drivers/mfd/ab8500-gpadc.c

   1 /*
   2  * Copyright (C) ST-Ericsson SA 2010
   3  *
   4  * License Terms: GNU General Public License v2
   5  * Author: Arun R Murthy <arun.murthy@stericsson.com>
   6  * Author: Daniel Willerud <daniel.willerud@stericsson.com>
   7  * Author: Johan Palsson <johan.palsson@stericsson.com>
   8  */
   9 #include <linux/init.h>
  10 #include <linux/module.h>
  11 #include <linux/device.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/delay.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/completion.h>
  17 #include <linux/regulator/consumer.h>
  18 #include <linux/err.h>
  19 #include <linux/slab.h>
  20 #include <linux/list.h>
  21 #include <linux/mfd/ab8500.h>
  22 #include <linux/mfd/abx500.h>
  23 #include <linux/mfd/ab8500/gpadc.h>
  24
  25 /*
  26  * GPADC register offsets
  27  * Bank : 0x0A
  28  */
  29 #define AB8500_GPADC_CTRL1_REG          0x00
  30 #define AB8500_GPADC_CTRL2_REG          0x01
  31 #define AB8500_GPADC_CTRL3_REG          0x02
  32 #define AB8500_GPADC_AUTO_TIMER_REG     0x03
  33 #define AB8500_GPADC_STAT_REG           0x04
  34 #define AB8500_GPADC_MANDATAL_REG       0x05
  35 #define AB8500_GPADC_MANDATAH_REG       0x06
  36 #define AB8500_GPADC_AUTODATAL_REG      0x07
  37 #define AB8500_GPADC_AUTODATAH_REG      0x08
  38 #define AB8500_GPADC_MUX_CTRL_REG       0x09
  39
  40 /*
  41  * OTP register offsets
  42  * Bank : 0x15
  43  */
  44 #define AB8500_GPADC_CAL_1              0x0F
  45 #define AB8500_GPADC_CAL_2              0x10
  46 #define AB8500_GPADC_CAL_3              0x11
  47 #define AB8500_GPADC_CAL_4              0x12
  48 #define AB8500_GPADC_CAL_5              0x13
  49 #define AB8500_GPADC_CAL_6              0x14
  50 #define AB8500_GPADC_CAL_7              0x15
  51
  52 /* gpadc constants */
  53 #define EN_VINTCORE12                   0x04
  54 #define EN_VTVOUT                       0x02
  55 #define EN_GPADC                        0x01
  56 #define DIS_GPADC                       0x00
  57 #define SW_AVG_16                       0x60
  58 #define ADC_SW_CONV                     0x04
  59 #define EN_ICHAR                        0x80
  60 #define EN_BUF                          0x40
  61 #define DIS_ZERO                        0x00
  62 #define GPADC_BUSY                      0x01
  63
  64 /* GPADC constants from AB8500 spec, UM0836 */
  65 #define ADC_RESOLUTION                  1024
  66 #define ADC_CH_BTEMP_MIN                0
  67 #define ADC_CH_BTEMP_MAX                1350
  68 #define ADC_CH_DIETEMP_MIN              0
  69 #define ADC_CH_DIETEMP_MAX              1350
  70 #define ADC_CH_CHG_V_MIN                0
  71 #define ADC_CH_CHG_V_MAX                20030
  72 #define ADC_CH_ACCDET2_MIN              0
  73 #define ADC_CH_ACCDET2_MAX              2500
  74 #define ADC_CH_VBAT_MIN                 2300
  75 #define ADC_CH_VBAT_MAX                 4800
  76 #define ADC_CH_CHG_I_MIN                0
  77 #define ADC_CH_CHG_I_MAX                1500
  78 #define ADC_CH_BKBAT_MIN                0
  79 #define ADC_CH_BKBAT_MAX                3200
  80
  81 /* This is used to not lose precision when dividing to get gain and offset */
  82 #define CALIB_SCALE                     1000
  83
  84 enum cal_channels {
  85         ADC_INPUT_VMAIN = 0,
  86         ADC_INPUT_BTEMP,
  87         ADC_INPUT_VBAT,
  88         NBR_CAL_INPUTS,
  89 };
  90
  91 /**
  92  * struct adc_cal_data - Table for storing gain and offset for the calibrated
  93  * ADC channels
  94  * @gain:               Gain of the ADC channel
  95  * @offset:             Offset of the ADC channel
  96  */
  97 struct adc_cal_data {
  98         u64 gain;
  99         u64 offset;
 100 };
 101
 102 /**
 103  * struct ab8500_gpadc - AB8500 GPADC device information
 104  * @dev:                        pointer to the struct device
