drivers/leds/leds-lm3532.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // TI LM3532 LED driver
   3 // Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
   4
   5 #include <linux/i2c.h>
   6 #include <linux/leds.h>
   7 #include <linux/slab.h>
   8 #include <linux/regmap.h>
   9 #include <linux/types.h>
  10 #include <linux/regulator/consumer.h>
  11 #include <linux/module.h>
  12 #include <uapi/linux/uleds.h>
  13 #include <linux/gpio/consumer.h>
  14
  15 #define LM3532_NAME "lm3532-led"
  16 #define LM3532_BL_MODE_MANUAL   0x00
  17 #define LM3532_BL_MODE_ALS      0x01
  18
  19 #define LM3532_REG_OUTPUT_CFG   0x10
  20 #define LM3532_REG_STARTSHUT_RAMP       0x11
  21 #define LM3532_REG_RT_RAMP      0x12
  22 #define LM3532_REG_PWM_A_CFG    0x13
  23 #define LM3532_REG_PWM_B_CFG    0x14
  24 #define LM3532_REG_PWM_C_CFG    0x15
  25 #define LM3532_REG_ZONE_CFG_A   0x16
  26 #define LM3532_REG_CTRL_A_BRT   0x17
  27 #define LM3532_REG_ZONE_CFG_B   0x18
  28 #define LM3532_REG_CTRL_B_BRT   0x19
  29 #define LM3532_REG_ZONE_CFG_C   0x1a
  30 #define LM3532_REG_CTRL_C_BRT   0x1b
  31 #define LM3532_REG_ENABLE       0x1d
  32 #define LM3532_ALS_CONFIG       0x23
  33 #define LM3532_REG_ZN_0_HI      0x60
  34 #define LM3532_REG_ZN_0_LO      0x61
  35 #define LM3532_REG_ZN_1_HI      0x62
  36 #define LM3532_REG_ZN_1_LO      0x63
  37 #define LM3532_REG_ZN_2_HI      0x64
  38 #define LM3532_REG_ZN_2_LO      0x65
  39 #define LM3532_REG_ZN_3_HI      0x66
  40 #define LM3532_REG_ZN_3_LO      0x67
  41 #define LM3532_REG_MAX          0x7e
  42
  43 /* Contorl Enable */
  44 #define LM3532_CTRL_A_ENABLE    BIT(0)
  45 #define LM3532_CTRL_B_ENABLE    BIT(1)
  46 #define LM3532_CTRL_C_ENABLE    BIT(2)
  47
  48 /* PWM Zone Control */
  49 #define LM3532_PWM_ZONE_MASK    0x7c
  50 #define LM3532_PWM_ZONE_0_EN    BIT(2)
  51 #define LM3532_PWM_ZONE_1_EN    BIT(3)
  52 #define LM3532_PWM_ZONE_2_EN    BIT(4)
  53 #define LM3532_PWM_ZONE_3_EN    BIT(5)
  54 #define LM3532_PWM_ZONE_4_EN    BIT(6)
  55
  56 /* Brightness Configuration */
  57 #define LM3532_I2C_CTRL         BIT(0)
  58 #define LM3532_ALS_CTRL         0
  59 #define LM3532_LINEAR_MAP       BIT(1)
  60 #define LM3532_ZONE_MASK        (BIT(2) | BIT(3) | BIT(4))
  61 #define LM3532_ZONE_0           0
  62 #define LM3532_ZONE_1           BIT(2)
  63 #define LM3532_ZONE_2           BIT(3)
  64 #define LM3532_ZONE_3           (BIT(2) | BIT(3))
  65 #define LM3532_ZONE_4           BIT(4)
  66
  67 #define LM3532_ENABLE_ALS       BIT(3)
  68 #define LM3532_ALS_SEL_SHIFT    6
  69
  70 /* Zone Boundary Register */
  71 #define LM3532_ALS_WINDOW_mV    2000
  72 #define LM3532_ALS_ZB_MAX       4
  73 #define LM3532_ALS_OFFSET_mV    2
  74
  75 #define LM3532_CONTROL_A        0
  76 #define LM3532_CONTROL_B        1
  77 #define LM3532_CONTROL_C        2
  78 #define LM3532_MAX_CONTROL_BANKS 3
  79 #define LM3532_MAX_LED_STRINGS  3
  80
  81 #define LM3532_OUTPUT_CFG_MASK  0x3
  82 #define LM3532_BRT_VAL_ADJUST   8
  83 #define LM3532_RAMP_DOWN_SHIFT  3
  84
  85 #define LM3532_NUM_RAMP_VALS    8
  86 #define LM3532_NUM_AVG_VALS     8
  87 #define LM3532_NUM_IMP_VALS     32
  88
  89 /*
  90  * struct lm3532_als_data
  91  * @config - value of ALS configuration register
  92  * @als1_imp_sel - value of ALS1 resistor select register
  93  * @als2_imp_sel - value of ALS2 resistor select register
  94  * @als_avrg_time - ALS averaging time
  95  * @als_input_mode - ALS input mode for brightness control
  96  * @als_vmin - Minimum ALS voltage
  97  * @als_vmax - Maximum ALS voltage
  98  * @zone_lo - values of ALS lo ZB(Zone Boundary) registers
  99  * @zone_hi - values of ALS hi ZB(Zone Boundary) registers
 100  */
