drivers/regulator/max77686.c

   1 /*
   2  * max77686.c - Regulator driver for the Maxim 77686
   3  *
   4  * Copyright (C) 2012 Samsung Electronics
   5  * Chiwoong Byun <woong.byun@smasung.com>
   6  * Jonghwa Lee <jonghwa3.lee@samsung.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  *
  22  * This driver is based on max8997.c
  23  */
  24
  25 #include <linux/kernel.h>
  26 #include <linux/bug.h>
  27 #include <linux/err.h>
  28 #include <linux/gpio.h>
  29 #include <linux/slab.h>
  30 #include <linux/platform_device.h>
  31 #include <linux/regulator/driver.h>
  32 #include <linux/regulator/machine.h>
  33 #include <linux/regulator/of_regulator.h>
  34 #include <linux/mfd/max77686.h>
  35 #include <linux/mfd/max77686-private.h>
  36
  37 #define MAX77686_LDO_MINUV      800000
  38 #define MAX77686_LDO_UVSTEP     50000
  39 #define MAX77686_LDO_LOW_MINUV  800000
  40 #define MAX77686_LDO_LOW_UVSTEP 25000
  41 #define MAX77686_BUCK_MINUV     750000
  42 #define MAX77686_BUCK_UVSTEP    50000
  43 #define MAX77686_RAMP_DELAY     100000                  /* uV/us */
  44 #define MAX77686_DVS_RAMP_DELAY 27500                   /* uV/us */
  45 #define MAX77686_DVS_MINUV      600000
  46 #define MAX77686_DVS_UVSTEP     12500
  47
  48 #define MAX77686_OPMODE_SHIFT   6
  49 #define MAX77686_OPMODE_BUCK234_SHIFT   4
  50 #define MAX77686_OPMODE_MASK    0x3
  51
  52 #define MAX77686_VSEL_MASK      0x3F
  53 #define MAX77686_DVS_VSEL_MASK  0xFF
  54
  55 #define MAX77686_RAMP_RATE_MASK 0xC0
  56
  57 #define MAX77686_REGULATORS     MAX77686_REG_MAX
  58 #define MAX77686_LDOS           26
  59
  60 enum max77686_ramp_rate {
  61         RAMP_RATE_13P75MV,
  62         RAMP_RATE_27P5MV,
  63         RAMP_RATE_55MV,
  64         RAMP_RATE_NO_CTRL,      /* 100mV/us */
  65 };
  66
  67 struct max77686_data {
  68         unsigned int opmode[MAX77686_REGULATORS];
  69 };
  70
  71 /* Some BUCKS supports Normal[ON/OFF] mode during suspend */
  72 static int max77686_buck_set_suspend_disable(struct regulator_dev *rdev)
  73 {
  74         unsigned int val;
  75         struct max77686_data *max77686 = rdev_get_drvdata(rdev);
  76         int ret, id = rdev_get_id(rdev);
  77
  78         if (id == MAX77686_BUCK1)
  79                 val = 0x1;
  80         else
  81                 val = 0x1 << MAX77686_OPMODE_BUCK234_SHIFT;
  82
  83         ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
  84                                  rdev->desc->enable_mask, val);
  85         if (ret)
  86                 return ret;
  87
  88         max77686->opmode[id] = val;
  89         return 0;
  90 }
  91
  92 /* Some LDOs supports [LPM/Normal]ON mode during suspend state */
  93 static int max77686_set_suspend_mode(struct regulator_dev *rdev,
  94                                      unsigned int mode)
  95 {
  96         struct max77686_data *max77686 = rdev_get_drvdata(rdev);
  97         unsigned int val;
  98         int ret, id = rdev_get_id(rdev);
  99
 100         /* BUCK[5-9] doesn't support this feature */
 101         if (id >= MAX77686_BUCK5)
 102                 return 0;
 103
 104         switch (mode) {
 105         case REGULATOR_MODE_IDLE:                       /* ON in LP Mode */
 106                 val = 0x2 << MAX77686_OPMODE_SHIFT;
 107                 break;
 108         case REGULATOR_MODE_NORMAL:                     /* ON in Normal Mode */
 109                 val = 0x3 << MAX77686_OPMODE_SHIFT;
 110                 break;
 111         default:
 112                 pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
 113                         rdev->desc->name, mode);
 114                 return -EINVAL;
 115         }
 116
 117         ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 118                                   rdev->desc->enable_mask, val);
 119         if (ret)
 120                 return ret;
 121
 122         max77686->opmode[id] = val;
 123         return 0;
 124 }
 125
