1 /* 2 * Copyright 2011 bct electronic GmbH 3 * Copyright 2013 Qtechnology/AS 4 * 5 * Author: Peter Meerwald <p.meerwald@bct-electronic.com> 6 * Author: Ricardo Ribalda <ricardo.ribalda@gmail.com> 7 * 8 * Based on leds-pca955x.c 9 * 10 * This file is subject to the terms and conditions of version 2 of 11 * the GNU General Public License. See the file COPYING in the main 12 * directory of this archive for more details. 13 * 14 * LED driver for the PCA9633 I2C LED driver (7-bit slave address 0x62) 15 * LED driver for the PCA9634/5 I2C LED driver (7-bit slave address set by hw.) 16 * 17 * Note that hardware blinking violates the leds infrastructure driver 18 * interface since the hardware only supports blinking all LEDs with the 19 * same delay_on/delay_off rates. That is, only the LEDs that are set to 20 * blink will actually blink but all LEDs that are set to blink will blink 21 * in identical fashion. The delay_on/delay_off values of the last LED 22 * that is set to blink will be used for all of the blinking LEDs. 23 * Hardware blinking is disabled by default but can be enabled by setting 24 * the 'blink_type' member in the platform_data struct to 'PCA963X_HW_BLINK' 25 * or by adding the 'nxp,hw-blink' property to the DTS. 26 */ 27 28 #include <linux/acpi.h> 29 #include <linux/module.h> 30 #include <linux/delay.h> 31 #include <linux/string.h> 32 #include <linux/ctype.h> 33 #include <linux/leds.h> 34 #include <linux/err.h> 35 #include <linux/i2c.h> 36 #include <linux/slab.h> 37 #include <linux/of.h> 38 #include <linux/platform_data/leds-pca963x.h> 39 40 /* LED select registers determine the source that drives LED outputs */ 41 #define PCA963X_LED_OFF 0x0 /* LED driver off */ 42 #define PCA963X_LED_ON 0x1 /* LED driver on */ 43 #define PCA963X_LED_PWM 0x2 /* Controlled through PWM */ 44 #define PCA963X_LED_GRP_PWM 0x3 /* Controlled through PWM/GRPPWM */ 45 46 #define PCA963X_MODE2_DMBLNK 0x20 /* Enable blinking */ 47 48 #define PCA963X_MODE1 0x00 49 #define PCA963X_MODE2 0x01 50 #define PCA963X_PWM_BASE 0x02 51 52 enum pca963x_type { 53 pca9633, 54 pca9634, 55 pca9635, 56 }; 57 58 struct pca963x_chipdef { 59 u8 grppwm; 60 u8 grpfreq; 61 u8 ledout_base; 62 int n_leds; 63 unsigned int scaling; 64 }; 65 66 static struct pca963x_chipdef pca963x_chipdefs[] = { 67 [pca9633] = { 68 .grppwm = 0x6, 69 .grpfreq = 0x7, 70 .ledout_base = 0x8, 71 .n_leds = 4, 72 }, 73 [pca9634] = { 74 .grppwm = 0xa, 75 .grpfreq = 0xb, 76 .ledout_base = 0xc, 77 .n_leds = 8, 78 }, 79 [pca9635] = { 80 .grppwm = 0x12, 81 .grpfreq = 0x13, 82 .ledout_base = 0x14, 83 .n_leds = 16, 84 }, 85 }; 86 87 /* Total blink period in milliseconds */ 88 #define PCA963X_BLINK_PERIOD_MIN 42 89 #define PCA963X_BLINK_PERIOD_MAX 10667 90 91 static const struct i2c_device_id pca963x_id[] = { 92 { "pca9632", pca9633 }, 93 { "pca9633", pca9633 }, 94 { "pca9634", pca9634 }, 95 { "pca9635", pca9635 }, 96 { } 97 }; 98 MODULE_DEVICE_TABLE(i2c, pca963x_id); 99 100 static const struct acpi_device_id pca963x_acpi_ids[] = { 101 { "PCA9632", pca9633 }, 102 { "PCA9633", pca9633 }, 103 { "PCA9634", pca9634 }, 104 { "PCA9635", pca9635 }, 105 { } 106 }; 107 MODULE_DEVICE_TABLE(acpi, pca963x_acpi_ids); 108 109 struct pca963x_led; 110 111 struct pca963x { 112 struct pca963x_chipdef *chipdef; 113 struct mutex mutex; 114 struct i2c_client *client; 115 struct pca963x_led *leds; 116 unsigned long leds_on; 117 }; 118 119 struct pca963x_led { 120 struct pca963x *chip; 121 struct led_classdev led_cdev; 122 int led_num; /* 0 .. 