 105  * @node:                       a list of AB8500 GPADCs, hence prepared for
 106                                 reentrance
 107  * @ab8500_gpadc_complete:      pointer to the struct completion, to indicate
 108  *                              the completion of gpadc conversion
 109  * @ab8500_gpadc_lock:          structure of type mutex
 110  * @regu:                       pointer to the struct regulator
 111  * @irq:                        interrupt number that is used by gpadc
 112  * @cal_data                    array of ADC calibration data structs
 113  */
 114 struct ab8500_gpadc {
 115         struct device *dev;
 116         struct list_head node;
 117         struct completion ab8500_gpadc_complete;
 118         struct mutex ab8500_gpadc_lock;
 119         struct regulator *regu;
 120         int irq;
 121         struct adc_cal_data cal_data[NBR_CAL_INPUTS];
 122 };
 123
 124 static LIST_HEAD(ab8500_gpadc_list);
 125
 126 /**
 127  * ab8500_gpadc_get() - returns a reference to the primary AB8500 GPADC
 128  * (i.e. the first GPADC in the instance list)
 129  */
 130 struct ab8500_gpadc *ab8500_gpadc_get(char *name)
 131 {
 132         struct ab8500_gpadc *gpadc;
 133
 134         list_for_each_entry(gpadc, &ab8500_gpadc_list, node) {
 135                 if (!strcmp(name, dev_name(gpadc->dev)))
 136                     return gpadc;
 137         }
 138
 139         return ERR_PTR(-ENOENT);
 140 }
 141 EXPORT_SYMBOL(ab8500_gpadc_get);
 142
 143 static int ab8500_gpadc_ad_to_voltage(struct ab8500_gpadc *gpadc, u8 input,
 144         int ad_value)
 145 {
 146         int res;
 147
 148         switch (input) {
 149         case MAIN_CHARGER_V:
 150                 /* For some reason we don't have calibrated data */
 151                 if (!gpadc->cal_data[ADC_INPUT_VMAIN].gain) {
 152                         res = ADC_CH_CHG_V_MIN + (ADC_CH_CHG_V_MAX -
 153                                 ADC_CH_CHG_V_MIN) * ad_value /
 154                                 ADC_RESOLUTION;
 155                         break;
 156                 }
 157                 /* Here we can use the calibrated data */
 158                 res = (int) (ad_value * gpadc->cal_data[ADC_INPUT_VMAIN].gain +
 159                         gpadc->cal_data[ADC_INPUT_VMAIN].offset) / CALIB_SCALE;
 160                 break;
 161
 162         case BAT_CTRL:
 163         case BTEMP_BALL:
 164         case ACC_DETECT1:
 165         case ADC_AUX1:
 166         case ADC_AUX2:
 167                 /* For some reason we don't have calibrated data */
 168                 if (!gpadc->cal_data[ADC_INPUT_BTEMP].gain) {
 169                         res = ADC_CH_BTEMP_MIN + (ADC_CH_BTEMP_MAX -
 170                                 ADC_CH_BTEMP_MIN) * ad_value /
 171                                 ADC_RESOLUTION;
 172                         break;
 173                 }
 174                 /* Here we can use the calibrated data */
 175                 res = (int) (ad_value * gpadc->cal_data[ADC_INPUT_BTEMP].gain +
 176                         gpadc->cal_data[ADC_INPUT_BTEMP].offset) / CALIB_SCALE;
 177                 break;
 178
 179         case MAIN_BAT_V:
 180                 /* For some reason we don't have calibrated data */
 181                 if (!gpadc->cal_data[ADC_INPUT_VBAT].gain) {
 182                         res = ADC_CH_VBAT_MIN + (ADC_CH_VBAT_MAX -
 183                                 ADC_CH_VBAT_MIN) * ad_value /
 184                                 ADC_RESOLUTION;
 185                         break;
 186                 }
 187                 /* Here we can use the calibrated data */
 188                 res = (int) (ad_value * gpadc->cal_data[ADC_INPUT_VBAT].gain +
 189                         gpadc->cal_data[ADC_INPUT_VBAT].offset) / CALIB_SCALE;
