1 // SPDX-License-Identifier: GPL-2.0 2 // TI LM3697 LED chip family driver 3 // Copyright (C) 2018 Texas Instruments Incorporated - https://www.ti.com/ 4 5 #include <linux/gpio/consumer.h> 6 #include <linux/i2c.h> 7 #include <linux/of.h> 8 #include <linux/of_gpio.h> 9 #include <linux/regulator/consumer.h> 10 #include <linux/leds-ti-lmu-common.h> 11 12 #define LM3697_REV 0x0 13 #define LM3697_RESET 0x1 14 #define LM3697_OUTPUT_CONFIG 0x10 15 #define LM3697_CTRL_A_RAMP 0x11 16 #define LM3697_CTRL_B_RAMP 0x12 17 #define LM3697_CTRL_A_B_RT_RAMP 0x13 18 #define LM3697_CTRL_A_B_RAMP_CFG 0x14 19 #define LM3697_CTRL_A_B_BRT_CFG 0x16 20 #define LM3697_CTRL_A_FS_CURR_CFG 0x17 21 #define LM3697_CTRL_B_FS_CURR_CFG 0x18 22 #define LM3697_PWM_CFG 0x1c 23 #define LM3697_CTRL_A_BRT_LSB 0x20 24 #define LM3697_CTRL_A_BRT_MSB 0x21 25 #define LM3697_CTRL_B_BRT_LSB 0x22 26 #define LM3697_CTRL_B_BRT_MSB 0x23 27 #define LM3697_CTRL_ENABLE 0x24 28 29 #define LM3697_SW_RESET BIT(0) 30 31 #define LM3697_CTRL_A_EN BIT(0) 32 #define LM3697_CTRL_B_EN BIT(1) 33 #define LM3697_CTRL_A_B_EN (LM3697_CTRL_A_EN | LM3697_CTRL_B_EN) 34 35 #define LM3697_MAX_LED_STRINGS 3 36 37 #define LM3697_CONTROL_A 0 38 #define LM3697_CONTROL_B 1 39 #define LM3697_MAX_CONTROL_BANKS 2 40 41 /** 42 * struct lm3697_led - 43 * @hvled_strings: Array of LED strings associated with a control bank 44 * @label: LED label 45 * @led_dev: LED class device 46 * @priv: Pointer to the device struct 47 * @lmu_data: Register and setting values for common code 48 * @control_bank: Control bank the LED is associated to. 0 is control bank A 49 * 1 is control bank B 50 */ 51 struct lm3697_led { 52 u32 hvled_strings[LM3697_MAX_LED_STRINGS]; 53 char label[LED_MAX_NAME_SIZE]; 54 struct led_classdev led_dev; 55 struct lm3697 *priv; 56 struct ti_lmu_bank lmu_data; 57 int control_bank; 58 int enabled; 59 int num_leds; 60 }; 61 62 /** 63 * struct lm3697 - 64 * @enable_gpio: Hardware enable gpio 65 * @regulator: LED supply regulator pointer 66 * @client: Pointer to the I2C client 67 * @regmap: Devices register map 68 * @dev: Pointer to the devices device struct 69 * @lock: Lock for reading/writing the device 70 * @leds: Array of LED strings 71 */ 72 struct lm3697 { 73 struct gpio_desc *enable_gpio; 74 struct regulator *regulator; 75 struct i2c_client *client; 76 struct regmap *regmap; 77 struct device *dev; 78 struct mutex lock; 79 80 int bank_cfg; 81 82 struct lm3697_led leds[]; 83 }; 84 85 static const struct reg_default lm3697_reg_defs[] = { 86 {LM3697_OUTPUT_CONFIG, 0x6}, 87 {LM3697_CTRL_A_RAMP, 0x0}, 88 {LM3697_CTRL_B_RAMP, 0x0}, 89 {LM3697_CTRL_A_B_RT_RAMP, 0x0}, 90 {LM3697_CTRL_A_B_RAMP_CFG, 0x0}, 91 {LM3697_CTRL_A_B_BRT_CFG, 0x0}, 92 {LM3697_CTRL_A_FS_CURR_CFG, 0x13}, 93 {LM3697_CTRL_B_FS_CURR_CFG, 0x13}, 94 {LM3697_PWM_CFG, 0xc}, 95 {LM3697_CTRL_A_BRT_LSB, 0x0}, 96 {LM3697_CTRL_A_BRT_MSB, 0x0}, 97 {LM3697_CTRL_B_BRT_LSB, 0x0}, 98 {LM3697_CTRL_B_BRT_MSB, 0x0}, 99 {LM3697_CTRL_ENABLE, 0x0}, 100 }; 101 102 static const struct regmap_config lm3697_regmap_config = { 103 .reg_bits = 8, 104 .val_bits = 8, 105 106 .max_register = LM3697_CTRL_ENABLE, 107 .reg_defaults = lm3697_reg_defs, 108 .num_reg_defaults = ARRAY_SIZE(lm3697_reg_defs), 109 .cache_type = REGCACHE_FLAT, 110 }; 111 112 static int lm3697_brightness_set(struct led_classdev *led_cdev, 113 enum led_brightness brt_val) 114 { 115 struct lm3697_led *led = container_of(led_cdev, struct lm3697_led, 116 led_dev); 117 int ctrl_en_val = (1 << led->control_bank); 118 int ret; 119 120 mutex_lock(&led->priv->lock); 121 122 if (brt_val == LED_OFF) { 123 ret = regmap_update_bits(led->priv->regmap, LM3697_CTRL_ENABLE, 124 ctrl_en_val, ~ctrl_en_val); 125 if (ret) { 126 dev_err(&led->priv->client->dev, "Cannot write ctrl register\n"); 127 goto brightness_out; 128 } 129 130 led->enabled = LED_OFF; 131 } else { 132 ret = ti_lmu_common_set_brightness(&led->lmu_data, brt_val); 133 if (ret) { 134 dev_err(&led->priv->client->dev, 135 "Cannot write brightness\n"); 136 goto brightness_out; 137 } 138 139 if (!led->enabled) { 140 ret = regmap_update_bits(led->priv->regmap, 141 LM3697_CTRL_ENABLE, 142 ctrl_en_val, ctrl_en_val); 143 if (ret) { 144 dev_err(&led->priv->client->dev, 145 "Cannot enable the device\n"); 146 goto brightness_out; 147 } 148 149 led->enabled = brt_val; 150 } 151 } 152 153 brightness_out: 154 mutex_unlock(&led->priv->lock); 155 return ret; 156 } 157 158 static int lm3697_init(struct lm3697 *priv) 159 { 160 struct lm3697_led *led; 161 int i, ret; 162 163 if (priv->enable_gpio) { 164 gpiod_direction_output(priv->enable_gpio, 1); 165 } else { 166 ret = regmap_write(priv->regmap, LM3697_RESET, LM3697_SW_RESET); 167 if (ret) { 168 dev_err(&priv->client->dev, "Cannot reset the device\n"); 169 goto out; 170 } 171 } 172 173 ret = regmap_write(priv->regmap, LM3697_CTRL_ENABLE, 0x0); 174 if (ret) { 175 dev_err(&priv->client->dev, "Cannot write ctrl enable\n"); 176 goto out; 177 } 178 179 ret = regmap_write(priv->regmap, LM3697_OUTPUT_CONFIG, priv->bank_cfg); 180 if (ret) 181 dev_err(&priv->client->dev, "Cannot write OUTPUT config\n"); 182 183 for (i = 0; i < LM3697_MAX_CONTROL_BANKS; i++) { 184 led = &priv->leds[i]; 185 ret = ti_lmu_common_set_ramp(&led->lmu_data); 186 if (ret) 187 dev_err(&priv->client->dev, "Setting the ramp rate failed\n"); 188 } 189 out: 190 return ret; 191 } 192 193 static int lm3697_probe_dt(struct lm3697 *priv) 194 { 195 struct fwnode_handle *child = NULL; 196 struct lm3697_led *led; 197 const char *name; 198 int control_bank; 199 size_t i = 0; 200 int ret = -EINVAL; 201 int j; 202 203 priv->enable_gpio = devm_gpiod_get_optional(&priv->client->dev, 204 "enable", GPIOD_OUT_LOW); 205 if (IS_ERR(priv->enable_gpio)) { 206 ret = PTR_ERR(priv->enable_gpio); 207 dev_err(&priv->client->dev, "Failed to get enable gpio: %d\n", 208 ret); 209 return ret; 210 } 211 212 priv->regulator = devm_regulator_get(&priv->client->dev, "vled"); 213 if (IS_ERR(priv->regulator)) 214 priv->regulator = NULL; 215 216 device_for_each_child_node(priv->dev, child) { 217 ret = fwnode_property_read_u32(child, "reg", &control_bank); 218 if (ret) { 219 dev_err(&priv->client->dev, "reg property missing\n"); 220 fwnode_handle_put(child); 221 goto child_out; 222 } 223 224 if (control_bank > LM3697_CONTROL_B) { 225 dev_err(&priv->client->dev, "reg property is invalid\n"); 226 ret = -EINVAL; 227 fwnode_handle_put(child); 228 goto child_out; 229 } 230 231 led = &priv->leds[i]; 232 233 ret = ti_lmu_common_get_brt_res(&priv->client->dev, 234 child, &led->lmu_data); 235 if (ret) 236 dev_warn(&priv->client->dev, "brightness resolution property missing\n"); 237 238 led->control_bank = control_bank; 239 led->lmu_data.regmap = priv->regmap; 240 led->lmu_data.runtime_ramp_reg = LM3697_CTRL_A_RAMP + 241 control_bank; 242 led->lmu_data.msb_brightness_reg = LM3697_CTRL_A_BRT_MSB + 243 led->control_bank * 2; 244 led->lmu_data.lsb_brightness_reg = LM3697_CTRL_A_BRT_LSB + 245 led->control_bank * 2; 246 247 led->num_leds = fwnode_property_count_u32(child, "led-sources"); 248 if (led->num_leds > LM3697_MAX_LED_STRINGS) { 249 dev_err(&priv->client->dev, "Too many LED strings defined\n"); 250 continue; 251 } 252 253 ret = fwnode_property_read_u32_array(child, "led-sources", 254 led->hvled_strings, 255 led->num_leds); 256 if (ret) { 257 dev_err(&priv->client->dev, "led-sources property missing\n"); 258 fwnode_handle_put(child); 259 goto child_out; 260 } 261 262 for (j = 0; j < led->num_leds; j++) 263 priv->bank_cfg |= 264 (led->control_bank << led->hvled_strings[j]); 265 266 ret = ti_lmu_common_get_ramp_params(&priv->client->dev, 267 child, &led->lmu_data); 268 if (ret) 269 dev_warn(&priv->client->dev, "runtime-ramp properties missing\n"); 270 271 fwnode_property_read_string(child, "linux,default-trigger", 272 &led->led_dev.default_trigger); 273 274 ret = fwnode_property_read_string(child, "label", &name); 275 if (ret) 276 snprintf(led->label, sizeof(led->label), 277 "%s::", priv->client->name); 278 else 279 snprintf(led->label, sizeof(led->label), 280 "%s:%s", priv->client->name, name); 281 282 led->priv = priv; 283 led->led_dev.name = led->label; 284 led->led_dev.max_brightness = led->lmu_data.max_brightness; 285 led->led_dev.brightness_set_blocking = lm3697_brightness_set; 286 287 ret = devm_led_classdev_register(priv->dev, &led->led_dev); 288 if (ret) { 289 dev_err(&priv->client->dev, "led register err: %d\n", 290 ret); 291 fwnode_handle_put(child); 292 goto child_out; 293 } 294 295 i++; 296 } 297 298 child_out: 299 return ret; 300 } 301 302 static int lm3697_probe(struct i2c_client *client, 303 const struct i2c_device_id *id) 304 { 305 struct lm3697 *led; 306 int count; 307 int ret; 308 309 count = device_get_child_node_count(&client->dev); 310 if (!count) { 311 dev_err(&client->dev, "LEDs are not defined in device tree!"); 312 return -ENODEV; 313 } 314 315 led = devm_kzalloc(&client->dev, struct_size(led, leds, count), 316 GFP_KERNEL); 317 if (!led) 318 return -ENOMEM; 319 320 mutex_init(&led->lock); 321 i2c_set_clientdata(client, led); 322 323 led->client = client; 324 led->dev = &client->dev; 325 led->regmap = devm_regmap_init_i2c(client, &lm3697_regmap_config); 326 if (IS_ERR(led->regmap)) { 327 ret = PTR_ERR(led->regmap); 328 dev_err(&client->dev, "Failed to allocate register map: %d\n", 329 ret); 330 return ret; 331 } 332 333 ret = lm3697_probe_dt(led); 334 if (ret) 335 return ret; 336 337 return lm3697_init(led); 338 } 339 340 static int lm3697_remove(struct i2c_client *client) 341 { 342 struct lm3697 *led = i2c_get_clientdata(client); 343 int ret; 344 345 ret = regmap_update_bits(led->regmap, LM3697_CTRL_ENABLE, 346 LM3697_CTRL_A_B_EN, 0); 347 if (ret) { 348 dev_err(&led->client->dev, "Failed to disable the device\n"); 349 return ret; 350 } 351 352 if (led->enable_gpio) 353 gpiod_direction_output(led->enable_gpio, 0); 354 355 if (led->regulator) { 356 ret = regulator_disable(led->regulator); 357 if (ret) 358 dev_err(&led->client->dev, 359 "Failed to disable regulator\n"); 360 } 361 362 mutex_destroy(&led->lock); 363 364 return 0; 365 } 366 367 static const struct i2c_device_id lm3697_id[] = { 368 { "lm3697", 0 }, 369 { } 370 }; 371 MODULE_DEVICE_TABLE(i2c, lm3697_id); 372 373 static const struct of_device_id of_lm3697_leds_match[] = { 374 { .compatible = "ti,lm3697", }, 375 {}, 376 }; 377 MODULE_DEVICE_TABLE(of, of_lm3697_leds_match); 378 379 static struct i2c_driver lm3697_driver = { 380 .driver = { 381 .name = "lm3697", 382 .of_match_table = of_lm3697_leds_match, 383 }, 384 .probe = lm3697_probe, 385 .remove = lm3697_remove, 386 .id_table = lm3697_id, 387 }; 388 module_i2c_driver(lm3697_driver); 389 390 MODULE_DESCRIPTION("Texas Instruments LM3697 LED driver"); 391 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>"); 392 MODULE_LICENSE("GPL v2"); 393