 101 struct lm3532_als_data {
 102         u8 config;
 103         u8 als1_imp_sel;
 104         u8 als2_imp_sel;
 105         u8 als_avrg_time;
 106         u8 als_input_mode;
 107         u32 als_vmin;
 108         u32 als_vmax;
 109         u8 zones_lo[LM3532_ALS_ZB_MAX];
 110         u8 zones_hi[LM3532_ALS_ZB_MAX];
 111 };
 112
 113 /**
 114  * struct lm3532_led
 115  * @led_dev: led class device
 116  * @priv - Pointer the device data structure
 117  * @control_bank - Control bank the LED is associated to
 118  * @mode - Mode of the LED string
 119  * @num_leds - Number of LED strings are supported in this array
 120  * @led_strings - The LED strings supported in this array
 121  * @label - LED label
 122  */
 123 struct lm3532_led {
 124         struct led_classdev led_dev;
 125         struct lm3532_data *priv;
 126
 127         int control_bank;
 128         int mode;
 129         int num_leds;
 130         u32 led_strings[LM3532_MAX_CONTROL_BANKS];
 131         char label[LED_MAX_NAME_SIZE];
 132 };
 133
 134 /**
 135  * struct lm3532_data
 136  * @enable_gpio - Hardware enable gpio
 137  * @regulator: regulator
 138  * @client: i2c client
 139  * @regmap - Devices register map
 140  * @dev - Pointer to the devices device struct
 141  * @lock - Lock for reading/writing the device
 142  * @als_data - Pointer to the als data struct
 143  * @runtime_ramp_up - Runtime ramp up setting
 144  * @runtime_ramp_down - Runtime ramp down setting
 145  * @leds - Array of LED strings
 146  */
 147 struct lm3532_data {
 148         struct gpio_desc *enable_gpio;
 149         struct regulator *regulator;
 150         struct i2c_client *client;
 151         struct regmap *regmap;
 152         struct device *dev;
 153         struct mutex lock;
 154
 155         struct lm3532_als_data *als_data;
 156
 157         u32 runtime_ramp_up;
 158         u32 runtime_ramp_down;
 159
 160         struct lm3532_led leds[];
 161 };
 162
 163 static const struct reg_default lm3532_reg_defs[] = {
 164         {LM3532_REG_OUTPUT_CFG, 0xe4},
 165         {LM3532_REG_STARTSHUT_RAMP, 0xc0},
 166         {LM3532_REG_RT_RAMP, 0xc0},
 167         {LM3532_REG_PWM_A_CFG, 0x82},
 168         {LM3532_REG_PWM_B_CFG, 0x82},
 169         {LM3532_REG_PWM_C_CFG, 0x82},
 170         {LM3532_REG_ZONE_CFG_A, 0xf1},
 171         {LM3532_REG_CTRL_A_BRT, 0xf3},
 172         {LM3532_REG_ZONE_CFG_B, 0xf1},
 173         {LM3532_REG_CTRL_B_BRT, 0xf3},
 174         {LM3532_REG_ZONE_CFG_C, 0xf1},
 175         {LM3532_REG_CTRL_C_BRT, 0xf3},
 176         {LM3532_REG_ENABLE, 0xf8},
 177         {LM3532_ALS_CONFIG, 0x44},
 178         {LM3532_REG_ZN_0_HI, 0x35},
 179         {LM3532_REG_ZN_0_LO, 0x33},
 180         {LM3532_REG_ZN_1_HI, 0x6a},
 181         {LM3532_REG_ZN_1_LO, 0x66},
 182         {LM3532_REG_ZN_2_HI, 0xa1},
 183         {LM3532_REG_ZN_2_LO, 0x99},
 184         {LM3532_REG_ZN_3_HI, 0xdc},
 185         {LM3532_REG_ZN_3_LO, 0xcc},
 186 };
 187
 188 static const struct regmap_config lm3532_regmap_config = {
 189         .reg_bits = 8,
 190         .val_bits = 8,
 191
 192         .max_register = LM3532_REG_MAX,
 193         .reg_defaults = lm3532_reg_defs,
 194         .num_reg_defaults = ARRAY_SIZE(lm3532_reg_defs),
 195         .cache_type = REGCACHE_FLAT,
 196 };
 197
 198 const static int als_imp_table[LM3532_NUM_IMP_VALS] = {37000, 18500, 12330,
 199                                                        92500, 7400, 6170, 5290,
 200                                                        4630, 4110, 3700, 3360,
 201                                                        3080, 2850, 2640, 2440,
 202                                                        2310, 2180, 2060, 1950,