 190                 break;
 191
 192         case DIE_TEMP:
 193                 res = ADC_CH_DIETEMP_MIN +
 194                         (ADC_CH_DIETEMP_MAX - ADC_CH_DIETEMP_MIN) * ad_value /
 195                         ADC_RESOLUTION;
 196                 break;
 197
 198         case ACC_DETECT2:
 199                 res = ADC_CH_ACCDET2_MIN +
 200                         (ADC_CH_ACCDET2_MAX - ADC_CH_ACCDET2_MIN) * ad_value /
 201                         ADC_RESOLUTION;
 202                 break;
 203
 204         case VBUS_V:
 205                 res = ADC_CH_CHG_V_MIN +
 206                         (ADC_CH_CHG_V_MAX - ADC_CH_CHG_V_MIN) * ad_value /
 207                         ADC_RESOLUTION;
 208                 break;
 209
 210         case MAIN_CHARGER_C:
 211         case USB_CHARGER_C:
 212                 res = ADC_CH_CHG_I_MIN +
 213                         (ADC_CH_CHG_I_MAX - ADC_CH_CHG_I_MIN) * ad_value /
 214                         ADC_RESOLUTION;
 215                 break;
 216
 217         case BK_BAT_V:
 218                 res = ADC_CH_BKBAT_MIN +
 219                         (ADC_CH_BKBAT_MAX - ADC_CH_BKBAT_MIN) * ad_value /
 220                         ADC_RESOLUTION;
 221                 break;
 222
 223         default:
 224                 dev_err(gpadc->dev,
 225                         "unknown channel, not possible to convert\n");
 226                 res = -EINVAL;
 227                 break;
 228
 229         }
 230         return res;
 231 }
 232
 233 /**
 234  * ab8500_gpadc_convert() - gpadc conversion
 235  * @input:      analog input to be converted to digital data
 236  *
 237  * This function converts the selected analog i/p to digital
 238  * data.
 239  */
 240 int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 input)
 241 {
 242         int ret;
 243         u16 data = 0;
 244         int looplimit = 0;
 245         u8 val, low_data, high_data;
 246
 247         if (!gpadc)
 248                 return -ENODEV;
 249
 250         mutex_lock(&gpadc->ab8500_gpadc_lock);
 251         /* Enable VTVout LDO this is required for GPADC */
 252         regulator_enable(gpadc->regu);
 253
 254         /* Check if ADC is not busy, lock and proceed */
 255         do {
 256                 ret = abx500_get_register_interruptible(gpadc->dev,
 257                         AB8500_GPADC, AB8500_GPADC_STAT_REG, &val);
 258                 if (ret < 0)
 259                         goto out;
 260                 if (!(val & GPADC_BUSY))
 261                         break;
 262                 msleep(10);
 263         } while (++looplimit < 10);
 264         if (looplimit >= 10 && (val & GPADC_BUSY)) {
 265                 dev_err(gpadc->dev, "gpadc_conversion: GPADC busy");
 266                 ret = -EINVAL;
 267                 goto out;
 268         }
 269
 270         /* Enable GPADC */
 271         ret = abx500_mask_and_set_register_interruptible(gpadc->dev,
 272                 AB8500_GPADC, AB8500_GPADC_CTRL1_REG, EN_GPADC, EN_GPADC);
 273         if (ret < 0) {
 274                 dev_err(gpadc->dev, "gpadc_conversion: enable gpadc failed\n");
 275                 goto out;
 276         }
 277         /* Select the input source and set average samples to 16 */
 278         ret = abx500_set_register_interruptible(gpadc->dev, AB8500_GPADC,
 279                 AB8500_GPADC_CTRL2_REG, (input | SW_AVG_16));
 280         if (ret < 0) {
 281                 dev_err(gpadc->dev,
 282                         "gpadc_conversion: set avg samples failed\n");
 283                 goto out;
 284         }
 285         /*
 286          * Enable ADC, buffering, select rising edge and enable ADC path
 287          * charging current sense if it needed
 288          */
 289         switch (input) {
 290         case MAIN_CHARGER_C:
 291         case USB_CHARGER_C:
