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 #ifdef CONFIG_LEDS_PCA9532_GPIO
 258 static int pca9532_gpio_request_pin(struct gpio_chip *gc, unsigned offset)
 259 {
 260         struct pca9532_data *data = gpiochip_get_data(gc);
 261         struct pca9532_led *led = &data->leds[offset];
 262
 263         if (led->type == PCA9532_TYPE_GPIO)
 264                 return 0;
 265
 266         return -EBUSY;
 267 }
 268
 269 static void pca9532_gpio_set_value(struct gpio_chip *gc, unsigned offset, int val)
 270 {
 271         struct pca9532_data *data = gpiochip_get_data(gc);
 272         struct pca9532_led *led = &data->leds[offset];
 273
 274         if (val)
 275                 led->state = PCA9532_ON;
 276         else
 277                 led->state = PCA9532_OFF;
 278
 279         pca9532_setled(led);
 280 }
 281
 282 static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
 283 {
 284         struct pca9532_data *data = gpiochip_get_data(gc);
 285         unsigned char reg;
 286
 287         reg = i2c_smbus_read_byte_data(data->client, PCA9532_REG_INPUT(offset));
 288
 289         return !!(reg & (1 << (offset % 8)));
 290 }
 291
 292 static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
 293 {
 294         /* To use as input ensure pin is not driven */
 295         pca9532_gpio_set_value(gc, offset, 0);
 296
 297         return 0;
 298 }
 299
 300 static int pca9532_gpio_direction_output(struct gpio_chip *gc, unsigned offset, int val)
 301 {
 302         pca9532_gpio_set_value(gc, offset, val);
 303
 304         return 0;
 305 }
 306 #endif /* CONFIG_LEDS_PCA9532_GPIO */
 307
 308 static int pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
 309 {
 310         int i = n_devs;
 311
 312         if (!data)
 313                 return -EINVAL;
 314
 315         while (--i >= 0) {
 316                 switch (data->leds[i].type) {
 317                 case PCA9532_TYPE_NONE:
 318                 case PCA9532_TYPE_GPIO:
 319                         break;
 320                 case PCA9532_TYPE_LED:
 321                         led_classdev_unregister(&data->leds[i].ldev);
 322                         break;
 323                 case PCA9532_TYPE_N2100_BEEP:
 324                         if (data->idev != NULL) {
 325                                 cancel_work_sync(&data->work);
 326                                 data->idev = NULL;
 327                         }
 328                         break;
 329                 }
 330         }
 331
 332 #ifdef CONFIG_LEDS_PCA9532_GPIO
 333         if (data->gpio.parent)
 334                 gpiochip_remove(&data->gpio);
 335 #endif
 336
 337         return 0;
 338 }
 339
 340 static int pca9532_configure(struct i2c_client *client,
 341         struct pca9532_data *data, struct pca9532_platform_data *pdata)
 342 {
 343         int i, err = 0;
 344         int gpios = 0;
 345         u8 maxleds = data->chip_info->num_leds;
 346
 347         for (i = 0; i < 2; i++) {
 348                 data->pwm[i] = pdata->pwm[i];
 349                 data->psc[i] = pdata->psc[i];
 350                 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, i),
 351                         data->pwm[i]);
 352                 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, i),
 353                         data->psc[i]);
 354         }
 355
 356         for (i = 0; i < data->chip_info->num_leds; i++) {
 357                 struct pca9532_led *led = &data->leds[i];
 358                 struct pca9532_led *pled = &pdata->leds[i];
 359                 led->client = client;
 360                 led->id = i;
 361                 led->type = pled->type;
 362                 switch (led->type) {
 363                 case PCA9532_TYPE_NONE:
 364                         break;
 365                 case PCA9532_TYPE_GPIO:
 366                         gpios++;
 367                         break;
 368                 case PCA9532_TYPE_LED:
 369                         led->state = pled->state;
 370                         led->name = pled->name;
 371                         led->ldev.name = led->name;
 372                         led->ldev.default_trigger = led->default_trigger;
 373                         led->ldev.brightness = LED_OFF;
 374                         led->ldev.brightness_set_blocking =
 375                                                 pca9532_set_brightness;
 376                         led->ldev.blink_set = pca9532_set_blink;
 377                         err = led_classdev_register(&client->dev, &led->ldev);
 378                         if (err < 0) {
 379                                 dev_err(&client->dev,
 380                                         "couldn't register LED %s\n",
 381                                         led->name);
 382                                 goto exit;
 383                         }
 384                         pca9532_setled(led);
 385                         break;
 386                 case PCA9532_TYPE_N2100_BEEP:
 387                         BUG_ON(data->idev);
 388                         led->state = PCA9532_PWM1;
 389                         pca9532_setled(led);
 390                         data->idev = devm_input_allocate_device(&client->dev);
 391                         if (data->idev == NULL) {
 392                                 err = -ENOMEM;
 393                                 goto exit;
 394                         }
 395                         data->idev->name = pled->name;
 396                         data->idev->phys = "i2c/pca9532";
 397                         data->idev->id.bustype = BUS_HOST;
 398                         data->idev->id.vendor = 0x001f;
 399                         data->idev->id.product = 0x0001;
 400                         data->idev->id.version = 0x0100;
 401                         data->idev->evbit[0] = BIT_MASK(EV_SND);
