#ifdef CONFIG_DEBUG_FS
 230static ssize_t aat2870_dump_reg(struct aat2870_data *aat2870, char *buf)
 231{
 232        u8 addr, val;
 233        ssize_t count = 0;
 234        int ret;
 235
 236        count += sprintf(buf, "aat2870 registers\n");
 237        for (addr = 0; addr < AAT2870_REG_NUM; addr++) {
 238                count += sprintf(buf + count, "0x%02x: ", addr);
 239                if (count >= PAGE_SIZE - 1)
 240                        break;
 241
 242                ret = aat2870->read(aat2870, addr, &val);
 243                if (ret == 0)
 244                        count += snprintf(buf + count, PAGE_SIZE - count,
 245                                          "0x%02x", val);
 246                else
 247                        count += snprintf(buf + count, PAGE_SIZE - count,
 248                                          "<read fail: %d>", ret);
 249
 250                if (count >= PAGE_SIZE - 1)
 251                        break;
 252
 253                count += snprintf(buf + count, PAGE_SIZE - count, "\n");
 254                if (count >= PAGE_SIZE - 1)
 255                        break;
 256        }
 257
 258        /* Truncate count; min() would cause a warning */
 259        if (count >= PAGE_SIZE)
 260                count = PAGE_SIZE - 1;
 261
 262        return count;
 263}
 264
 265static ssize_t aat2870_reg_read_file(struct file *file, char __user *user_buf,
 266                                     size_t count, loff_t *ppos)
 267{
 268        struct aat2870_data *aat2870 = file->private_data;
 269        char *buf;
 270        ssize_t ret;
 271
 272        buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 273        if (!buf)
 274                return -ENOMEM;
 275
 276        ret = aat2870_dump_reg(aat2870, buf);
 277        if (ret >= 0)
 278                ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
 279
 280        kfree(buf);
 281
 282        return ret;
 283}
 284
 285static ssize_t aat2870_reg_write_file(struct file *file,
 286                                      const char __user *user_buf, size_t count,
 287                                      loff_t *ppos)
 288{
 289        struct aat2870_data *aat2870 = file->private_data;
 290        char buf[32];
 291        ssize_t buf_size;
 292        char *start = buf;
 293        unsigned long addr, val;
 294        int ret;
 295
 296        buf_size = min(count, (sizeof(buf)-1));
 297        if (copy_from_user(buf, user_buf, buf_size)) {
 298                dev_err(aat2870->dev, "Failed to copy from user\n");
 299                return -EFAULT;
 300        }
 301        buf[buf_size] = 0;
 302
 303        while (*start == ' ')
 304                start++;
 305
 306        addr = simple_strtoul(start, &start, 16);
 307        if (addr >= AAT2870_REG_NUM) {
 308                dev_err(aat2870->dev, "Invalid address, 0x%lx\n", addr);
 309                return -EINVAL;
 310        }
 311
 312        while (*start == ' ')
 313                start++;
 314
 315        ret = kstrtoul(start, 16, &val);
 316        if (ret)
 317                return ret;
 318
 319        ret = aat2870->write(aat2870, (u8)addr, (u8)val);
 320        if (ret)
 321                return ret;
 322
 323        return buf_size;
 324}
 325
 326static const struct file_operations aat2870_reg_fops = {
 327        .open = simple_open,
 328        .read = aat2870_reg_read_file,
 329        .write = aat2870_reg_write_file,
 330};
 331
 332static void aat2870_init_debugfs(struct aat2870_data *aat2870)
 333{
 334        aat2870->dentry_root = debugfs_create_dir("aat2870", NULL);
 335        if (!aat2870->dentry_root) {
 336                dev_warn(aat2870->dev,
 337                         "Failed to create debugfs root directory\n");
 338                return;
 339        }
 340
 341        aat2870->dentry_reg = debugfs_create_file("regs", 0644,
 342                                                  aat2870->dentry_root,
 343                                                  aat2870, &aat2870_reg_fops);
 344        if (!aat2870->dentry_reg)
 345                dev_warn(aat2870->dev,
 346                         "Failed to create debugfs register file\n");
 347}
 348
 349static void aat2870_uninit_debugfs(struct aat2870_data *aat2870)
 350{
 351        debugfs_remove_recursive(aat2870->dentry_root);
 352}
 353#else
 354static inline void aat2870_init_debugfs(struct aat2870_data *aat2870)
 355{
 356}
 357
 358static inline void aat2870_uninit_debugfs(struct aat2870_data *aat2870)
 359{
 360}
 361#endif /* CONFIG_DEBUG_FS */
 362
 363static int aat2870_i2c_probe(struct i2c_client *client,
 364                             const struct i2c_device_id *id)
 365{
 366        struct aat2870_platform_data *pdata = dev_get_platdata(&client->dev);
 367        struct aat2870_data *aat2870;
 368        int i, j;
 369        int ret = 0;
 370
 371        aat2870 = devm_kzalloc(&client->dev, sizeof(struct aat2870_data),
 372                                GFP_KERNEL);