 203                                                        1850, 1760, 1680, 1610,
 204                                                        1540, 1480, 1420, 1370,
 205                                                        1320, 1280, 1230, 1190};
 206 static int lm3532_get_als_imp_index(int als_imped)
 207 {
 208         int i;
 209
 210         if (als_imped > als_imp_table[1])
 211                 return 0;
 212
 213         if (als_imped < als_imp_table[LM3532_NUM_IMP_VALS - 1])
 214                 return LM3532_NUM_IMP_VALS - 1;
 215
 216         for (i = 1; i < LM3532_NUM_IMP_VALS; i++) {
 217                 if (als_imped == als_imp_table[i])
 218                         return i;
 219
 220                 /* Find an approximate index by looking up the table */
 221                 if (als_imped < als_imp_table[i - 1] &&
 222                     als_imped > als_imp_table[i]) {
 223                         if (als_imped - als_imp_table[i - 1] <
 224                             als_imp_table[i] - als_imped)
 225                                 return i + 1;
 226                         else
 227                                 return i;
 228                 }
 229         }
 230
 231         return -EINVAL;
 232 }
 233
 234 static int lm3532_get_index(const int table[], int size, int value)
 235 {
 236         int i;
 237
 238         for (i = 1; i < size; i++) {
 239                 if (value == table[i])
 240                         return i;
 241
 242                 /* Find an approximate index by looking up the table */
 243                 if (value > table[i - 1] &&
 244                     value < table[i]) {
 245                         if (value - table[i - 1] < table[i] - value)
 246                                 return i - 1;
 247                         else
 248                                 return i;
 249                 }
 250         }
 251
 252         return -EINVAL;
 253 }
 254
 255 const static int als_avrg_table[LM3532_NUM_AVG_VALS] = {17920, 35840, 71680,
 256                                                         1433360, 286720, 573440,
 257                                                         1146880, 2293760};
 258 static int lm3532_get_als_avg_index(int avg_time)
 259 {
 260         if (avg_time <= als_avrg_table[0])
 261                 return 0;
 262
 263         if (avg_time > als_avrg_table[LM3532_NUM_AVG_VALS - 1])
 264                 return LM3532_NUM_AVG_VALS - 1;
 265
 266         return lm3532_get_index(&als_avrg_table[0], LM3532_NUM_AVG_VALS,
 267                                 avg_time);
 268 }
 269
 270 const static int ramp_table[LM3532_NUM_RAMP_VALS] = { 8, 1024, 2048, 4096, 8192,
 271                                                      16384, 32768, 65536};
 272 static int lm3532_get_ramp_index(int ramp_time)
 273 {
 274         if (ramp_time <= ramp_table[0])
 275                 return 0;
 276
 277         if (ramp_time > ramp_table[LM3532_NUM_RAMP_VALS - 1])
 278                 return LM3532_NUM_RAMP_VALS - 1;
 279
 280         return lm3532_get_index(&ramp_table[0], LM3532_NUM_RAMP_VALS,
 281                                 ramp_time);
 282 }
 283
 284 static int lm3532_led_enable(struct lm3532_led *led_data)
 285 {
 286         int ctrl_en_val = BIT(led_data->control_bank);
 287         int ret;
 288
 289         ret = regmap_update_bits(led_data->priv->regmap, LM3532_REG_ENABLE,
 290                                          ctrl_en_val, ctrl_en_val);
 291         if (ret) {
 292                 dev_err(led_data->priv->dev, "Failed to set ctrl:%d\n", ret);
 293                 return ret;
 294         }
 295
 296         return regulator_enable(led_data->priv->regulator);
 297 }
 298
