drivers/mfd/aat2870-core.c

   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
  35 static 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
  78 static 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
 106 static 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
 132 out:
 133         dev_dbg(aat2870->dev, "read: addr=0x%02x, val=0x%02x\n", addr, *val);
 134         return 0;
 135 }
 136
 137 static 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
 167 static 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
 178 static 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
 189 static 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
 207 out_unlock:
 208         mutex_unlock(&aat2870->io_lock);
 209
 210         return ret;
 211 }
 212
 213 static 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
 221 static 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
 230 static 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
 265 static int aat2870_reg_open_file(struct inode *inode, struct file *file)
 266 {
 267         file->private_data = inode->i_private;
 268
 269         return 0;
 270 }
 271
 272 static ssize_t aat2870_reg_read_file(struct file *file, char __user *user_buf,
 273                                      size_t count, loff_t *ppos)
 274 {
 275         struct aat2870_data *aat2870 = file->private_data;
 276         char *buf;
 277         ssize_t ret;
 278
 279         buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 280         if (!buf)
 281                 return -ENOMEM;
 282
 283         ret = aat2870_dump_reg(aat2870, buf);
 284         if (ret >= 0)
 285                 ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
 286
 287         kfree(buf);
 288
 289         return ret;
 290 }
 291
 292 static ssize_t aat2870_reg_write_file(struct file *file,
 293                                       const char __user *user_buf, size_t count,
 294                                       loff_t *ppos)
 295 {
 296         struct aat2870_data *aat2870 = file->private_data;
 297         char buf[32];
 298         ssize_t buf_size;
 299         char *start = buf;
 300         unsigned long addr, val;
 301         int ret;
 302
 303         buf_size = min(count, (sizeof(buf)-1));
 304         if (copy_from_user(buf, user_buf, buf_size)) {
 305                 dev_err(aat2870->dev, "Failed to copy from user\n");
 306                 return -EFAULT;
 307         }
 308         buf[buf_size] = 0;
 309
 310         while (*start == ' ')
 311                 start++;
 312
 313         addr = simple_strtoul(start, &start, 16);
 314         if (addr >= AAT2870_REG_NUM) {
 315                 dev_err(aat2870->dev, "Invalid address, 0x%lx\n", addr);
 316                 return -EINVAL;
 317         }
 318
 319         while (*start == ' ')
 320                 start++;
 321
 322         if (strict_strtoul(start, 16, &val))
 323                 return -EINVAL;
 324
 325         ret = aat2870->write(aat2870, (u8)addr, (u8)val);
 326         if (ret)
 327                 return ret;
 328
 329         return buf_size;
 330 }
 331
 332 static const struct file_operations aat2870_reg_fops = {
 333         .open = aat2870_reg_open_file,
 334         .read = aat2870_reg_read_file,
 335         .write = aat2870_reg_write_file,
 336 };
 337
 338 static void aat2870_init_debugfs(struct aat2870_data *aat2870)
 339 {
 340         aat2870->dentry_root = debugfs_create_dir("aat2870", NULL);
 341         if (!aat2870->dentry_root) {
 342                 dev_warn(aat2870->dev,
 343                          "Failed to create debugfs root directory\n");
 344                 return;
 345         }
 346
 347         aat2870->dentry_reg = debugfs_create_file("regs", 0644,
 348                                                   aat2870->dentry_root,
 349                                                   aat2870, &aat2870_reg_fops);
 350         if (!aat2870->dentry_reg)
 351                 dev_warn(aat2870->dev,
 352                          "Failed to create debugfs register file\n");
 353 }
 354
 355 static void aat2870_uninit_debugfs(struct aat2870_data *aat2870)
 356 {
 357         debugfs_remove_recursive(aat2870->dentry_root);
 358 }
 359 #else
 360 static inline void aat2870_init_debugfs(struct aat2870_data *aat2870)
 361 {
 362 }
 363
 364 static inline void aat2870_uninit_debugfs(struct aat2870_data *aat2870)
 365 {
 366 }
 367 #endif /* CONFIG_DEBUG_FS */
 368
 369 static int aat2870_i2c_probe(struct i2c_client *client,
 370                              const struct i2c_device_id *id)
 371 {
 372         struct aat2870_platform_data *pdata = client->dev.platform_data;
 373         struct aat2870_data *aat2870;
 374         int i, j;
 375         int ret = 0;
 376
 377         aat2870 = kzalloc(sizeof(struct aat2870_data), GFP_KERNEL);
 378         if (!aat2870) {
 379                 dev_err(&client->dev,
 380                         "Failed to allocate memory for aat2870\n");
 381                 ret = -ENOMEM;
 382                 goto out;
