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/module.h> 29 #include <linux/delay.h> 30 #include <linux/string.h> 31 #include <linux/ctype.h> 32 #include <linux/leds.h> 33 #include <linux/err.h> 34 #include <linux/i2c.h> 35 #include <linux/workqueue.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 }; 64 65 static struct pca963x_chipdef pca963x_chipdefs[] = { 66 [pca9633] = { 67 .grppwm = 0x6, 68 .grpfreq = 0x7, 69 .ledout_base = 0x8, 70 .n_leds = 4, 71 }, 72 [pca9634] = { 73 .grppwm = 0xa, 74 .grpfreq = 0xb, 75 .ledout_base = 0xc, 76 .n_leds = 8, 77 }, 78 [pca9635] = { 79 .grppwm = 0x12, 80 .grpfreq = 0x13, 81 .ledout_base = 0x14, 82 .n_leds = 16, 83 }, 84 }; 85 86 /* Total blink period in milliseconds */ 87 #define PCA963X_BLINK_PERIOD_MIN 42 88 #define PCA963X_BLINK_PERIOD_MAX 10667 89 90 static const struct i2c_device_id pca963x_id[] = { 91 { "pca9632", pca9633 }, 92 { "pca9633", pca9633 }, 93 { "pca9634", pca9634 }, 94 { "pca9635", pca9635 }, 95 { } 96 }; 97 MODULE_DEVICE_TABLE(i2c, pca963x_id); 98 99 enum pca963x_cmd { 100 BRIGHTNESS_SET, 101 BLINK_SET, 102 }; 103 104 struct pca963x_led; 105 106 struct pca963x { 107 struct pca963x_chipdef *chipdef; 108 struct mutex mutex; 109 struct i2c_client *client; 110 struct pca963x_led *leds; 111 }; 112 113 struct pca963x_led { 114 struct pca963x *chip; 115 struct work_struct work; 116 enum led_brightness brightness; 117 struct led_classdev led_cdev; 118 int led_num; /* 0 .. 15 potentially */ 119 enum pca963x_cmd cmd; 120 char name[32]; 121 u8 gdc; 122 u8 gfrq; 123 }; 124 125 static void pca963x_brightness_work(struct pca963x_led *pca963x) 126 { 127 u8 ledout_addr = pca963x->chip->chipdef->ledout_base 128 + (pca963x->led_num / 4); 129 u8 ledout; 130 int shift = 2 * (pca963x->led_num % 4); 131 u8 mask = 0x3 << shift; 132 133 mutex_lock(&pca963x->chip->mutex); 134 ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr); 135 switch (pca963x->brightness) { 136 case LED_FULL: 137 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr, 138 (ledout & ~mask) | (PCA963X_LED_ON << shift)); 139 break; 140 case LED_OFF: 141 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr, 142 ledout & ~mask); 143 break; 144 default: 145 i2c_smbus_write_byte_data(pca963x->chip->client, 146 PCA963X_PWM_BASE + pca963x->led_num, 147 pca963x->brightness); 148 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr, 149 (ledout & ~mask) | (PCA963X_LED_PWM << shift)); 150 break; 151 } 152 mutex_unlock(&pca963x->chip->mutex); 153 } 154 155 static void pca963x_blink_work(struct pca963x_led *pca963x) 156 { 157 u8 ledout_addr = pca963x->chip->chipdef->ledout_base + 158 (pca963x->led_num / 4); 159 u8 ledout; 160 u8 mode2 = i2c_smbus_read_byte_data(pca963x->chip->client, 161 PCA963X_MODE2); 162 int shift = 2 * (pca963x->led_num % 4); 163 u8 mask = 0x3 << shift; 164 165 i2c_smbus_write_byte_data(pca963x->chip->client, 166 pca963x->chip->chipdef->grppwm, pca963x->gdc); 167 168 i2c_smbus_write_byte_data(pca963x->chip->client, 169 pca963x->chip->chipdef->grpfreq, pca963x->gfrq); 170 171 if (!(mode2 & PCA963X_MODE2_DMBLNK)) 172 i2c_smbus_write_byte_data(pca963x->chip->client, PCA963X_MODE2, 173 mode2 | PCA963X_MODE2_DMBLNK); 174 175 mutex_lock(&pca963x->chip->mutex); 176 ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr); 177 if ((ledout & mask) != (PCA963X_LED_GRP_PWM << shift)) 178 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr, 179 (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift)); 180 mutex_unlock(&pca963x->chip->mutex); 181 } 182 183 static void pca963x_work(struct work_struct *work) 184 { 185 struct pca963x_led *pca963x = container_of(work, 186 struct pca963x_led, work); 187 188 switch (pca963x->cmd) { 189 case BRIGHTNESS_SET: 190 pca963x_brightness_work(pca963x); 191 break; 192 case BLINK_SET: 193 pca963x_blink_work(pca963x); 194 break; 195 } 196 } 197 198 static void pca963x_led_set(struct led_classdev *led_cdev, 199 enum led_brightness value) 200 { 201 struct pca963x_led *pca963x; 202 203 pca963x = container_of(led_cdev, struct pca963x_led, led_cdev); 204 205 pca963x->cmd = BRIGHTNESS_SET; 206 pca963x->brightness = value; 207 208 /* 209 * Must use workqueue for the actual I/O since I2C operations 210 * can sleep. 