 292                 ret = abx500_mask_and_set_register_interruptible(gpadc->dev,
 293                         AB8500_GPADC, AB8500_GPADC_CTRL1_REG,
 294                         EN_BUF | EN_ICHAR,
 295                         EN_BUF | EN_ICHAR);
 296                 break;
 297         default:
 298                 ret = abx500_mask_and_set_register_interruptible(gpadc->dev,
 299                         AB8500_GPADC, AB8500_GPADC_CTRL1_REG, EN_BUF, EN_BUF);
 300                 break;
 301         }
 302         if (ret < 0) {
 303                 dev_err(gpadc->dev,
 304                         "gpadc_conversion: select falling edge failed\n");
 305                 goto out;
 306         }
 307         ret = abx500_mask_and_set_register_interruptible(gpadc->dev,
 308                 AB8500_GPADC, AB8500_GPADC_CTRL1_REG, ADC_SW_CONV, ADC_SW_CONV);
 309         if (ret < 0) {
 310                 dev_err(gpadc->dev,
 311                         "gpadc_conversion: start s/w conversion failed\n");
 312                 goto out;
 313         }
 314         /* wait for completion of conversion */
 315         if (!wait_for_completion_timeout(&gpadc->ab8500_gpadc_complete, 2*HZ)) {
 316                 dev_err(gpadc->dev,
 317                         "timeout: didn't receive GPADC conversion interrupt\n");
 318                 ret = -EINVAL;
 319                 goto out;
 320         }
 321
 322         /* Read the converted RAW data */
 323         ret = abx500_get_register_interruptible(gpadc->dev, AB8500_GPADC,
 324                 AB8500_GPADC_MANDATAL_REG, &low_data);
 325         if (ret < 0) {
 326                 dev_err(gpadc->dev, "gpadc_conversion: read low data failed\n");
 327                 goto out;
 328         }
 329
 330         ret = abx500_get_register_interruptible(gpadc->dev, AB8500_GPADC,
 331                 AB8500_GPADC_MANDATAH_REG, &high_data);
 332         if (ret < 0) {
 333                 dev_err(gpadc->dev,
 334                         "gpadc_conversion: read high data failed\n");
 335                 goto out;
 336         }
 337
 338         data = (high_data << 8) | low_data;
 339         /* Disable GPADC */
 340         ret = abx500_set_register_interruptible(gpadc->dev, AB8500_GPADC,
 341                 AB8500_GPADC_CTRL1_REG, DIS_GPADC);
 342         if (ret < 0) {
 343                 dev_err(gpadc->dev, "gpadc_conversion: disable gpadc failed\n");
 344                 goto out;
 345         }
 346         /* Disable VTVout LDO this is required for GPADC */
 347         regulator_disable(gpadc->regu);
 348         mutex_unlock(&gpadc->ab8500_gpadc_lock);
 349         ret = ab8500_gpadc_ad_to_voltage(gpadc, input, data);
 350         return ret;
 351
 352 out:
 353         /*
 354          * It has shown to be needed to turn off the GPADC if an error occurs,
 355          * otherwise we might have problem when waiting for the busy bit in the
 356          * GPADC status register to go low. In V1.1 there wait_for_completion
 357          * seems to timeout when waiting for an interrupt.. Not seen in V2.0
 358          */
 359         (void) abx500_set_register_interruptible(gpadc->dev, AB8500_GPADC,
 360                 AB8500_GPADC_CTRL1_REG, DIS_GPADC);
 361         regulator_disable(gpadc->regu);
 362         mutex_unlock(&gpadc->ab8500_gpadc_lock);
 363         dev_err(gpadc->dev,
 364                 "gpadc_conversion: Failed to AD convert channel %d\n", input);
 365         return ret;
 366 }
 367 EXPORT_SYMBOL(ab8500_gpadc_convert);
 368
 369 /**
 370  * ab8500_bm_gpswadcconvend_handler() - isr for s/w gpadc conversion completion
 371  * @irq:        irq number
 372  * @data:       pointer to the data passed during request irq
 373  *
 374  * This is a interrupt service routine for s/w gpadc conversion completion.
