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_AUTO 0x18 57 #define LP8501_INT_CLK BIT(0) 58 #define LP8501_DEFAULT_CFG \ 59 (LP8501_PWM_PSAVE | LP8501_AUTO_INC | LP8501_PWR_SAVE | LP8501_CP_AUTO) 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 ret = lp55xx_write(chip, LP8501_REG_CONFIG, val); 106 if (ret) 107 return ret; 108 109 /* Power selection for each output */ 110 return lp55xx_update_bits(chip, LP8501_REG_PWR_CONFIG, 111 LP8501_PWR_CONFIG_M, chip->pdata->pwr_sel); 112 } 113 114 static void lp8501_load_engine(struct lp55xx_chip *chip) 115 { 116 enum lp55xx_engine_index idx = chip->engine_idx; 117 static const u8 mask[] = { 118 [LP55XX_ENGINE_1] = LP8501_MODE_ENG1_M, 119 [LP55XX_ENGINE_2] = LP8501_MODE_ENG2_M, 120 [LP55XX_ENGINE_3] = LP8501_MODE_ENG3_M, 121 }; 122 123 static const u8 val[] = { 124 [LP55XX_ENGINE_1] = LP8501_LOAD_ENG1, 125 [LP55XX_ENGINE_2] = LP8501_LOAD_ENG2, 126 [LP55XX_ENGINE_3] = LP8501_LOAD_ENG3, 127 }; 128 129 static const u8 page_sel[] = { 130 [LP55XX_ENGINE_1] = LP8501_PAGE_ENG1, 131 [LP55XX_ENGINE_2] = LP8501_PAGE_ENG2, 132 [LP55XX_ENGINE_3] = LP8501_PAGE_ENG3, 133 }; 134 135 lp55xx_update_bits(chip, LP8501_REG_OP_MODE, mask[idx], val[idx]); 136 137 lp8501_wait_opmode_done(); 138 139 lp55xx_write(chip, LP8501_REG_PROG_PAGE_SEL, page_sel[idx]); 140 } 141 142 static void lp8501_stop_engine(struct lp55xx_chip *chip) 143 { 144 lp55xx_write(chip, LP8501_REG_OP_MODE, 0); 145 lp8501_wait_opmode_done(); 146 } 147 148 static void lp8501_turn_off_channels(struct lp55xx_chip *chip) 149 { 150 int i; 151 152 for (i = 0; i < LP8501_MAX_LEDS; i++) 153 lp55xx_write(chip, LP8501_REG_LED_PWM_BASE + i, 0); 154 } 155 156 static void lp8501_run_engine(struct lp55xx_chip *chip, bool start) 157 { 158 int ret; 159 u8 mode; 160 u8 exec; 161 162 /* stop engine */ 163 if (!start) { 164 lp8501_stop_engine(chip); 165 lp8501_turn_off_channels(chip); 166 return; 167 } 168 169 /* 170 * To run the engine, 171 * operation mode and enable register should updated at the same time 172 */ 173 174 ret = lp55xx_read(chip, LP8501_REG_OP_MODE, &mode); 175 if (ret) 176 return; 177 178 ret = lp55xx_read(chip, LP8501_REG_ENABLE, &exec); 179 if (ret) 180 return; 181 182 /* change operation mode to RUN only when each engine is loading */ 183 if (LP8501_ENG1_IS_LOADING(mode)) { 184 mode = (mode & ~LP8501_MODE_ENG1_M) | LP8501_RUN_ENG1; 185 exec = (exec & ~LP8501_EXEC_ENG1_M) | LP8501_RUN_ENG1; 186 } 187 188 if (LP8501_ENG2_IS_LOADING(mode)) { 189 mode = (mode & ~LP8501_MODE_ENG2_M) | LP8501_RUN_ENG2; 190 exec = (exec & ~LP8501_EXEC_ENG2_M) | LP8501_RUN_ENG2; 191 } 192 193 if (LP8501_ENG3_IS_LOADING(mode)) { 194 mode = (mode & ~LP8501_MODE_ENG3_M) | LP8501_RUN_ENG3; 195 exec = (exec & ~LP8501_EXEC_ENG3_M) | LP8501_RUN_ENG3; 196 } 197 198 lp55xx_write(chip, LP8501_REG_OP_MODE, mode); 199 lp8501_wait_opmode_done(); 200 201 lp55xx_update_bits(chip, LP8501_REG_ENABLE, LP8501_EXEC_M, exec); 202 } 203 204 static int lp8501_update_program_memory(struct lp55xx_chip *chip, 205 const u8 *data, size_t size) 206 { 207 u8 pattern[LP8501_PROGRAM_LENGTH] = {0}; 208 unsigned cmd; 209 char c[3]; 210 int update_size; 211 int nrchars; 212 int offset = 0; 213 int ret; 214 int i; 215 216 /* clear program memory before updating */ 217 for (i = 0; i < LP8501_PROGRAM_LENGTH; i++) 218 lp55xx_write(chip, LP8501_REG_PROG_MEM + i, 0); 219 220 i = 0; 221 while ((offset < size - 1) && (i < LP8501_PROGRAM_LENGTH)) { 222 /* separate sscanfs because length is working only for %s */ 223 ret = sscanf(data + offset, "%2s%n ", c, &nrchars); 224 if (ret != 1) 225 goto err; 226 227 ret = sscanf(c, "%2x", &cmd); 228 if (ret != 1) 229 goto err; 230 231 pattern[i] = (u8)cmd; 232 offset += nrchars; 233 i++; 234 } 235 236 /* Each instruction is 16bit long. Check