drivers/leds/leds-pca9532.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * pca9532.c - 16-bit Led dimmer
   4  *
   5  * Copyright (C) 2011 Jan Weitzel
   6  * Copyright (C) 2008 Riku Voipio
   7  *
   8  * Datasheet: http://www.nxp.com/documents/data_sheet/PCA9532.pdf
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/i2c.h>
  13 #include <linux/slab.h>
  14 #include <linux/leds.h>
  15 #include <linux/input.h>
  16 #include <linux/mutex.h>
  17 #include <linux/workqueue.h>
  18 #include <linux/leds-pca9532.h>
  19 #include <linux/gpio/driver.h>
  20 #include <linux/of.h>
  21
  22 /* m =  num_leds*/
  23 #define PCA9532_REG_INPUT(i)    ((i) >> 3)
  24 #define PCA9532_REG_OFFSET(m)   ((m) >> 4)
  25 #define PCA9532_REG_PSC(m, i)   (PCA9532_REG_OFFSET(m) + 0x1 + (i) * 2)
  26 #define PCA9532_REG_PWM(m, i)   (PCA9532_REG_OFFSET(m) + 0x2 + (i) * 2)
  27 #define LED_REG(m, led)         (PCA9532_REG_OFFSET(m) + 0x5 + (led >> 2))
  28 #define LED_NUM(led)            (led & 0x3)
  29 #define LED_SHIFT(led)          (LED_NUM(led) * 2)
  30 #define LED_MASK(led)           (0x3 << LED_SHIFT(led))
  31
  32 #define PCA9532_PWM_PERIOD_DIV  152
  33 #define PCA9532_PWM_DUTY_DIV    256
  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
  52 #define PCA9532_PWM_ID_0        0
  53 #define PCA9532_PWM_ID_1        1
  54         u8 pwm[2];
  55         u8 psc[2];
  56         bool hw_blink;
  57 };
  58
  59 static int pca9532_probe(struct i2c_client *client);
  60 static void pca9532_remove(struct i2c_client *client);
  61
  62 enum {
  63         pca9530,
  64         pca9531,
  65         pca9532,
  66         pca9533,
  67 };
  68
  69 static const struct i2c_device_id pca9532_id[] = {
  70         { "pca9530", pca9530 },
  71         { "pca9531", pca9531 },
  72         { "pca9532", pca9532 },
  73         { "pca9533", pca9533 },
  74         { }
  75 };
  76
  77 MODULE_DEVICE_TABLE(i2c, pca9532_id);
  78
  79 static const struct pca9532_chip_info pca9532_chip_info_tbl[] = {
  80         [pca9530] = {
  81                 .num_leds = 2,
  82         },
  83         [pca9531] = {
  84                 .num_leds = 8,
  85         },
  86         [pca9532] = {
  87                 .num_leds = 16,
  88         },
  89         [pca9533] = {
  90                 .num_leds = 4,
  91         },
  92 };
  93
  94 #ifdef CONFIG_OF
  95 static const struct of_device_id of_pca9532_leds_match[] = {
  96         { .compatible = "nxp,pca9530", .data = (void *)pca9530 },
  97         { .compatible = "nxp,pca9531", .data = (void *)pca9531 },
  98         { .compatible = "nxp,pca9532", .data = (void *)pca9532 },
  99         { .compatible = "nxp,pca9533", .data = (void *)pca9533 },
 100         {},
 101 };
 102
 103 MODULE_DEVICE_TABLE(of, of_pca9532_leds_match);
 104 #endif
 105
 106 static struct i2c_driver pca9532_driver = {
 107         .driver = {
 108                 .name = "leds-pca953x",
 109                 .of_match_table = of_match_ptr(of_pca9532_leds_match),
 110         },
 111         .probe = pca9532_probe,
 112         .remove = pca9532_remove,
 113         .id_table = pca9532_id,
 114 };
 115
 116 /* We have two pwm/blinkers, but 16 possible leds to drive. Additionally,
 117  * the clever Thecus people are using one pwm to drive the beeper. So,
 118  * as a compromise we average one pwm to the values requested by all
 119  * leds that are not ON/OFF.
