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        if (strict_strtoul(start, 16, &val))
 316                return -EINVAL;
 317
 318        ret = aat2870->write(aat2870, (u8)addr, (u8)val);
 319        if (ret)
 320                return ret;
 321
 322        return buf_size;
 323}
 324
 325static const struct file_operations aat2870_reg_fops = {
 326        .open = simple_open,
 327        .read = aat2870_reg_read_file,
 328        .write = aat2870_reg_write_file,
 329};
 330
 331static void aat2870_init_debugfs(struct aat2870_data *aat2870)
 332{
 333        aat2870->dentry_root = debugfs_create_dir("aat2870", NULL);
 334        if (!aat2870->dentry_root) {
 335                dev_warn(aat2870->dev,
 336                         "Failed to create debugfs root directory\n");
 337                return;
 338        }
 339
 340        aat2870->dentry_reg = debugfs_create_file("regs", 0644,
 341                                                  aat2870->dentry_root,
 342                                                  aat2870, &aat2870_reg_fops);
 343        if (!aat2870->dentry_reg)
 344                dev_warn(aat2870->dev,
 345                         "Failed to create debugfs register file\n");
 346}
 347
 348static void aat2870_uninit_debugfs(struct aat2870_data *aat2870)
 349{
 350        debugfs_remove_recursive(aat2870->dentry_root);
 351}
 352#else
 353static inline void aat2870_init_debugfs(struct aat2870_data *aat2870)
 354{
 355}
 356
 357static inline void aat2870_uninit_debugfs(struct aat2870_data *aat2870)
 358{
 359}
 360#endif /* CONFIG_DEBUG_FS */
 361
 362static int aat2870_i2c_probe(struct i2c_client *client,
 363                             const struct i2c_device_id *id)
 364{
 365        struct aat2870_platform_data *pdata = client->dev.platform_data;
 366        struct aat2870_data *aat2870;
 367        int i, j;
 368        int ret = 0;
 369
 370        aat2870 = kzalloc(sizeof(struct aat2870_data), GFP_KERNEL);
 371        if (!aat2870) {
 372                dev_err(&client->dev,
 373                        "Failed to allocate memory for aat2870\n");
 374                ret = -ENOMEM;
 375                goto out;
 376        }
 377
 378        aat2870->dev = &client->dev;
 379        dev_set_drvdata(aat2870->dev, aat2870);
 380
 381        aat2870->client = client;
 382        i2c_set_clientdata(client, aat2870);
 383
 384        aat2870->reg_cache = aat2870_regs;
 385
 386        if (pdata->en_pin < 0)
 387                aat2870->en_pin = -1;
 388        else
 389                aat2870->en_pin = pdata->en_pin;
 390
 391        aat2870->init = pdata->init;
 392        aat2870->uninit = pdata->uninit;
 393        aat2870->read = aat2870_read;
 394        aat2870->write = aat2870_write;
 395        aat2870->update = aat2870_update;
 396
 397        mutex_init(&aat2870->io_lock);
 398
 399        if (aat2870->init)
 400                aat2870->init(aat2870);
 401
 402        if (aat2870->en_pin >= 0) {
 403                ret = gpio_request_one(aat2870->en_pin, GPIOF_OUT_INIT_HIGH,
 404                                       "aat2870-en");
 405                if (ret < 0) {
 406                        dev_err(&client->dev,
 407                                "Failed to request GPIO %d\n", aat2870->en_pin);
 408                        goto out_kfree;
 409                }
 410        }
 411
 412        aat2870_enable(aat2870);
 413
 414        for (i = 0; i < pdata->num_subdevs; i++) {
 415                for (j = 0; j < ARRAY_SIZE(aat2870_devs); j++) {
 416                        if ((pdata->subdevs[i].id == aat2870_devs[j].id) &&
