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 *vcc_regulator; 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_disable(chip->vcc_regulator); 110 if (ret) { 111 dev_err(&chip->client->dev, 112 "Failed to disable regulator: %d\n", ret); 113 return; 114 } 115 116 chip->enabled = false; 117 } 118 119 static int aw2013_chip_enable(struct aw2013 *chip) 120 { 121 int ret; 122 123 if (chip->enabled) 124 return 0; 125 126 ret = regulator_enable(chip->vcc_regulator); 127 if (ret) { 128 dev_err(&chip->client->dev, 129 "Failed to enable regulator: %d\n", ret); 130 return ret; 131 } 132 chip->enabled = true; 133 134 ret = aw2013_chip_init(chip); 135 if (ret) 136 aw2013_chip_disable(chip); 137 138 return ret; 139 } 140 141 static bool aw2013_chip_in_use(struct aw2013 *chip) 142 { 143 int i; 144 145 for (i = 0; i < chip->num_leds; i++) 146 if (chip->leds[i].cdev.brightness) 147 return true; 148 149 return false; 150 } 151 152 static int aw2013_brightness_set(struct led_classdev *cdev, 153 enum led_brightness brightness) 154 { 155 struct aw2013_led *led = container_of(cdev, struct aw2013_led, cdev); 156 int ret, num; 157 158 mutex_lock(&led->chip->mutex); 159 160 if (aw2013_chip_in_use(led->chip)) { 161 ret = aw2013_chip_enable(led->chip); 162 if (ret) 163 goto error; 164 } 165 166 num = led->num; 167 168 ret = regmap_write(led->chip->regmap, AW2013_REG_PWM(num), brightness); 169 if (ret) 170 goto error; 171 172 if (brightness) { 173 ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR, 174 AW2013_LCTR_LE(num), 0xFF); 175 } else { 176 ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR, 177 AW2013_LCTR_LE(num), 0); 178 if (ret) 179 goto error; 180 ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num), 181 AW2013_LCFG_MD, 0); 182 } 183 if (ret) 184 goto error; 185 186 if (!aw2013_chip_in_use(led->chip)) 187 aw2013_chip_disable(led->chip); 188 189 error: 190 mutex_unlock(&led->chip->mutex); 191 192 return ret; 193 } 194 195 static int aw2013_blink_set(struct led_classdev *cdev, 196 unsigned long *delay_on, unsigned long *delay_off) 197 { 198 struct aw2013_led *led = container_of(cdev, struct aw2013_led, cdev); 199 int ret, num = led->num; 200 unsigned long off = 0, on = 0; 201 202 /* If no blink specified, default to 1 Hz. */ 203 if (!*delay_off && !*delay_on) { 204 *delay_off = 500; 205 *delay_on = 500; 206 } 207 208 if (!led->cdev.brightness) { 209 led->cdev.brightness = LED_FULL; 210 ret = aw2013_brightness_set(&led->cdev, led->cdev.brightness); 211 if (ret) 212 return ret; 213 } 214 215 /* Never on - just set to off */ 216 if (!*delay_on) { 217 led->cdev.brightness = LED_OFF; 218 return aw2013_brightness_set(&led->cdev, LED_OFF); 219 } 220 221 mutex_lock(&led->chip->mutex); 222 223 /* Never off - brightness is already set, disable blinking */ 224 if (!*delay_off) { 225 ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num), 226 AW2013_LCFG_MD, 0); 227 goto out; 228 } 229 230 /* Convert into values the HW will understand. */ 231 off = min(5, ilog2((*delay_off - 1) / AW2013_TIME_STEP) + 1); 232 on = min(7, ilog2((*delay_on - 1) / AW2013_TIME_STEP) + 1); 233 234 *delay_off = BIT(off) * AW2013_TIME_STEP; 235 *delay_on = BIT(on) * AW2013_TIME_STEP; 236 237 /* Set timings */ 238 ret = regmap_write(led->chip->regmap, 239 AW2013_LEDT0(num), AW2013_LEDT0_T2(on)); 240 if (ret) 241 goto out; 242 ret = regmap_write(led->chip->regmap, 243 AW2013_LEDT1(num), AW2013_LEDT1_T4(off)); 244 if (ret) 245 goto out; 246 247 /* Finally, enable the LED */ 248 ret = regmap_update_bits(led->chip->regmap, AW2013_LCFG(num), 249 AW2013_LCFG_MD, 0xFF); 250 if (ret) 251 goto out; 252 253 ret = regmap_update_bits(led->chip->regmap, AW2013_LCTR, 254 AW2013_LCTR_LE(num), 0xFF); 255 256 out: 257 mutex_unlock(&led->chip->mutex); 258 259 return ret; 260 } 261 262 static int aw2013_probe_dt(struct aw2013 *chip) 263 { 264 struct device_node *np = dev_of_node(&chip->client->dev), *child; 265 int count, ret = 