1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * TI LP8860 4-Channel LED Driver 4 * 5 * Copyright (C) 2014 Texas Instruments 6 * 7 * Author: Dan Murphy <dmurphy@ti.com> 8 */ 9 10 #include <linux/i2c.h> 11 #include <linux/init.h> 12 #include <linux/leds.h> 13 #include <linux/regmap.h> 14 #include <linux/regulator/consumer.h> 15 #include <linux/module.h> 16 #include <linux/mutex.h> 17 #include <linux/of.h> 18 #include <linux/gpio/consumer.h> 19 #include <linux/slab.h> 20 21 #define LP8860_DISP_CL1_BRT_MSB 0x00 22 #define LP8860_DISP_CL1_BRT_LSB 0x01 23 #define LP8860_DISP_CL1_CURR_MSB 0x02 24 #define LP8860_DISP_CL1_CURR_LSB 0x03 25 #define LP8860_CL2_BRT_MSB 0x04 26 #define LP8860_CL2_BRT_LSB 0x05 27 #define LP8860_CL2_CURRENT 0x06 28 #define LP8860_CL3_BRT_MSB 0x07 29 #define LP8860_CL3_BRT_LSB 0x08 30 #define LP8860_CL3_CURRENT 0x09 31 #define LP8860_CL4_BRT_MSB 0x0a 32 #define LP8860_CL4_BRT_LSB 0x0b 33 #define LP8860_CL4_CURRENT 0x0c 34 #define LP8860_CONFIG 0x0d 35 #define LP8860_STATUS 0x0e 36 #define LP8860_FAULT 0x0f 37 #define LP8860_LED_FAULT 0x10 38 #define LP8860_FAULT_CLEAR 0x11 39 #define LP8860_ID 0x12 40 #define LP8860_TEMP_MSB 0x13 41 #define LP8860_TEMP_LSB 0x14 42 #define LP8860_DISP_LED_CURR_MSB 0x15 43 #define LP8860_DISP_LED_CURR_LSB 0x16 44 #define LP8860_DISP_LED_PWM_MSB 0x17 45 #define LP8860_DISP_LED_PWM_LSB 0x18 46 #define LP8860_EEPROM_CNTRL 0x19 47 #define LP8860_EEPROM_UNLOCK 0x1a 48 49 #define LP8860_EEPROM_REG_0 0x60 50 #define LP8860_EEPROM_REG_1 0x61 51 #define LP8860_EEPROM_REG_2 0x62 52 #define LP8860_EEPROM_REG_3 0x63 53 #define LP8860_EEPROM_REG_4 0x64 54 #define LP8860_EEPROM_REG_5 0x65 55 #define LP8860_EEPROM_REG_6 0x66 56 #define LP8860_EEPROM_REG_7 0x67 57 #define LP8860_EEPROM_REG_8 0x68 58 #define LP8860_EEPROM_REG_9 0x69 59 #define LP8860_EEPROM_REG_10 0x6a 60 #define LP8860_EEPROM_REG_11 0x6b 61 #define LP8860_EEPROM_REG_12 0x6c 62 #define LP8860_EEPROM_REG_13 0x6d 63 #define LP8860_EEPROM_REG_14 0x6e 64 #define LP8860_EEPROM_REG_15 0x6f 65 #define LP8860_EEPROM_REG_16 0x70 66 #define LP8860_EEPROM_REG_17 0x71 67 #define LP8860_EEPROM_REG_18 0x72 68 #define LP8860_EEPROM_REG_19 0x73 69 #define LP8860_EEPROM_REG_20 0x74 70 #define LP8860_EEPROM_REG_21 0x75 71 #define LP8860_EEPROM_REG_22 0x76 72 #define LP8860_EEPROM_REG_23 0x77 73 #define LP8860_EEPROM_REG_24 0x78 74 75 #define LP8860_LOCK_EEPROM 0x00 76 #define LP8860_UNLOCK_EEPROM 0x01 77 #define LP8860_PROGRAM_EEPROM 0x02 78 #define LP8860_EEPROM_CODE_1 0x08 79 #define LP8860_EEPROM_CODE_2 0xba 80 #define LP8860_EEPROM_CODE_3 0xef 81 82 #define LP8860_CLEAR_FAULTS 0x01 83 84 #define LP8860_NAME "lp8860" 85 86 /** 87 * struct lp8860_led 88 * @lock: Lock for reading/writing the device 89 * @client: Pointer to the I2C client 90 * @led_dev: led class device pointer 91 * @regmap: Devices register map 92 */ 93 struct lp8860_led { 94 struct mutex lock; 95 struct i2c_client *client; 96 struct led_classdev led_dev; 97 struct regmap *regmap; 98 }; 99 100 static bool program_eeprom; 101 module_param(program_eeprom, bool, 0644); 102 MODULE_PARM_DESC(program_eeprom, "Program the configuration EEPROM on device startup"); 103 104 /* 105 * EEPROM bits are intended to be set/programmed before normal operation only 106 * once during silicon production, but can be reprogrammed for evaluation purposes 107 * up to 1000 cycles. To program this EEPROM using this driver, update the below 108 * table and set the module param "program_eeprom" to 1 109 */ 110 static