 120  * */
 121 static int pca9532_calcpwm(struct i2c_client *client, int pwm, int blink,
 122         enum led_brightness value)
 123 {
 124         int a = 0, b = 0, i = 0;
 125         struct pca9532_data *data = i2c_get_clientdata(client);
 126         for (i = 0; i < data->chip_info->num_leds; i++) {
 127                 if (data->leds[i].type == PCA9532_TYPE_LED &&
 128                         data->leds[i].state == PCA9532_PWM0+pwm) {
 129                                 a++;
 130                                 b += data->leds[i].ldev.brightness;
 131                 }
 132         }
 133         if (a == 0) {
 134                 dev_err(&client->dev,
 135                 "fear of division by zero %d/%d, wanted %d\n",
 136                         b, a, value);
 137                 return -EINVAL;
 138         }
 139         b = b/a;
 140         if (b > 0xFF)
 141                 return -EINVAL;
 142         data->pwm[pwm] = b;
 143         data->psc[pwm] = blink;
 144         return 0;
 145 }
 146
 147 static int pca9532_setpwm(struct i2c_client *client, int pwm)
 148 {
 149         struct pca9532_data *data = i2c_get_clientdata(client);
 150         u8 maxleds = data->chip_info->num_leds;
 151
 152         mutex_lock(&data->update_lock);
 153         i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, pwm),
 154                 data->pwm[pwm]);
 155         i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, pwm),
 156                 data->psc[pwm]);
 157         mutex_unlock(&data->update_lock);
 158         return 0;
 159 }
 160
 161 /* Set LED routing */
 162 static void pca9532_setled(struct pca9532_led *led)
 163 {
 164         struct i2c_client *client = led->client;
 165         struct pca9532_data *data = i2c_get_clientdata(client);
 166         u8 maxleds = data->chip_info->num_leds;
 167         char reg;
 168
 169         mutex_lock(&data->update_lock);
 170         reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
 171         /* zero led bits */
 172         reg = reg & ~LED_MASK(led->id);
 173         /* set the new value */
 174         reg = reg | (led->state << LED_SHIFT(led->id));
 175         i2c_smbus_write_byte_data(client, LED_REG(maxleds, led->id), reg);
 176         mutex_unlock(&data->update_lock);
 177 }
 178
 179 static int pca9532_set_brightness(struct led_classdev *led_cdev,
 180         enum led_brightness value)
 181 {
 182         int err = 0;
 183         struct pca9532_led *led = ldev_to_led(led_cdev);
 184
 185         if (value == LED_OFF)
 186                 led->state = PCA9532_OFF;
 187         else if (value == LED_FULL)
 188                 led->state = PCA9532_ON;
 189         else {
 190                 led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */
 191                 err = pca9532_calcpwm(led->client, PCA9532_PWM_ID_0, 0, value);
 192                 if (err)
 193                         return err;
 194         }
 195         if (led->state == PCA9532_PWM0)
 196                 pca9532_setpwm(led->client, PCA9532_PWM_ID_0);
 197         pca9532_setled(led);
 198         return err;
 199 }
 200
 201 static int pca9532_update_hw_blink(struct pca9532_led *led,
 202                                    unsigned long delay_on, unsigned long delay_off)
 203 {
 204         struct pca9532_data *data = i2c_get_clientdata(led->client);
 205         unsigned int psc;
 206         int i;
 207
 208         /* Look for others LEDs that already use PWM1 */
 209         for (i = 0; i < data->chip_info->num_leds; i++) {
 210                 struct pca9532_led *other = &data->leds[i];
 211
 212                 if (other == led)
 213                         continue;
 214
 215                 if (other->state == PCA9532_PWM1) {
 216                         if (other->ldev.blink_delay_on != delay_on ||
 217                             other->ldev.blink_delay_off != delay_off) {
 218                                 /* HW can handle only one blink configuration at a time */
 219                                 return -EINVAL;
 220                         }
 221                 }
 222         }
 223
 224         psc = ((delay_on + delay_off) * PCA9532_PWM_PERIOD_DIV - 1) / 1000;
 225         if (psc > U8_MAX) {
 226                 /* Blink period too long to be handled by hardware */
 227                 return -EINVAL;
 228         }
 229
 230         led->state = PCA9532_PWM1;
 231         data->psc[PCA9532_PWM_ID_1] = psc;
 232         data->pwm[PCA9532_PWM_ID_1] = (delay_on * PCA9532_PWM_DUTY_DIV) / (delay_on + delay_off);
 233
 234         return pca9532_setpwm(data->client, PCA9532_PWM_ID_1);
 235 }
 236
 237 static int pca9532_set_blink(struct led_classdev *led_cdev,
 238         unsigned long *delay_on, unsigned long *delay_off)
 239 {
 240         struct pca9532_led *led = ldev_to_led(led_cdev);
 241         struct i2c_client *client = led->client;