 299 static int lm3532_led_disable(struct lm3532_led *led_data)
 300 {
 301         int ctrl_en_val = BIT(led_data->control_bank);
 302         int ret;
 303
 304         ret = regmap_update_bits(led_data->priv->regmap, LM3532_REG_ENABLE,
 305                                          ctrl_en_val, ~ctrl_en_val);
 306         if (ret) {
 307                 dev_err(led_data->priv->dev, "Failed to set ctrl:%d\n", ret);
 308                 return ret;
 309         }
 310
 311         return regulator_disable(led_data->priv->regulator);
 312 }
 313
 314 static int lm3532_brightness_set(struct led_classdev *led_cdev,
 315                                  enum led_brightness brt_val)
 316 {
 317         struct lm3532_led *led =
 318                         container_of(led_cdev, struct lm3532_led, led_dev);
 319         u8 brightness_reg;
 320         int ret;
 321
 322         mutex_lock(&led->priv->lock);
 323
 324         if (led->mode == LM3532_BL_MODE_ALS) {
 325                 if (brt_val > LED_OFF)
 326                         ret = lm3532_led_enable(led);
 327                 else
 328                         ret = lm3532_led_disable(led);
 329
 330                 goto unlock;
 331         }
 332
 333         if (brt_val == LED_OFF) {
 334                 ret = lm3532_led_disable(led);
 335                 goto unlock;
 336         }
 337
 338         ret = lm3532_led_enable(led);
 339         if (ret)
 340                 goto unlock;
 341
 342         brightness_reg = LM3532_REG_CTRL_A_BRT + led->control_bank * 2;
 343         brt_val = brt_val / LM3532_BRT_VAL_ADJUST;
 344
 345         ret = regmap_write(led->priv->regmap, brightness_reg, brt_val);
 346
 347 unlock:
 348         mutex_unlock(&led->priv->lock);
 349         return ret;
 350 }
 351
 352 static int lm3532_init_registers(struct lm3532_led *led)
 353 {
 354         struct lm3532_data *drvdata = led->priv;
 355         unsigned int runtime_ramp_val;
 356         unsigned int output_cfg_val = 0;
 357         unsigned int output_cfg_shift = 0;
 358         unsigned int output_cfg_mask = 0;
 359         int ret, i;
 360
 361         for (i = 0; i < led->num_leds; i++) {
 362                 output_cfg_shift = led->led_strings[i] * 2;
 363                 output_cfg_val |= (led->control_bank << output_cfg_shift);
 364                 output_cfg_mask |= LM3532_OUTPUT_CFG_MASK << output_cfg_shift;
 365         }
 366
 367         ret = regmap_update_bits(drvdata->regmap, LM3532_REG_OUTPUT_CFG,
 368                                  output_cfg_mask, output_cfg_val);
 369         if (ret)
 370                 return ret;
 371
 372         runtime_ramp_val = drvdata->runtime_ramp_up |
 373                          (drvdata->runtime_ramp_down << LM3532_RAMP_DOWN_SHIFT);
 374
 375         return regmap_write(drvdata->regmap, LM3532_REG_RT_RAMP,
 376                             runtime_ramp_val);
 377 }
 378
 379 static int lm3532_als_configure(struct lm3532_data *priv,
 380                                 struct lm3532_led *led)
 381 {
 382         struct lm3532_als_data *als = priv->als_data;
 383         u32 als_vmin, als_vmax, als_vstep;
 384         int zone_reg = LM3532_REG_ZN_0_HI;
 385         int brightnes_config_reg;
 386         int ret;
 387         int i;
 388
 389         als_vmin = als->als_vmin;
 390         als_vmax = als->als_vmax;
 391
 392         als_vstep = (als_vmax - als_vmin) / ((LM3532_ALS_ZB_MAX + 1) * 2);
 393
 394         for (i = 0; i < LM3532_ALS_ZB_MAX; i++) {
 395                 als->zones_lo[i] = ((als_vmin + als_vstep + (i * als_vstep)) *
 396                                 LED_FULL) / 1000;
 397                 als->zones_hi[i] = ((als_vmin + LM3532_ALS_OFFSET_mV +
