drivers/leds/leds-pca9532.c

   1 /*
   2  * pca9532.c - 16-bit Led dimmer
   3  *
   4  * Copyright (C) 2011 Jan Weitzel
   5  * Copyright (C) 2008 Riku Voipio
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; version 2 of the License.
  10  *
  11  * Datasheet: http://www.nxp.com/documents/data_sheet/PCA9532.pdf
  12  *
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/i2c.h>
  17 #include <linux/slab.h>
  18 #include <linux/leds.h>
  19 #include <linux/input.h>
  20 #include <linux/mutex.h>
  21 #include <linux/workqueue.h>
  22 #include <linux/leds-pca9532.h>
  23 #include <linux/gpio.h>
  24 #include <linux/of.h>
  25 #include <linux/of_device.h>
  26
  27 /* m =  num_leds*/
  28 #define PCA9532_REG_INPUT(i)    ((i) >> 3)
  29 #define PCA9532_REG_OFFSET(m)   ((m) >> 4)
  30 #define PCA9532_REG_PSC(m, i)   (PCA9532_REG_OFFSET(m) + 0x1 + (i) * 2)
  31 #define PCA9532_REG_PWM(m, i)   (PCA9532_REG_OFFSET(m) + 0x2 + (i) * 2)
  32 #define LED_REG(m, led)         (PCA9532_REG_OFFSET(m) + 0x5 + (led >> 2))
  33 #define LED_NUM(led)            (led & 0x3)
  34
  35 #define ldev_to_led(c)       container_of(c, struct pca9532_led, ldev)
  36
  37 struct pca9532_chip_info {
  38         u8      num_leds;
  39 };
  40
  41 struct pca9532_data {
  42         struct i2c_client *client;
  43         struct pca9532_led leds[16];
  44         struct mutex update_lock;
  45         struct input_dev *idev;
  46         struct work_struct work;
  47 #ifdef CONFIG_LEDS_PCA9532_GPIO
  48         struct gpio_chip gpio;
  49 #endif
  50         const struct pca9532_chip_info *chip_info;
  51         u8 pwm[2];
  52         u8 psc[2];
  53 };
  54
  55 static int pca9532_probe(struct i2c_client *client,
  56         const struct i2c_device_id *id);
  57 static int pca9532_remove(struct i2c_client *client);
  58
  59 enum {
  60         pca9530,
  61         pca9531,
  62         pca9532,
  63         pca9533,
  64 };
  65
  66 static const struct i2c_device_id pca9532_id[] = {
  67         { "pca9530", pca9530 },
  68         { "pca9531", pca9531 },
  69         { "pca9532", pca9532 },
  70         { "pca9533", pca9533 },
  71         { }
  72 };
  73
  74 MODULE_DEVICE_TABLE(i2c, pca9532_id);
  75
  76 static const struct pca9532_chip_info pca9532_chip_info_tbl[] = {
  77         [pca9530] = {
  78                 .num_leds = 2,
  79         },
  80         [pca9531] = {
  81                 .num_leds = 8,
  82         },
  83         [pca9532] = {
  84                 .num_leds = 16,
  85         },
  86         [pca9533] = {
  87                 .num_leds = 4,
  88         },
  89 };
  90
  91 #ifdef CONFIG_OF
  92 static const struct of_device_id of_pca9532_leds_match[] = {
  93         { .compatible = "nxp,pca9530", .data = (void *)pca9530 },
  94         { .compatible = "nxp,pca9531", .data = (void *)pca9531 },
  95         { .compatible = "nxp,pca9532", .data = (void *)pca9532 },
  96         { .compatible = "nxp,pca9533", .data = (void *)pca9533 },
  97         {},
  98 };
  99
 100 MODULE_DEVICE_TABLE(of, of_pca9532_leds_match);
 101 #endif
 102
 103 static struct i2c_driver pca9532_driver = {
 104         .driver = {
 105                 .name = "leds-pca953x",
 106                 .of_match_table = of_match_ptr(of_pca9532_leds_match),
 107         },
 108         .probe = pca9532_probe,
 109         .remove = pca9532_remove,
 110         .id_table = pca9532_id,
 111 };
 112
 113 /* We have two pwm/blinkers, but 16 possible leds to drive. Additionally,
 114  * the clever Thecus people are using one pwm to drive the beeper. So,
 115  * as a compromise we average one pwm to the values requested by all
 116  * leds that are not ON/OFF.
