1 // SPDX-License-Identifier: GPL-2.0+ 2 // Driver for Awinic AW2013 3-channel LED driver 3 4 #include <linux/i2c.h> 5 #include <linux/leds.h> 6 #include <linux/module.h> 7 #include <linux/regulator/consumer.h> 8 #include <linux/mutex.h> 9 #include <linux/of.h> 10 #include <linux/regmap.h> 11 12 #define AW2013_MAX_LEDS 3 13 14 /* Reset and ID register */ 15 #define AW2013_RSTR 0x00 16 #define AW2013_RSTR_RESET 0x55 17 #define AW2013_RSTR_CHIP_ID 0x33 18 19 /* Global control register */ 20 #define AW2013_GCR 0x01 21 #define AW2013_GCR_ENABLE BIT(0) 22 23 /* LED channel enable register */ 24 #define AW2013_LCTR 0x30 25 #define AW2013_LCTR_LE(x) BIT((x)) 26 27 /* LED channel control registers */ 28 #define AW2013_LCFG(x) (0x31 + (x)) 29 #define AW2013_LCFG_IMAX_MASK (BIT(0) | BIT(1)) // Should be 0-3 30 #define AW2013_LCFG_MD BIT(4) 31 #define AW2013_LCFG_FI BIT(5) 32 #define AW2013_LCFG_FO BIT(6) 33 34 /* LED channel PWM registers */ 35 #define AW2013_REG_PWM(x) (0x34 + (x)) 36 37 /* LED channel timing registers */ 38 #define AW2013_LEDT0(x) (0x37 + (x) * 3) 39 #define AW2013_LEDT0_T1(x) ((x) << 4) // Should be 0-7 40 #define AW2013_LEDT0_T2(x) (x) // Should be 0-5 41 42 #define AW2013_LEDT1(x) (0x38 + (x) * 3) 43 #define AW2013_LEDT1_T3(x) ((x) << 4) // Should be 0-7 44 #define AW2013_LEDT1_T4(x) (x) // Should be 0-7 45 46 #define AW2013_LEDT2(x) (0x39 + (x) * 3) 47 #define AW2013_LEDT2_T0(x) ((x) << 4) // Should be 0-8 48 #define AW2013_LEDT2_REPEAT(x) (x) // Should be 0-15 49 50 #define AW2013_REG_MAX 0x77 51 52 #define AW2013_TIME_STEP 130 /* ms */ 53 54 struct aw2013; 55 56 struct aw2013_led { 57 struct aw2013 *chip; 58 struct led_classdev cdev; 59 u32 num; 60 unsigned int imax; 61 }; 62 63 struct aw2013 { 64 struct mutex mutex; /* held when writing to registers */ 65 struct regulator_bulk_data regulators[2]; 66 struct i2c_client *client; 67 struct aw2013_led leds[AW2013_MAX_LEDS]; 68 struct regmap *regmap; 69 int num_leds; 70 bool enabled; 71 }; 72 73 static int aw2013_chip_init(struct aw2013 *chip) 74 { 75 int i, ret; 76 77 ret = regmap_write(chip->regmap, AW2013_GCR, AW2013_GCR_ENABLE); 78 if (ret) { 79 dev_err(&chip->client->dev, "Failed to enable the chip: %d\n", 80 ret); 81 return ret; 82 } 83 84 for (i = 0; i < chip->num_leds; i++) { 85 ret = regmap_update_bits(chip->regmap, 86 AW2013_LCFG(chip->leds[i].num), 87 AW2013_LCFG_IMAX_MASK, 88 chip->leds[i].imax); 89 if (ret) { 90 dev_err(&chip->client->dev, 91 "Failed to set maximum current for led %d: %d\n", 92 chip->leds[i].num, ret); 93 return ret; 94 } 95 } 96 97 return ret; 98 } 99 100 static void aw2013_chip_disable(struct aw2013 *chip) 101 { 102 int ret; 103 104 if (!chip->enabled) 105 return; 106 107 regmap_write(chip->regmap, AW2013_GCR, 0); 108 109 ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators), 110 chip->regulators); 111 if (ret) { 112 dev_err(&chip->client->dev, 113 "Failed to disable regulators: %d\n", ret); 114 return; 115 } 116 117 chip->enabled = false; 118 } 119 120 static int aw2013_chip_enable(struct aw2013 *chip) 121 { 122 int ret; 123 124 if (chip->enabled) 125 return 0; 126 127 ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators), 128 chip->regulators); 129 if (ret) { 130 dev_err(&chip->client->dev, 131 "Failed to enable regulators: %d\n", ret); 132 return ret; 133 } 134 chip->enabled = true; 135 136 ret = aw2013_chip_init(chip); 137 if (ret) 138 aw2013_chip_disable(chip); 139 140 return ret; 141 } 142 143 static bool aw2013_chip_in_use(struct aw2013 *chip) 144 { 145 int i; 146 147 for (i = 0; i < chip->num_leds; i++) 148 if (chip->leds[i].cdev.brightness) 149 return