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1// SPDX-License-Identifier: GPL-2.02// TI LM3692x LED chip family driver3// Copyright (C) 2017-18 Texas Instruments Incorporated - https://www.ti.com/4 5#include <linux/gpio/consumer.h>6#include <linux/i2c.h>7#include <linux/init.h>8#include <linux/leds.h>9#include <linux/log2.h>10#include <linux/mod_devicetable.h>11#include <linux/module.h>12#include <linux/mutex.h>13#include <linux/regmap.h>14#include <linux/regulator/consumer.h>15#include <linux/slab.h>16 17#define LM36922_MODEL 018#define LM36923_MODEL 119 20#define LM3692X_REV 0x021#define LM3692X_RESET 0x122#define LM3692X_EN 0x1023#define LM3692X_BRT_CTRL 0x1124#define LM3692X_PWM_CTRL 0x1225#define LM3692X_BOOST_CTRL 0x1326#define LM3692X_AUTO_FREQ_HI 0x1527#define LM3692X_AUTO_FREQ_LO 0x1628#define LM3692X_BL_ADJ_THRESH 0x1729#define LM3692X_BRT_LSB 0x1830#define LM3692X_BRT_MSB 0x1931#define LM3692X_FAULT_CTRL 0x1e32#define LM3692X_FAULT_FLAGS 0x1f33 34#define LM3692X_SW_RESET BIT(0)35#define LM3692X_DEVICE_EN BIT(0)36#define LM3692X_LED1_EN BIT(1)37#define LM3692X_LED2_EN BIT(2)38#define LM36923_LED3_EN BIT(3)39#define LM3692X_ENABLE_MASK (LM3692X_DEVICE_EN | LM3692X_LED1_EN | \40 LM3692X_LED2_EN | LM36923_LED3_EN)41 42/* Brightness Control Bits */43#define LM3692X_BL_ADJ_POL BIT(0)44#define LM3692X_RAMP_RATE_125us 0x0045#define LM3692X_RAMP_RATE_250us BIT(1)46#define LM3692X_RAMP_RATE_500us BIT(2)47#define LM3692X_RAMP_RATE_1ms (BIT(1) | BIT(2))48#define LM3692X_RAMP_RATE_2ms BIT(3)49#define LM3692X_RAMP_RATE_4ms (BIT(3) | BIT(1))50#define LM3692X_RAMP_RATE_8ms (BIT(2) | BIT(3))51#define LM3692X_RAMP_RATE_16ms (BIT(1) | BIT(2) | BIT(3))52#define LM3692X_RAMP_EN BIT(4)53#define LM3692X_BRHT_MODE_REG 0x0054#define LM3692X_BRHT_MODE_PWM BIT(5)55#define LM3692X_BRHT_MODE_MULTI_RAMP BIT(6)56#define LM3692X_BRHT_MODE_RAMP_MULTI (BIT(5) | BIT(6))57#define LM3692X_MAP_MODE_EXP BIT(7)58 59/* PWM Register Bits */60#define LM3692X_PWM_FILTER_100 BIT(0)61#define LM3692X_PWM_FILTER_150 BIT(1)62#define LM3692X_PWM_FILTER_200 (BIT(0) | BIT(1))63#define LM3692X_PWM_HYSTER_1LSB BIT(2)64#define LM3692X_PWM_HYSTER_2LSB BIT(3)65#define LM3692X_PWM_HYSTER_3LSB (BIT(3) | BIT(2))66#define LM3692X_PWM_HYSTER_4LSB BIT(4)67#define LM3692X_PWM_HYSTER_5LSB (BIT(4) | BIT(2))68#define LM3692X_PWM_HYSTER_6LSB (BIT(4) | BIT(3))69#define LM3692X_PWM_POLARITY BIT(5)70#define LM3692X_PWM_SAMP_4MHZ BIT(6)71#define LM3692X_PWM_SAMP_24MHZ BIT(7)72 73/* Boost Control Bits */74#define LM3692X_OCP_PROT_1A BIT(0)75#define LM3692X_OCP_PROT_1_25A BIT(1)76#define LM3692X_OCP_PROT_1_5A (BIT(0) | BIT(1))77#define LM3692X_OVP_21V BIT(2)78#define LM3692X_OVP_25V BIT(3)79#define LM3692X_OVP_29V (BIT(2) | BIT(3))80#define LM3692X_MIN_IND_22UH BIT(4)81#define LM3692X_BOOST_SW_1MHZ BIT(5)82#define LM3692X_BOOST_SW_NO_SHIFT BIT(6)83 84/* Fault Control Bits */85#define LM3692X_FAULT_CTRL_OVP BIT(0)86#define LM3692X_FAULT_CTRL_OCP BIT(1)87#define LM3692X_FAULT_CTRL_TSD BIT(2)88#define LM3692X_FAULT_CTRL_OPEN BIT(3)89 90/* Fault Flag Bits */91#define LM3692X_FAULT_FLAG_OVP BIT(0)92#define LM3692X_FAULT_FLAG_OCP BIT(1)93#define LM3692X_FAULT_FLAG_TSD BIT(2)94#define LM3692X_FAULT_FLAG_SHRT BIT(3)95#define LM3692X_FAULT_FLAG_OPEN BIT(4)96 97/**98 * struct lm3692x_led99 * @lock: Lock for reading/writing the device100 * @client: Pointer to the I2C client101 * @led_dev: LED class device pointer102 * @regmap: Devices register map103 * @enable_gpio: VDDIO/EN gpio to enable communication