 117  * */
 118 static int pca9532_calcpwm(struct i2c_client *client, int pwm, int blink,
 119         enum led_brightness value)
 120 {
 121         int a = 0, b = 0, i = 0;
 122         struct pca9532_data *data = i2c_get_clientdata(client);
 123         for (i = 0; i < data->chip_info->num_leds; i++) {
 124                 if (data->leds[i].type == PCA9532_TYPE_LED &&
 125                         data->leds[i].state == PCA9532_PWM0+pwm) {
 126                                 a++;
 127                                 b += data->leds[i].ldev.brightness;
 128                 }
 129         }
 130         if (a == 0) {
 131                 dev_err(&client->dev,
 132                 "fear of division by zero %d/%d, wanted %d\n",
 133                         b, a, value);
 134                 return -EINVAL;
 135         }
 136         b = b/a;
 137         if (b > 0xFF)
 138                 return -EINVAL;
 139         data->pwm[pwm] = b;
 140         data->psc[pwm] = blink;
 141         return 0;
 142 }
 143
 144 static int pca9532_setpwm(struct i2c_client *client, int pwm)
 145 {
 146         struct pca9532_data *data = i2c_get_clientdata(client);
 147         u8 maxleds = data->chip_info->num_leds;
 148
 149         mutex_lock(&data->update_lock);
 150         i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, pwm),
 151                 data->pwm[pwm]);
 152         i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, pwm),
 153                 data->psc[pwm]);
 154         mutex_unlock(&data->update_lock);
 155         return 0;
 156 }
 157
 158 /* Set LED routing */
 159 static void pca9532_setled(struct pca9532_led *led)
 160 {
 161         struct i2c_client *client = led->client;
 162         struct pca9532_data *data = i2c_get_clientdata(client);
 163         u8 maxleds = data->chip_info->num_leds;
 164         char reg;
 165
 166         mutex_lock(&data->update_lock);
 167         reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
 168         /* zero led bits */
 169         reg = reg & ~(0x3<<LED_NUM(led->id)*2);
 170         /* set the new value */
 171         reg = reg | (led->state << LED_NUM(led->id)*2);
 172         i2c_smbus_write_byte_data(client, LED_REG(maxleds, led->id), reg);
 173         mutex_unlock(&data->update_lock);
 174 }
 175
 176 static int pca9532_set_brightness(struct led_classdev *led_cdev,
 177         enum led_brightness value)
 178 {
 179         int err = 0;
 180         struct pca9532_led *led = ldev_to_led(led_cdev);
 181
 182         if (value == LED_OFF)
 183                 led->state = PCA9532_OFF;
 184         else if (value == LED_FULL)
 185                 led->state = PCA9532_ON;
 186         else {
 187                 led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */
 188                 err = pca9532_calcpwm(led->client, 0, 0, value);
 189                 if (err)
 190                         return err;
 191         }
 192         if (led->state == PCA9532_PWM0)
 193                 pca9532_setpwm(led->client, 0);
 194         pca9532_setled(led);
 195         return err;
 196 }
 197
 198 static int pca9532_set_blink(struct led_classdev *led_cdev,
 199         unsigned long *delay_on, unsigned long *delay_off)
 200 {
 201         struct pca9532_led *led = ldev_to_led(led_cdev);
 202         struct i2c_client *client = led->client;
 203         int psc;
 204         int err = 0;
 205
 206         if (*delay_on == 0 && *delay_off == 0) {
 207                 /* led subsystem ask us for a blink rate */
 208                 *delay_on = 1000;
 209                 *delay_off = 1000;
 210         }
 211         if (*delay_on != *delay_off || *delay_on > 1690 || *delay_on < 6)
 212                 return -EINVAL;
 213
 214         /* Thecus specific: only use PSC/PWM 0 */
 215         psc = (*delay_on * 152-1)/1000;
 216         err = pca9532_calcpwm(client, 0, psc, led_cdev->brightness);
 217         if (err)
 218                 return err;
 219         if (led->state == PCA9532_PWM0)
 220                 pca9532_setpwm(led->client, 0);
 221         pca9532_setled(led);
 222
 223         return 0;
 224 }
 225
 226 static int pca9532_event(struct input_dev *dev, unsigned int type,
 227         unsigned int code, int value)
 228 {
 229         struct pca9532_data *data = input_get_drvdata(dev);
 230
 231         if (!(type == EV_SND && (code == SND_BELL || code == SND_TONE)))
 232                 return -1;
 233
 234         /* XXX: allow different kind of beeps with psc/pwm modifications */