 126 /* Some LDOs supports LPM-ON/OFF/Normal-ON mode during suspend state */
 127 static int max77686_ldo_set_suspend_mode(struct regulator_dev *rdev,
 128                                      unsigned int mode)
 129 {
 130         unsigned int val;
 131         struct max77686_data *max77686 = rdev_get_drvdata(rdev);
 132         int ret;
 133
 134         switch (mode) {
 135         case REGULATOR_MODE_STANDBY:                    /* switch off */
 136                 val = 0x1 << MAX77686_OPMODE_SHIFT;
 137                 break;
 138         case REGULATOR_MODE_IDLE:                       /* ON in LP Mode */
 139                 val = 0x2 << MAX77686_OPMODE_SHIFT;
 140                 break;
 141         case REGULATOR_MODE_NORMAL:                     /* ON in Normal Mode */
 142                 val = 0x3 << MAX77686_OPMODE_SHIFT;
 143                 break;
 144         default:
 145                 pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
 146                         rdev->desc->name, mode);
 147                 return -EINVAL;
 148         }
 149
 150         ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 151                                  rdev->desc->enable_mask, val);
 152         if (ret)
 153                 return ret;
 154
 155         max77686->opmode[rdev_get_id(rdev)] = val;
 156         return 0;
 157 }
 158
 159 static int max77686_enable(struct regulator_dev *rdev)
 160 {
 161         struct max77686_data *max77686 = rdev_get_drvdata(rdev);
 162
 163         return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 164                                   rdev->desc->enable_mask,
 165                                   max77686->opmode[rdev_get_id(rdev)]);
 166 }
 167
 168 static int max77686_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
 169 {
 170         unsigned int ramp_value = RAMP_RATE_NO_CTRL;
 171
 172         switch (ramp_delay) {
 173         case 1 ... 13750:
 174                 ramp_value = RAMP_RATE_13P75MV;
 175                 break;
 176         case 13751 ... 27500:
 177                 ramp_value = RAMP_RATE_27P5MV;
 178                 break;
 179         case 27501 ... 55000:
 180                 ramp_value = RAMP_RATE_55MV;
 181                 break;
 182         case 55001 ... 100000:
 183                 break;
 184         default:
 185                 pr_warn("%s: ramp_delay: %d not supported, setting 100000\n",
 186                         rdev->desc->name, ramp_delay);
 187         }
 188
 189         return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 190                                   MAX77686_RAMP_RATE_MASK, ramp_value << 6);
 191 }
 192
 193 static struct regulator_ops max77686_ops = {
 194         .list_voltage           = regulator_list_voltage_linear,
 195         .map_voltage            = regulator_map_voltage_linear,
 196         .is_enabled             = regulator_is_enabled_regmap,
 197         .enable                 = max77686_enable,
 198         .disable                = regulator_disable_regmap,
 199         .get_voltage_sel        = regulator_get_voltage_sel_regmap,
 200         .set_voltage_sel        = regulator_set_voltage_sel_regmap,
 201         .set_voltage_time_sel   = regulator_set_voltage_time_sel,
 202         .set_suspend_mode       = max77686_set_suspend_mode,
 203 };
 204
 205 static struct regulator_ops max77686_ldo_ops = {
 206         .list_voltage           = regulator_list_voltage_linear,
 207         .map_voltage            = regulator_map_voltage_linear,
 208         .is_enabled             = regulator_is_enabled_regmap,
 209         .enable                 = max77686_enable,
 210         .disable                = regulator_disable_regmap,
 211         .get_voltage_sel        = regulator_get_voltage_sel_regmap,
 212         .set_voltage_sel        = regulator_set_voltage_sel_regmap,
 213         .set_voltage_time_sel   = regulator_set_voltage_time_sel,
 214         .set_suspend_mode       = max77686_ldo_set_suspend_mode,
 215 };
 216
