Daniel Mack | 3cdbbee | 2009-03-31 15:23:53 -0700 | [diff] [blame] | 1 | /* |
| 2 | * isl29003.c - Linux kernel module for |
| 3 | * Intersil ISL29003 ambient light sensor |
| 4 | * |
| 5 | * See file:Documentation/misc-devices/isl29003 |
| 6 | * |
| 7 | * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de> |
| 8 | * |
| 9 | * Based on code written by |
| 10 | * Rodolfo Giometti <giometti@linux.it> |
| 11 | * Eurotech S.p.A. <info@eurotech.it> |
| 12 | * |
| 13 | * This program is free software; you can redistribute it and/or modify |
| 14 | * it under the terms of the GNU General Public License as published by |
| 15 | * the Free Software Foundation; either version 2 of the License, or |
| 16 | * (at your option) any later version. |
| 17 | * |
| 18 | * This program is distributed in the hope that it will be useful, |
| 19 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 20 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 21 | * GNU General Public License for more details. |
| 22 | * |
| 23 | * You should have received a copy of the GNU General Public License |
| 24 | * along with this program; if not, write to the Free Software |
| 25 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 26 | */ |
| 27 | |
| 28 | #include <linux/module.h> |
| 29 | #include <linux/init.h> |
| 30 | #include <linux/slab.h> |
| 31 | #include <linux/i2c.h> |
| 32 | #include <linux/mutex.h> |
| 33 | #include <linux/delay.h> |
| 34 | |
| 35 | #define ISL29003_DRV_NAME "isl29003" |
| 36 | #define DRIVER_VERSION "1.0" |
| 37 | |
| 38 | #define ISL29003_REG_COMMAND 0x00 |
| 39 | #define ISL29003_ADC_ENABLED (1 << 7) |
| 40 | #define ISL29003_ADC_PD (1 << 6) |
| 41 | #define ISL29003_TIMING_INT (1 << 5) |
| 42 | #define ISL29003_MODE_SHIFT (2) |
| 43 | #define ISL29003_MODE_MASK (0x3 << ISL29003_MODE_SHIFT) |
| 44 | #define ISL29003_RES_SHIFT (0) |
| 45 | #define ISL29003_RES_MASK (0x3 << ISL29003_RES_SHIFT) |
| 46 | |
| 47 | #define ISL29003_REG_CONTROL 0x01 |
| 48 | #define ISL29003_INT_FLG (1 << 5) |
| 49 | #define ISL29003_RANGE_SHIFT (2) |
| 50 | #define ISL29003_RANGE_MASK (0x3 << ISL29003_RANGE_SHIFT) |
| 51 | #define ISL29003_INT_PERSISTS_SHIFT (0) |
| 52 | #define ISL29003_INT_PERSISTS_MASK (0xf << ISL29003_INT_PERSISTS_SHIFT) |
| 53 | |
| 54 | #define ISL29003_REG_IRQ_THRESH_HI 0x02 |
| 55 | #define ISL29003_REG_IRQ_THRESH_LO 0x03 |
| 56 | #define ISL29003_REG_LSB_SENSOR 0x04 |
| 57 | #define ISL29003_REG_MSB_SENSOR 0x05 |
| 58 | #define ISL29003_REG_LSB_TIMER 0x06 |
| 59 | #define ISL29003_REG_MSB_TIMER 0x07 |
| 60 | |
| 61 | #define ISL29003_NUM_CACHABLE_REGS 4 |
| 62 | |
| 63 | struct isl29003_data { |
| 64 | struct i2c_client *client; |
| 65 | struct mutex lock; |
| 66 | u8 reg_cache[ISL29003_NUM_CACHABLE_REGS]; |
Daniel Mack | 74614f8 | 2009-05-06 16:03:00 -0700 | [diff] [blame] | 67 | u8 power_state_before_suspend; |
Daniel Mack | 3cdbbee | 2009-03-31 15:23:53 -0700 | [diff] [blame] | 68 | }; |
| 69 | |
| 70 | static int gain_range[] = { |
| 71 | 1000, 4000, 16000, 64000 |
| 72 | }; |
| 73 | |
| 74 | /* |
| 75 | * register access helpers |
| 76 | */ |
| 77 | |
| 78 | static int __isl29003_read_reg(struct i2c_client *client, |
| 79 | u32 reg, u8 mask, u8 shift) |
| 80 | { |
| 81 | struct isl29003_data *data = i2c_get_clientdata(client); |
| 82 | return (data->reg_cache[reg] & mask) >> shift; |
| 83 | } |
| 84 | |