true; 150 151 return false; 152 } 153 154 static int aw2013_brightness_set(struct led_classdev *cdev, 155 enum led_brightness brightness) 156 { 157 struct aw2013_led *led = container_of(cdev, struct aw2013_led, cdev); 158 int ret, num; 159 160 mutex_lock(&led->chip->mutex); 161 162 if (aw2013_chip_in_use(led->chip)) { 163 ret = aw2013_chip_enable(led->chip); 164 if (ret) 165 goto error; 166 } 167 168 num = led->num; 169 170 ret = regmap_write(led->chip->regmap, AW2013_REG_PWM(num), brightness); 171 if (ret) 172 goto error; 173 174 if (brightness) { 175 ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR, 176 AW2013_LCTR_LE(num), 0xFF); 177 } else { 178 ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR, 179 AW2013_LCTR_LE(num), 0); 180 if (ret) 181 goto error; 182 ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num), 183 AW2013_LCFG_MD, 0); 184 } 185 if (ret) 186 goto error; 187 188 if (!aw2013_chip_in_use(led->chip)) 189 aw2013_chip_disable(led->chip); 190 191 error: 192 mutex_unlock(&led->chip->mutex); 193 194 return ret; 195 } 196 197 static int aw2013_blink_set(struct led_classdev *cdev, 198 unsigned long *delay_on, unsigned long *delay_off) 199 { 200 struct aw2013_led *led = container_of(cdev, struct aw2013_led, cdev); 201 int ret, num = led->num; 202 unsigned long off = 0, on = 0; 203 204 /* If no blink specified, default to 1 Hz. */ 205 if (!*delay_off && !*delay_on) { 206 *delay_off = 500; 207 *delay_on = 500; 208 } 209 210 if (!led->cdev.brightness) { 211 led->cdev.brightness = LED_FULL; 212 ret = aw2013_brightness_set(&led->cdev, led->cdev.brightness); 213 if (ret) 214 return ret; 215 } 216 217 /* Never on - just set to off */ 218 if (!*delay_on) { 219 led->cdev.brightness = LED_OFF; 220 return aw2013_brightness_set(&led->cdev, LED_OFF); 221 } 222 223 mutex_lock(&led->chip->mutex); 224 225 /* Never off - brightness is already set, disable blinking */ 226 if (!*delay_off) { 227 ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num), 228 AW2013_LCFG_MD, 0); 229 goto out; 230 } 231 232 /* Convert into values the HW will understand. */ 233 off = min(5, ilog2((*delay_off - 1) / AW2013_TIME_STEP) + 1); 234 on = min(7, ilog2((*delay_on - 1) / AW2013_TIME_STEP) + 1); 235 236 *delay_off = BIT(off) * AW2013_TIME_STEP; 237 *delay_on = BIT(on) * AW2013_TIME_STEP; 238 239 /* Set timings */ 240 ret = regmap_write(led->chip->regmap, 241 AW2013_LEDT0(num), AW2013_LEDT0_T2(on)); 242 if (ret) 243 goto out; 244 ret = regmap_write(led->chip->regmap, 245 AW2013_LEDT1(num), AW2013_LEDT1_T4(off)); 246 if (ret) 247 goto out; 248 249 /* Finally, enable the LED */ 250 ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num), 251 AW2013_LCFG_MD, 0xFF); 252 if (ret) 253 goto out; 254 255 ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR, 256 AW2013_LCTR_LE(num), 0xFF); 257 258 out: 259 mutex_unlock(&led->chip->mutex); 260 261 return ret; 262 } 263 264 static int aw2013_probe_dt(struct aw2013 *chip) 265 { 266 struct device_node *np = dev_of_node(&chip->client->dev); 267 int count, ret = 0, i = 0; 268 struct aw2013_led *led; 269 270 count = of_get_available_child_count(np); 271 if (!count || count > AW2013_MAX_LEDS) 272 return -EINVAL; 273 274 regmap_write(chip->regmap, AW2013_RSTR, AW2013_RSTR_RESET); 275 276 for_each_available_child_of_node_scoped(np, child) { 277 struct led_init_data init_data = {}; 278 u32 source; 279 u32 imax; 280 281 ret = of_property_read_u32(child, "reg", &source); 282 if (ret != 0 || source >= AW2013_MAX_LEDS) { 283 dev_err(&chip->client->dev, 284 "Couldn't read LED address: %d\n", ret); 285 count--; 286 continue; 287 } 288 289 led = &chip->leds[i]; 290 led->num = source; 291 led->chip = chip; 292 init_data.fwnode = of_fwnode_handle(child); 293 294 if (!of_property_read_u32(child, "led-max-microamp", &imax)) { 295 led->imax = min_t(u32, imax / 5000, 3); 296 } else { 297 led->imax = 1; // 5mA 298 dev_info(&chip->client->dev, 299 "DT property led-max-microamp is missing\n"); 300 } 301 302 led->cdev.brightness_set_blocking = aw2013_brightness_set; 303 led->cdev.blink_set = aw2013_blink_set; 304 305 ret = devm_led_classdev_register_ext(&chip->client->dev, 306 &led->cdev, &init_data); 307 if (ret < 0) 308 return ret; 309 310 i++; 311 } 312 313 if (!count) 314 return -EINVAL; 315 316 chip->num_leds = i; 317 318 return 0; 319 } 320 321 static void aw2013_chip_disable_action(void *data) 322 { 323 aw2013_chip_disable(data); 324 } 325 326 static const struct regmap_config aw2013_regmap_config = { 327 .reg_bits = 8, 328 .val_bits = 8, 329 .max_register = AW2013_REG_MAX, 330 }; 331 332 static int aw2013_probe(struct i2c_client *client) 333 { 334 struct aw2013 *chip; 335 int ret; 336 unsigned int chipid; 337 338 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); 339 if (!chip) 340 return -ENOMEM; 341 342 ret = devm_mutex_init(&client->dev, &chip->mutex); 343 if (ret) 344 return ret; 345 346 mutex_lock(&chip->mutex); 347 348 chip->client = client; 349 i2c_set_clientdata(client, chip); 350 351 chip->regmap = devm_regmap_init_i2c(client, &aw2013_regmap_config); 352 if (IS_ERR(chip->regmap)) { 353 ret = PTR_ERR(chip->regmap); 354 dev_err(&client->dev, "Failed to allocate register map: %d\n", 355 ret); 356 goto error; 357 } 358 359 chip->regulators[0].supply = "vcc"; 360 chip->regulators[1].supply = "vio"; 361 ret = devm_regulator_bulk_get(&client->dev, 362 ARRAY_SIZE(chip->regulators), 363 chip->regulators); 364 if (ret < 0) { 365 if (ret != -EPROBE_DEFER) 366 dev_err(&client->dev, 367 "Failed to request regulators: %d\n", ret); 368 goto error; 369 } 370 371 ret = regulator_bulk_enable(ARRAY_SIZE(chip->regulators), 372 chip->regulators); 373 if (ret) { 374 dev_err(&client->dev, 375 "Failed to enable regulators: %d\n", ret); 376 goto error; 377 } 378 379 ret = regmap_read(chip->regmap, AW2013_RSTR, &chipid); 380 if (ret) { 381 dev_err(&client->dev, "Failed to read chip ID: %d\n", 382 ret); 383 goto error_reg; 384 } 385 386 if (chipid != AW2013_RSTR_CHIP_ID) { 387 dev_err(&client->dev, "Chip reported wrong ID: %x\n", 388 chipid); 389 ret = -ENODEV; 390 goto error_reg; 391 } 392 393 ret = devm_add_action(&client->dev, aw2013_chip_disable_action, chip); 394 if (ret) 395 goto error_reg; 396 397 ret = aw2013_probe_dt(chip); 398 if (ret < 0) 399 goto error_reg; 400 401 ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators), 402 chip->regulators); 403 if (ret) { 404 dev_err(&client->dev, 405 "Failed to disable regulators: %d\n", ret); 406 goto error; 407 } 408 409 mutex_unlock(&chip->mutex); 410 411 return 0; 412 413 error_reg: 414 regulator_bulk_disable(ARRAY_SIZE(chip->regulators), 415 chip->regulators); 416 417 error: 418 mutex_unlock(&chip->mutex); 419 return ret; 420 } 421 422 static const struct of_device_id aw2013_match_table[] = { 423 { .compatible = "awinic,aw2013", }, 424 { /* sentinel */ }, 425 }; 426 427 MODULE_DEVICE_TABLE(of, aw2013_match_table); 428 429 static struct i2c_driver aw2013_driver = { 430 .driver = { 431 .name = "leds-aw2013", 432 .of_match_table = aw2013_match_table, 433 }, 434 .probe = aw2013_probe, 435 }; 436 437 module_i2c_driver(aw2013_driver); 438 439 MODULE_AUTHOR("Nikita Travkin <nikitos.tr@gmail.com>"); 440 MODULE_DESCRIPTION("AW2013 LED driver"); 441 MODULE_LICENSE("GPL v2"); 442