211 */ 212 schedule_work(&pca963x->work); 213 } 214 215 static int pca963x_blink_set(struct led_classdev *led_cdev, 216 unsigned long *delay_on, unsigned long *delay_off) 217 { 218 struct pca963x_led *pca963x; 219 unsigned long time_on, time_off, period; 220 u8 gdc, gfrq; 221 222 pca963x = container_of(led_cdev, struct pca963x_led, led_cdev); 223 224 time_on = *delay_on; 225 time_off = *delay_off; 226 227 /* If both zero, pick reasonable defaults of 500ms each */ 228 if (!time_on && !time_off) { 229 time_on = 500; 230 time_off = 500; 231 } 232 233 period = time_on + time_off; 234 235 /* If period not supported by hardware, default to someting sane. */ 236 if ((period < PCA963X_BLINK_PERIOD_MIN) || 237 (period > PCA963X_BLINK_PERIOD_MAX)) { 238 time_on = 500; 239 time_off = 500; 240 period = time_on + time_off; 241 } 242 243 /* 244 * From manual: duty cycle = (GDC / 256) -> 245 * (time_on / period) = (GDC / 256) -> 246 * GDC = ((time_on * 256) / period) 247 */ 248 gdc = (time_on * 256) / period; 249 250 /* 251 * From manual: period = ((GFRQ + 1) / 24) in seconds. 252 * So, period (in ms) = (((GFRQ + 1) / 24) * 1000) -> 253 * GFRQ = ((period * 24 / 1000) - 1) 254 */ 255 gfrq = (period * 24 / 1000) - 1; 256 257 pca963x->cmd = BLINK_SET; 258 pca963x->gdc = gdc; 259 pca963x->gfrq = gfrq; 260 261 /* 262 * Must use workqueue for the actual I/O since I2C operations 263 * can sleep. 264 */ 265 schedule_work(&pca963x->work); 266 267 *delay_on = time_on; 268 *delay_off = time_off; 269 270 return 0; 271 } 272 273 #if IS_ENABLED(CONFIG_OF) 274 static struct pca963x_platform_data * 275 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip) 276 { 277 struct device_node *np = client->dev.of_node, *child; 278 struct pca963x_platform_data *pdata; 279 struct led_info *pca963x_leds; 280 int count; 281 282 count = of_get_child_count(np); 283 if (!count || count > chip->n_leds) 284 return ERR_PTR(-ENODEV); 285 286 pca963x_leds = devm_kzalloc(&client->dev, 287 sizeof(struct led_info) * chip->n_leds, GFP_KERNEL); 288 if (!pca963x_leds) 289 return ERR_PTR(-ENOMEM); 290 291 for_each_child_of_node(np, child) { 292 struct led_info led = {}; 293 u32 reg; 294 int res; 295 296 res = of_property_read_u32(child, "reg", ®); 297 if ((res != 0) || (reg >= chip->n_leds)) 298 continue; 299 led.name = 300 of_get_property(child, "label", NULL) ? : child->name; 301 led.default_trigger = 302 of_get_property(child, "linux,default-trigger", NULL); 303 pca963x_leds[reg] = led; 304 } 305 pdata = devm_kzalloc(&client->dev, 306 sizeof(struct pca963x_platform_data), GFP_KERNEL); 307 if (!pdata) 308 return ERR_PTR(-ENOMEM); 309 310 pdata->leds.leds = pca963x_leds; 311 pdata->leds.num_leds = chip->n_leds; 312 313 /* default to open-drain unless totem pole (push-pull) is specified */ 314 if (of_property_read_bool(np, "nxp,totem-pole")) 315 pdata->outdrv = PCA963X_TOTEM_POLE; 316 else 317 pdata->outdrv = PCA963X_OPEN_DRAIN; 318 319 /* default to software blinking unless hardware blinking is specified */ 320 if (of_property_read_bool(np, "nxp,hw-blink")) 321 pdata->blink_type = PCA963X_HW_BLINK; 322 else 323 pdata->blink_type = PCA963X_SW_BLINK; 324 325 return pdata; 326 } 327 328 static const struct of_device_id of_pca963x_match[] = { 329 { .compatible = "nxp,pca9632", }, 330 { .compatible = "nxp,pca9633", }, 331 { .compatible = "nxp,pca9634", }, 332 { .compatible = "nxp,pca9635", }, 333 {}, 334 }; 335 #else 336 static struct pca963x_platform_data * 337 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip) 