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/slab.h> 36 #include <linux/of.h> 37 #include <linux/platform_data/leds-pca963x.h> 38 39 /* LED select registers determine the source that drives LED outputs */ 40 #define PCA963X_LED_OFF 0x0 /* LED driver off */ 41 #define PCA963X_LED_ON 0x1 /* LED driver on */ 42 #define PCA963X_LED_PWM 0x2 /* Controlled through PWM */ 43 #define PCA963X_LED_GRP_PWM 0x3 /* Controlled through PWM/GRPPWM */ 44 45 #define PCA963X_MODE2_DMBLNK 0x20 /* Enable blinking */ 46 47 #define PCA963X_MODE1 0x00 48 #define PCA963X_MODE2 0x01 49 #define PCA963X_PWM_BASE 0x02 50 51 enum pca963x_type { 52 pca9633, 53 pca9634, 54 pca9635, 55 }; 56 57 struct pca963x_chipdef { 58 u8 grppwm; 59 u8 grpfreq; 60 u8 ledout_base; 61 int n_leds; 62 }; 63 64 static struct pca963x_chipdef pca963x_chipdefs[] = { 65 [pca9633] = { 66 .grppwm = 0x6, 67 .grpfreq = 0x7, 68 .ledout_base = 0x8, 69 .n_leds = 4, 70 }, 71 [pca9634] = { 72 .grppwm = 0xa, 73 .grpfreq = 0xb, 74 .ledout_base = 0xc, 75 .n_leds = 8, 76 }, 77 [pca9635] = { 78 .grppwm = 0x12, 79 .grpfreq = 0x13, 80 .ledout_base = 0x14, 81 .n_leds = 16, 82 }, 83 }; 84 85 /* Total blink period in milliseconds */ 86 #define PCA963X_BLINK_PERIOD_MIN 42 87 #define PCA963X_BLINK_PERIOD_MAX 10667 88 89 static const struct i2c_device_id pca963x_id[] = { 90 { "pca9632", pca9633 }, 91 { "pca9633", pca9633 }, 92 { "pca9634", pca9634 }, 93 { "pca9635", pca9635 }, 94 { } 95 }; 96 MODULE_DEVICE_TABLE(i2c, pca963x_id); 97 98 struct pca963x_led; 99 100 struct pca963x { 101 struct pca963x_chipdef *chipdef; 102 struct mutex mutex; 103 struct i2c_client *client; 104 struct pca963x_led *leds; 105 }; 106 107 struct pca963x_led { 108 struct pca963x *chip; 109 struct led_classdev led_cdev; 110 int led_num; /* 0 .. 15 potentially */ 111 char name[32]; 112 u8 gdc; 113 u8 gfrq; 114 }; 115 116 static int pca963x_brightness(struct pca963x_led *pca963x, 117 enum led_brightness brightness) 118 { 119 u8 ledout_addr = pca963x->chip->chipdef->ledout_base 120 + (pca963x->led_num / 4); 121 u8 ledout; 122 int shift = 2 * (pca963x->led_num % 4); 123 u8 mask = 0x3 << shift; 124 int ret; 125 126 mutex_lock(&pca963x->chip->mutex); 127 ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr); 128 switch (brightness) { 129 case LED_FULL: 130 ret = i2c_smbus_write_byte_data(pca963x->chip->client, 131 ledout_addr, 132 (ledout & ~mask) | (PCA963X_LED_ON << shift)); 133 break; 134 case LED_OFF: 135 ret = i2c_smbus_write_byte_data(pca963x->chip->client, 136 ledout_addr, ledout & ~mask); 137 break; 138 default: 139 ret = i2c_smbus_write_byte_data(pca963x->chip->client, 140 PCA963X_PWM_BASE + pca963x->led_num, 141 brightness); 142 if (ret < 0) 143 goto unlock; 144 ret = i2c_smbus_write_byte_data(pca963x->chip->client, 145 ledout_addr, 146 (ledout & ~mask) | (PCA963X_LED_PWM << shift)); 147 break; 148 } 149 unlock: 150 mutex_unlock(&pca963x->chip->mutex); 151 return ret; 152 } 153 154 static void pca963x_blink(struct pca963x_led *pca963x) 155 { 156 u8 ledout_addr = pca963x->chip->chipdef->ledout_base + 157 (pca963x->led_num / 4); 158 u8 ledout; 159 u8 mode2 = i2c_smbus_read_byte_data(pca963x->chip->client, 160 PCA963X_MODE2); 161 int shift = 2 * (pca963x->led_num % 4); 162 u8 mask = 0x3 << shift; 163 164 i2c_smbus_write_byte_data(pca963x->chip->client, 165 pca963x->chip->chipdef->grppwm, pca963x->gdc); 166 167 i2c_smbus_write_byte_data(pca963x->chip->client, 168 pca963x->chip->chipdef->grpfreq, pca963x->gfrq); 169 170 if (!