 235         if (value > 1 && value < 32767)
 236                 data->pwm[1] = 127;
 237         else
 238                 data->pwm[1] = 0;
 239
 240         schedule_work(&data->work);
 241
 242         return 0;
 243 }
 244
 245 static void pca9532_input_work(struct work_struct *work)
 246 {
 247         struct pca9532_data *data =
 248                 container_of(work, struct pca9532_data, work);
 249         u8 maxleds = data->chip_info->num_leds;
 250
 251         mutex_lock(&data->update_lock);
 252         i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(maxleds, 1),
 253                 data->pwm[1]);
 254         mutex_unlock(&data->update_lock);
 255 }
 256
 257 static enum pca9532_state pca9532_getled(struct pca9532_led *led)
 258 {
 259         struct i2c_client *client = led->client;
 260         struct pca9532_data *data = i2c_get_clientdata(client);
 261         u8 maxleds = data->chip_info->num_leds;
 262         char reg;
 263         enum pca9532_state ret;
 264
 265         mutex_lock(&data->update_lock);
 266         reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
 267         ret = reg >> LED_NUM(led->id)/2;
 268         mutex_unlock(&data->update_lock);
 269         return ret;
 270 }
 271
 272 #ifdef CONFIG_LEDS_PCA9532_GPIO
 273 static int pca9532_gpio_request_pin(struct gpio_chip *gc, unsigned offset)
 274 {
 275         struct pca9532_data *data = gpiochip_get_data(gc);
 276         struct pca9532_led *led = &data->leds[offset];
 277
 278         if (led->type == PCA9532_TYPE_GPIO)
 279                 return 0;
 280
 281         return -EBUSY;
 282 }
 283
 284 static void pca9532_gpio_set_value(struct gpio_chip *gc, unsigned offset, int val)
 285 {
 286         struct pca9532_data *data = gpiochip_get_data(gc);
 287         struct pca9532_led *led = &data->leds[offset];
 288
 289         if (val)
 290                 led->state = PCA9532_ON;
 291         else
 292                 led->state = PCA9532_OFF;
 293
 294         pca9532_setled(led);
 295 }
 296
 297 static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
 298 {
 299         struct pca9532_data *data = gpiochip_get_data(gc);
 300         unsigned char reg;
 301
 302         reg = i2c_smbus_read_byte_data(data->client, PCA9532_REG_INPUT(offset));
 303
 304         return !!(reg & (1 << (offset % 8)));
 305 }
 306
 307 static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
 308 {
 309         /* To use as input ensure pin is not driven */
 310         pca9532_gpio_set_value(gc, offset, 0);
 311
 312         return 0;
 313 }
 314
 315 static int pca9532_gpio_direction_output(struct gpio_chip *gc, unsigned offset, int val)
 316 {
 317         pca9532_gpio_set_value(gc, offset, val);
 318
 319         return 0;
 320 }
 321 #endif /* CONFIG_LEDS_PCA9532_GPIO */
 322
 323 static int pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
 324 {
 325         int i = n_devs;
 326
 327         if (!data)
 328                 return -EINVAL;
 329
 330         while (--i >= 0) {
 331                 switch (data->leds[i].type) {
 332                 case PCA9532_TYPE_NONE:
 333                 case PCA9532_TYPE_GPIO:
 334                         break;
 335                 case PCA9532_TYPE_LED:
 336                         led_classdev_unregister(&data->leds[i].ldev);
 337                         break;
 338                 case PCA9532_TYPE_N2100_BEEP:
 339                         if (data->idev != NULL) {
 340                                 cancel_work_sync(&data->work);
 341                                 data->idev = NULL;
 342                         }
 343                         break;
 344                 }
 345         }
 346
 347 #ifdef CONFIG_LEDS_PCA9532_GPIO
 348         if (data->gpio.parent)
 349                 gpiochip_remove(&data->gpio);
 350 #endif
 351
 352         return 0;
 353 }
 354
 355 static int pca9532_configure(struct i2c_client *client,
 356         struct pca9532_data *data, struct pca9532_platform_data *pdata)
 357 {
 358         int i, err = 0;
 359         int gpios = 0;
 360         u8 maxleds = data->chip_info->num_leds;
 361
 362         for (i = 0; i < 2; i++) {
 363                 data->pwm[i] = pdata->pwm[i];
 364                 data->psc[i] = pdata->psc[i];
 365                 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, i),
 366                         data->pwm[i]);
 367                 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, i),
