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         },
  83         {
  84                 .name = "aat2870-regulator",
  85                 .id = AAT2870_ID_LDOA,
  86         },
  87         {
  88                 .name = "aat2870-regulator",
  89                 .id = AAT2870_ID_LDOB,
  90         },
  91         {
  92                 .name = "aat2870-regulator",
  93                 .id = AAT2870_ID_LDOC,
  94         },
  95         {
  96                 .name = "aat2870-regulator",
  97                 .id = AAT2870_ID_LDOD,
  98         },
  99 };
 100
 101 static int __aat2870_read(struct aat2870_data *aat2870, u8 addr, u8 *val)
 102 {
 103         int ret;
 104
 105         if (addr >= AAT2870_REG_NUM) {
 106                 dev_err(aat2870->dev, "Invalid address, 0x%02x\n", addr);
 107                 return -EINVAL;
 108         }
 109
 110         if (!aat2870->reg_cache[addr].readable) {
 111                 *val = aat2870->reg_cache[addr].value;
 112                 goto out;
 113         }
 114
 115         ret = i2c_master_send(aat2870->client, &addr, 1);
 116         if (ret < 0)
 117                 return ret;
 118         if (ret != 1)
 119                 return -EIO;
 120
 121         ret = i2c_master_recv(aat2870->client, val, 1);
 122         if (ret < 0)
 123                 return ret;
 124         if (ret != 1)
 125                 return -EIO;
 126
 127 out:
 128         dev_dbg(aat2870->dev, "read: addr=0x%02x, val=0x%02x\n", addr, *val);
 129         return 0;
 130 }
 131
 132 static int __aat2870_write(struct aat2870_data *aat2870, u8 addr, u8 val)
 133 {
 134         u8 msg[2];
 135         int ret;
 136
 137         if (addr >= AAT2870_REG_NUM) {
 138                 dev_err(aat2870->dev, "Invalid address, 0x%02x\n", addr);
 139                 return -EINVAL;
 140         }
 141
 142         if (!aat2870->reg_cache[addr].writeable) {
 143                 dev_err(aat2870->dev, "Address 0x%02x is not writeable\n",
 144                         addr);
 145                 return -EINVAL;
 146         }
 147
 148         msg[0] = addr;
 149         msg[1] = val;
 150         ret = i2c_master_send(aat2870->client, msg, 2);
 151         if (ret < 0)
 152                 return ret;
 153         if (ret != 2)
 154                 return -EIO;
 155
 156         aat2870->reg_cache[addr].value = val;
 157
 158         dev_dbg(aat2870->dev, "write: addr=0x%02x, val=0x%02x\n", addr, val);
 159         return 0;
 160 }
 161
 162 static int aat2870_read(struct aat2870_data *aat2870, u8 addr, u8 *val)
 163 {
 164         int ret;
 165
 166         mutex_lock(&aat2870->io_lock);
 167         ret = __aat2870_read(aat2870, addr, val);
 168         mutex_unlock(&aat2870->io_lock);
 169
 170         return ret;
 171 }
 172
 173 static int aat2870_write(struct aat2870_data *aat2870, u8 addr, u8 val)
 174 {
 175         int ret;
 176
 177         mutex_lock(&aat2870->io_lock);
 178         ret = __aat2870_write(aat2870, addr, val);
 179         mutex_unlock(&aat2870->io_lock);
 180
 181         return ret;
 182 }
 183
 184 static int aat2870_update(struct aat2870_data *aat2870, u8 addr, u8 mask,
 185                           u8 val)
 186 {
 187         int change;
 188         u8 old_val, new_val;
 189         int ret;
 190
 191         mutex_lock(&aat2870->io_lock);
 192
 193         ret = __aat2870_read(aat2870, addr, &old_val);
 194         if (ret)
 195                 goto out_unlock;
 196
 197         new_val = (old_val & ~mask) | (val & mask);
 198         change = old_val != new_val;
 199         if (change)
 200                 ret = __aat2870_write(aat2870, addr, new_val);
 201
 202 out_unlock:
 203         mutex_unlock(&aat2870->io_lock);
 204
 205         return ret;
 206 }
 207
 208 static inline void aat2870_enable(struct aat2870_data *aat2870)
 209 {
 210         if (aat2870->en_pin >= 0)
 211                 gpio_set_value(aat2870->en_pin, 1);
 212
 213         aat2870->is_enable = 1;
 214 }
 215
 216 static inline void aat2870_disable(struct aat2870_data *aat2870)
 217 {
 218         if (aat2870->en_pin >= 0)
 219                 gpio_set_value(aat2870->en_pin, 0);
 220
 221         aat2870->is_enable = 0;
 222 }
 223
 224 #ifdef CONFIG_DEBUG_FS
 225 static ssize_t aat2870_dump_reg(struct aat2870_data *aat2870, char *buf)
 226 {
 227         u8 addr, val;
 228         ssize_t count = 0;
 229         int ret;
 230
 231         count += sprintf(buf, "aat2870 registers\n");
 232         for (addr = 0; addr < AAT2870_REG_NUM; addr++) {
 233                 count += sprintf(buf + count, "0x%02x: ", addr);
 234                 if (count >= PAGE_SIZE - 1)
 235                         break;