 242         struct pca9532_data *data = i2c_get_clientdata(client);
 243         int err;
 244
 245         if (!data->hw_blink)
 246                 return -EINVAL;
 247
 248         if (*delay_on == 0 && *delay_off == 0) {
 249                 /* led subsystem ask us for a blink rate */
 250                 *delay_on = 500;
 251                 *delay_off = 500;
 252         }
 253
 254         err = pca9532_update_hw_blink(led, *delay_on, *delay_off);
 255         if (err)
 256                 return err;
 257
 258         pca9532_setled(led);
 259
 260         return 0;
 261 }
 262
 263 static int pca9532_event(struct input_dev *dev, unsigned int type,
 264         unsigned int code, int value)
 265 {
 266         struct pca9532_data *data = input_get_drvdata(dev);
 267
 268         if (!(type == EV_SND && (code == SND_BELL || code == SND_TONE)))
 269                 return -1;
 270
 271         /* XXX: allow different kind of beeps with psc/pwm modifications */
 272         if (value > 1 && value < 32767)
 273                 data->pwm[PCA9532_PWM_ID_1] = 127;
 274         else
 275                 data->pwm[PCA9532_PWM_ID_1] = 0;
 276
 277         schedule_work(&data->work);
 278
 279         return 0;
 280 }
 281
 282 static void pca9532_input_work(struct work_struct *work)
 283 {
 284         struct pca9532_data *data =
 285                 container_of(work, struct pca9532_data, work);
 286         u8 maxleds = data->chip_info->num_leds;
 287
 288         mutex_lock(&data->update_lock);
 289         i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(maxleds, 1),
 290                 data->pwm[PCA9532_PWM_ID_1]);
 291         mutex_unlock(&data->update_lock);
 292 }
 293
 294 static enum pca9532_state pca9532_getled(struct pca9532_led *led)
 295 {
 296         struct i2c_client *client = led->client;
 297         struct pca9532_data *data = i2c_get_clientdata(client);
 298         u8 maxleds = data->chip_info->num_leds;
 299         char reg;
 300         enum pca9532_state ret;
 301
 302         mutex_lock(&data->update_lock);
 303         reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
 304         ret = (reg & LED_MASK(led->id)) >> LED_SHIFT(led->id);
 305         mutex_unlock(&data->update_lock);
 306         return ret;
 307 }
 308
 309 #ifdef CONFIG_LEDS_PCA9532_GPIO
 310 static int pca9532_gpio_request_pin(struct gpio_chip *gc, unsigned offset)
 311 {
 312         struct pca9532_data *data = gpiochip_get_data(gc);
 313         struct pca9532_led *led = &data->leds[offset];
 314
 315         if (led->type == PCA9532_TYPE_GPIO)
 316                 return 0;
 317
 318         return -EBUSY;
 319 }
 320
 321 static void pca9532_gpio_set_value(struct gpio_chip *gc, unsigned offset, int val)
 322 {
 323         struct pca9532_data *data = gpiochip_get_data(gc);
 324         struct pca9532_led *led = &data->leds[offset];
 325
 326         if (val)
 327                 led->state = PCA9532_ON;
 328         else
 329                 led->state = PCA9532_OFF;
 330
 331         pca9532_setled(led);
 332 }
 333
 334 static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
 335 {
 336         struct pca9532_data *data = gpiochip_get_data(gc);
 337         unsigned char reg;
 338
 339         reg = i2c_smbus_read_byte_data(data->client, PCA9532_REG_INPUT(offset));
 340
 341         return !!(reg & (1 << (offset % 8)));
 342 }
 343
 344 static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
 345 {
 346         /* To use as input ensure pin is not driven */
 347         pca9532_gpio_set_value(gc, offset, 0);
 348
 349         return 0;
 350 }
 351
 352 static int pca9532_gpio_direction_output(struct gpio_chip *gc, unsigned offset, int val)
 353 {
 354         pca9532_gpio_set_value(gc, offset, val);
 355
 356         return 0;
 357 }
 358 #endif /* CONFIG_LEDS_PCA9532_GPIO */
 359
 360 static void pca9532_destroy_devices(struct pca9532_data *data, int n_devs)
 361 {
 362         int i = n_devs;
 363
 364         while (--i >= 0) {
 365                 switch (data->leds[i].type) {
 366                 case PCA9532_TYPE_NONE:
 367                 case PCA9532_TYPE_GPIO:
 368                         break;
 369                 case PCA9532_TYPE_LED:
 370                         led_classdev_unregister(&data->leds[i].ldev);
 371                         break;
 372                 case PCA9532_TYPE_N2100_BEEP:
 373                         if (data->idev != NULL) {
 374                                 cancel_work_sync(&data->work);
 375                                 data->idev = NULL;
 376                         }
 377                         break;
 378                 }
 379         }
 380
 381 #ifdef CONFIG_LEDS_PCA9532_GPIO
 382         if (data->gpio.parent)
 383                 gpiochip_remove(&data->gpio);
 384 #endif
 385 }
 386