(mode2 & PCA963X_MODE2_DMBLNK)) 171 i2c_smbus_write_byte_data(pca963x->chip->client, PCA963X_MODE2, 172 mode2 | PCA963X_MODE2_DMBLNK); 173 174 mutex_lock(&pca963x->chip->mutex); 175 ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr); 176 if ((ledout & mask) != (PCA963X_LED_GRP_PWM << shift)) 177 i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr, 178 (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift)); 179 mutex_unlock(&pca963x->chip->mutex); 180 } 181 182 static int pca963x_led_set(struct led_classdev *led_cdev, 183 enum led_brightness value) 184 { 185 struct pca963x_led *pca963x; 186 187 pca963x = container_of(led_cdev, struct pca963x_led, led_cdev); 188 189 return pca963x_brightness(pca963x, value); 190 } 191 192 static int pca963x_blink_set(struct led_classdev *led_cdev, 193 unsigned long *delay_on, unsigned long *delay_off) 194 { 195 struct pca963x_led *pca963x; 196 unsigned long time_on, time_off, period; 197 u8 gdc, gfrq; 198 199 pca963x = container_of(led_cdev, struct pca963x_led, led_cdev); 200 201 time_on = *delay_on; 202 time_off = *delay_off; 203 204 /* If both zero, pick reasonable defaults of 500ms each */ 205 if (!time_on && !time_off) { 206 time_on = 500; 207 time_off = 500; 208 } 209 210 period = time_on + time_off; 211 212 /* If period not supported by hardware, default to someting sane. */ 213 if ((period < PCA963X_BLINK_PERIOD_MIN) || 214 (period > PCA963X_BLINK_PERIOD_MAX)) { 215 time_on = 500; 216 time_off = 500; 217 period = time_on + time_off; 218 } 219 220 /* 221 * From manual: duty cycle = (GDC / 256) -> 222 * (time_on / period) = (GDC / 256) -> 223 * GDC = ((time_on * 256) / period) 224 */ 225 gdc = (time_on * 256) / period; 226 227 /* 228 * From manual: period = ((GFRQ + 1) / 24) in seconds. 229 * So, period (in ms) = (((GFRQ + 1) / 24) * 1000) -> 230 * GFRQ = ((period * 24 / 1000) - 1) 231 */ 232 gfrq = (period * 24 / 1000) - 1; 233 234 pca963x->gdc = gdc; 235 pca963x->gfrq = gfrq; 236 237 pca963x_blink(pca963x); 238 239 *delay_on = time_on; 240 *delay_off = time_off; 241 242 return 0; 243 } 244 245 #if IS_ENABLED(CONFIG_OF) 246 static struct pca963x_platform_data * 247 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip) 248 { 249 struct device_node *np = client->dev.of_node, *child; 250 struct pca963x_platform_data *pdata; 251 struct led_info *pca963x_leds; 252 int count; 253 254 count = of_get_child_count(np); 255 if (!count || count > chip->n_leds) 256 return ERR_PTR(-ENODEV); 257 258 pca963x_leds = devm_kzalloc(&client->dev, 259 sizeof(struct led_info) * chip->n_leds, GFP_KERNEL); 260 if (!pca963x_leds) 261 return ERR_PTR(-ENOMEM); 262 263 for_each_child_of_node(np, child) { 264 struct led_info led = {}; 265 u32 reg; 266 int res; 267 268 res = of_property_read_u32(child, "reg", ®); 269 if ((res != 0) || (reg >= chip->n_leds)) 270 continue; 271 led.name = 272 of_get_property(child, "label", NULL) ? : child->name; 273 led.default_trigger = 274 of_get_property(child, "linux,default-trigger", NULL); 275 pca963x_leds[reg] = led; 276 } 277 pdata = devm_kzalloc(&client->dev, 278 sizeof(struct pca963x_platform_data), GFP_KERNEL); 279 if (!pdata) 280 return ERR_PTR(-ENOMEM); 281 282 pdata->leds.leds = pca963x_leds; 283 pdata->leds.num_leds = chip->n_leds; 284 285 /* default to open-drain unless totem pole (push-pull) is specified */ 286 if (of_property_read_bool(np, "nxp,totem-pole")) 287 pdata->outdrv = PCA963X_TOTEM_POLE; 288 else 289 pdata->outdrv = PCA963X_OPEN_DRAIN; 290 291 /* default to software blinking unless hardware blinking is specified */ 292 if (of_property_read_bool(np, "nxp,hw-blink")) 293 pdata->blink_type = PCA963X_HW_BLINK; 294 else 295 pdata->blink_type = PCA963X_SW_BLINK; 296 297 return pdata; 298 } 299 300 static const struct of_device_id of_pca963x_match[] = { 301 { .compatible = "nxp,pca9632", }, 302 { .compatible = "nxp,pca9633", }, 303 { .compatible = "nxp,pca9634", }, 304 { .compatible = "nxp,pca9635", }, 305 {}, 306 }; 307 MODULE_DEVICE_TABLE(of, of_pca963x_match); 308 #else 309 static