 375  * Notifies the gpadc completion is completed and the converted raw value
 376  * can be read from the registers.
 377  * Returns IRQ status(IRQ_HANDLED)
 378  */
 379 static irqreturn_t ab8500_bm_gpswadcconvend_handler(int irq, void *_gpadc)
 380 {
 381         struct ab8500_gpadc *gpadc = _gpadc;
 382
 383         complete(&gpadc->ab8500_gpadc_complete);
 384
 385         return IRQ_HANDLED;
 386 }
 387
 388 static int otp_cal_regs[] = {
 389         AB8500_GPADC_CAL_1,
 390         AB8500_GPADC_CAL_2,
 391         AB8500_GPADC_CAL_3,
 392         AB8500_GPADC_CAL_4,
 393         AB8500_GPADC_CAL_5,
 394         AB8500_GPADC_CAL_6,
 395         AB8500_GPADC_CAL_7,
 396 };
 397
 398 static void ab8500_gpadc_read_calibration_data(struct ab8500_gpadc *gpadc)
 399 {
 400         int i;
 401         int ret[ARRAY_SIZE(otp_cal_regs)];
 402         u8 gpadc_cal[ARRAY_SIZE(otp_cal_regs)];
 403
 404         int vmain_high, vmain_low;
 405         int btemp_high, btemp_low;
 406         int vbat_high, vbat_low;
 407
 408         /* First we read all OTP registers and store the error code */
 409         for (i = 0; i < ARRAY_SIZE(otp_cal_regs); i++) {
 410                 ret[i] = abx500_get_register_interruptible(gpadc->dev,
 411                         AB8500_OTP_EMUL, otp_cal_regs[i],  &gpadc_cal[i]);
 412                 if (ret[i] < 0)
 413                         dev_err(gpadc->dev, "%s: read otp reg 0x%02x failed\n",
 414                                 __func__, otp_cal_regs[i]);
 415         }
 416
 417         /*
 418          * The ADC calibration data is stored in OTP registers.
 419          * The layout of the calibration data is outlined below and a more
 420          * detailed description can be found in UM0836
 421          *
 422          * vm_h/l = vmain_high/low
 423          * bt_h/l = btemp_high/low
 424          * vb_h/l = vbat_high/low
 425          *
 426          * Data bits:
 427          * | 7     | 6     | 5     | 4     | 3     | 2     | 1     | 0
 428          * |.......|.......|.......|.......|.......|.......|.......|.......
 429          * |                                               | vm_h9 | vm_h8
 430          * |.......|.......|.......|.......|.......|.......|.......|.......
 431          * |               | vm_h7 | vm_h6 | vm_h5 | vm_h4 | vm_h3 | vm_h2
 432          * |.......|.......|.......|.......|.......|.......|.......|.......
 433          * | vm_h1 | vm_h0 | vm_l4 | vm_l3 | vm_l2 | vm_l1 | vm_l0 | bt_h9
 434          * |.......|.......|.......|.......|.......|.......|.......|.......
 435          * | bt_h8 | bt_h7 | bt_h6 | bt_h5 | bt_h4 | bt_h3 | bt_h2 | bt_h1
 436          * |.......|.......|.......|.......|.......|.......|.......|.......
 437          * | bt_h0 | bt_l4 | bt_l3 | bt_l2 | bt_l1 | bt_l0 | vb_h9 | vb_h8
 438          * |.......|.......|.......|.......|.......|.......|.......|.......
 439          * | vb_h7 | vb_h6 | vb_h5 | vb_h4 | vb_h3 | vb_h2 | vb_h1 | vb_h0
 440          * |.......|.......|.......|.......|.......|.......|.......|.......
 441          * | vb_l5 | vb_l4 | vb_l3 | vb_l2 | vb_l1 | vb_l0 |
 442          * |.......|.......|.......|.......|.......|.......|.......|.......
