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/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
  34 static 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
  77 static 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
 105 static 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
 131 out:
 132         dev_dbg(aat2870->dev, "read: addr=0x%02x, val=0x%02x\n", addr, *val);
 133         return 0;
 134 }
 135
 136 static 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
 166 static 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
 177 static 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
 188 static 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
 206 out_unlock:
 207         mutex_unlock(&aat2870->io_lock);
 208
 209         return ret;
 210 }
 211
 212 static 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
 220 static 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
 229 static 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
 264 static 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
 284 static 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
 328 static 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
 334 static 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
 352 static inline void aat2870_init_debugfs(struct aat2870_data *aat2870)
 353 {
 354 }
 355 #endif /* CONFIG_DEBUG_FS */
 356
 357 static 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
 429 out_disable:
 430         aat2870_disable(aat2870);
 431         return ret;
 432 }
 433
 434 #ifdef CONFIG_PM_SLEEP
 435 static 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
 445 static 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
 465 static SIMPLE_DEV_PM_OPS(aat2870_pm_ops, aat2870_i2c_suspend,
 466                          aat2870_i2c_resume);
 467
 468 static const struct i2c_device_id aat2870_i2c_id_table[] = {
 469         { "aat2870", 0 },
 470         { }
 471 };
 472
 473 static 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
 483 static int __init aat2870_init(void)
 484 {
 485         return i2c_add_driver(&aat2870_i2c_driver);
 486 }
 487 subsys_initcall(aat2870_init);