 417                                        !strcmp(pdata->subdevs[i].name,
 418                                                aat2870_devs[j].name)) {
 419                                aat2870_devs[j].platform_data =
 420                                        pdata->subdevs[i].platform_data;
 421                                break;
 422                        }
 423                }
 424        }
 425
 426        ret = mfd_add_devices(aat2870->dev, 0, aat2870_devs,
 427                              ARRAY_SIZE(aat2870_devs), NULL, 0, NULL);
 428        if (ret != 0) {
 429                dev_err(aat2870->dev, "Failed to add subdev: %d\n", ret);
 430                goto out_disable;
 431        }
 432
 433        aat2870_init_debugfs(aat2870);
 434
 435        return 0;
 436
 437out_disable:
 438        aat2870_disable(aat2870);
 439        if (aat2870->en_pin >= 0)
 440                gpio_free(aat2870->en_pin);
 441out_kfree:
 442        kfree(aat2870);
 443out:
 444        return ret;
 445}
 446
 447static int aat2870_i2c_remove(struct i2c_client *client)
 448{
 449        struct aat2870_data *aat2870 = i2c_get_clientdata(client);
 450
 451        aat2870_uninit_debugfs(aat2870);
 452
 453        mfd_remove_devices(aat2870->dev);
 454        aat2870_disable(aat2870);
 455        if (aat2870->en_pin >= 0)
 456                gpio_free(aat2870->en_pin);
 457        if (aat2870->uninit)
 458                aat2870->uninit(aat2870);
 459        kfree(aat2870);
 460
 461        return 0;
 462}
 463
 464#ifdef CONFIG_PM_SLEEP
 465static int aat2870_i2c_suspend(struct device *dev)
 466{
 467        struct i2c_client *client = to_i2c_client(dev);
 468        struct aat2870_data *aat2870 = i2c_get_clientdata(client);
 469
 470        aat2870_disable(aat2870);
 471
 472        return 0;
 473}
 474
 475static int aat2870_i2c_resume(struct device *dev)
 476{
 477        struct i2c_client *client = to_i2c_client(dev);
 478        struct aat2870_data *aat2870 = i2c_get_clientdata(client);
 479        struct aat2870_register *reg = NULL;
 480        int i;
 481
 482        aat2870_enable(aat2870);
 483
 484        /* restore registers */
 485        for (i = 0; i < AAT2870_REG_NUM; i++) {
 486                reg = &aat2870->reg_cache[i];
 487                if (reg->writeable)
 488                        aat2870->write(aat2870, i, reg->value);
 489        }
 490
 491        return 0;
 492}
 493#endif /* CONFIG_PM_SLEEP */
 494
 495static SIMPLE_DEV_PM_OPS(aat2870_pm_ops, aat2870_i2c_suspend,
 496                         aat2870_i2c_resume);
 497
 498static const struct i2c_device_id aat2870_i2c_id_table[] = {
 499        { "aat2870", 0 },
 500        { }
 501};
 502MODULE_DEVICE_TABLE(i2c, aat2870_i2c_id_table);
 503
 504static struct i2c_driver aat2870_i2c_driver = {
 505        .driver = {
 506                .name   = "aat2870",
 507                .owner  = THIS_MODULE,
 508                .pm     = &aat2870_pm_ops,
 509        },
 510        .probe          = aat2870_i2c_probe,
 511        .remove         = aat2870_i2c_remove,
 512        .id_table       = aat2870_i2c_id_table,
 513};
 514
 515static int __init aat2870_init(void)
 516{
 517        return i2c_add_driver(&aat2870_i2c_driver);
 518}
 519subsys_initcall(aat2870_init);
 520
 521static void __exit aat2870_exit(void)
 522{
 523        i2c_del_driver(&aat2870_i2c_driver);
 524}
 525module_exit(aat2870_exit);
 526
 527MODULE_DESCRIPTION("Core support for the AnalogicTech AAT2870");
 528MODULE_LICENSE("GPL");
 529MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>");
 530
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