 217 static struct regulator_ops max77686_buck1_ops = {
 218         .list_voltage           = regulator_list_voltage_linear,
 219         .map_voltage            = regulator_map_voltage_linear,
 220         .is_enabled             = regulator_is_enabled_regmap,
 221         .enable                 = max77686_enable,
 222         .disable                = regulator_disable_regmap,
 223         .get_voltage_sel        = regulator_get_voltage_sel_regmap,
 224         .set_voltage_sel        = regulator_set_voltage_sel_regmap,
 225         .set_voltage_time_sel   = regulator_set_voltage_time_sel,
 226         .set_suspend_disable    = max77686_buck_set_suspend_disable,
 227 };
 228
 229 static struct regulator_ops max77686_buck_dvs_ops = {
 230         .list_voltage           = regulator_list_voltage_linear,
 231         .map_voltage            = regulator_map_voltage_linear,
 232         .is_enabled             = regulator_is_enabled_regmap,
 233         .enable                 = max77686_enable,
 234         .disable                = regulator_disable_regmap,
 235         .get_voltage_sel        = regulator_get_voltage_sel_regmap,
 236         .set_voltage_sel        = regulator_set_voltage_sel_regmap,
 237         .set_voltage_time_sel   = regulator_set_voltage_time_sel,
 238         .set_ramp_delay         = max77686_set_ramp_delay,
 239         .set_suspend_disable    = max77686_buck_set_suspend_disable,
 240 };
 241
 242 #define regulator_desc_ldo(num)         {                               \
 243         .name           = "LDO"#num,                                    \
 244         .id             = MAX77686_LDO##num,                            \
 245         .ops            = &max77686_ops,                                \
 246         .type           = REGULATOR_VOLTAGE,                            \
 247         .owner          = THIS_MODULE,                                  \
 248         .min_uV         = MAX77686_LDO_MINUV,                           \
 249         .uV_step        = MAX77686_LDO_UVSTEP,                          \
 250         .ramp_delay     = MAX77686_RAMP_DELAY,                          \
 251         .n_voltages     = MAX77686_VSEL_MASK + 1,                       \
 252         .vsel_reg       = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 253         .vsel_mask      = MAX77686_VSEL_MASK,                           \
 254         .enable_reg     = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 255         .enable_mask    = MAX77686_OPMODE_MASK                          \
 256                         << MAX77686_OPMODE_SHIFT,                       \
 257 }
 258 #define regulator_desc_lpm_ldo(num)     {                               \
 259         .name           = "LDO"#num,                                    \
 260         .id             = MAX77686_LDO##num,                            \
 261         .ops            = &max77686_ldo_ops,                            \
 262         .type           = REGULATOR_VOLTAGE,                            \
 263         .owner          = THIS_MODULE,                                  \
 264         .min_uV         = MAX77686_LDO_MINUV,                           \
 265         .uV_step        = MAX77686_LDO_UVSTEP,                          \
 266         .ramp_delay     = MAX77686_RAMP_DELAY,                          \
 267         .n_voltages     = MAX77686_VSEL_MASK + 1,                       \
 268         .vsel_reg       = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 269         .vsel_mask      = MAX77686_VSEL_MASK,                           \
 270         .enable_reg     = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 271         .enable_mask    = MAX77686_OPMODE_MASK                          \
 272                         << MAX77686_OPMODE_SHIFT,                       \
 273 }
 274 #define regulator_desc_ldo_low(num)             {                       \
 275         .name           = "LDO"#num,                                    \