| 85 | static int __isl29003_write_reg(struct i2c_client *client, |
| 86 | u32 reg, u8 mask, u8 shift, u8 val) |
| 87 | { |
| 88 | struct isl29003_data *data = i2c_get_clientdata(client); |
| 89 | int ret = 0; |
| 90 | u8 tmp; |
| 91 | |
| 92 | if (reg >= ISL29003_NUM_CACHABLE_REGS) |
| 93 | return -EINVAL; |
| 94 | |
| 95 | mutex_lock(&data->lock); |
| 96 | |
| 97 | tmp = data->reg_cache[reg]; |
| 98 | tmp &= ~mask; |
| 99 | tmp |= val << shift; |
| 100 | |
| 101 | ret = i2c_smbus_write_byte_data(client, reg, tmp); |
| 102 | if (!ret) |
| 103 | data->reg_cache[reg] = tmp; |
| 104 | |
| 105 | mutex_unlock(&data->lock); |
| 106 | return ret; |
| 107 | } |
| 108 | |
| 109 | /* |
| 110 | * internally used functions |
| 111 | */ |
| 112 | |
| 113 | /* range */ |
| 114 | static int isl29003_get_range(struct i2c_client *client) |
| 115 | { |
| 116 | return __isl29003_read_reg(client, ISL29003_REG_CONTROL, |
| 117 | ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT); |
| 118 | } |
| 119 | |
| 120 | static int isl29003_set_range(struct i2c_client *client, int range) |
| 121 | { |
| 122 | return __isl29003_write_reg(client, ISL29003_REG_CONTROL, |
| 123 | ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT, range); |
| 124 | } |
| 125 | |
| 126 | /* resolution */ |
| 127 | static int isl29003_get_resolution(struct i2c_client *client) |
| 128 | { |
| 129 | return __isl29003_read_reg(client, ISL29003_REG_COMMAND, |
| 130 | ISL29003_RES_MASK, ISL29003_RES_SHIFT); |
| 131 | } |
| 132 | |
| 133 | static int isl29003_set_resolution(struct i2c_client *client, int res) |
| 134 | { |
| 135 | return __isl29003_write_reg(client, ISL29003_REG_COMMAND, |
| 136 | ISL29003_RES_MASK, ISL29003_RES_SHIFT, res); |
| 137 | } |
| 138 | |
| 139 | /* mode */ |
| 140 | static int isl29003_get_mode(struct i2c_client *client) |
| 141 | { |
| 142 | return __isl29003_read_reg(client, ISL29003_REG_COMMAND, |
| 143 | ISL29003_RES_MASK, ISL29003_RES_SHIFT); |
| 144 | } |
| 145 | |
| 146 | static int isl29003_set_mode(struct i2c_client *client, int mode) |
| 147 | { |
| 148 | return __isl29003_write_reg(client, ISL29003_REG_COMMAND, |
| 149 | ISL29003_RES_MASK, ISL29003_RES_SHIFT, mode); |
| 150 | } |
| 151 | |
| 152 | /* power_state */ |
| 153 | static int isl29003_set_power_state(struct i2c_client *client, int state) |
| 154 | { |
| 155 | return __isl29003_write_reg(client, ISL29003_REG_COMMAND, |
| 156 | ISL29003_ADC_ENABLED | ISL29003_ADC_PD, 0, |
| 157 | state ? ISL29003_ADC_ENABLED : ISL29003_ADC_PD); |
| 158 | } |
| 159 | |
| 160 | static int isl29003_get_power_state(struct i2c_client *client) |
| 161 | { |
| 162 | struct isl29003_data *data = i2c_get_clientdata(client); |
| 163 | u8 cmdreg = data->reg_cache[ISL29003_REG_COMMAND]; |
| 164 | return ~cmdreg & ISL29003_ADC_PD; |
| 165 | } |
| 166 | |
| 167 | static int isl29003_get_adc_value(struct i2c_client *client) |
| 168 | { |
| 169 | struct isl29003_data *data = i2c_get_clientdata(client); |
| 170 | int lsb, msb, range, bitdepth; |
| 171 | |
| 172 | mutex_lock(&data->lock); |
| 173 | lsb = i2c_smbus_read_byte_data(client, ISL29003_REG_LSB_SENSOR); |
| 174 | |
| 175 | if (lsb < 0) { |
| 176 | mutex_unlock(&data->lock); |
| 177 | return lsb; |
| 178 | } |
| 179 | |
| 180 | msb = i2c_smbus_read_byte_data(client, ISL29003_REG_MSB_SENSOR); |
| 181 | mutex_unlock(&data->lock); |
| 182 | |