const struct reg_sequence lp8860_eeprom_disp_regs[] = { 111 { LP8860_EEPROM_REG_0, 0xed }, 112 { LP8860_EEPROM_REG_1, 0xdf }, 113 { LP8860_EEPROM_REG_2, 0xdc }, 114 { LP8860_EEPROM_REG_3, 0xf0 }, 115 { LP8860_EEPROM_REG_4, 0xdf }, 116 { LP8860_EEPROM_REG_5, 0xe5 }, 117 { LP8860_EEPROM_REG_6, 0xf2 }, 118 { LP8860_EEPROM_REG_7, 0x77 }, 119 { LP8860_EEPROM_REG_8, 0x77 }, 120 { LP8860_EEPROM_REG_9, 0x71 }, 121 { LP8860_EEPROM_REG_10, 0x3f }, 122 { LP8860_EEPROM_REG_11, 0xb7 }, 123 { LP8860_EEPROM_REG_12, 0x17 }, 124 { LP8860_EEPROM_REG_13, 0xef }, 125 { LP8860_EEPROM_REG_14, 0xb0 }, 126 { LP8860_EEPROM_REG_15, 0x87 }, 127 { LP8860_EEPROM_REG_16, 0xce }, 128 { LP8860_EEPROM_REG_17, 0x72 }, 129 { LP8860_EEPROM_REG_18, 0xe5 }, 130 { LP8860_EEPROM_REG_19, 0xdf }, 131 { LP8860_EEPROM_REG_20, 0x35 }, 132 { LP8860_EEPROM_REG_21, 0x06 }, 133 { LP8860_EEPROM_REG_22, 0xdc }, 134 { LP8860_EEPROM_REG_23, 0x88 }, 135 { LP8860_EEPROM_REG_24, 0x3E }, 136 }; 137 138 static int lp8860_fault_check(struct lp8860_led *led) 139 { 140 int ret, fault; 141 unsigned int read_buf; 142 143 ret = regmap_read(led->regmap, LP8860_LED_FAULT, &read_buf); 144 if (ret) 145 goto out; 146 147 fault = read_buf; 148 149 ret = regmap_read(led->regmap, LP8860_FAULT, &read_buf); 150 if (ret) 151 goto out; 152 153 fault |= read_buf; 154 155 /* Attempt to clear any faults */ 156 if (fault) 157 ret = regmap_write(led->regmap, LP8860_FAULT_CLEAR, 158 LP8860_CLEAR_FAULTS); 159 out: 160 return ret; 161 } 162 163 static int lp8860_brightness_set(struct led_classdev *led_cdev, 164 enum led_brightness brt_val) 165 { 166 struct lp8860_led *led = 167 container_of(led_cdev, struct lp8860_led, led_dev); 168 int disp_brightness = brt_val * 255; 169 int ret; 170 171 guard(mutex)(&led->lock); 172 173 ret = lp8860_fault_check(led); 174 if (ret) { 175 dev_err(&led->client->dev, "Cannot read/clear faults\n"); 176 return ret; 177 } 178 179 ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_MSB, 180 (disp_brightness & 0xff00) >> 8); 181 if (ret) { 182 dev_err(&led->client->dev, "Cannot write CL1 MSB\n"); 183 return ret; 184 } 185 186 ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_LSB, 187 disp_brightness & 0xff); 188 if (ret) { 189 dev_err(&led->client->dev, "Cannot write CL1 LSB\n"); 190 return ret; 191 } 192 193 return 0; 194 } 195 196 static int lp8860_program_eeprom(struct lp8860_led *led) 197 { 198 int ret, reg_count; 199 200 guard(mutex)(&led->lock); 201 202 ret = lp8860_fault_check(led); 203 if (ret) { 204 dev_err(&led->client->dev, "Cannot read/clear faults\n"); 205 return ret; 206 } 207 208 ret = regmap_write(led->regmap, LP8860_EEPROM_UNLOCK, LP8860_EEPROM_CODE_1); 209 if (ret) { 210 dev_err(&led->client->dev, "EEPROM Unlock failed\n"); 211 return ret; 212 } 213 214 ret = regmap_write(led->regmap, LP8860_EEPROM_UNLOCK, LP8860_EEPROM_CODE_2); 215 if (ret) { 216 dev_err(&led->client->dev, "EEPROM Unlock failed\n"); 217 return ret; 218 } 219 ret = regmap_write(led->regmap, LP8860_EEPROM_UNLOCK, LP8860_EEPROM_CODE_3); 220 if (ret) { 221 dev_err(&led->client->dev, "EEPROM Unlock failed\n"); 222 return ret; 223 } 224 225 reg_count = ARRAY_SIZE(lp8860_eeprom_disp_regs); 226 ret = regmap_multi_reg_write(led->regmap, lp8860_eeprom_disp_regs, reg_count); 227 if (ret) { 228 dev_err(&led->client->dev, "Failed writing EEPROM\n"); 229 return ret; 230 } 231 232 ret = regmap_write(led->regmap, LP8860_EEPROM_UNLOCK, LP8860_LOCK_EEPROM); 233 if (ret) 234 return ret; 235 236 ret = regmap_write(led->regmap, 