 368                         data->psc[i]);
 369         }
 370
 371         for (i = 0; i < data->chip_info->num_leds; i++) {
 372                 struct pca9532_led *led = &data->leds[i];
 373                 struct pca9532_led *pled = &pdata->leds[i];
 374                 led->client = client;
 375                 led->id = i;
 376                 led->type = pled->type;
 377                 switch (led->type) {
 378                 case PCA9532_TYPE_NONE:
 379                         break;
 380                 case PCA9532_TYPE_GPIO:
 381                         gpios++;
 382                         break;
 383                 case PCA9532_TYPE_LED:
 384                         if (pled->state == PCA9532_KEEP)
 385                                 led->state = pca9532_getled(led);
 386                         else
 387                                 led->state = pled->state;
 388                         led->name = pled->name;
 389                         led->ldev.name = led->name;
 390                         led->ldev.default_trigger = pled->default_trigger;
 391                         led->ldev.brightness = LED_OFF;
 392                         led->ldev.brightness_set_blocking =
 393                                                 pca9532_set_brightness;
 394                         led->ldev.blink_set = pca9532_set_blink;
 395                         err = led_classdev_register(&client->dev, &led->ldev);
 396                         if (err < 0) {
 397                                 dev_err(&client->dev,
 398                                         "couldn't register LED %s\n",
 399                                         led->name);
 400                                 goto exit;
 401                         }
 402                         pca9532_setled(led);
 403                         break;
 404                 case PCA9532_TYPE_N2100_BEEP:
 405                         BUG_ON(data->idev);
 406                         led->state = PCA9532_PWM1;
 407                         pca9532_setled(led);
 408                         data->idev = devm_input_allocate_device(&client->dev);
 409                         if (data->idev == NULL) {
 410                                 err = -ENOMEM;
 411                                 goto exit;
 412                         }
 413                         data->idev->name = pled->name;
 414                         data->idev->phys = "i2c/pca9532";
 415                         data->idev->id.bustype = BUS_HOST;
 416                         data->idev->id.vendor = 0x001f;
 417                         data->idev->id.product = 0x0001;
 418                         data->idev->id.version = 0x0100;
 419                         data->idev->evbit[0] = BIT_MASK(EV_SND);
 420                         data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
 421                                                 BIT_MASK(SND_TONE);
 422                         data->idev->event = pca9532_event;
 423                         input_set_drvdata(data->idev, data);
 424                         INIT_WORK(&data->work, pca9532_input_work);
 425                         err = input_register_device(data->idev);
 426                         if (err) {
 427                                 cancel_work_sync(&data->work);
 428                                 data->idev = NULL;
 429                                 goto exit;
 430                         }
 431                         break;
 432                 }
 433         }
 434
 435 #ifdef CONFIG_LEDS_PCA9532_GPIO
 436         if (gpios) {
 437                 data->gpio.label = "gpio-pca9532";
 438                 data->gpio.direction_input = pca9532_gpio_direction_input;
 439                 data->gpio.direction_output = pca9532_gpio_direction_output;
 440                 data->gpio.set = pca9532_gpio_set_value;
 441                 data->gpio.get = pca9532_gpio_get_value;
 442                 data->gpio.request = pca9532_gpio_request_pin;
 443                 data->gpio.can_sleep = 1;
 444                 data->gpio.base = pdata->gpio_base;
 445                 data->gpio.ngpio = data->chip_info->num_leds;
 446                 data->gpio.parent = &client->dev;
 447                 data->gpio.owner = THIS_MODULE;
 448
 449                 err = gpiochip_add_data(&data->gpio, data);
 450                 if (err) {
 451                         /* Use data->gpio.dev as a flag for freeing gpiochip */
 452                         data->gpio.parent = NULL;