 443          *
 444          *
 445          * Ideal output ADC codes corresponding to injected input voltages
 446          * during manufacturing is:
 447          *
 448          * vmain_high: Vin = 19500mV / ADC ideal code = 997
 449          * vmain_low:  Vin = 315mV   / ADC ideal code = 16
 450          * btemp_high: Vin = 1300mV  / ADC ideal code = 985
 451          * btemp_low:  Vin = 21mV    / ADC ideal code = 16
 452          * vbat_high:  Vin = 4700mV  / ADC ideal code = 982
 453          * vbat_low:   Vin = 2380mV  / ADC ideal code = 33
 454          */
 455
 456         /* Calculate gain and offset for VMAIN if all reads succeeded */
 457         if (!(ret[0] < 0 || ret[1] < 0 || ret[2] < 0)) {
 458                 vmain_high = (((gpadc_cal[0] & 0x03) << 8) |
 459                         ((gpadc_cal[1] & 0x3F) << 2) |
 460                         ((gpadc_cal[2] & 0xC0) >> 6));
 461
 462                 vmain_low = ((gpadc_cal[2] & 0x3E) >> 1);
 463
 464                 gpadc->cal_data[ADC_INPUT_VMAIN].gain = CALIB_SCALE *
 465                         (19500 - 315) / (vmain_high - vmain_low);
 466
 467                 gpadc->cal_data[ADC_INPUT_VMAIN].offset = CALIB_SCALE * 19500 -
 468                         (CALIB_SCALE * (19500 - 315) /
 469                          (vmain_high - vmain_low)) * vmain_high;
 470         } else {
 471                 gpadc->cal_data[ADC_INPUT_VMAIN].gain = 0;
 472         }
 473
 474         /* Calculate gain and offset for BTEMP if all reads succeeded */
 475         if (!(ret[2] < 0 || ret[3] < 0 || ret[4] < 0)) {
 476                 btemp_high = (((gpadc_cal[2] & 0x01) << 9) |
 477                         (gpadc_cal[3] << 1) |
 478                         ((gpadc_cal[4] & 0x80) >> 7));
 479
 480                 btemp_low = ((gpadc_cal[4] & 0x7C) >> 2);
 481
 482                 gpadc->cal_data[ADC_INPUT_BTEMP].gain =
 483                         CALIB_SCALE * (1300 - 21) / (btemp_high - btemp_low);
 484
 485                 gpadc->cal_data[ADC_INPUT_BTEMP].offset = CALIB_SCALE * 1300 -
 486                         (CALIB_SCALE * (1300 - 21) /
 487                         (btemp_high - btemp_low)) * btemp_high;
 488         } else {
 489                 gpadc->cal_data[ADC_INPUT_BTEMP].gain = 0;
 490         }
 491
 492         /* Calculate gain and offset for VBAT if all reads succeeded */
 493         if (!(ret[4] < 0 || ret[5] < 0 || ret[6] < 0)) {
 494                 vbat_high = (((gpadc_cal[4] & 0x03) << 8) | gpadc_cal[5]);
 495                 vbat_low = ((gpadc_cal[6] & 0xFC) >> 2);
 496
 497                 gpadc->cal_data[ADC_INPUT_VBAT].gain = CALIB_SCALE *
 498                         (4700 - 2380) / (vbat_high - vbat_low);
 499
 500                 gpadc->cal_data[ADC_INPUT_VBAT].offset = CALIB_SCALE * 4700 -
 501                         (CALIB_SCALE * (4700 - 2380) /
 502                         (vbat_high - vbat_low)) * vbat_high;
 503         } else {
 504                 gpadc->cal_data[ADC_INPUT_VBAT].gain = 0;
 505         }
 506
 507         dev_dbg(gpadc->dev, "VMAIN gain %llu offset %llu\n",
 508                 gpadc->cal_data[ADC_INPUT_VMAIN].gain,
 509                 gpadc->cal_data[ADC_INPUT_VMAIN].offset);
 510
 511         dev_dbg(gpadc->dev, "BTEMP gain %llu offset %llu\n",
 512                 gpadc->cal_data[ADC_INPUT_BTEMP].gain,
 513                 gpadc->cal_data[ADC_INPUT_BTEMP].offset);
 514
 515         dev_dbg(gpadc->dev, "VBAT gain %llu offset %llu\n",
 516                 gpadc->cal_data[ADC_INPUT_VBAT].gain,