237 LP8860_EEPROM_CNTRL, 238 LP8860_PROGRAM_EEPROM); 239 if (ret) { 240 dev_err(&led->client->dev, "Failed programming EEPROM\n"); 241 return ret; 242 } 243 244 return 0; 245 } 246 247 static const struct regmap_range lp8860_reg_ranges[] = { 248 regmap_reg_range(LP8860_DISP_CL1_BRT_MSB, LP8860_EEPROM_UNLOCK), 249 regmap_reg_range(LP8860_EEPROM_REG_0, LP8860_EEPROM_REG_24), 250 }; 251 252 static const struct regmap_access_table lp8860_reg_table = { 253 .yes_ranges = lp8860_reg_ranges, 254 .n_yes_ranges = ARRAY_SIZE(lp8860_reg_ranges), 255 }; 256 257 static const struct regmap_config lp8860_regmap_config = { 258 .reg_bits = 8, 259 .val_bits = 8, 260 .rd_table = &lp8860_reg_table, 261 .wr_table = &lp8860_reg_table, 262 .max_register = LP8860_EEPROM_REG_24, 263 }; 264 265 static void lp8860_disable_gpio(void *data) 266 { 267 struct gpio_desc *gpio = data; 268 269 gpiod_set_value(gpio, 0); 270 } 271 272 static int lp8860_probe(struct i2c_client *client) 273 { 274 int ret; 275 struct lp8860_led *led; 276 struct device_node *np = dev_of_node(&client->dev); 277 struct device_node *child_node; 278 struct led_init_data init_data = {}; 279 struct gpio_desc *enable_gpio; 280 281 led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL); 282 if (!led) 283 return -ENOMEM; 284 285 child_node = of_get_next_available_child(np, NULL); 286 if (!child_node) 287 return -EINVAL; 288 289 enable_gpio = devm_gpiod_get_optional(&client->dev, "enable", GPIOD_OUT_LOW); 290 if (IS_ERR(enable_gpio)) 291 return dev_err_probe(&client->dev, PTR_ERR(enable_gpio), 292 "Failed to get enable GPIO\n"); 293 devm_add_action_or_reset(&client->dev, lp8860_disable_gpio, enable_gpio); 294 295 ret = devm_regulator_get_enable_optional(&client->dev, "vled"); 296 if (ret && ret != -ENODEV) 297 return dev_err_probe(&client->dev, ret, 298 "Failed to enable vled regulator\n"); 299 300 led->client = client; 301 led->led_dev.brightness_set_blocking = lp8860_brightness_set; 302 303 ret = devm_mutex_init(&client->dev, &led->lock); 304 if (ret) 305 return dev_err_probe(&client->dev, ret, "Failed to initialize lock\n"); 306 307 led->regmap = devm_regmap_init_i2c(client, &lp8860_regmap_config); 308 if (IS_ERR(led->regmap)) { 309 ret = PTR_ERR(led->regmap); 310 dev_err(&client->dev, "Failed to allocate register map: %d\n", 311 ret); 312 return ret; 313 } 314 315 if (program_eeprom) { 316 ret = lp8860_program_eeprom(led); 317 if (ret) 318 return ret; 319 } 320 321 init_data.fwnode = of_fwnode_handle(child_node); 322 init_data.devicename = LP8860_NAME; 323 init_data.default_label = ":display_cluster"; 324 325 ret = devm_led_classdev_register_ext(&client->dev, &led->led_dev, 326 &init_data); 327 if (ret) { 328 dev_err(&client->dev, "led register err: %d\n", ret); 329 return ret; 330 } 331 332 return 0; 333 } 334 335 static const struct i2c_device_id lp8860_id[] = { 336 { "lp8860" }, 337 { } 338 }; 339 MODULE_DEVICE_TABLE(i2c, lp8860_id); 340 341 static const struct of_device_id of_lp8860_leds_match[] = { 342 { .compatible = "ti,lp8860", }, 343 {}, 344 }; 345 MODULE_DEVICE_TABLE(of, of_lp8860_leds_match); 346 347 static struct i2c_driver lp8860_driver = { 348 .driver = { 349 .name = "lp8860", 350 .of_match_table = of_lp8860_leds_match, 351 }, 352 .probe = lp8860_probe, 353 .id_table = lp8860_id, 354 }; 355 module_i2c_driver(lp8860_driver); 356 357 MODULE_DESCRIPTION("Texas Instruments LP8860 LED driver"); 358 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>"); 359 MODULE_LICENSE("GPL v2"); 360