15 potentially */ 123 char name[32]; 124 u8 gdc; 125 u8 gfrq; 126 }; 127 128 static int pca963x_brightness(struct pca963x_led *pca963x, 129 enum led_brightness brightness) 130 { 131 u8 ledout_addr = pca963x->chip->chipdef->ledout_base 132 + (pca963x->led_num / 4); 133 u8 ledout; 134 int shift = 2 * (pca963x->led_num % 4); 135 u8 mask = 0x3 << shift; 136 int ret; 137 138 ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr); 139 switch (brightness) { 140 case LED_FULL: 141 ret = i2c_smbus_write_byte_data(pca963x->chip->client, 142 ledout_addr, 143 (ledout & ~mask) | (PCA963X_LED_ON << shift)); 144 break; 145 case LED_OFF: 146 ret = i2c_smbus_write_byte_data(pca963x->chip->client, 147 ledout_addr, ledout & ~mask); 148 break; 149 default: 150 ret = i2c_smbus_write_byte_data(pca963x->chip->client, 151 PCA963X_PWM_BASE + pca963x->led_num, 152 brightness); 153 if (ret < 0) 154 return ret; 155 ret = i2c_smbus_write_byte_data(pca963x->chip->client, 156 ledout_addr, 157 (ledout & ~mask) | (PCA963X_LED_PWM << shift)); 158 break; 159 } 160 161 return ret; 162 } 163 164 static void pca963x_blink(struct pca963x_led *pca963x) 165 { 166 u8 ledout_addr = pca963x->chip->chipdef->ledout_base + 167 (pca963x->led_num / 4); 168 u8 ledout; 169 u8 mode2 = i2c_smbus_read_byte_data(pca963x->chip->client, 170 PCA963X_MODE2); 171 int shift = 2 * (pca963x->led_num % 4); 172 u8 mask = 0x3 << shift; 173 174 i2c_smbus_write_byte_data(pca963x->chip->client, 175 pca963x->chip->chipdef->grppwm, pca963x->gdc); 176 177 i2c_smbus_write_byte_data(pca963x->chip->client, 178 pca963x->chip->chipdef->grpfreq, pca963x->gfrq); 179 180 if (!(mode2 & PCA963X_MODE2_DMBLNK)) 181 i2c_smbus_write_byte_data(pca963x->chip->client, PCA963X_MODE2, 182 mode2 | PCA963X_MODE2_DMBLNK); 183 184 mutex_lock(&pca963x->chip->mutex); 185 ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr); 186 if ((ledout & mask) != (PCA963X_LED_GRP_PWM << shift)) 187 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr, 188 (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift)); 189 mutex_unlock(&pca963x->chip->mutex); 190 } 191 192 static int pca963x_power_state(struct pca963x_led *pca963x) 193 { 194 unsigned long *leds_on = &pca963x->chip->leds_on; 195 unsigned long cached_leds = pca963x->chip->leds_on; 196 197 if (pca963x->led_cdev.brightness) 198 set_bit(pca963x->led_num, leds_on); 199 else 200 clear_bit(pca963x->led_num, leds_on); 201 202 if (!(*leds_on) != !cached_leds) 203 return i2c_smbus_write_byte_data(pca963x->chip->client, 204 PCA963X_MODE1, *leds_on ? 0 : BIT(4)); 205 206 return 0; 207 } 208 209 static int pca963x_led_set(struct led_classdev *led_cdev, 210 enum led_brightness value) 211 { 212 struct pca963x_led *pca963x; 213 int ret; 214 215 pca963x = container_of(led_cdev, struct pca963x_led, led_cdev); 216 217 mutex_lock(&pca963x->chip->mutex); 218 219 ret = pca963x_brightness(pca963x, value); 220 if (ret < 0) 221 goto unlock; 222 ret = pca963x_power_state(pca963x); 223 224 unlock: 225 mutex_unlock(&pca963x->chip->mutex); 226 return ret; 227 } 228 229 static unsigned int pca963x_period_scale(struct pca963x_led *pca963x, 230 unsigned int val) 231 { 232 unsigned int scaling = pca963x->chip->chipdef->scaling; 233 234 return scaling ? DIV_ROUND_CLOSEST(val * scaling, 1000) : val; 235 } 236 237 static int pca963x_blink_set(struct led_classdev *led_cdev, 238 unsigned long *delay_on, unsigned long *delay_off) 239 { 240 struct pca963x_led *pca963x; 241 unsigned long time_on, time_off, period; 242 u8 gdc, gfrq; 243 244 pca963x = container_of(led_cdev, struct pca963x_led, led_cdev); 245 246 time_on = *delay_on; 247 time_off = *delay_off; 248 249 /* If