| 183 | if (msb < 0) |
| 184 | return msb; |
| 185 | |
| 186 | range = isl29003_get_range(client); |
| 187 | bitdepth = (4 - isl29003_get_resolution(client)) * 4; |
| 188 | return (((msb << 8) | lsb) * gain_range[range]) >> bitdepth; |
| 189 | } |
| 190 | |
| 191 | /* |
| 192 | * sysfs layer |
| 193 | */ |
| 194 | |
| 195 | /* range */ |
| 196 | static ssize_t isl29003_show_range(struct device *dev, |
| 197 | struct device_attribute *attr, char *buf) |
| 198 | { |
| 199 | struct i2c_client *client = to_i2c_client(dev); |
| 200 | return sprintf(buf, "%i\n", isl29003_get_range(client)); |
| 201 | } |
| 202 | |
| 203 | static ssize_t isl29003_store_range(struct device *dev, |
| 204 | struct device_attribute *attr, |
| 205 | const char *buf, size_t count) |
| 206 | { |
| 207 | struct i2c_client *client = to_i2c_client(dev); |
| 208 | unsigned long val; |
| 209 | int ret; |
| 210 | |
| 211 | if ((strict_strtoul(buf, 10, &val) < 0) || (val > 3)) |
| 212 | return -EINVAL; |
| 213 | |
| 214 | ret = isl29003_set_range(client, val); |
| 215 | if (ret < 0) |
| 216 | return ret; |
| 217 | |
| 218 | return count; |
| 219 | } |
| 220 | |
| 221 | static DEVICE_ATTR(range, S_IWUSR | S_IRUGO, |
| 222 | isl29003_show_range, isl29003_store_range); |
| 223 | |
| 224 | |
| 225 | /* resolution */ |
| 226 | static ssize_t isl29003_show_resolution(struct device *dev, |
| 227 | struct device_attribute *attr, |
| 228 | char *buf) |
| 229 | { |
| 230 | struct i2c_client *client = to_i2c_client(dev); |
| 231 | return sprintf(buf, "%d\n", isl29003_get_resolution(client)); |
| 232 | } |
| 233 | |
| 234 | static ssize_t isl29003_store_resolution(struct device *dev, |
| 235 | struct device_attribute *attr, |
| 236 | const char *buf, size_t count) |
| 237 | { |
| 238 | struct i2c_client *client = to_i2c_client(dev); |
| 239 | unsigned long val; |
| 240 | int ret; |
| 241 | |
| 242 | if ((strict_strtoul(buf, 10, &val) < 0) || (val > 3)) |
| 243 | return -EINVAL; |
| 244 | |
| 245 | ret = isl29003_set_resolution(client, val); |
| 246 | if (ret < 0) |
| 247 | return ret; |
| 248 | |
| 249 | return count; |
| 250 | } |
| 251 | |
| 252 | static DEVICE_ATTR(resolution, S_IWUSR | S_IRUGO, |
| 253 | isl29003_show_resolution, isl29003_store_resolution); |
| 254 | |
| 255 | /* mode */ |
| 256 | static ssize_t isl29003_show_mode(struct device *dev, |
| 257 | struct device_attribute *attr, char *buf) |
| 258 | { |
| 259 | struct i2c_client *client = to_i2c_client(dev); |
| 260 | return sprintf(buf, "%d\n", isl29003_get_mode(client)); |
| 261 | } |
| 262 | |
| 263 | static ssize_t isl29003_store_mode(struct device *dev, |
| 264 | struct device_attribute *attr, const char *buf, size_t count) |
| 265 | { |
| 266 | struct i2c_client *client = to_i2c_client(dev); |
| 267 | unsigned long val; |
| 268 | int ret; |
| 269 | |
| 270 | if ((strict_strtoul(buf, 10, &val) < 0) || (val > 2)) |
| 271 | return -EINVAL; |
| 272 | |
| 273 | ret = isl29003_set_mode(client, val); |
| 274 | if (ret < 0) |
| 275 | return ret; |
| 276 | |
| 277 | return count; |
| 278 | } |
| 279 | |
| 280 | static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO, |
| 281 | isl29003_show_mode, isl29003_store_mode); |
| 282 | |
| 283 | |
| 284 | /* power state */ |
| 285 | static ssize_t isl29003_show_power_state(struct device *dev, |
| 286 | struct device_attribute *attr, |
| 287 | char *buf) |