 373        if (!aat2870) {
 374                dev_err(&client->dev,
 375                        "Failed to allocate memory for aat2870\n");
 376                return -ENOMEM;
 377        }
 378
 379        aat2870->dev = &client->dev;
 380        dev_set_drvdata(aat2870->dev, aat2870);
 381
 382        aat2870->client = client;
 383        i2c_set_clientdata(client, aat2870);
 384
 385        aat2870->reg_cache = aat2870_regs;
 386
 387        if (pdata->en_pin < 0)
 388                aat2870->en_pin = -1;
 389        else
 390                aat2870->en_pin = pdata->en_pin;
 391
 392        aat2870->init = pdata->init;
 393        aat2870->uninit = pdata->uninit;
 394        aat2870->read = aat2870_read;
 395        aat2870->write = aat2870_write;
 396        aat2870->update = aat2870_update;
 397
 398        mutex_init(&aat2870->io_lock);
 399
 400        if (aat2870->init)
 401                aat2870->init(aat2870);
 402
 403        if (aat2870->en_pin >= 0) {
 404                ret = devm_gpio_request_one(&client->dev, aat2870->en_pin,
 405                                        GPIOF_OUT_INIT_HIGH, "aat2870-en");
 406                if (ret < 0) {
 407                        dev_err(&client->dev,
 408                                "Failed to request GPIO %d\n", aat2870->en_pin);
 409                        return ret;
 410                }
 411        }
 412
 413        aat2870_enable(aat2870);
 414
 415        for (i = 0; i < pdata->num_subdevs; i++) {
 416                for (j = 0; j < ARRAY_SIZE(aat2870_devs); j++) {
 417                        if ((pdata->subdevs[i].id == aat2870_devs[j].id) &&
 418                                        !strcmp(pdata->subdevs[i].name,
 419                                                aat2870_devs[j].name)) {
 420                                aat2870_devs[j].platform_data =
 421                                        pdata->subdevs[i].platform_data;
 422                                break;
 423                        }
 424                }
 425        }
 426
 427        ret = mfd_add_devices(aat2870->dev, 0, aat2870_devs,
 428                              ARRAY_SIZE(aat2870_devs), NULL, 0, NULL);
 429        if (ret != 0) {
 430                dev_err(aat2870->dev, "Failed to add subdev: %d\n", ret);
 431                goto out_disable;
 432        }
 433
 434        aat2870_init_debugfs(aat2870);
 435
 436        return 0;
 437
 438out_disable:
 439        aat2870_disable(aat2870);
 440        return ret;
 441}
 442
 443static int aat2870_i2c_remove(struct i2c_client *client)
 444{
 445        struct aat2870_data *aat2870 = i2c_get_clientdata(client);
 446
 447        aat2870_uninit_debugfs(aat2870);
 448
 449        mfd_remove_devices(aat2870->dev);
 450        aat2870_disable(aat2870);
 451        if (aat2870->uninit)
 452                aat2870->uninit(aat2870);
 453
 454        return 0;
 455}
 456
 457#ifdef CONFIG_PM_SLEEP
 458static int aat2870_i2c_suspend(struct device *dev)
 459{
 460        struct i2c_client *client = to_i2c_client(dev);
 461        struct aat2870_data *aat2870 = i2c_get_clientdata(client);
 462
 463        aat2870_disable(aat2870);
 464
 465        return 0;
 466}
 467
 468static int aat2870_i2c_resume(struct device *dev)
 469{
 470        struct i2c_client *client = to_i2c_client(dev);
 471        struct aat2870_data *aat2870 = i2c_get_clientdata(client);
 472        struct aat2870_register *reg = NULL;
 473        int i;
 474
 475        aat2870_enable(aat2870);
 476
 477        /* restore registers */
 478        for (i = 0; i < AAT2870_REG_NUM; i++) {
 479                reg = &aat2870->reg_cache[i];
 480                if (reg->writeable)
 481                        aat2870->write(aat2870, i, reg->value);
 482        }
 483
 484        return 0;
 485}
 486#endif /* CONFIG_PM_SLEEP */
 487
 488static SIMPLE_DEV_PM_OPS(aat2870_pm_ops, aat2870_i2c_suspend,
 489                         aat2870_i2c_resume);
 490
 491static const struct i2c_device_id aat2870_i2c_id_table[] = {
 492        { "aat2870", 0 },
 493        { }
 494};
 495MODULE_DEVICE_TABLE(i2c, aat2870_i2c_id_table);
 496
 497static struct i2c_driver aat2870_i2c_driver = {
 498        .driver = {
 499                .name   = "aat2870",
 500                .owner  = THIS_MODULE,
 501                .pm     = &aat2870_pm_ops,
 502        },
 503        .probe          = aat2870_i2c_probe,
 504        .remove         = aat2870_i2c_remove,
 505        .id_table       = aat2870_i2c_id_table,
 506};
 507
 508static int __init aat2870_init(void)
 509{
 510        return i2c_add_driver(&aat2870_i2c_driver);
 511}
 512subsys_initcall(aat2870_init);
 513
 514static void __exit aat2870_exit(void)
 515{
 516        i2c_del_driver(&aat2870_i2c_driver);
 517}
 518module_exit(aat2870_exit);
 519
 520MODULE_DESCRIPTION("Core support for the AnalogicTech AAT2870");
 521MODULE_LICENSE("GPL");
 522MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>");
 523
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