that length is even */ 237 if (i % 2) 238 goto err; 239 240 update_size = i; 241 for (i = 0; i < update_size; i++) 242 lp55xx_write(chip, LP8501_REG_PROG_MEM + i, pattern[i]); 243 244 return 0; 245 246 err: 247 dev_err(&chip->cl->dev, "wrong pattern format\n"); 248 return -EINVAL; 249 } 250 251 static void lp8501_firmware_loaded(struct lp55xx_chip *chip) 252 { 253 const struct firmware *fw = chip->fw; 254 255 if (fw->size > LP8501_PROGRAM_LENGTH) { 256 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n", 257 fw->size); 258 return; 259 } 260 261 /* 262 * Program memory sequence 263 * 1) set engine mode to "LOAD" 264 * 2) write firmware data into program memory 265 */ 266 267 lp8501_load_engine(chip); 268 lp8501_update_program_memory(chip, fw->data, fw->size); 269 } 270 271 static int lp8501_led_brightness(struct lp55xx_led *led) 272 { 273 struct lp55xx_chip *chip = led->chip; 274 int ret; 275 276 mutex_lock(&chip->lock); 277 ret = lp55xx_write(chip, LP8501_REG_LED_PWM_BASE + led->chan_nr, 278 led->brightness); 279 mutex_unlock(&chip->lock); 280 281 return ret; 282 } 283 284 /* Chip specific configurations */ 285 static struct lp55xx_device_config lp8501_cfg = { 286 .reset = { 287 .addr = LP8501_REG_RESET, 288 .val = LP8501_RESET, 289 }, 290 .enable = { 291 .addr = LP8501_REG_ENABLE, 292 .val = LP8501_ENABLE, 293 }, 294 .max_channel = LP8501_MAX_LEDS, 295 .post_init_device = lp8501_post_init_device, 296 .brightness_fn = lp8501_led_brightness, 297 .set_led_current = lp8501_set_led_current, 298 .firmware_cb = lp8501_firmware_loaded, 299 .run_engine = lp8501_run_engine, 300 }; 301 302 static int lp8501_probe(struct i2c_client *client, 303 const struct i2c_device_id *id) 304 { 305 int ret; 306 struct lp55xx_chip *chip; 307 struct lp55xx_led *led; 308 struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev); 309 struct device_node *np = dev_of_node(&client->dev); 310 311 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); 312 if (!chip) 313 return -ENOMEM; 314 315 chip->cfg = &lp8501_cfg; 316 317 if (!pdata) { 318 if (np) { 319 pdata = lp55xx_of_populate_pdata(&client->dev, np, 320 chip); 321 if (IS_ERR(pdata)) 322 return PTR_ERR(pdata); 323 } else { 324 dev_err(&client->dev, "no platform data\n"); 325 return -EINVAL; 326 } 327 } 328 329 led = devm_kcalloc(&client->dev, 330 pdata->num_channels, sizeof(*led), GFP_KERNEL); 331 if (!led) 332 return -ENOMEM; 333 334 chip->cl = client; 335 chip->pdata = pdata; 336 337 mutex_init(&chip->lock); 338 339 i2c_set_clientdata(client, led); 340 341 ret = lp55xx_init_device(chip); 342 if (ret) 343 goto err_init; 344 345 dev_info(&client->dev, "%s Programmable led chip found\n", id->name); 346 347 ret = lp55xx_register_leds(led, chip); 348 if (ret) 349 goto err_out; 350 351 ret = lp55xx_register_sysfs(chip); 352 if (ret) { 353 dev_err(&client->dev, "registering sysfs failed\n"); 354 goto err_out; 355 } 356 357 return 0; 358 359 err_out: 360 lp55xx_deinit_device(chip); 361 err_init: 362 return ret; 363 } 364 365 static void lp8501_remove(struct i2c_client *client) 366 { 367 struct lp55xx_led *led = i2c_get_clientdata(client); 368 struct lp55xx_chip *chip = led->chip; 369 370 lp8501_stop_engine(chip); 371 lp55xx_unregister_sysfs(chip); 372 lp55xx_deinit_device(chip); 373 } 374 375 static const struct i2c_device_id lp8501_id[] = { 376 { "lp8501", 0 }, 377 { } 378 }; 379 MODULE_DEVICE_TABLE(i2c, lp8501_id); 380 381 #ifdef CONFIG_OF 382 static const struct of_device_id of_lp8501_leds_match[] = { 383 { .compatible = "ti,lp8501", }, 384 {}, 385 }; 386 387 MODULE_DEVICE_TABLE(of, of_lp8501_leds_match); 388 #endif 389 390 static struct i2c_driver lp8501_driver = { 391 .driver = { 392 .name = "lp8501", 393 .of_match_table = of_match_ptr(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