| 288 | { |
| 289 | struct i2c_client *client = to_i2c_client(dev); |
| 290 | return sprintf(buf, "%d\n", isl29003_get_power_state(client)); |
| 291 | } |
| 292 | |
| 293 | static ssize_t isl29003_store_power_state(struct device *dev, |
| 294 | struct device_attribute *attr, |
| 295 | const char *buf, size_t count) |
| 296 | { |
| 297 | struct i2c_client *client = to_i2c_client(dev); |
| 298 | unsigned long val; |
| 299 | int ret; |
| 300 | |
| 301 | if ((strict_strtoul(buf, 10, &val) < 0) || (val > 1)) |
| 302 | return -EINVAL; |
| 303 | |
| 304 | ret = isl29003_set_power_state(client, val); |
| 305 | return ret ? ret : count; |
| 306 | } |
| 307 | |
| 308 | static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO, |
| 309 | isl29003_show_power_state, isl29003_store_power_state); |
| 310 | |
| 311 | |
| 312 | /* lux */ |
| 313 | static ssize_t isl29003_show_lux(struct device *dev, |
| 314 | struct device_attribute *attr, char *buf) |
| 315 | { |
| 316 | struct i2c_client *client = to_i2c_client(dev); |
| 317 | |
| 318 | /* No LUX data if not operational */ |
| 319 | if (!isl29003_get_power_state(client)) |
| 320 | return -EBUSY; |
| 321 | |
| 322 | return sprintf(buf, "%d\n", isl29003_get_adc_value(client)); |
| 323 | } |
| 324 | |
| 325 | static DEVICE_ATTR(lux, S_IRUGO, isl29003_show_lux, NULL); |
| 326 | |
| 327 | static struct attribute *isl29003_attributes[] = { |
| 328 | &dev_attr_range.attr, |
| 329 | &dev_attr_resolution.attr, |
| 330 | &dev_attr_mode.attr, |
| 331 | &dev_attr_power_state.attr, |
| 332 | &dev_attr_lux.attr, |
| 333 | NULL |
| 334 | }; |
| 335 | |
| 336 | static const struct attribute_group isl29003_attr_group = { |
| 337 | .attrs = isl29003_attributes, |
| 338 | }; |
| 339 | |
| 340 | static int isl29003_init_client(struct i2c_client *client) |
| 341 | { |
| 342 | struct isl29003_data *data = i2c_get_clientdata(client); |
| 343 | int i; |
| 344 | |
| 345 | /* read all the registers once to fill the cache. |
| 346 | * if one of the reads fails, we consider the init failed */ |
| 347 | for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++) { |
| 348 | int v = i2c_smbus_read_byte_data(client, i); |
| 349 | if (v < 0) |
| 350 | return -ENODEV; |
| 351 | |
| 352 | data->reg_cache[i] = v; |
| 353 | } |
| 354 | |
| 355 | /* set defaults */ |
| 356 | isl29003_set_range(client, 0); |
| 357 | isl29003_set_resolution(client, 0); |
| 358 | isl29003_set_mode(client, 0); |
| 359 | isl29003_set_power_state(client, 0); |
| 360 | |
| 361 | return 0; |
| 362 | } |
| 363 | |
| 364 | /* |
| 365 | * I2C layer |
| 366 | */ |
| 367 | |
Bill Pemberton | 80c8ae2 | 2012-11-19 13:23:05 -0500 | [diff] [blame] | 368 | static int isl29003_probe(struct i2c_client *client, |
Daniel Mack | 3cdbbee | 2009-03-31 15:23:53 -0700 | [diff] [blame] | 369 | const struct i2c_device_id *id) |
| 370 | { |
| 371 | struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); |
| 372 | struct isl29003_data *data; |
| 373 | int err = 0; |
| 374 | |
| 375 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) |
| 376 | return -EIO; |
| 377 | |
| 378 | data = kzalloc(sizeof(struct isl29003_data), GFP_KERNEL); |
| 379 | if (!data) |
| 380 | return -ENOMEM; |
| 381 | |
| 382 | data->client = client; |
| 383 | i2c_set_clientdata(client, data); |
| 384 | mutex_init(&data->lock); |
| 385 | |
| 386 | /* initialize the ISL29003 chip */ |