 236
 237                 ret = aat2870->read(aat2870, addr, &val);
 238                 if (ret == 0)
 239                         count += snprintf(buf + count, PAGE_SIZE - count,
 240                                           "0x%02x", val);
 241                 else
 242                         count += snprintf(buf + count, PAGE_SIZE - count,
 243                                           "<read fail: %d>", ret);
 244
 245                 if (count >= PAGE_SIZE - 1)
 246                         break;
 247
 248                 count += snprintf(buf + count, PAGE_SIZE - count, "\n");
 249                 if (count >= PAGE_SIZE - 1)
 250                         break;
 251         }
 252
 253         /* Truncate count; min() would cause a warning */
 254         if (count >= PAGE_SIZE)
 255                 count = PAGE_SIZE - 1;
 256
 257         return count;
 258 }
 259
 260 static int aat2870_reg_open_file(struct inode *inode, struct file *file)
 261 {
 262         file->private_data = inode->i_private;
 263
 264         return 0;
 265 }
 266
 267 static ssize_t aat2870_reg_read_file(struct file *file, char __user *user_buf,
 268                                      size_t count, loff_t *ppos)
 269 {
 270         struct aat2870_data *aat2870 = file->private_data;
 271         char *buf;
 272         ssize_t ret;
 273
 274         buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 275         if (!buf)
 276                 return -ENOMEM;
 277
 278         ret = aat2870_dump_reg(aat2870, buf);
 279         if (ret >= 0)
 280                 ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
 281
 282         kfree(buf);
 283
 284         return ret;
 285 }
 286
 287 static ssize_t aat2870_reg_write_file(struct file *file,
 288                                       const char __user *user_buf, size_t count,
 289                                       loff_t *ppos)
 290 {
 291         struct aat2870_data *aat2870 = file->private_data;
 292         char buf[32];
 293         int buf_size;
 294         char *start = buf;
 295         unsigned long addr, val;
 296         int ret;
 297
 298         buf_size = min(count, (sizeof(buf)-1));
 299         if (copy_from_user(buf, user_buf, buf_size)) {
 300                 dev_err(aat2870->dev, "Failed to copy from user\n");
 301                 return -EFAULT;
 302         }
 303         buf[buf_size] = 0;
 304
 305         while (*start == ' ')
 306                 start++;
 307
 308         addr = simple_strtoul(start, &start, 16);
 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         if (strict_strtoul(start, 16, &val))
 318                 return -EINVAL;
 319
 320         ret = aat2870->write(aat2870, (u8)addr, (u8)val);
 321         if (ret)
 322                 return ret;
 323
 324         return buf_size;
 325 }
 326
 327 static const struct file_operations aat2870_reg_fops = {
 328         .open = aat2870_reg_open_file,
 329         .read = aat2870_reg_read_file,
 330         .write = aat2870_reg_write_file,
 331 };
 332
 333 static void aat2870_init_debugfs(struct aat2870_data *aat2870)
 334 {
 335         aat2870->dentry_root = debugfs_create_dir("aat2870", NULL);
 336         if (!aat2870->dentry_root) {
 337                 dev_warn(aat2870->dev,
 338                          "Failed to create debugfs root directory\n");
 339                 return;
 340         }
 341
 342         aat2870->dentry_reg = debugfs_create_file("regs", 0644,
 343                                                   aat2870->dentry_root,
 344                                                   aat2870, &aat2870_reg_fops);
 345         if (!aat2870->dentry_reg)
 346                 dev_warn(aat2870->dev,
 347                          "Failed to create debugfs register file\n");
 348 }
 349
 350 static void aat2870_uninit_debugfs(struct aat2870_data *aat2870)
 351 {
 352         debugfs_remove_recursive(aat2870->dentry_root);
 353 }
 354 #else
 355 static inline void aat2870_init_debugfs(struct aat2870_data *aat2870)
 356 {
 357 }
 358
 359 static inline void aat2870_uninit_debugfs(struct aat2870_data *aat2870)
 360 {
 361 }
 362 #endif /* CONFIG_DEBUG_FS */
 363
 364 static int aat2870_i2c_probe(struct i2c_client *client,
 365                              const struct i2c_device_id *id)
 366 {
 367         struct aat2870_platform_data *pdata = client->dev.platform_data;
 368         struct aat2870_data *aat2870;
 369         int i, j;
 370         int ret = 0;
 371
 372         aat2870 = kzalloc(sizeof(struct aat2870_data), GFP_KERNEL);
 373         if (!aat2870) {
 374                 dev_err(&client->dev,
 375                         "Failed to allocate memory for aat2870\n");