 276         .id             = MAX77686_LDO##num,                            \
 277         .ops            = &max77686_ldo_ops,                            \
 278         .type           = REGULATOR_VOLTAGE,                            \
 279         .owner          = THIS_MODULE,                                  \
 280         .min_uV         = MAX77686_LDO_LOW_MINUV,                       \
 281         .uV_step        = MAX77686_LDO_LOW_UVSTEP,                      \
 282         .ramp_delay     = MAX77686_RAMP_DELAY,                          \
 283         .n_voltages     = MAX77686_VSEL_MASK + 1,                       \
 284         .vsel_reg       = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 285         .vsel_mask      = MAX77686_VSEL_MASK,                           \
 286         .enable_reg     = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 287         .enable_mask    = MAX77686_OPMODE_MASK                          \
 288                         << MAX77686_OPMODE_SHIFT,                       \
 289 }
 290 #define regulator_desc_ldo1_low(num)            {                       \
 291         .name           = "LDO"#num,                                    \
 292         .id             = MAX77686_LDO##num,                            \
 293         .ops            = &max77686_ops,                                \
 294         .type           = REGULATOR_VOLTAGE,                            \
 295         .owner          = THIS_MODULE,                                  \
 296         .min_uV         = MAX77686_LDO_LOW_MINUV,                       \
 297         .uV_step        = MAX77686_LDO_LOW_UVSTEP,                      \
 298         .ramp_delay     = MAX77686_RAMP_DELAY,                          \
 299         .n_voltages     = MAX77686_VSEL_MASK + 1,                       \
 300         .vsel_reg       = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 301         .vsel_mask      = MAX77686_VSEL_MASK,                           \
 302         .enable_reg     = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 303         .enable_mask    = MAX77686_OPMODE_MASK                          \
 304                         << MAX77686_OPMODE_SHIFT,                       \
 305 }
 306 #define regulator_desc_buck(num)                {                       \
 307         .name           = "BUCK"#num,                                   \
 308         .id             = MAX77686_BUCK##num,                           \
 309         .ops            = &max77686_ops,                                \
 310         .type           = REGULATOR_VOLTAGE,                            \
 311         .owner          = THIS_MODULE,                                  \
 312         .min_uV         = MAX77686_BUCK_MINUV,                          \
 313         .uV_step        = MAX77686_BUCK_UVSTEP,                         \
 314         .ramp_delay     = MAX77686_RAMP_DELAY,                          \
 315         .n_voltages     = MAX77686_VSEL_MASK + 1,                       \
 316         .vsel_reg       = MAX77686_REG_BUCK5OUT + (num - 5) * 2,        \
 317         .vsel_mask      = MAX77686_VSEL_MASK,                           \
 318         .enable_reg     = MAX77686_REG_BUCK5CTRL + (num - 5) * 2,       \
 319         .enable_mask    = MAX77686_OPMODE_MASK,                         \
 320 }
 321 #define regulator_desc_buck1(num)               {                       \
 322         .name           = "BUCK"#num,                                   \
 323         .id             = MAX77686_BUCK##num,                           \
 324         .ops            = &max77686_buck1_ops,                          \
 325         .type           = REGULATOR_VOLTAGE,                            \
 326         .owner          = THIS_MODULE,                                  \
 327         .min_uV         = MAX77686_BUCK_MINUV,                          \
 328         .uV_step        = MAX77686_BUCK_UVSTEP,                         \
 329         .ramp_delay     = MAX77686_RAMP_DELAY,                          \