 517                 gpadc->cal_data[ADC_INPUT_VBAT].offset);
 518 }
 519
 520 static int __devinit ab8500_gpadc_probe(struct platform_device *pdev)
 521 {
 522         int ret = 0;
 523         struct ab8500_gpadc *gpadc;
 524
 525         gpadc = kzalloc(sizeof(struct ab8500_gpadc), GFP_KERNEL);
 526         if (!gpadc) {
 527                 dev_err(&pdev->dev, "Error: No memory\n");
 528                 return -ENOMEM;
 529         }
 530
 531         gpadc->irq = platform_get_irq_byname(pdev, "SW_CONV_END");
 532         if (gpadc->irq < 0) {
 533                 dev_err(gpadc->dev, "failed to get platform irq-%d\n",
 534                         gpadc->irq);
 535                 ret = gpadc->irq;
 536                 goto fail;
 537         }
 538
 539         gpadc->dev = &pdev->dev;
 540         mutex_init(&gpadc->ab8500_gpadc_lock);
 541
 542         /* Initialize completion used to notify completion of conversion */
 543         init_completion(&gpadc->ab8500_gpadc_complete);
 544
 545         /* Register interrupt  - SwAdcComplete */
 546         ret = request_threaded_irq(gpadc->irq, NULL,
 547                 ab8500_bm_gpswadcconvend_handler,
 548                 IRQF_NO_SUSPEND | IRQF_SHARED, "ab8500-gpadc", gpadc);
 549         if (ret < 0) {
 550                 dev_err(gpadc->dev, "Failed to register interrupt, irq: %d\n",
 551                         gpadc->irq);
 552                 goto fail;
 553         }
 554
 555         /* VTVout LDO used to power up ab8500-GPADC */
 556         gpadc->regu = regulator_get(&pdev->dev, "vddadc");
 557         if (IS_ERR(gpadc->regu)) {
 558                 ret = PTR_ERR(gpadc->regu);
 559                 dev_err(gpadc->dev, "failed to get vtvout LDO\n");
 560                 goto fail_irq;
 561         }
 562         ab8500_gpadc_read_calibration_data(gpadc);
 563         list_add_tail(&gpadc->node, &ab8500_gpadc_list);
 564         dev_dbg(gpadc->dev, "probe success\n");
 565         return 0;
 566 fail_irq:
 567         free_irq(gpadc->irq, gpadc);
 568 fail:
 569         kfree(gpadc);
 570         gpadc = NULL;
 571         return ret;
 572 }
 573
 574 static int __devexit ab8500_gpadc_remove(struct platform_device *pdev)
 575 {
 576         struct ab8500_gpadc *gpadc = platform_get_drvdata(pdev);
 577
 578         /* remove this gpadc entry from the list */
 579         list_del(&gpadc->node);
 580         /* remove interrupt  - completion of Sw ADC conversion */
 581         free_irq(gpadc->irq, gpadc);
 582         /* disable VTVout LDO that is being used by GPADC */
 583         regulator_put(gpadc->regu);
 584         kfree(gpadc);
 585         gpadc = NULL;
 586         return 0;
 587 }
 588
 589 static struct platform_driver ab8500_gpadc_driver = {
 590         .probe = ab8500_gpadc_probe,
 591         .remove = __devexit_p(ab8500_gpadc_remove),
 592         .driver = {
 593                 .name = "ab8500-gpadc",
 594                 .owner = THIS_MODULE,
 595         },
 596 };
 597
 598 static int __init ab8500_gpadc_init(void)
 599 {
 600         return platform_driver_register(&ab8500_gpadc_driver);
 601 }
 602
 603 static void __exit ab8500_gpadc_exit(void)
 604 {
 605         platform_driver_unregister(&ab8500_gpadc_driver);
 606 }
 607
 608 subsys_initcall_sync(ab8500_gpadc_init);
 609 module_exit(ab8500_gpadc_exit);
 610
 611 MODULE_LICENSE("GPL v2");
 612 MODULE_AUTHOR("Arun R Murthy, Daniel Willerud, Johan Palsson");
 613 MODULE_ALIAS("platform:ab8500_gpadc");
 614 MODULE_DESCRIPTION("AB8500 GPADC driver");