1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * TI LP8501 9 channel LED Driver 4 * 5 * Copyright (C) 2013 Texas Instruments 6 * 7 * Author: Milo(Woogyom) Kim <milo.kim@ti.com> 8 */ 9 10 #include <linux/delay.h> 11 #include <linux/firmware.h> 12 #include <linux/i2c.h> 13 #include <linux/init.h> 14 #include <linux/leds.h> 15 #include <linux/module.h> 16 #include <linux/mutex.h> 17 #include <linux/of.h> 18 #include <linux/platform_data/leds-lp55xx.h> 19 #include <linux/slab.h> 20 21 #include "leds-lp55xx-common.h" 22 23 #define LP8501_PROGRAM_LENGTH 32 24 #define LP8501_MAX_LEDS 9 25 26 /* Registers */ 27 #define LP8501_REG_ENABLE 0x00 28 #define LP8501_ENABLE BIT(6) 29 #define LP8501_EXEC_M 0x3F 30 #define LP8501_EXEC_ENG1_M 0x30 31 #define LP8501_EXEC_ENG2_M 0x0C 32 #define LP8501_EXEC_ENG3_M 0x03 33 #define LP8501_RUN_ENG1 0x20 34 #define LP8501_RUN_ENG2 0x08 35 #define LP8501_RUN_ENG3 0x02 36 37 #define LP8501_REG_OP_MODE 0x01 38 #define LP8501_MODE_ENG1_M 0x30 39 #define LP8501_MODE_ENG2_M 0x0C 40 #define LP8501_MODE_ENG3_M 0x03 41 #define LP8501_LOAD_ENG1 0x10 42 #define LP8501_LOAD_ENG2 0x04 43 #define LP8501_LOAD_ENG3 0x01 44 45 #define LP8501_REG_PWR_CONFIG 0x05 46 #define LP8501_PWR_CONFIG_M 0x03 47 48 #define LP8501_REG_LED_PWM_BASE 0x16 49 50 #define LP8501_REG_LED_CURRENT_BASE 0x26 51 52 #define LP8501_REG_CONFIG 0x36 53 #define LP8501_PWM_PSAVE BIT(7) 54 #define LP8501_AUTO_INC BIT(6) 55 #define LP8501_PWR_SAVE BIT(5) 56 #define LP8501_CP_MODE_MASK 0x18 57 #define LP8501_CP_MODE_SHIFT 3 58 #define LP8501_INT_CLK BIT(0) 59 #define LP8501_DEFAULT_CFG (LP8501_PWM_PSAVE | LP8501_AUTO_INC | LP8501_PWR_SAVE) 60 61 #define LP8501_REG_RESET 0x3D 62 #define LP8501_RESET 0xFF 63 64 #define LP8501_REG_PROG_PAGE_SEL 0x4F 65 #define LP8501_PAGE_ENG1 0 66 #define LP8501_PAGE_ENG2 1 67 #define LP8501_PAGE_ENG3 2 68 69 #define LP8501_REG_PROG_MEM 0x50 70 71 #define LP8501_ENG1_IS_LOADING(mode) \ 72 ((mode & LP8501_MODE_ENG1_M) == LP8501_LOAD_ENG1) 73 #define LP8501_ENG2_IS_LOADING(mode) \ 74 ((mode & LP8501_MODE_ENG2_M) == LP8501_LOAD_ENG2) 75 #define LP8501_ENG3_IS_LOADING(mode) \ 76 ((mode & LP8501_MODE_ENG3_M) == LP8501_LOAD_ENG3) 77 78 static inline void lp8501_wait_opmode_done(void) 79 { 80 usleep_range(1000, 2000); 81 } 82 83 static void lp8501_set_led_current(struct lp55xx_led *led, u8 led_current) 84 { 85 led->led_current = led_current; 86 lp55xx_write(led->chip, LP8501_REG_LED_CURRENT_BASE + led->chan_nr, 87 led_current); 88 } 89 90 static int lp8501_post_init_device(struct lp55xx_chip *chip) 91 { 92 int ret; 93 u8 val = LP8501_DEFAULT_CFG; 94 95 ret = lp55xx_write(chip, LP8501_REG_ENABLE, LP8501_ENABLE); 96 if (ret) 97 return ret; 98 99 /* Chip startup time is 500 us, 1 - 2 ms gives some margin */ 100 usleep_range(1000, 2000); 101 102 if (chip->pdata->clock_mode != LP55XX_CLOCK_EXT) 103 val |= LP8501_INT_CLK; 104 105 val |= (chip->pdata->charge_pump_mode << LP8501_CP_MODE_SHIFT) & LP8501_CP_MODE_MASK; 106 107 ret = lp55xx_write(chip, LP8501_REG_CONFIG, val); 108 if (ret) 109 return ret; 110 111 /* Power selection for each output */ 112 return lp55xx_update_bits(chip, LP8501_REG_PWR_CONFIG, 113 LP8501_PWR_CONFIG_M, chip->pdata->pwr_sel); 114 } 115 116 static void lp8501_load_engine(struct lp55xx_chip *chip) 117 { 118 enum lp55xx_engine_index idx = chip->engine_idx; 119 static const u8 mask[] = { 120 [LP55XX_ENGINE_1] = LP8501_MODE_ENG1_M, 121 [LP55XX_ENGINE_2] = LP8501_MODE_ENG2_M, 122 [LP55XX_ENGINE_3] = LP8501_MODE_ENG3_M, 123 }; 124 125 static const u8 val[] = { 126 [LP55XX_ENGINE_1] = LP8501_LOAD_ENG1, 127 [LP55XX_ENGINE_2] = LP8501_LOAD_ENG2, 128 [LP55XX_ENGINE_3] = LP8501_LOAD_ENG3, 129 }; 130 131 static const u8 page_sel[] = { 132 [LP55XX_ENGINE_1] = LP8501_PAGE_ENG1, 133 [LP55XX_ENGINE_2] = LP8501_PAGE_ENG2, 134 [LP55XX_ENGINE_3] = LP8501_PAGE_ENG3, 135 }; 136 137 lp55xx_update_bits(chip, LP8501_REG_OP_MODE, mask[idx], val[idx]); 138 139 lp8501_wait_opmode_done(); 140 141 lp55xx_write(chip, LP8501_REG_PROG_PAGE_SEL, page_sel[idx]); 142 } 143 144 static void lp8501_stop_engine(struct lp55xx_chip *chip) 145 { 146 lp55xx_write(chip, LP8501_REG_OP_MODE, 0); 147 lp8501_wait_opmode_done(); 148 } 149 150 static void lp8501_turn_off_channels(struct lp55xx_chip *chip) 151 { 152 int i; 153 154 for (i = 0; i < LP8501_MAX_LEDS; i++) 155 lp55xx_write(chip, LP8501_REG_LED_PWM_BASE + i, 0); 156 } 157 158 static void lp8501_run_engine(struct lp55xx_chip *chip, bool start) 159 { 160 int ret; 161 u8 mode; 162 u8 exec; 163 164 /* stop engine */ 165 if (!start) { 166 lp8501_stop_engine(chip); 167 lp8501_turn_off_channels(chip); 168 return; 169 } 170 171 /* 172 * To run the engine, 173 * operation mode and enable register should updated at the same time 174 */ 175 176 ret = lp55xx_read(chip, LP8501_REG_OP_MODE, &mode); 177 if (ret) 178 return; 179 180 ret = lp55xx_read(chip, LP8501_REG_ENABLE, &exec); 181 if (ret) 182 return; 183 184 /* change operation mode to RUN only when each engine is loading */ 185 if (LP8501_ENG1_IS_LOADING(mode)) { 186 mode = (mode & ~LP8501_MODE_ENG1_M) | LP8501_RUN_ENG1; 187 exec = (exec & ~LP8501_EXEC_ENG1_M) | LP8501_RUN_ENG1; 188 } 189 190 if (LP8501_ENG2_IS_LOADING(mode)) { 191 mode = (mode & ~LP8501_MODE_ENG2_M) | LP8501_RUN_ENG2; 192 exec = (exec & ~LP8501_EXEC_ENG2_M) | LP8501_RUN_ENG2; 193 } 194 195 if (LP8501_ENG3_IS_LOADING(mode)) { 196 mode = (mode & ~LP8501_MODE_ENG3_M) | LP8501_RUN_ENG3; 197 exec = (exec & ~LP8501_EXEC_ENG3_M) | LP8501_RUN_ENG3; 198 } 199 200 lp55xx_write(chip, LP8501_REG_OP_MODE, mode); 201 lp8501_wait_opmode_done(); 202 203 lp55xx_update_bits(chip, LP8501_REG_ENABLE, LP8501_EXEC_M, exec); 204 } 205 206 static int lp8501_update_program_memory(struct lp55xx_chip *chip, 207 const u8 *data, size_t size) 208 { 209 u8 pattern[LP8501_PROGRAM_LENGTH] = {0}; 210 unsigned cmd; 211 char c[3]; 212 int update_size; 213 int nrchars; 214 int offset = 0; 215 int ret; 216 int i; 217 218 /* clear program memory before updating */ 219 for (i = 0; i < LP8501_PROGRAM_LENGTH; i++) 220 lp55xx_write(chip, LP8501_REG_PROG_MEM + i, 0); 221 222 i = 0; 223 while ((offset < size - 1) && (i < LP8501_PROGRAM_LENGTH)) { 224 /* separate sscanfs because length is working only for %s */ 225 ret = sscanf(data + offset, "%2s%n ", c, &nrchars); 226 if (ret != 1) 227 goto err; 228 229 ret = sscanf(c, "%2x", &cmd); 230 if (ret != 1) 231 goto err; 232 233 pattern[i] = (u8)cmd; 234 offset += nrchars; 235 i++; 236 } 237 238 /* Each instruction is 16bit long. Check that length is even */ 239 if (i % 2) 240 goto err; 241 242 update_size = i; 243 for (i = 0; i < update_size; i++) 244 lp55xx_write(chip, LP8501_REG_PROG_MEM + i, pattern[i]); 245 246 return 0; 247 248 err: 249 dev_err(&chip->cl->dev, "wrong pattern format\n"); 250 return -EINVAL; 251 } 252 253 static void lp8501_firmware_loaded(struct lp55xx_chip *chip) 254 { 255 const struct firmware *fw = chip->fw; 256 257 if (fw->size > LP8501_PROGRAM_LENGTH) { 258 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n", 