 387 static int pca9532_configure(struct i2c_client *client,
 388         struct pca9532_data *data, struct pca9532_platform_data *pdata)
 389 {
 390         int i, err = 0;
 391         int gpios = 0;
 392         u8 maxleds = data->chip_info->num_leds;
 393
 394         for (i = 0; i < 2; i++) {
 395                 data->pwm[i] = pdata->pwm[i];
 396                 data->psc[i] = pdata->psc[i];
 397                 i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(maxleds, i),
 398                         data->pwm[i]);
 399                 i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(maxleds, i),
 400                         data->psc[i]);
 401         }
 402
 403         data->hw_blink = true;
 404         for (i = 0; i < data->chip_info->num_leds; i++) {
 405                 struct pca9532_led *led = &data->leds[i];
 406                 struct pca9532_led *pled = &pdata->leds[i];
 407                 led->client = client;
 408                 led->id = i;
 409                 led->type = pled->type;
 410                 switch (led->type) {
 411                 case PCA9532_TYPE_NONE:
 412                         break;
 413                 case PCA9532_TYPE_GPIO:
 414                         gpios++;
 415                         break;
 416                 case PCA9532_TYPE_LED:
 417                         if (pled->state == PCA9532_KEEP)
 418                                 led->state = pca9532_getled(led);
 419                         else
 420                                 led->state = pled->state;
 421                         led->name = pled->name;
 422                         led->ldev.name = led->name;
 423                         led->ldev.default_trigger = pled->default_trigger;
 424                         led->ldev.brightness = LED_OFF;
 425                         led->ldev.brightness_set_blocking =
 426                                                 pca9532_set_brightness;
 427                         led->ldev.blink_set = pca9532_set_blink;
 428                         err = led_classdev_register(&client->dev, &led->ldev);
 429                         if (err < 0) {
 430                                 dev_err(&client->dev,
 431                                         "couldn't register LED %s\n",
 432                                         led->name);
 433                                 goto exit;
 434                         }
 435                         pca9532_setled(led);
 436                         break;
 437                 case PCA9532_TYPE_N2100_BEEP:
 438                         /* PWM1 is reserved for beeper so blink will not use hardware */
 439                         data->hw_blink = false;
 440                         BUG_ON(data->idev);
 441                         led->state = PCA9532_PWM1;
 442                         pca9532_setled(led);
 443                         data->idev = devm_input_allocate_device(&client->dev);
 444                         if (data->idev == NULL) {
 445                                 err = -ENOMEM;
 446                                 goto exit;
 447                         }
 448                         data->idev->name = pled->name;
 449                         data->idev->phys = "i2c/pca9532";
 450                         data->idev->id.bustype = BUS_HOST;
 451                         data->idev->id.vendor = 0x001f;
 452                         data->idev->id.product = 0x0001;
 453                         data->idev->id.version = 0x0100;
 454                         data->idev->evbit[0] = BIT_MASK(EV_SND);
 455                         data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
 456                                                 BIT_MASK(SND_TONE);
 457                         data->idev->event = pca9532_event;
 458                         input_set_drvdata(data->idev, data);
 459                         INIT_WORK(&data->work, pca9532_input_work);
 460                         err = input_register_device(data->idev);
 461                         if (err) {
 462                                 cancel_work_sync(&data->work);
 463                                 data->idev = NULL;
 464                                 goto exit;
 465                         }
 466                         break;
 467                 }
 468         }
 469
 470 #ifdef CONFIG_LEDS_PCA9532_GPIO
 471         if (gpios) {
 472                 data->gpio.label = "gpio-pca9532";
 473                 data->gpio.direction_input = pca9532_gpio_direction_input;
 474                 data->gpio.direction_output = pca9532_gpio_direction_output;
 475                 data->gpio.set = pca9532_gpio_set_value;
 476                 data->gpio.get = pca9532_gpio_get_value;
 477                 data->gpio.request = pca9532_gpio_request_pin;
 478                 data->gpio.can_sleep = 1;
 479                 data->gpio.base = pdata->gpio_base;