interface104 * @regulator: LED supply regulator pointer105 * @led_enable: LED sync to be enabled106 * @model_id: Current device model ID enumerated107 */108struct lm3692x_led {109 struct mutex lock;110 struct i2c_client *client;111 struct led_classdev led_dev;112 struct regmap *regmap;113 struct gpio_desc *enable_gpio;114 struct regulator *regulator;115 int led_enable;116 int model_id;117 118 u8 boost_ctrl, brightness_ctrl;119 bool enabled;120};121 122static const struct reg_default lm3692x_reg_defs[] = {123 {LM3692X_EN, 0xf},124 {LM3692X_BRT_CTRL, 0x61},125 {LM3692X_PWM_CTRL, 0x73},126 {LM3692X_BOOST_CTRL, 0x6f},127 {LM3692X_AUTO_FREQ_HI, 0x0},128 {LM3692X_AUTO_FREQ_LO, 0x0},129 {LM3692X_BL_ADJ_THRESH, 0x0},130 {LM3692X_BRT_LSB, 0x7},131 {LM3692X_BRT_MSB, 0xff},132 {LM3692X_FAULT_CTRL, 0x7},133};134 135static const struct regmap_config lm3692x_regmap_config = {136 .reg_bits = 8,137 .val_bits = 8,138 139 .max_register = LM3692X_FAULT_FLAGS,140 .reg_defaults = lm3692x_reg_defs,141 .num_reg_defaults = ARRAY_SIZE(lm3692x_reg_defs),142 .cache_type = REGCACHE_MAPLE,143};144 145static int lm3692x_fault_check(struct lm3692x_led *led)146{147 int ret;148 unsigned int read_buf;149 150 ret = regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);151 if (ret)152 return ret;153 154 if (read_buf)155 dev_err(&led->client->dev, "Detected a fault 0x%X\n", read_buf);156 157 /* The first read may clear the fault. Check again to see if the fault158 * still exits and return that value.159 */160 regmap_read(led->regmap, LM3692X_FAULT_FLAGS, &read_buf);161 if (read_buf)162 dev_err(&led->client->dev, "Second read of fault flags 0x%X\n",163 read_buf);164 165 return read_buf;166}167 168static int lm3692x_leds_enable(struct lm3692x_led *led)169{170 int enable_state;171 int ret, reg_ret;172 173 if (led->enabled)174 return 0;175 176 if (led->regulator) {177 ret = regulator_enable(led->regulator);178 if (ret) {179 dev_err(&led->client->dev,180 "Failed to enable regulator: %d\n", ret);181 return ret;182 }183 }184 185 if (led->enable_gpio)186 gpiod_direction_output(led->enable_gpio, 1);187 188 ret = lm3692x_fault_check(led);189 if (ret) {190 dev_err(&led->client->dev, "Cannot read/clear faults: %d\n",191 ret);192 goto out;193 }194 195 ret = regmap_write(led->regmap, LM3692X_BRT_CTRL, 0x00);196 if (ret)197 goto out;198 199 /*200 * For glitch free operation, the following data should201 * only be written while LEDx enable bits are 0 and the device enable202 * bit is set to 1.203 * per Section 7.5.14 of the data sheet204 */205 ret = regmap_write(led->regmap, LM3692X_EN, LM3692X_DEVICE_EN);206 if (ret)207 goto out;208 209 /* Set the brightness to 0 so when enabled the LEDs do not come210 * on with full brightness.211 */212 ret = regmap_write(led->regmap, LM3692X_BRT_MSB, 0);213 if (ret)214 goto out;215 216 ret = regmap_write(led->regmap, LM3692X_BRT_LSB, 0);217 if (ret)218 goto out;219 220 ret = regmap_write(led->regmap, LM3692X_PWM_CTRL,221 LM3692X_PWM_FILTER_100 | LM3692X_PWM_SAMP_24MHZ);222 if (ret)223 goto out;224 225 ret = regmap_write(led->regmap, LM3692X_BOOST_CTRL, led->boost_ctrl);226 if (ret)227 goto out;228 229 ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_HI, 0x00);230 if (ret)231 goto out;232 233 ret = regmap_write(led->regmap, LM3692X_AUTO_FREQ_LO, 0x00);234 if (ret)235 goto out;236 237 ret = regmap_write(led->regmap, LM3692X_BL_ADJ_THRESH, 0x00);238 if (ret)239 goto out;240 241 ret = regmap_write(led->regmap, LM3692X_BRT_CTRL,242 LM3692X_BL_ADJ_POL | LM3692X_RAMP_EN);243 if (ret)244 goto out;245 246 switch (led->led_enable) {247 case 0:248 default:249 if (led->model_id == LM36923_MODEL)250 enable_state = LM3692X_LED1_EN | LM3692X_LED2_EN |251 LM36923_LED3_EN;252 else253 enable_state = LM3692X_LED1_EN | LM3692X_LED2_EN;254 255 break;256 case 1:257 enable_state = LM3692X_LED1_EN;258 break;259 case 2:260 enable_state = LM3692X_LED2_EN;261 break;262 263 case 3:264 if (led->model_id == LM36923_MODEL) {265 enable_state = LM36923_LED3_EN;266 break;267 }268 269 ret = -EINVAL;270 dev_err(&led->client->dev,271 "LED3 sync not available on this device\n");272 goto out;273 }274 275 ret = regmap_update_bits(led->regmap, LM3692X_EN, LM3692X_ENABLE_MASK,276 enable_state | LM3692X_DEVICE_EN);277 278 led->enabled = true;279 return ret;280out:281 dev_err(&led->client->dev, "Fail writing initialization values\n");282 283 if (led->enable_gpio)284 gpiod_direction_output(led->enable_gpio, 0);285 286 if (led->regulator) {287 reg_ret = regulator_disable(led->regulator);288 if (reg_ret)289 dev_err(&led->client->dev,290 "Failed to disable regulator: %d\n", reg_ret);291 }292 293 return ret;294}295 296static int lm3692x_leds_disable(struct lm3692x_led *led)297{298 int ret;299 300 if (!led->enabled)301 return 0;302 303 ret = regmap_update_bits(led->regmap, LM3692X_EN, LM3692X_DEVICE_EN, 0);304 if (ret) {305 dev_err(&led->client->dev, "Failed to disable regulator: %d\n",306 ret);307 return ret;308 }309 310 if (led->enable_gpio)311 gpiod_direction_output(led->enable_gpio, 0);312 313 if (led->regulator) {314 ret = regulator_disable(led->regulator);315 if (ret)316 dev_err(&led->client->dev,317 "Failed to disable regulator: %d\n", ret);318 }319 320 led->enabled = false;321 return ret;322}323 324static int lm3692x_brightness_set(struct led_classdev *led_cdev,325 enum led_brightness brt_val)326{327 struct lm3692x_led *led =328 container_of(led_cdev, struct lm3692x_led, led_dev);329 int ret;330 int led_brightness_lsb = (brt_val >> 5);331 332 mutex_lock(&led->lock);333 334 if (brt_val == 0) {335 ret = lm3692x_leds_disable(led);336 goto out;337 } else {338 lm3692x_leds_enable(led);339 }340 341 ret = lm3692x_fault_check(led);342 if (ret) {343 dev_err(&led->client->dev, "Cannot read/clear faults: %d\n",344 ret);345 goto out;346 }347 348 ret = regmap_write(led->regmap, LM3692X_BRT_MSB, brt_val);349 if (ret) {350 dev_err(&led->client->dev, "Cannot write MSB: %d\n", ret);351 goto out;352 }353 354 ret = regmap_write(led->regmap, LM3692X_BRT_LSB, led_brightness_lsb);355 if (ret) {356 dev_err(&led->client->dev, "Cannot write LSB: %d\n", ret);357 goto out;358 }359out:360 mutex_unlock(&led->lock);361 return ret;362}363 364static enum led_brightness lm3692x_max_brightness(struct lm3692x_led *led,365 u32 max_cur)366{367 u32 max_code;368 369 /* see p.12 of LM36922 data sheet for brightness formula */370 max_code = ((max_cur * 1000) - 37806) / 12195;371 if (max_code > 0x7FF)372 max_code = 0x7FF;373 374 return max_code >> 3;375}376 377static int lm3692x_probe_dt(struct lm3692x_led *led)378{379 struct fwnode_handle *child = NULL;380 struct led_init_data init_data = {};381 u32 ovp, max_cur;382 int ret;383 384 led->enable_gpio = devm_gpiod_get_optional(&led->client->dev,385 "enable", GPIOD_OUT_LOW);386 if (IS_ERR(led->enable_gpio)) {387 ret = PTR_ERR(led->enable_gpio);388 dev_err(&led->client->dev, "Failed to get enable gpio: %d\n",389 ret);390 return ret;391 }392 393 led->regulator = devm_regulator_get_optional(&led->client->dev, "vled");394 