struct pca963x_platform_data * 310 pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip) 311 { 312 return ERR_PTR(-ENODEV); 313 } 314 #endif 315 316 static int pca963x_probe(struct i2c_client *client, 317 const struct i2c_device_id *id) 318 { 319 struct pca963x *pca963x_chip; 320 struct pca963x_led *pca963x; 321 struct pca963x_platform_data *pdata; 322 struct pca963x_chipdef *chip; 323 int i, err; 324 325 chip = &pca963x_chipdefs[id->driver_data]; 326 pdata = dev_get_platdata(&client->dev); 327 328 if (!pdata) { 329 pdata = pca963x_dt_init(client, chip); 330 if (IS_ERR(pdata)) { 331 dev_warn(&client->dev, "could not parse configuration\n"); 332 pdata = NULL; 333 } 334 } 335 336 if (pdata && (pdata->leds.num_leds < 1 || 337 pdata->leds.num_leds > chip->n_leds)) { 338 dev_err(&client->dev, "board info must claim 1-%d LEDs", 339 chip->n_leds); 340 return -EINVAL; 341 } 342 343 pca963x_chip = devm_kzalloc(&client->dev, sizeof(*pca963x_chip), 344 GFP_KERNEL); 345 if (!pca963x_chip) 346 return -ENOMEM; 347 pca963x = devm_kzalloc(&client->dev, chip->n_leds * sizeof(*pca963x), 348 GFP_KERNEL); 349 if (!pca963x) 350 return -ENOMEM; 351 352 i2c_set_clientdata(client, pca963x_chip); 353 354 mutex_init(&pca963x_chip->mutex); 355 pca963x_chip->chipdef = chip; 356 pca963x_chip->client = client; 357 pca963x_chip->leds = pca963x; 358 359 /* Turn off LEDs by default*/ 360 for (i = 0; i < chip->n_leds / 4; i++) 361 i2c_smbus_write_byte_data(client, chip->ledout_base + i, 0x00); 362 363 for (i = 0; i < chip->n_leds; i++) { 364 pca963x[i].led_num = i; 365 pca963x[i].chip = pca963x_chip; 366 367 /* Platform data can specify LED names and default triggers */ 368 if (pdata && i < pdata->leds.num_leds) { 369 if (pdata->leds.leds[i].name) 370 snprintf(pca963x[i].name, 371 sizeof(pca963x[i].name), "pca963x:%s", 372 pdata->leds.leds[i].name); 373 if (pdata->leds.leds[i].default_trigger) 374 pca963x[i].led_cdev.default_trigger = 375 pdata->leds.leds[i].default_trigger; 376 } 377 if (!pdata || i >= pdata->leds.num_leds || 378 !pdata->leds.leds[i].name) 379 snprintf(pca963x[i].name, sizeof(pca963x[i].name), 380 "pca963x:%d:%.2x:%d", client->adapter->nr, 381 client->addr, i); 382 383 pca963x[i].led_cdev.name = pca963x[i].name; 384 pca963x[i].led_cdev.brightness_set_blocking = pca963x_led_set; 385 386 if (pdata && pdata->blink_type == PCA963X_HW_BLINK) 387 pca963x[i].led_cdev.blink_set = pca963x_blink_set; 388 389 err = led_classdev_register(&client->dev, &pca963x[i].led_cdev); 390 if (err < 0) 391 goto exit; 392 } 393 394 /* Disable LED all-call address and set normal mode */ 395 i2c_smbus_write_byte_data(client, PCA963X_MODE1, 0x00); 396 397 if (pdata) { 398 /* Configure output: open-drain or totem pole (push-pull) */ 399 if (pdata->outdrv == PCA963X_OPEN_DRAIN) 400 i2c_smbus_write_byte_data(client, PCA963X_MODE2, 0x01); 401 else 402 i2c_smbus_write_byte_data(client, PCA963X_MODE2, 0x05); 403 } 404 405 return 0; 406 407 exit: 408 while (i--) 409 led_classdev_unregister(&pca963x[i].led_cdev); 410 411 return err; 412 } 413 414 static int pca963x_remove(struct i2c_client *client) 415 { 416 struct pca963x *pca963x = i2c_get_clientdata(client); 417 int i; 418 419 for (i = 0; i < pca963x->chipdef->n_leds; i++) 420 led_classdev_unregister(&pca963x->leds[i].led_cdev); 421 422 return 0; 423 } 424 425 static struct i2c_driver pca963x_driver = { 426 .driver = { 427 .name = "leds-pca963x", 428 .of_match_table = of_match_ptr(of_pca963x_match), 429 }, 430 .probe = pca963x_probe, 431 .remove = pca963x_remove, 432 .id_table = pca963x_id, 433 }; 434 435 module_i2c_driver(pca963x_driver); 436 437 MODULE_AUTHOR("Peter Meerwald <p.meerwald@bct-electronic.com>"); 438 MODULE_DESCRIPTION("PCA963X LED driver"); 439 MODULE_LICENSE("GPL v2"); 440