both zero, pick reasonable defaults of 500ms each */ 250 if (!time_on && !time_off) { 251 time_on = 500; 252 time_off = 500; 253 } 254 255 period = pca963x_period_scale(pca963x, time_on + time_off); 256 257 /* If period not supported by hardware, default to someting sane. */ 258 if ((period < PCA963X_BLINK_PERIOD_MIN) || 259 (period > PCA963X_BLINK_PERIOD_MAX)) { 260 time_on = 500; 261 time_off = 500; 262 period = pca963x_period_scale(pca963x, 1000); 263 } 264 265 /* 266 * From manual: duty cycle = (GDC / 256) -> 267 * (time_on / period) = (GDC / 256) -> 268 * GDC = ((time_on * 256) / period) 269 */ 270 gdc = (pca963x_period_scale(pca963x, time_on) * 256) / period; 271 272 /* 273 * From manual: period = ((GFRQ + 1) / 24) in seconds. 274 * So, period (in ms) = (((GFRQ + 1) / 24) * 1000) -> 275 * GFRQ = ((period * 24 / 1000) - 1) 276 */ 277 gfrq = (period * 24 / 1000) - 1; 278 279 pca963x->gdc = gdc; 280 pca963x->gfrq = gfrq; 281 282 pca963x_blink(pca963x); 283 284 *delay_on = time_on; 285 *delay_off = time_off; 286 287 return 0; 288 } 289 290 #if IS_ENABLED(CONFIG_OF) 291 static struct pca963x_platform_data * 292 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip) 293 { 294 struct device_node *np = client->dev.of_node, *child; 295 struct pca963x_platform_data *pdata; 296 struct led_info *pca963x_leds; 297 int count; 298 299 count = of_get_child_count(np); 300 if (!count || count > chip->n_leds) 301 return ERR_PTR(-ENODEV); 302 303 pca963x_leds = devm_kzalloc(&client->dev, 304 sizeof(struct led_info) * chip->n_leds, GFP_KERNEL); 305 if (!pca963x_leds) 306 return ERR_PTR(-ENOMEM); 307 308 for_each_child_of_node(np, child) { 309 struct led_info led = {}; 310 u32 reg; 311 int res; 312 313 res = of_property_read_u32(child, "reg", ®); 314 if ((res != 0) || (reg >= chip->n_leds)) 315 continue; 316 led.name = 317 of_get_property(child, "label", NULL) ? : child->name; 318 led.default_trigger = 319 of_get_property(child, "linux,default-trigger", NULL); 320 pca963x_leds[reg] = led; 321 } 322 pdata = devm_kzalloc(&client->dev, 323 sizeof(struct pca963x_platform_data), GFP_KERNEL); 324 if (!pdata) 325 return ERR_PTR(-ENOMEM); 326 327 pdata->leds.leds = pca963x_leds; 328 pdata->leds.num_leds = chip->n_leds; 329 330 /* default to open-drain unless totem pole (push-pull) is specified */ 331 if (of_property_read_bool(np, "nxp,totem-pole")) 332 pdata->outdrv = PCA963X_TOTEM_POLE; 333 else 334 pdata->outdrv = PCA963X_OPEN_DRAIN; 335 336 /* default to software blinking unless hardware blinking is specified */ 337 if (of_property_read_bool(np, "nxp,hw-blink")) 338 pdata->blink_type = PCA963X_HW_BLINK; 339 else 340 pdata->blink_type = PCA963X_SW_BLINK; 341 342 if (of_property_read_u32(np, "nxp,period-scale", &chip->scaling)) 343 chip->scaling = 1000; 344 345 return pdata; 346 } 347 348 static const struct of_device_id of_pca963x_match[] = { 349 { .compatible = "nxp,pca9632", }, 350 { .compatible = "nxp,pca9633", }, 351 { .compatible = "nxp,pca9634", }, 352 { .compatible = "nxp,pca9635", }, 353 {}, 354 }; 355 MODULE_DEVICE_TABLE(of, of_pca963x_match); 356 #else 357 static struct pca963x_platform_data * 358 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip) 359 { 360 return ERR_PTR(-ENODEV); 361 } 362 #endif 363 364 static int pca963x_probe(struct i2c_client *client, 365 const struct i2c_device_id *id) 366 { 367 struct pca963x *pca963x_chip; 368 struct pca963x_led *pca963x; 369 struct pca963x_platform_data *pdata; 370 struct pca963x_chipdef *chip; 371 int i, err; 372 373 if (id) { 374 chip = &pca963x_chipdefs[id->driver_data]; 375 } else { 376 const struct acpi_device_id *acpi_id; 377 378 acpi_id = acpi_match_device(pca963x_acpi_ids, &client->dev); 379 if (!acpi_id) 380 return -ENODEV; 381 chip = &pca963x_chipdefs[acpi_id->driver_data]; 382 } 383 pdata = dev_get_platdata(&client->dev); 384 385 if (!pdata) { 386 pdata = pca963x_dt_init(client, chip); 387 if (IS_ERR(pdata)) { 388 dev_warn(&client->dev, "could not parse configuration\n"); 389 pdata = NULL; 390 } 391 } 392 393 if (pdata && (pdata->leds.num_leds < 1 || 394 pdata->leds.num_leds > chip->n_leds)) { 395 dev_err(&client->dev, "board info must claim 1-%d LEDs", 396 chip->n_leds); 397 return -EINVAL; 398 } 399 400 pca963x_chip = devm_kzalloc(&client->dev, sizeof(*pca963x_chip), 401 GFP_KERNEL); 402 if (!pca963x_chip) 403 return -ENOMEM; 404 pca963x = devm_kzalloc(&client->dev, chip->n_leds * sizeof(*pca963x), 405 GFP_KERNEL); 406 if (!pca963x) 407 return -ENOMEM; 408 409 i2c_set_clientdata(client, pca963x_chip); 410 411 mutex_init(&pca963x_chip->mutex); 412 pca963x_chip->chipdef = chip; 413 pca963x_chip->client = client; 414 pca963x_chip->leds = pca963x; 415 416 /* Turn off LEDs by default*/ 417 for (i = 0; i < chip->n_leds / 4; i++) 418 i2c_smbus_write_byte_data(client, chip->ledout_base + i, 0x00); 419 420 for (i = 0; i < chip->n_leds; i++) { 421 pca963x[i].led_num = i; 422 pca963x[i].chip = pca963x_chip; 423 424 /* Platform data can specify LED names and default triggers */ 425 if (pdata && i < pdata->leds.num_leds) { 426 if (pdata->leds.leds[i].name) 427 snprintf(pca963x[i].name, 428 sizeof(pca963x[i].name), "pca963x:%s", 429 pdata->leds.leds[i].name); 430 if (pdata->leds.leds[i].default_trigger) 431 pca963x[i].led_cdev.default_trigger = 432 pdata->leds.leds[i].default_trigger; 433 } 434 if (!pdata || i >= pdata->leds.num_leds || 435 !pdata->leds.leds[i].name) 436 snprintf(pca963x[i].name, sizeof(pca963x[i].name), 437 "pca963x:%d:%.2x:%d", client->adapter->nr, 438 client->addr, i); 439 440 pca963x[i].led_cdev.name = pca963x[i].name; 441 pca963x[i].led_cdev.brightness_set_blocking = pca963x_led_set; 442 443 if (pdata && pdata->blink_type == PCA963X_HW_BLINK) 444 pca963x[i].led_cdev.blink_set = pca963x_blink_set; 445 446 err = led_classdev_register(&client->dev, &pca963x[i].led_cdev); 447 if (err < 0) 448 goto exit; 449 } 450 451 /* Disable LED all-call address, and power down initially */ 452 i2c_smbus_write_byte_data(client, PCA963X_MODE1, BIT(4)); 453 454 if (pdata) { 455 /* Configure output: open-drain or totem pole (push-pull) */ 456 if (pdata->outdrv == PCA963X_OPEN_DRAIN) 457 i2c_smbus_write_byte_data(client, PCA963X_MODE2, 0x01); 458 else 459 i2c_smbus_write_byte_data(client, PCA963X_MODE2, 0x05); 460 } 461 462 return 0; 463 464 exit: 465 while (i--) 466 led_classdev_unregister(&pca963x[i].led_cdev); 467 468 return err; 469 } 470 471 static int pca963x_remove(struct i2c_client *client) 472 { 473 struct pca963x *pca963x = i2c_get_clientdata(client); 474 int i; 475 476 for (i = 0; i < pca963x->chipdef->n_leds; i++) 477 led_classdev_unregister(&pca963x->leds[i].led_cdev); 478 479 return 0; 480 } 481 482 static struct i2c_driver pca963x_driver = { 483 .driver = { 484 .name = "leds-pca963x", 485 .of_match_table = of_match_ptr(of_pca963x_match), 486 .acpi_match_table = ACPI_PTR(pca963x_acpi_ids), 487 }, 488 .probe = pca963x_probe, 489 .remove = pca963x_remove, 490 .id_table = pca963x_id, 491 }; 492 493 module_i2c_driver(pca963x_driver); 494 495 MODULE_AUTHOR("Peter Meerwald <p.meerwald@bct-electronic.com>"); 496 MODULE_DESCRIPTION("PCA963X LED driver"); 497 MODULE_LICENSE("GPL v2"); 498