 398                                 als_vstep + (i * als_vstep)) * LED_FULL) / 1000;
 399
 400                 zone_reg = LM3532_REG_ZN_0_HI + i * 2;
 401                 ret = regmap_write(priv->regmap, zone_reg, als->zones_lo[i]);
 402                 if (ret)
 403                         return ret;
 404
 405                 zone_reg += 1;
 406                 ret = regmap_write(priv->regmap, zone_reg, als->zones_hi[i]);
 407                 if (ret)
 408                         return ret;
 409         }
 410
 411         als->config = (als->als_avrg_time | (LM3532_ENABLE_ALS) |
 412                 (als->als_input_mode << LM3532_ALS_SEL_SHIFT));
 413
 414         ret = regmap_write(priv->regmap, LM3532_ALS_CONFIG, als->config);
 415         if (ret)
 416                 return ret;
 417
 418         brightnes_config_reg = LM3532_REG_ZONE_CFG_A + led->control_bank * 2;
 419
 420         return regmap_update_bits(priv->regmap, brightnes_config_reg,
 421                                   LM3532_I2C_CTRL, LM3532_ALS_CTRL);
 422 }
 423
 424 static int lm3532_parse_als(struct lm3532_data *priv)
 425 {
 426         struct lm3532_als_data *als;
 427         int als_avg_time;
 428         int als_impedance;
 429         int ret;
 430
 431         als = devm_kzalloc(priv->dev, sizeof(*als), GFP_KERNEL);
 432         if (als == NULL)
 433                 return -ENOMEM;
 434
 435         ret = device_property_read_u32(&priv->client->dev, "ti,als-vmin",
 436                                        &als->als_vmin);
 437         if (ret)
 438                 als->als_vmin = 0;
 439
 440         ret = device_property_read_u32(&priv->client->dev, "ti,als-vmax",
 441                                        &als->als_vmax);
 442         if (ret)
 443                 als->als_vmax = LM3532_ALS_WINDOW_mV;
 444
 445         if (als->als_vmax > LM3532_ALS_WINDOW_mV) {
 446                 ret = -EINVAL;
 447                 return ret;
 448         }
 449
 450         ret = device_property_read_u32(&priv->client->dev, "ti,als1-imp-sel",
 451                                       &als_impedance);
 452         if (ret)
 453                 als->als1_imp_sel = 0;
 454         else
 455                 als->als1_imp_sel = lm3532_get_als_imp_index(als_impedance);
 456
 457         ret = device_property_read_u32(&priv->client->dev, "ti,als2-imp-sel",
 458                                       &als_impedance);
 459         if (ret)
 460                 als->als2_imp_sel = 0;
 461         else
 462                 als->als2_imp_sel = lm3532_get_als_imp_index(als_impedance);
 463
 464         ret = device_property_read_u32(&priv->client->dev, "ti,als-avrg-time-us",
 465                                       &als_avg_time);
 466         if (ret)
 467                 als->als_avrg_time = 0;
 468         else
 469                 als->als_avrg_time = lm3532_get_als_avg_index(als_avg_time);
 470
 471         ret = device_property_read_u8(&priv->client->dev, "ti,als-input-mode",
 472                                       &als->als_input_mode);
 473         if (ret)
 474                 als->als_input_mode = 0;
 475
 476         if (als->als_input_mode > LM3532_BL_MODE_ALS) {
 477                 ret = -EINVAL;
 478                 return ret;
 479         }
 480
 481         priv->als_data = als;
 482
 483         return ret;
 484 }
 485
 486 static int lm3532_parse_node(struct lm3532_data *priv)
 487 {
 488         struct fwnode_handle *child = NULL;
 489         struct lm3532_led *led;
 490         const char *name;
 491         int control_bank;
 492         u32 ramp_time;
 493         size_t i = 0;
 494         int ret;
 495
 496         priv->enable_gpio = devm_gpiod_get_optional(&priv->client->dev,