 480                 data->gpio.ngpio = data->chip_info->num_leds;
 481                 data->gpio.parent = &client->dev;
 482                 data->gpio.owner = THIS_MODULE;
 483
 484                 err = gpiochip_add_data(&data->gpio, data);
 485                 if (err) {
 486                         /* Use data->gpio.dev as a flag for freeing gpiochip */
 487                         data->gpio.parent = NULL;
 488                         dev_warn(&client->dev, "could not add gpiochip\n");
 489                 } else {
 490                         dev_info(&client->dev, "gpios %i...%i\n",
 491                                 data->gpio.base, data->gpio.base +
 492                                 data->gpio.ngpio - 1);
 493                 }
 494         }
 495 #endif
 496
 497         return 0;
 498
 499 exit:
 500         pca9532_destroy_devices(data, i);
 501         return err;
 502 }
 503
 504 static struct pca9532_platform_data *
 505 pca9532_of_populate_pdata(struct device *dev, struct device_node *np)
 506 {
 507         struct pca9532_platform_data *pdata;
 508         int devid, maxleds;
 509         int i = 0;
 510         const char *state;
 511
 512         devid = (int)(uintptr_t)of_device_get_match_data(dev);
 513         maxleds = pca9532_chip_info_tbl[devid].num_leds;
 514
 515         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 516         if (!pdata)
 517                 return ERR_PTR(-ENOMEM);
 518
 519         pdata->gpio_base = -1;
 520
 521         of_property_read_u8_array(np, "nxp,pwm", &pdata->pwm[PCA9532_PWM_ID_0],
 522                                   ARRAY_SIZE(pdata->pwm));
 523         of_property_read_u8_array(np, "nxp,psc", &pdata->psc[PCA9532_PWM_ID_0],
 524                                   ARRAY_SIZE(pdata->psc));
 525
 526         for_each_available_child_of_node_scoped(np, child) {
 527                 if (of_property_read_string(child, "label",
 528                                             &pdata->leds[i].name))
 529                         pdata->leds[i].name = child->name;
 530                 of_property_read_u32(child, "type", &pdata->leds[i].type);
 531                 of_property_read_string(child, "linux,default-trigger",
 532                                         &pdata->leds[i].default_trigger);
 533                 if (!of_property_read_string(child, "default-state", &state)) {
 534                         if (!strcmp(state, "on"))
 535                                 pdata->leds[i].state = PCA9532_ON;
 536                         else if (!strcmp(state, "keep"))
 537                                 pdata->leds[i].state = PCA9532_KEEP;
 538                 }
 539                 if (++i >= maxleds)
 540                         break;
 541         }
 542
 543         return pdata;
 544 }
 545
 546 static int pca9532_probe(struct i2c_client *client)
 547 {
 548         const struct i2c_device_id *id = i2c_client_get_device_id(client);
 549         int devid;
 550         struct pca9532_data *data = i2c_get_clientdata(client);
 551         struct pca9532_platform_data *pca9532_pdata =
 552                         dev_get_platdata(&client->dev);
 553         struct device_node *np = dev_of_node(&client->dev);
 554
 555         if (!pca9532_pdata) {
 556                 if (np) {
 557                         pca9532_pdata =
 558                                 pca9532_of_populate_pdata(&client->dev, np);
 559                         if (IS_ERR(pca9532_pdata))
 560                                 return PTR_ERR(pca9532_pdata);
 561                 } else {
 562                         dev_err(&client->dev, "no platform data\n");
 563                         return -EINVAL;
 564                 }
 565                 devid = (int)(uintptr_t)of_device_get_match_data(&client->dev);
 566         } else {
 567                 devid = id->driver_data;
 568         }
 569
 570         if (!i2c_check_functionality(client->adapter,
 571                 I2C_FUNC_SMBUS_BYTE_DATA))
 572                 return -EIO;
 573
 574         data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
 575         if (!data)
 576                 return -ENOMEM;
 577
 578         data->chip_info = &pca9532_chip_info_tbl[devid];
 579
 580         dev_info(&client->dev, "setting platform data\n");
 581         i2c_set_clientdata(client, data);
 582         data->client = client;
 583         mutex_init(&data->update_lock);
 584
 585         return pca9532_configure(client, data, pca9532_pdata);
 586 }
 587
 588 static void pca9532_remove(struct i2c_client *client)
 589 {
 590         struct pca9532_data *data = i2c_get_clientdata(client);
 591
 592         pca9532_destroy_devices(data, data->chip_info->num_leds);
 593 }
 594
 595 module_i2c_driver(pca9532_driver);
 596
 597 MODULE_AUTHOR("Riku Voipio");
 598 MODULE_LICENSE("GPL");
 599 MODULE_DESCRIPTION("PCA 9532 LED dimmer");