 402                         data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
 403                                                 BIT_MASK(SND_TONE);
 404                         data->idev->event = pca9532_event;
 405                         input_set_drvdata(data->idev, data);
 406                         INIT_WORK(&data->work, pca9532_input_work);
 407                         err = input_register_device(data->idev);
 408                         if (err) {
 409                                 cancel_work_sync(&data->work);
 410                                 data->idev = NULL;
 411                                 goto exit;
 412                         }
 413                         break;
 414                 }
 415         }
 416
 417 #ifdef CONFIG_LEDS_PCA9532_GPIO
 418         if (gpios) {
 419                 data->gpio.label = "gpio-pca9532";
 420                 data->gpio.direction_input = pca9532_gpio_direction_input;
 421                 data->gpio.direction_output = pca9532_gpio_direction_output;
 422                 data->gpio.set = pca9532_gpio_set_value;
 423                 data->gpio.get = pca9532_gpio_get_value;
 424                 data->gpio.request = pca9532_gpio_request_pin;
 425                 data->gpio.can_sleep = 1;
 426                 data->gpio.base = pdata->gpio_base;
 427                 data->gpio.ngpio = data->chip_info->num_leds;
 428                 data->gpio.parent = &client->dev;
 429                 data->gpio.owner = THIS_MODULE;
 430
 431                 err = gpiochip_add_data(&data->gpio, data);
 432                 if (err) {
 433                         /* Use data->gpio.dev as a flag for freeing gpiochip */
 434                         data->gpio.parent = NULL;
 435                         dev_warn(&client->dev, "could not add gpiochip\n");
 436                 } else {
 437                         dev_info(&client->dev, "gpios %i...%i\n",
 438                                 data->gpio.base, data->gpio.base +
 439                                 data->gpio.ngpio - 1);
 440                 }
 441         }
 442 #endif
 443
 444         return 0;
 445
 446 exit:
 447         pca9532_destroy_devices(data, i);
 448         return err;
 449 }
 450
 451 static struct pca9532_platform_data *
 452 pca9532_of_populate_pdata(struct device *dev, struct device_node *np)
 453 {
 454         struct pca9532_platform_data *pdata;
 455         struct device_node *child;
 456         const struct of_device_id *match;
 457         int devid, maxleds;
 458         int i = 0;
 459
 460         match = of_match_device(of_pca9532_leds_match, dev);
 461         if (!match)
 462                 return ERR_PTR(-ENODEV);
 463
 464         devid = (int)(uintptr_t)match->data;
 465         maxleds = pca9532_chip_info_tbl[devid].num_leds;
 466
 467         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 468         if (!pdata)
 469                 return ERR_PTR(-ENOMEM);
 470
 471         for_each_child_of_node(np, child) {
 472                 if (of_property_read_string(child, "label",
 473                                             &pdata->leds[i].name))
 474                         pdata->leds[i].name = child->name;
 475                 of_property_read_u32(child, "type", &pdata->leds[i].type);
 476                 of_property_read_string(child, "linux,default-trigger",
 477                                         &pdata->leds[i].default_trigger);
 478                 if (++i >= maxleds) {
 479                         of_node_put(child);
 480                         break;
 481                 }
 482         }
 483
 484         return pdata;
 485 }
 486
 487 static int pca9532_probe(struct i2c_client *client,
 488         const struct i2c_device_id *id)
 489 {
 490         int devid;
 491         struct pca9532_data *data = i2c_get_clientdata(client);
 492         struct pca9532_platform_data *pca9532_pdata =
 493                         dev_get_platdata(&client->dev);
 494         struct device_node *np = client->dev.of_node;
 495
 496         if (!pca9532_pdata) {
 497                 if (np) {
 498                         pca9532_pdata =
 499                                 pca9532_of_populate_pdata(&client->dev, np);
 500                         if (IS_ERR(pca9532_pdata))
 501                                 return PTR_ERR(pca9532_pdata);
 502                 } else {
 503                         dev_err(&client->dev, "no platform data\n");
 504                         return -EINVAL;
 505                 }
 506                 devid = (int)(uintptr_t)of_match_device(
 507                         of_pca9532_leds_match, &client->dev)->data;
 508         } else {
 509                 devid = id->driver_data;
 510         }
 511
 512         if (!i2c_check_functionality(client->adapter,
 513                 I2C_FUNC_SMBUS_BYTE_DATA))
 514                 return -EIO;
 515
 516         data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
 517         if (!data)
 518                 return -ENOMEM;
 519
 520         data->chip_info = &pca9532_chip_info_tbl[devid];
 521
 522         dev_info(&client->dev, "setting platform data\n");
 523         i2c_set_clientdata(client, data);
 524         data->client = client;
 525         mutex_init(&data->update_lock);
 526
 527         return pca9532_configure(client, data, pca9532_pdata);
 528 }
 529
 530 static int pca9532_remove(struct i2c_client *client)
 531 {
 532         struct pca9532_data *data = i2c_get_clientdata(client);
 533         int err;
 534
 535         err = pca9532_destroy_devices(data, data->chip_info->num_leds);
 536         if (err)
 537                 return err;
 538
 539         return 0;
 540 }
 541
 542 module_i2c_driver(pca9532_driver);
 543
 544 MODULE_AUTHOR("Riku Voipio");
 545 MODULE_LICENSE("GPL");
 546 MODULE_DESCRIPTION("PCA 9532 LED dimmer");