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