 330         .n_voltages     = MAX77686_VSEL_MASK + 1,                       \
 331         .vsel_reg       = MAX77686_REG_BUCK1OUT,                        \
 332         .vsel_mask      = MAX77686_VSEL_MASK,                           \
 333         .enable_reg     = MAX77686_REG_BUCK1CTRL,                       \
 334         .enable_mask    = MAX77686_OPMODE_MASK,                         \
 335 }
 336 #define regulator_desc_buck_dvs(num)            {                       \
 337         .name           = "BUCK"#num,                                   \
 338         .id             = MAX77686_BUCK##num,                           \
 339         .ops            = &max77686_buck_dvs_ops,                       \
 340         .type           = REGULATOR_VOLTAGE,                            \
 341         .owner          = THIS_MODULE,                                  \
 342         .min_uV         = MAX77686_DVS_MINUV,                           \
 343         .uV_step        = MAX77686_DVS_UVSTEP,                          \
 344         .ramp_delay     = MAX77686_DVS_RAMP_DELAY,                      \
 345         .n_voltages     = MAX77686_DVS_VSEL_MASK + 1,                   \
 346         .vsel_reg       = MAX77686_REG_BUCK2DVS1 + (num - 2) * 10,      \
 347         .vsel_mask      = MAX77686_DVS_VSEL_MASK,                       \
 348         .enable_reg     = MAX77686_REG_BUCK2CTRL1 + (num - 2) * 10,     \
 349         .enable_mask    = MAX77686_OPMODE_MASK                          \
 350                         << MAX77686_OPMODE_BUCK234_SHIFT,               \
 351 }
 352
 353 static struct regulator_desc regulators[] = {
 354         regulator_desc_ldo1_low(1),
 355         regulator_desc_ldo_low(2),
 356         regulator_desc_ldo(3),
 357         regulator_desc_ldo(4),
 358         regulator_desc_ldo(5),
 359         regulator_desc_ldo_low(6),
 360         regulator_desc_ldo_low(7),
 361         regulator_desc_ldo_low(8),
 362         regulator_desc_ldo(9),
 363         regulator_desc_lpm_ldo(10),
 364         regulator_desc_lpm_ldo(11),
 365         regulator_desc_lpm_ldo(12),
 366         regulator_desc_ldo(13),
 367         regulator_desc_lpm_ldo(14),
 368         regulator_desc_ldo_low(15),
 369         regulator_desc_lpm_ldo(16),
 370         regulator_desc_ldo(17),
 371         regulator_desc_ldo(18),
 372         regulator_desc_ldo(19),
 373         regulator_desc_ldo(20),
 374         regulator_desc_ldo(21),
 375         regulator_desc_ldo(22),
 376         regulator_desc_ldo(23),
 377         regulator_desc_ldo(24),
 378         regulator_desc_ldo(25),
 379         regulator_desc_ldo(26),
 380         regulator_desc_buck1(1),
 381         regulator_desc_buck_dvs(2),
 382         regulator_desc_buck_dvs(3),
 383         regulator_desc_buck_dvs(4),
 384         regulator_desc_buck(5),
 385         regulator_desc_buck(6),
 386         regulator_desc_buck(7),
 387         regulator_desc_buck(8),
 388         regulator_desc_buck(9),
 389 };
 390
 391 #ifdef CONFIG_OF
 392 static int max77686_pmic_dt_parse_pdata(struct platform_device *pdev,
 393                                         struct max77686_platform_data *pdata)
 394 {
 395         struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 396         struct device_node *pmic_np, *regulators_np;
 397         struct max77686_regulator_data *rdata;
 398         struct of_regulator_match rmatch;
 399         unsigned int i;
 400
 401         pmic_np = iodev->dev->of_node;
 402         regulators_np = of_get_child_by_name(pmic_np, "voltage-regulators");
 403         if (!regulators_np) {
 404                 dev_err(&pdev->dev, "could not find regulators sub-node\n");
 405                 return -EINVAL;
 406         }
 407
 408         pdata->num_regulators = ARRAY_SIZE(regulators);
 409         rdata = devm_kzalloc(&pdev->dev, sizeof(*rdata) *
 410                              pdata->num_regulators, GFP_KERNEL);
 411         if (!rdata) {