 376                 ret = -ENOMEM;
 377                 goto out;
 378         }
 379
 380         aat2870->dev = &client->dev;
 381         dev_set_drvdata(aat2870->dev, aat2870);
 382
 383         aat2870->client = client;
 384         i2c_set_clientdata(client, aat2870);
 385
 386         aat2870->reg_cache = aat2870_regs;
 387
 388         if (pdata->en_pin < 0)
 389                 aat2870->en_pin = -1;
 390         else
 391                 aat2870->en_pin = pdata->en_pin;
 392
 393         aat2870->init = pdata->init;
 394         aat2870->uninit = pdata->uninit;
 395         aat2870->read = aat2870_read;
 396         aat2870->write = aat2870_write;
 397         aat2870->update = aat2870_update;
 398
 399         mutex_init(&aat2870->io_lock);
 400
 401         if (aat2870->init)
 402                 aat2870->init(aat2870);
 403
 404         if (aat2870->en_pin >= 0) {
 405                 ret = gpio_request(aat2870->en_pin, "aat2870-en");
 406                 if (ret < 0) {
 407                         dev_err(&client->dev,
 408                                 "Failed to request GPIO %d\n", aat2870->en_pin);
 409                         goto out_kfree;
 410                 }
 411                 gpio_direction_output(aat2870->en_pin, 1);
 412         }
 413
 414         aat2870_enable(aat2870);
 415
 416         for (i = 0; i < pdata->num_subdevs; i++) {
 417                 for (j = 0; j < ARRAY_SIZE(aat2870_devs); j++) {
 418                         if ((pdata->subdevs[i].id == aat2870_devs[j].id) &&
 419                                         !strcmp(pdata->subdevs[i].name,
 420                                                 aat2870_devs[j].name)) {
 421                                 aat2870_devs[j].mfd_data =
 422                                         pdata->subdevs[i].platform_data;
 423                                 break;
 424                         }
 425                 }
 426         }
 427
 428         ret = mfd_add_devices(aat2870->dev, 0, aat2870_devs,
 429                               ARRAY_SIZE(aat2870_devs), NULL, 0);
 430         if (ret != 0) {
 431                 dev_err(aat2870->dev, "Failed to add subdev: %d\n", ret);
 432                 goto out_disable;
 433         }
 434
 435         aat2870_init_debugfs(aat2870);
 436
 437         return 0;
 438
 439 out_disable:
 440         aat2870_disable(aat2870);
 441         if (aat2870->en_pin >= 0)
 442                 gpio_free(aat2870->en_pin);
 443 out_kfree:
 444         kfree(aat2870);
 445 out:
 446         return ret;
 447 }
 448
 449 static int aat2870_i2c_remove(struct i2c_client *client)
 450 {
 451         struct aat2870_data *aat2870 = i2c_get_clientdata(client);
 452
 453         aat2870_uninit_debugfs(aat2870);
 454
 455         mfd_remove_devices(aat2870->dev);
 456         aat2870_disable(aat2870);
 457         if (aat2870->en_pin >= 0)
 458                 gpio_free(aat2870->en_pin);
 459         if (aat2870->uninit)
 460                 aat2870->uninit(aat2870);
 461         kfree(aat2870);
 462
 463         return 0;
 464 }
 465
 466 #ifdef CONFIG_PM
 467 static int aat2870_i2c_suspend(struct i2c_client *client, pm_message_t state)
 468 {
 469         struct aat2870_data *aat2870 = i2c_get_clientdata(client);
 470
 471         aat2870_disable(aat2870);
 472
 473         return 0;
 474 }
 475
 476 static int aat2870_i2c_resume(struct i2c_client *client)
 477 {
 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 #else
 494 #define aat2870_i2c_suspend     NULL
 495 #define aat2870_i2c_resume      NULL
 496 #endif /* CONFIG_PM */
 497
 498 static struct i2c_device_id aat2870_i2c_id_table[] = {
 499         { "aat2870", 0 },
 500         { }
 501 };
 502 MODULE_DEVICE_TABLE(i2c, aat2870_i2c_id_table);
 503
 504 static struct i2c_driver aat2870_i2c_driver = {
 505         .driver = {
 506                 .name   = "aat2870",
 507                 .owner  = THIS_MODULE,
 508         },
 509         .probe          = aat2870_i2c_probe,
 510         .remove         = aat2870_i2c_remove,
 511         .suspend        = aat2870_i2c_suspend,
 512         .resume         = aat2870_i2c_resume,
 513         .id_table       = aat2870_i2c_id_table,
 514 };
 515
 516 static int __init aat2870_init(void)
 517 {
 518         return i2c_add_driver(&aat2870_i2c_driver);
 519 }
 520 subsys_initcall(aat2870_init);
 521
 522 static void __exit aat2870_exit(void)
 523 {
 524         i2c_del_driver(&aat2870_i2c_driver);
 525 }
 526 module_exit(aat2870_exit);
 527
 528 MODULE_DESCRIPTION("Core support for the AnalogicTech AAT2870");
 529 MODULE_LICENSE("GPL");
 530 MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>");