338 { 339 return ERR_PTR(-ENODEV); 340 } 341 #endif 342 343 static int pca963x_probe(struct i2c_client *client, 344 const struct i2c_device_id *id) 345 { 346 struct pca963x *pca963x_chip; 347 struct pca963x_led *pca963x; 348 struct pca963x_platform_data *pdata; 349 struct pca963x_chipdef *chip; 350 int i, err; 351 352 chip = &pca963x_chipdefs[id->driver_data]; 353 pdata = dev_get_platdata(&client->dev); 354 355 if (!pdata) { 356 pdata = pca963x_dt_init(client, chip); 357 if (IS_ERR(pdata)) { 358 dev_warn(&client->dev, "could not parse configuration\n"); 359 pdata = NULL; 360 } 361 } 362 363 if (pdata && (pdata->leds.num_leds < 1 || 364 pdata->leds.num_leds > chip->n_leds)) { 365 dev_err(&client->dev, "board info must claim 1-%d LEDs", 366 chip->n_leds); 367 return -EINVAL; 368 } 369 370 pca963x_chip = devm_kzalloc(&client->dev, sizeof(*pca963x_chip), 371 GFP_KERNEL); 372 if (!pca963x_chip) 373 return -ENOMEM; 374 pca963x = devm_kzalloc(&client->dev, chip->n_leds * sizeof(*pca963x), 375 GFP_KERNEL); 376 if (!pca963x) 377 return -ENOMEM; 378 379 i2c_set_clientdata(client, pca963x_chip); 380 381 mutex_init(&pca963x_chip->mutex); 382 pca963x_chip->chipdef = chip; 383 pca963x_chip->client = client; 384 pca963x_chip->leds = pca963x; 385 386 /* Turn off LEDs by default*/ 387 for (i = 0; i < chip->n_leds / 4; i++) 388 i2c_smbus_write_byte_data(client, chip->ledout_base + i, 0x00); 389 390 for (i = 0; i < chip->n_leds; i++) { 391 pca963x[i].led_num = i; 392 pca963x[i].chip = pca963x_chip; 393 394 /* Platform data can specify LED names and default triggers */ 395 if (pdata && i < pdata->leds.num_leds) { 396 if (pdata->leds.leds[i].name) 397 snprintf(pca963x[i].name, 398 sizeof(pca963x[i].name), "pca963x:%s", 399 pdata->leds.leds[i].name); 400 if (pdata->leds.leds[i].default_trigger) 401 pca963x[i].led_cdev.default_trigger = 402 pdata->leds.leds[i].default_trigger; 403 } 404 if (!pdata || i >= pdata->leds.num_leds || 405 !pdata->leds.leds[i].name) 406 snprintf(pca963x[i].name, sizeof(pca963x[i].name), 407 "pca963x:%d:%.2x:%d", client->adapter->nr, 408 client->addr, i); 409 410 pca963x[i].led_cdev.name = pca963x[i].name; 411 pca963x[i].led_cdev.brightness_set = pca963x_led_set; 412 413 if (pdata && pdata->blink_type == PCA963X_HW_BLINK) 414 pca963x[i].led_cdev.blink_set = pca963x_blink_set; 415 416 INIT_WORK(&pca963x[i].work, pca963x_work); 417 418 err = led_classdev_register(&client->dev, &pca963x[i].led_cdev); 419 if (err < 0) 420 goto exit; 421 } 422 423 /* Disable LED all-call address and set normal mode */ 424 i2c_smbus_write_byte_data(client, PCA963X_MODE1, 0x00); 425 426 if (pdata) { 427 /* Configure output: open-drain or totem pole (push-pull) */ 428 if (pdata->outdrv == PCA963X_OPEN_DRAIN) 429 i2c_smbus_write_byte_data(client, PCA963X_MODE2, 0x01); 430 else 431 i2c_smbus_write_byte_data(client, PCA963X_MODE2, 0x05); 432 } 433 434 return 0; 435 436 exit: 437 while (i--) { 438 led_classdev_unregister(&pca963x[i].led_cdev); 439 cancel_work_sync(&pca963x[i].work); 440 } 441 442 return err; 443 } 444 445 static int pca963x_remove(struct i2c_client *client) 446 { 447 struct pca963x *pca963x = i2c_get_clientdata(client); 448 int i; 449 450 for (i = 0; i < pca963x->chipdef->n_leds; i++) { 451 led_classdev_unregister(&pca963x->leds[i].led_cdev); 452 cancel_work_sync(&pca963x->leds[i].work); 453 } 454 455 return 0; 456 } 457 458 static struct i2c_driver pca963x_driver = { 459 .driver = { 460 .name = "leds-pca963x", 461 .owner = THIS_MODULE, 462 .of_match_table = of_match_ptr(of_pca963x_match), 463 }, 464 .probe = pca963x_probe, 465 .remove = pca963x_remove, 466 .id_table = pca963x_id, 467 }; 468 469 module_i2c_driver(pca963x_driver); 470 471 MODULE_AUTHOR("Peter Meerwald <p.meerwald@bct-electronic.com>"); 472 MODULE_DESCRIPTION("PCA963X LED driver"); 473 MODULE_LICENSE("GPL v2"); 474