 412                 of_node_put(regulators_np);
 413                 return -ENOMEM;
 414         }
 415
 416         for (i = 0; i < pdata->num_regulators; i++) {
 417                 rmatch.name = regulators[i].name;
 418                 rmatch.init_data = NULL;
 419                 rmatch.of_node = NULL;
 420                 of_regulator_match(&pdev->dev, regulators_np, &rmatch, 1);
 421                 rdata[i].initdata = rmatch.init_data;
 422                 rdata[i].of_node = rmatch.of_node;
 423         }
 424
 425         pdata->regulators = rdata;
 426         of_node_put(regulators_np);
 427
 428         return 0;
 429 }
 430 #else
 431 static int max77686_pmic_dt_parse_pdata(struct platform_device *pdev,
 432                                         struct max77686_platform_data *pdata)
 433 {
 434         return 0;
 435 }
 436 #endif /* CONFIG_OF */
 437
 438 static int max77686_pmic_probe(struct platform_device *pdev)
 439 {
 440         struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 441         struct max77686_platform_data *pdata = dev_get_platdata(iodev->dev);
 442         struct max77686_data *max77686;
 443         int i, ret = 0;
 444         struct regulator_config config = { };
 445
 446         dev_dbg(&pdev->dev, "%s\n", __func__);
 447
 448         if (!pdata) {
 449                 dev_err(&pdev->dev, "no platform data found for regulator\n");
 450                 return -ENODEV;
 451         }
 452
 453         if (iodev->dev->of_node) {
 454                 ret = max77686_pmic_dt_parse_pdata(pdev, pdata);
 455                 if (ret)
 456                         return ret;
 457         }
 458
 459         if (pdata->num_regulators != MAX77686_REGULATORS) {
 460                 dev_err(&pdev->dev,
 461                         "Invalid initial data for regulator's initialiation\n");
 462                 return -EINVAL;
 463         }
 464
 465         max77686 = devm_kzalloc(&pdev->dev, sizeof(struct max77686_data),
 466                                 GFP_KERNEL);
 467         if (!max77686)
 468                 return -ENOMEM;
 469
 470         config.dev = &pdev->dev;
 471         config.regmap = iodev->regmap;
 472         config.driver_data = max77686;
 473         platform_set_drvdata(pdev, max77686);
 474
 475         for (i = 0; i < MAX77686_REGULATORS; i++) {
 476                 struct regulator_dev *rdev;
 477
 478                 config.init_data = pdata->regulators[i].initdata;
 479                 config.of_node = pdata->regulators[i].of_node;
 480
 481                 max77686->opmode[i] = regulators[i].enable_mask;
 482                 rdev = devm_regulator_register(&pdev->dev,
 483                                                 &regulators[i], &config);
 484                 if (IS_ERR(rdev)) {
 485                         dev_err(&pdev->dev,
 486                                 "regulator init failed for %d\n", i);
 487                         return PTR_ERR(rdev);
 488                 }
 489         }
 490
 491         return 0;
 492 }
 493
 494 static const struct platform_device_id max77686_pmic_id[] = {
 495         {"max77686-pmic", 0},
 496         { },
 497 };
 498 MODULE_DEVICE_TABLE(platform, max77686_pmic_id);
 499
 500 static struct platform_driver max77686_pmic_driver = {
 501         .driver = {
 502                 .name = "max77686-pmic",
 503                 .owner = THIS_MODULE,
 504         },
 505         .probe = max77686_pmic_probe,
 506         .id_table = max77686_pmic_id,
 507 };
 508
 509 static int __init max77686_pmic_init(void)
 510 {
 511         return platform_driver_register(&max77686_pmic_driver);
 512 }
 513 subsys_initcall(max77686_pmic_init);
 514
 515 static void __exit max77686_pmic_cleanup(void)
 516 {
 517         platform_driver_unregister(&max77686_pmic_driver);
 518 }
 519 module_exit(max77686_pmic_cleanup);
 520
 521 MODULE_DESCRIPTION("MAXIM 77686 Regulator Driver");
 522 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
 523 MODULE_LICENSE("GPL");