 453                         dev_warn(&client->dev, "could not add gpiochip\n");
 454                 } else {
 455                         dev_info(&client->dev, "gpios %i...%i\n",
 456                                 data->gpio.base, data->gpio.base +
 457                                 data->gpio.ngpio - 1);
 458                 }
 459         }
 460 #endif
 461
 462         return 0;
 463
 464 exit:
 465         pca9532_destroy_devices(data, i);
 466         return err;
 467 }
 468
 469 static struct pca9532_platform_data *
 470 pca9532_of_populate_pdata(struct device *dev, struct device_node *np)
 471 {
 472         struct pca9532_platform_data *pdata;
 473         struct device_node *child;
 474         const struct of_device_id *match;
 475         int devid, maxleds;
 476         int i = 0;
 477         const char *state;
 478
 479         match = of_match_device(of_pca9532_leds_match, dev);
 480         if (!match)
 481                 return ERR_PTR(-ENODEV);
 482
 483         devid = (int)(uintptr_t)match->data;
 484         maxleds = pca9532_chip_info_tbl[devid].num_leds;
 485
 486         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 487         if (!pdata)
 488                 return ERR_PTR(-ENOMEM);
 489
 490         for_each_child_of_node(np, child) {
 491                 if (of_property_read_string(child, "label",
 492                                             &pdata->leds[i].name))
 493                         pdata->leds[i].name = child->name;
 494                 of_property_read_u32(child, "type", &pdata->leds[i].type);
 495                 of_property_read_string(child, "linux,default-trigger",
 496                                         &pdata->leds[i].default_trigger);
 497                 if (!of_property_read_string(child, "default-state", &state)) {
 498                         if (!strcmp(state, "on"))
 499                                 pdata->leds[i].state = PCA9532_ON;
 500                         else if (!strcmp(state, "keep"))
 501                                 pdata->leds[i].state = PCA9532_KEEP;
 502                 }
 503                 if (++i >= maxleds) {
 504                         of_node_put(child);
 505                         break;
 506                 }
 507         }
 508
 509         return pdata;
 510 }
 511
 512 static int pca9532_probe(struct i2c_client *client,
 513         const struct i2c_device_id *id)
 514 {
 515         int devid;
 516         struct pca9532_data *data = i2c_get_clientdata(client);
 517         struct pca9532_platform_data *pca9532_pdata =
 518                         dev_get_platdata(&client->dev);
 519         struct device_node *np = client->dev.of_node;
 520
 521         if (!pca9532_pdata) {
 522                 if (np) {
 523                         pca9532_pdata =
 524                                 pca9532_of_populate_pdata(&client->dev, np);
 525                         if (IS_ERR(pca9532_pdata))
 526                                 return PTR_ERR(pca9532_pdata);
 527                 } else {
 528                         dev_err(&client->dev, "no platform data\n");
 529                         return -EINVAL;
 530                 }
 531                 devid = (int)(uintptr_t)of_match_device(
 532                         of_pca9532_leds_match, &client->dev)->data;
 533         } else {
 534                 devid = id->driver_data;
 535         }
 536
 537         if (!i2c_check_functionality(client->adapter,
 538                 I2C_FUNC_SMBUS_BYTE_DATA))
 539                 return -EIO;
 540
 541         data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
 542         if (!data)
 543                 return -ENOMEM;
 544
 545         data->chip_info = &pca9532_chip_info_tbl[devid];
 546
 547         dev_info(&client->dev, "setting platform data\n");
 548         i2c_set_clientdata(client, data);
 549         data->client = client;
 550         mutex_init(&data->update_lock);
 551
 552         return pca9532_configure(client, data, pca9532_pdata);
 553 }
 554
 555 static int pca9532_remove(struct i2c_client *client)
 556 {
 557         struct pca9532_data *data = i2c_get_clientdata(client);
 558         int err;
 559
 560         err = pca9532_destroy_devices(data, data->chip_info->num_leds);
 561         if (err)
 562                 return err;
 563
 564         return 0;
 565 }
 566
 567 module_i2c_driver(pca9532_driver);
 568
 569 MODULE_AUTHOR("Riku Voipio");
 570 MODULE_LICENSE("GPL");
 571 MODULE_DESCRIPTION("PCA 9532 LED dimmer");