 497                                                    "enable", GPIOD_OUT_LOW);
 498         if (IS_ERR(priv->enable_gpio))
 499                 priv->enable_gpio = NULL;
 500
 501         priv->regulator = devm_regulator_get(&priv->client->dev, "vin");
 502         if (IS_ERR(priv->regulator))
 503                 priv->regulator = NULL;
 504
 505         ret = device_property_read_u32(&priv->client->dev, "ramp-up-us",
 506                                        &ramp_time);
 507         if (ret)
 508                 dev_info(&priv->client->dev, "ramp-up-ms property missing\n");
 509         else
 510                 priv->runtime_ramp_up = lm3532_get_ramp_index(ramp_time);
 511
 512         ret = device_property_read_u32(&priv->client->dev, "ramp-down-us",
 513                                        &ramp_time);
 514         if (ret)
 515                 dev_info(&priv->client->dev, "ramp-down-ms property missing\n");
 516         else
 517                 priv->runtime_ramp_down = lm3532_get_ramp_index(ramp_time);
 518
 519         device_for_each_child_node(priv->dev, child) {
 520                 led = &priv->leds[i];
 521
 522                 ret = fwnode_property_read_u32(child, "reg", &control_bank);
 523                 if (ret) {
 524                         dev_err(&priv->client->dev, "reg property missing\n");
 525                         fwnode_handle_put(child);
 526                         goto child_out;
 527                 }
 528
 529                 if (control_bank > LM3532_CONTROL_C) {
 530                         dev_err(&priv->client->dev, "Control bank invalid\n");
 531                         continue;
 532                 }
 533
 534                 led->control_bank = control_bank;
 535
 536                 ret = fwnode_property_read_u32(child, "ti,led-mode",
 537                                                &led->mode);
 538                 if (ret) {
 539                         dev_err(&priv->client->dev, "ti,led-mode property missing\n");
 540                         fwnode_handle_put(child);
 541                         goto child_out;
 542                 }
 543
 544                 if (led->mode == LM3532_BL_MODE_ALS) {
 545                         ret = lm3532_parse_als(priv);
 546                         if (ret)
 547                                 dev_err(&priv->client->dev, "Failed to parse als\n");
 548                         else
 549                                 lm3532_als_configure(priv, led);
 550                 }
 551
 552                 led->num_leds = fwnode_property_read_u32_array(child,
 553                                                                "led-sources",
 554                                                                NULL, 0);
 555
 556                 if (led->num_leds > LM3532_MAX_LED_STRINGS) {
 557                         dev_err(&priv->client->dev, "To many LED string defined\n");
 558                         continue;
 559                 }
 560
 561                 ret = fwnode_property_read_u32_array(child, "led-sources",
 562                                                     led->led_strings,
 563                                                     led->num_leds);
 564                 if (ret) {
 565                         dev_err(&priv->client->dev, "led-sources property missing\n");
 566                         fwnode_handle_put(child);
 567                         goto child_out;
 568                 }
 569
 570                 fwnode_property_read_string(child, "linux,default-trigger",
 571                                             &led->led_dev.default_trigger);
 572
 573                 ret = fwnode_property_read_string(child, "label", &name);
 574                 if (ret)