| 387 | err = isl29003_init_client(client); |
| 388 | if (err) |
| 389 | goto exit_kfree; |
| 390 | |
| 391 | /* register sysfs hooks */ |
| 392 | err = sysfs_create_group(&client->dev.kobj, &isl29003_attr_group); |
| 393 | if (err) |
| 394 | goto exit_kfree; |
| 395 | |
| 396 | dev_info(&client->dev, "driver version %s enabled\n", DRIVER_VERSION); |
| 397 | return 0; |
| 398 | |
| 399 | exit_kfree: |
| 400 | kfree(data); |
| 401 | return err; |
| 402 | } |
| 403 | |
Bill Pemberton | 486a5c2 | 2012-11-19 13:26:02 -0500 | [diff] [blame] | 404 | static int isl29003_remove(struct i2c_client *client) |
Daniel Mack | 3cdbbee | 2009-03-31 15:23:53 -0700 | [diff] [blame] | 405 | { |
| 406 | sysfs_remove_group(&client->dev.kobj, &isl29003_attr_group); |
| 407 | isl29003_set_power_state(client, 0); |
| 408 | kfree(i2c_get_clientdata(client)); |
| 409 | return 0; |
| 410 | } |
| 411 | |
| 412 | #ifdef CONFIG_PM |
| 413 | static int isl29003_suspend(struct i2c_client *client, pm_message_t mesg) |
| 414 | { |
Daniel Mack | 74614f8 | 2009-05-06 16:03:00 -0700 | [diff] [blame] | 415 | struct isl29003_data *data = i2c_get_clientdata(client); |
| 416 | |
| 417 | data->power_state_before_suspend = isl29003_get_power_state(client); |
Daniel Mack | 3cdbbee | 2009-03-31 15:23:53 -0700 | [diff] [blame] | 418 | return isl29003_set_power_state(client, 0); |
| 419 | } |
| 420 | |
| 421 | static int isl29003_resume(struct i2c_client *client) |
| 422 | { |
| 423 | int i; |
| 424 | struct isl29003_data *data = i2c_get_clientdata(client); |
| 425 | |
| 426 | /* restore registers from cache */ |
| 427 | for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++) |
Daniel Mack | 74614f8 | 2009-05-06 16:03:00 -0700 | [diff] [blame] | 428 | if (i2c_smbus_write_byte_data(client, i, data->reg_cache[i])) |
Daniel Mack | 3cdbbee | 2009-03-31 15:23:53 -0700 | [diff] [blame] | 429 | return -EIO; |
| 430 | |
Daniel Mack | 74614f8 | 2009-05-06 16:03:00 -0700 | [diff] [blame] | 431 | return isl29003_set_power_state(client, |
| 432 | data->power_state_before_suspend); |
Daniel Mack | 3cdbbee | 2009-03-31 15:23:53 -0700 | [diff] [blame] | 433 | } |
| 434 | |
| 435 | #else |
| 436 | #define isl29003_suspend NULL |
| 437 | #define isl29003_resume NULL |
| 438 | #endif /* CONFIG_PM */ |
| 439 | |
| 440 | static const struct i2c_device_id isl29003_id[] = { |
| 441 | { "isl29003", 0 }, |
| 442 | {} |
| 443 | }; |
| 444 | MODULE_DEVICE_TABLE(i2c, isl29003_id); |
| 445 | |
| 446 | static struct i2c_driver isl29003_driver = { |
| 447 | .driver = { |
| 448 | .name = ISL29003_DRV_NAME, |
| 449 | .owner = THIS_MODULE, |
| 450 | }, |
| 451 | .suspend = isl29003_suspend, |
| 452 | .resume = isl29003_resume, |
| 453 | .probe = isl29003_probe, |
Bill Pemberton | 2d6bed9 | 2012-11-19 13:21:23 -0500 | [diff] [blame] | 454 | .remove = isl29003_remove, |
Daniel Mack | 3cdbbee | 2009-03-31 15:23:53 -0700 | [diff] [blame] | 455 | .id_table = isl29003_id, |
| 456 | }; |
| 457 | |
Axel Lin | a64fe2e | 2012-01-22 15:36:45 +0800 | [diff] [blame] | 458 | module_i2c_driver(isl29003_driver); |
Daniel Mack | 3cdbbee | 2009-03-31 15:23:53 -0700 | [diff] [blame] | 459 | |
| 460 | MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>"); |
| 461 | MODULE_DESCRIPTION("ISL29003 ambient light sensor driver"); |
| 462 | MODULE_LICENSE("GPL v2"); |
| 463 | MODULE_VERSION(DRIVER_VERSION); |