0, i = 0; 266 struct aw2013_led *led; 267 268 count = of_get_available_child_count(np); 269 if (!count || count > AW2013_MAX_LEDS) 270 return -EINVAL; 271 272 regmap_write(chip->regmap, AW2013_RSTR, AW2013_RSTR_RESET); 273 274 for_each_available_child_of_node(np, child) { 275 struct led_init_data init_data = {}; 276 u32 source; 277 u32 imax; 278 279 ret = of_property_read_u32(child, "reg", &source); 280 if (ret != 0 || source >= AW2013_MAX_LEDS) { 281 dev_err(&chip->client->dev, 282 "Couldn't read LED address: %d\n", ret); 283 count--; 284 continue; 285 } 286 287 led = &chip->leds[i]; 288 led->num = source; 289 led->chip = chip; 290 init_data.fwnode = of_fwnode_handle(child); 291 292 if (!of_property_read_u32(child, "led-max-microamp", &imax)) { 293 led->imax = min_t(u32, imax / 5000, 3); 294 } else { 295 led->imax = 1; // 5mA 296 dev_info(&chip->client->dev, 297 "DT property led-max-microamp is missing\n"); 298 } 299 300 led->cdev.brightness_set_blocking = aw2013_brightness_set; 301 led->cdev.blink_set = aw2013_blink_set; 302 303 ret = devm_led_classdev_register_ext(&chip->client->dev, 304 &led->cdev, &init_data); 305 if (ret < 0) { 306 of_node_put(child); 307 return ret; 308 } 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 const struct regmap_config aw2013_regmap_config = { 322 .reg_bits = 8, 323 .val_bits = 8, 324 .max_register = AW2013_REG_MAX, 325 }; 326 327 static int aw2013_probe(struct i2c_client *client) 328 { 329 struct aw2013 *chip; 330 int ret; 331 unsigned int chipid; 332 333 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); 334 if (!chip) 335 return -ENOMEM; 336 337 mutex_init(&chip->mutex); 338 mutex_lock(&chip->mutex); 339 340 chip->client = client; 341 i2c_set_clientdata(client, chip); 342 343 chip->regmap = devm_regmap_init_i2c(client, &aw2013_regmap_config); 344 if (IS_ERR(chip->regmap)) { 345 ret = PTR_ERR(chip->regmap); 346 dev_err(&client->dev, "Failed to allocate register map: %d\n", 347 ret); 348 goto error; 349 } 350 351 chip->vcc_regulator = devm_regulator_get(&client->dev, "vcc"); 352 ret = PTR_ERR_OR_ZERO(chip->vcc_regulator); 353 if (ret) { 354 if (ret != -EPROBE_DEFER) 355 dev_err(&client->dev, 356 "Failed to request regulator: %d\n", ret); 357 goto error; 358 } 359 360 ret = regulator_enable(chip->vcc_regulator); 361 if (ret) { 362 dev_err(&client->dev, 363 "Failed to enable regulator: %d\n", ret); 364 goto error; 365 } 366 367 ret = regmap_read(chip->regmap, AW2013_RSTR, &chipid); 368 if (ret) { 369 dev_err(&client->dev, "Failed to read chip ID: %d\n", 370 ret); 371 goto error_reg; 372 } 373 374 if (chipid != AW2013_RSTR_CHIP_ID) { 375 dev_err(&client->dev, "Chip reported wrong ID: %x\n", 376 chipid); 377 ret = -ENODEV; 378 goto error_reg; 379 } 380 381 ret = aw2013_probe_dt(chip); 382 if (ret < 0) 383 goto error_reg; 384 385 ret = regulator_disable(chip->vcc_regulator); 386 if (ret) { 387 dev_err(&client->dev, 388 "Failed to disable regulator: %d\n", ret); 389 goto error; 390 } 391 392 mutex_unlock(&chip->mutex); 393 394 return 0; 395 396 error_reg: 397 regulator_disable(chip->vcc_regulator); 398 399 error: 400 mutex_destroy(&chip->mutex); 401 return ret; 402 } 403 404 static void aw2013_remove(struct i2c_client *client) 405 { 406 struct aw2013 *chip = i2c_get_clientdata(client); 407 408 aw2013_chip_disable(chip); 409 410 mutex_destroy(&chip->mutex); 411 } 412 413 static const struct of_device_id aw2013_match_table[] = { 414 { .compatible = "awinic,aw2013", }, 415 { /* sentinel */ }, 416 }; 417 418 MODULE_DEVICE_TABLE(of, aw2013_match_table); 419 420 static struct i2c_driver aw2013_driver = { 421 .driver = { 422 .name = "leds-aw2013", 423 .of_match_table = of_match_ptr(aw2013_match_table), 424 }, 425 .probe = aw2013_probe, 426 .remove = aw2013_remove, 427 }; 428 429 module_i2c_driver(aw2013_driver); 430 431 MODULE_AUTHOR("Nikita Travkin <nikitos.tr@gmail.com>"); 432 MODULE_DESCRIPTION("AW2013 LED driver"); 433 MODULE_LICENSE("GPL v2"); 434