 383         }
 384
 385         aat2870->dev = &client->dev;
 386         dev_set_drvdata(aat2870->dev, aat2870);
 387
 388         aat2870->client = client;
 389         i2c_set_clientdata(client, aat2870);
 390
 391         aat2870->reg_cache = aat2870_regs;
 392
 393         if (pdata->en_pin < 0)
 394                 aat2870->en_pin = -1;
 395         else
 396                 aat2870->en_pin = pdata->en_pin;
 397
 398         aat2870->init = pdata->init;
 399         aat2870->uninit = pdata->uninit;
 400         aat2870->read = aat2870_read;
 401         aat2870->write = aat2870_write;
 402         aat2870->update = aat2870_update;
 403
 404         mutex_init(&aat2870->io_lock);
 405
 406         if (aat2870->init)
 407                 aat2870->init(aat2870);
 408
 409         if (aat2870->en_pin >= 0) {
 410                 ret = gpio_request(aat2870->en_pin, "aat2870-en");
 411                 if (ret < 0) {
 412                         dev_err(&client->dev,
 413                                 "Failed to request GPIO %d\n", aat2870->en_pin);
 414                         goto out_kfree;
 415                 }
 416                 gpio_direction_output(aat2870->en_pin, 1);
 417         }
 418
 419         aat2870_enable(aat2870);
 420
 421         for (i = 0; i < pdata->num_subdevs; i++) {
 422                 for (j = 0; j < ARRAY_SIZE(aat2870_devs); j++) {
 423                         if ((pdata->subdevs[i].id == aat2870_devs[j].id) &&
 424                                         !strcmp(pdata->subdevs[i].name,
 425                                                 aat2870_devs[j].name)) {
 426                                 aat2870_devs[j].platform_data =
 427                                         pdata->subdevs[i].platform_data;
 428                                 break;
 429                         }
 430                 }
 431         }
 432
 433         ret = mfd_add_devices(aat2870->dev, 0, aat2870_devs,
 434                               ARRAY_SIZE(aat2870_devs), NULL, 0);
 435         if (ret != 0) {
 436                 dev_err(aat2870->dev, "Failed to add subdev: %d\n", ret);
 437                 goto out_disable;
 438         }
 439
 440         aat2870_init_debugfs(aat2870);
 441
 442         return 0;
 443
 444 out_disable:
 445         aat2870_disable(aat2870);
 446         if (aat2870->en_pin >= 0)
 447                 gpio_free(aat2870->en_pin);
 448 out_kfree:
 449         kfree(aat2870);
 450 out:
 451         return ret;
 452 }
 453
 454 static int aat2870_i2c_remove(struct i2c_client *client)
 455 {
 456         struct aat2870_data *aat2870 = i2c_get_clientdata(client);
 457
 458         aat2870_uninit_debugfs(aat2870);
 459
 460         mfd_remove_devices(aat2870->dev);
 461         aat2870_disable(aat2870);
 462         if (aat2870->en_pin >= 0)
 463                 gpio_free(aat2870->en_pin);
 464         if (aat2870->uninit)
 465                 aat2870->uninit(aat2870);
 466         kfree(aat2870);
 467
 468         return 0;
 469 }
 470
 471 #ifdef CONFIG_PM
 472 static int aat2870_i2c_suspend(struct i2c_client *client, pm_message_t state)
 473 {
 474         struct aat2870_data *aat2870 = i2c_get_clientdata(client);
 475
 476         aat2870_disable(aat2870);
 477
 478         return 0;
 479 }
 480
 481 static int aat2870_i2c_resume(struct i2c_client *client)
 482 {
 483         struct aat2870_data *aat2870 = i2c_get_clientdata(client);
 484         struct aat2870_register *reg = NULL;
 485         int i;
 486
 487         aat2870_enable(aat2870);
 488
 489         /* restore registers */
 490         for (i = 0; i < AAT2870_REG_NUM; i++) {
 491                 reg = &aat2870->reg_cache[i];
 492                 if (reg->writeable)
 493                         aat2870->write(aat2870, i, reg->value);
 494         }
 495
 496         return 0;
 497 }
 498 #else
 499 #define aat2870_i2c_suspend     NULL
 500 #define aat2870_i2c_resume      NULL
 501 #endif /* CONFIG_PM */
 502
 503 static struct i2c_device_id aat2870_i2c_id_table[] = {
 504         { "aat2870", 0 },
 505         { }
 506 };
 507 MODULE_DEVICE_TABLE(i2c, aat2870_i2c_id_table);
 508
 509 static struct i2c_driver aat2870_i2c_driver = {
 510         .driver = {
 511                 .name   = "aat2870",
 512                 .owner  = THIS_MODULE,
 513         },
 514         .probe          = aat2870_i2c_probe,
 515         .remove         = aat2870_i2c_remove,
 516         .suspend        = aat2870_i2c_suspend,
 517         .resume         = aat2870_i2c_resume,
 518         .id_table       = aat2870_i2c_id_table,
 519 };
 520
 521 static int __init aat2870_init(void)
 522 {
 523         return i2c_add_driver(&aat2870_i2c_driver);
 524 }
 525 subsys_initcall(aat2870_init);
 526
 527 static void __exit aat2870_exit(void)
 528 {
 529         i2c_del_driver(&aat2870_i2c_driver);
 530 }
 531 module_exit(aat2870_exit);
 532
 533 MODULE_DESCRIPTION("Core support for the AnalogicTech AAT2870");
 534 MODULE_LICENSE("GPL");
 535 MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>");