 575                         snprintf(led->label, sizeof(led->label),
 576                                 "%s::", priv->client->name);
 577                 else
 578                         snprintf(led->label, sizeof(led->label),
 579                                  "%s:%s", priv->client->name, name);
 580
 581                 led->priv = priv;
 582                 led->led_dev.name = led->label;
 583                 led->led_dev.brightness_set_blocking = lm3532_brightness_set;
 584
 585                 ret = devm_led_classdev_register(priv->dev, &led->led_dev);
 586                 if (ret) {
 587                         dev_err(&priv->client->dev, "led register err: %d\n",
 588                                 ret);
 589                         fwnode_handle_put(child);
 590                         goto child_out;
 591                 }
 592
 593                 lm3532_init_registers(led);
 594
 595                 i++;
 596         }
 597
 598 child_out:
 599         return ret;
 600 }
 601
 602 static int lm3532_probe(struct i2c_client *client,
 603                            const struct i2c_device_id *id)
 604 {
 605         struct lm3532_data *drvdata;
 606         int ret = 0;
 607         int count;
 608
 609         count = device_get_child_node_count(&client->dev);
 610         if (!count) {
 611                 dev_err(&client->dev, "LEDs are not defined in device tree!");
 612                 return -ENODEV;
 613         }
 614
 615         drvdata = devm_kzalloc(&client->dev, struct_size(drvdata, leds, count),
 616                            GFP_KERNEL);
 617         if (drvdata == NULL)
 618                 return -ENOMEM;
 619
 620         drvdata->client = client;
 621         drvdata->dev = &client->dev;
 622
 623         drvdata->regmap = devm_regmap_init_i2c(client, &lm3532_regmap_config);
 624         if (IS_ERR(drvdata->regmap)) {
 625                 ret = PTR_ERR(drvdata->regmap);
 626                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
 627                         ret);
 628                 return ret;
 629         }
 630
 631         mutex_init(&drvdata->lock);
 632         i2c_set_clientdata(client, drvdata);
 633
 634         ret = lm3532_parse_node(drvdata);
 635         if (ret) {
 636                 dev_err(&client->dev, "Failed to parse node\n");
 637                 return ret;
 638         }
 639
 640         if (drvdata->enable_gpio)
 641                 gpiod_direction_output(drvdata->enable_gpio, 1);
 642
 643         return ret;
 644 }
 645
 646 static int lm3532_remove(struct i2c_client *client)
 647 {
 648         struct lm3532_data *drvdata = i2c_get_clientdata(client);
 649
 650         mutex_destroy(&drvdata->lock);
 651
 652         if (drvdata->enable_gpio)
 653                 gpiod_direction_output(drvdata->enable_gpio, 0);
 654
 655         return 0;
 656 }
 657
 658 static const struct of_device_id of_lm3532_leds_match[] = {
 659         { .compatible = "ti,lm3532", },
 660         {},
 661 };
 662 MODULE_DEVICE_TABLE(of, of_lm3532_leds_match);
 663
 664 static const struct i2c_device_id lm3532_id[] = {
 665         {LM3532_NAME, 0},
 666         {}
 667 };
 668 MODULE_DEVICE_TABLE(i2c, lm3532_id);
 669
 670 static struct i2c_driver lm3532_i2c_driver = {
 671         .probe = lm3532_probe,
 672         .remove = lm3532_remove,
 673         .id_table = lm3532_id,
 674         .driver = {
 675                 .name = LM3532_NAME,
 676                 .of_match_table = of_lm3532_leds_match,
 677         },
 678 };
 679 module_i2c_driver(lm3532_i2c_driver);
 680
 681 MODULE_DESCRIPTION("Back Light driver for LM3532");
 682 MODULE_LICENSE("GPL v2");
 683 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");