259 fw->size); 260 return; 261 } 262 263 /* 264 * Program memory sequence 265 * 1) set engine mode to "LOAD" 266 * 2) write firmware data into program memory 267 */ 268 269 lp8501_load_engine(chip); 270 lp8501_update_program_memory(chip, fw->data, fw->size); 271 } 272 273 static int lp8501_led_brightness(struct lp55xx_led *led) 274 { 275 struct lp55xx_chip *chip = led->chip; 276 int ret; 277 278 mutex_lock(&chip->lock); 279 ret = lp55xx_write(chip, LP8501_REG_LED_PWM_BASE + led->chan_nr, 280 led->brightness); 281 mutex_unlock(&chip->lock); 282 283 return ret; 284 } 285 286 /* Chip specific configurations */ 287 static struct lp55xx_device_config lp8501_cfg = { 288 .reset = { 289 .addr = LP8501_REG_RESET, 290 .val = LP8501_RESET, 291 }, 292 .enable = { 293 .addr = LP8501_REG_ENABLE, 294 .val = LP8501_ENABLE, 295 }, 296 .max_channel = LP8501_MAX_LEDS, 297 .post_init_device = lp8501_post_init_device, 298 .brightness_fn = lp8501_led_brightness, 299 .set_led_current = lp8501_set_led_current, 300 .firmware_cb = lp8501_firmware_loaded, 301 .run_engine = lp8501_run_engine, 302 }; 303 304 static int lp8501_probe(struct i2c_client *client) 305 { 306 const struct i2c_device_id *id = i2c_client_get_device_id(client); 307 int ret; 308 struct lp55xx_chip *chip; 309 struct lp55xx_led *led; 310 struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev); 311 struct device_node *np = dev_of_node(&client->dev); 312 313 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); 314 if (!chip) 315 return -ENOMEM; 316 317 chip->cfg = &lp8501_cfg; 318 319 if (!pdata) { 320 if (np) { 321 pdata = lp55xx_of_populate_pdata(&client->dev, np, 322 chip); 323 if (IS_ERR(pdata)) 324 return PTR_ERR(pdata); 325 } else { 326 dev_err(&client->dev, "no platform data\n"); 327 return -EINVAL; 328 } 329 } 330 331 led = devm_kcalloc(&client->dev, 332 pdata->num_channels, sizeof(*led), GFP_KERNEL); 333 if (!led) 334 return -ENOMEM; 335 336 chip->cl = client; 337 chip->pdata = pdata; 338 339 mutex_init(&chip->lock); 340 341 i2c_set_clientdata(client, led); 342 343 ret = lp55xx_init_device(chip); 344 if (ret) 345 goto err_init; 346 347 dev_info(&client->dev, "%s Programmable led chip found\n", id->name); 348 349 ret = lp55xx_register_leds(led, chip); 350 if (ret) 351 goto err_out; 352 353 ret = lp55xx_register_sysfs(chip); 354 if (ret) { 355 dev_err(&client->dev, "registering sysfs failed\n"); 356 goto err_out; 357 } 358 359 return 0; 360 361 err_out: 362 lp55xx_deinit_device(chip); 363 err_init: 364 return ret; 365 } 366 367 static void lp8501_remove(struct i2c_client *client) 368 { 369 struct lp55xx_led *led = i2c_get_clientdata(client); 370 struct lp55xx_chip *chip = led->chip; 371 372 lp8501_stop_engine(chip); 373 lp55xx_unregister_sysfs(chip); 374 lp55xx_deinit_device(chip); 375 } 376 377 static const struct i2c_device_id lp8501_id[] = { 378 { "lp8501", 0 }, 379 { } 380 }; 381 MODULE_DEVICE_TABLE(i2c, lp8501_id); 382 383 static const struct of_device_id of_lp8501_leds_match[] = { 384 { .compatible = "ti,lp8501", }, 385 {}, 386 }; 387 388 MODULE_DEVICE_TABLE(of, of_lp8501_leds_match); 389 390 static struct i2c_driver lp8501_driver = { 391 .driver = { 392 .name = "lp8501", 393 .of_match_table = of_lp8501_leds_match, 394 }, 395 .probe = lp8501_probe, 396 .remove = lp8501_remove, 397 .id_table = lp8501_id, 398 }; 399 400 module_i2c_driver(lp8501_driver); 401 402 MODULE_DESCRIPTION("Texas Instruments LP8501 LED driver"); 403 MODULE_AUTHOR("Milo Kim"); 404 MODULE_LICENSE("GPL"); 405