if (IS_ERR(led->regulator)) {395 ret = PTR_ERR(led->regulator);396 if (ret != -ENODEV)397 return dev_err_probe(&led->client->dev, ret,398 "Failed to get vled regulator\n");399 400 led->regulator = NULL;401 }402 403 led->boost_ctrl = LM3692X_BOOST_SW_1MHZ |404 LM3692X_BOOST_SW_NO_SHIFT |405 LM3692X_OCP_PROT_1_5A;406 ret = device_property_read_u32(&led->client->dev,407 "ti,ovp-microvolt", &ovp);408 if (ret) {409 led->boost_ctrl |= LM3692X_OVP_29V;410 } else {411 switch (ovp) {412 case 17000000:413 break;414 case 21000000:415 led->boost_ctrl |= LM3692X_OVP_21V;416 break;417 case 25000000:418 led->boost_ctrl |= LM3692X_OVP_25V;419 break;420 case 29000000:421 led->boost_ctrl |= LM3692X_OVP_29V;422 break;423 default:424 dev_err(&led->client->dev, "Invalid OVP %d\n", ovp);425 return -EINVAL;426 }427 }428 429 child = device_get_next_child_node(&led->client->dev, child);430 if (!child) {431 dev_err(&led->client->dev, "No LED Child node\n");432 return -ENODEV;433 }434 435 ret = fwnode_property_read_u32(child, "reg", &led->led_enable);436 if (ret) {437 fwnode_handle_put(child);438 dev_err(&led->client->dev, "reg DT property missing\n");439 return ret;440 }441 442 ret = fwnode_property_read_u32(child, "led-max-microamp", &max_cur);443 led->led_dev.max_brightness = ret ? LED_FULL :444 lm3692x_max_brightness(led, max_cur);445 446 init_data.fwnode = child;447 init_data.devicename = led->client->name;448 init_data.default_label = ":";449 450 ret = devm_led_classdev_register_ext(&led->client->dev, &led->led_dev,451 &init_data);452 if (ret)453 dev_err(&led->client->dev, "led register err: %d\n", ret);454 455 fwnode_handle_put(init_data.fwnode);456 return ret;457}458 459static int lm3692x_probe(struct i2c_client *client)460{461 const struct i2c_device_id *id = i2c_client_get_device_id(client);462 struct lm3692x_led *led;463 int ret;464 465 led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);466 if (!led)467 return -ENOMEM;468 469 mutex_init(&led->lock);470 led->client = client;471 led->led_dev.brightness_set_blocking = lm3692x_brightness_set;472 led->model_id = id->driver_data;473 i2c_set_clientdata(client, led);474 475 led->regmap = devm_regmap_init_i2c(client, &lm3692x_regmap_config);476 if (IS_ERR(led->regmap)) {477 ret = PTR_ERR(led->regmap);478 dev_err(&client->dev, "Failed to allocate register map: %d\n",479 ret);480 return ret;481 }482 483 ret = lm3692x_probe_dt(led);484 if (ret)485 return ret;486 487 ret = lm3692x_leds_enable(led);488 if (ret)489 return ret;490 491 return 0;492}493 494static void lm3692x_remove(struct i2c_client *client)495{496 struct lm3692x_led *led = i2c_get_clientdata(client);497 498 lm3692x_leds_disable(led);499 mutex_destroy(&led->lock);500}501 502static const struct i2c_device_id lm3692x_id[] = {503 { "lm36922", LM36922_MODEL },504 { "lm36923", LM36923_MODEL },505 { }506};507MODULE_DEVICE_TABLE(i2c, lm3692x_id);508 509static const struct of_device_id of_lm3692x_leds_match[] = {510 { .compatible = "ti,lm36922", },511 { .compatible = "ti,lm36923", },512 {},513};514MODULE_DEVICE_TABLE(of, of_lm3692x_leds_match);515 516static struct i2c_driver lm3692x_driver = {517 .driver = {518 .name = "lm3692x",519 .of_match_table = of_lm3692x_leds_match,520 },521 .probe = lm3692x_probe,522 .remove = lm3692x_remove,523 .id_table = lm3692x_id,524};525module_i2c_driver(lm3692x_driver);526 527MODULE_DESCRIPTION("Texas Instruments LM3692X LED driver");528MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");529MODULE_LICENSE("GPL v2");530