drivers/iio/adc/cpcap-adc.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2017 Tony Lindgren <tony@atomide.com>
   4  *
   5  * Rewritten for Linux IIO framework with some code based on
   6  * earlier driver found in the Motorola Linux kernel:
   7  *
   8  * Copyright (C) 2009-2010 Motorola, Inc.
   9  */
  10
  11 #include <linux/delay.h>
  12 #include <linux/device.h>
  13 #include <linux/err.h>
  14 #include <linux/init.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/kernel.h>
  17 #include <linux/module.h>
  18 #include <linux/mod_devicetable.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/property.h>
  21 #include <linux/regmap.h>
  22
  23 #include <linux/iio/buffer.h>
  24 #include <linux/iio/driver.h>
  25 #include <linux/iio/iio.h>
  26 #include <linux/iio/kfifo_buf.h>
  27 #include <linux/mfd/motorola-cpcap.h>
  28
  29 /* Register CPCAP_REG_ADCC1 bits */
  30 #define CPCAP_BIT_ADEN_AUTO_CLR         BIT(15) /* Currently unused */
  31 #define CPCAP_BIT_CAL_MODE              BIT(14) /* Set with BIT_RAND0 */
  32 #define CPCAP_BIT_ADC_CLK_SEL1          BIT(13) /* Currently unused */
  33 #define CPCAP_BIT_ADC_CLK_SEL0          BIT(12) /* Currently unused */
  34 #define CPCAP_BIT_ATOX                  BIT(11)
  35 #define CPCAP_BIT_ATO3                  BIT(10)
  36 #define CPCAP_BIT_ATO2                  BIT(9)
  37 #define CPCAP_BIT_ATO1                  BIT(8)
  38 #define CPCAP_BIT_ATO0                  BIT(7)
  39 #define CPCAP_BIT_ADA2                  BIT(6)
  40 #define CPCAP_BIT_ADA1                  BIT(5)
  41 #define CPCAP_BIT_ADA0                  BIT(4)
  42 #define CPCAP_BIT_AD_SEL1               BIT(3)  /* Set for bank1 */
  43 #define CPCAP_BIT_RAND1                 BIT(2)  /* Set for channel 16 & 17 */
  44 #define CPCAP_BIT_RAND0                 BIT(1)  /* Set with CAL_MODE */
  45 #define CPCAP_BIT_ADEN                  BIT(0)  /* Currently unused */
  46
  47 #define CPCAP_REG_ADCC1_DEFAULTS        (CPCAP_BIT_ADEN_AUTO_CLR | \
  48                                          CPCAP_BIT_ADC_CLK_SEL0 |  \
  49                                          CPCAP_BIT_RAND1)
  50
  51 /* Register CPCAP_REG_ADCC2 bits */
  52 #define CPCAP_BIT_CAL_FACTOR_ENABLE     BIT(15) /* Currently unused */
  53 #define CPCAP_BIT_BATDETB_EN            BIT(14) /* Currently unused */
  54 #define CPCAP_BIT_ADTRIG_ONESHOT        BIT(13) /* Set for !TIMING_IMM */
  55 #define CPCAP_BIT_ASC                   BIT(12) /* Set for TIMING_IMM */
  56 #define CPCAP_BIT_ATOX_PS_FACTOR        BIT(11)
  57 #define CPCAP_BIT_ADC_PS_FACTOR1        BIT(10)
  58 #define CPCAP_BIT_ADC_PS_FACTOR0        BIT(9)
  59 #define CPCAP_BIT_AD4_SELECT            BIT(8)  /* Currently unused */
  60 #define CPCAP_BIT_ADC_BUSY              BIT(7)  /* Currently unused */
  61 #define CPCAP_BIT_THERMBIAS_EN          BIT(6)  /* Bias for AD0_BATTDETB */
  62 #define CPCAP_BIT_ADTRIG_DIS            BIT(5)  /* Disable interrupt */
  63 #define CPCAP_BIT_LIADC                 BIT(4)  /* Currently unused */
  64 #define CPCAP_BIT_TS_REFEN              BIT(3)  /* Currently unused */
  65 #define CPCAP_BIT_TS_M2                 BIT(2)  /* Currently unused */
  66 #define CPCAP_BIT_TS_M1                 BIT(1)  /* Currently unused */
  67 #define CPCAP_BIT_TS_M0                 BIT(0)  /* Currently unused */
  68
  69 #define CPCAP_REG_ADCC2_DEFAULTS        (CPCAP_BIT_AD4_SELECT | \
  70                                          CPCAP_BIT_ADTRIG_DIS | \
  71                                          CPCAP_BIT_LIADC | \
  72                                          CPCAP_BIT_TS_M2 | \
  73                                          CPCAP_BIT_TS_M1)
  74
  75 #define CPCAP_MAX_TEMP_LVL              27
  76 #define CPCAP_FOUR_POINT_TWO_ADC        801
  77 #define ST_ADC_CAL_CHRGI_HIGH_THRESHOLD 530
  78 #define ST_ADC_CAL_CHRGI_LOW_THRESHOLD  494
  79 #define ST_ADC_CAL_BATTI_HIGH_THRESHOLD 530
  80 #define ST_ADC_CAL_BATTI_LOW_THRESHOLD  494
  81 #define ST_ADC_CALIBRATE_DIFF_THRESHOLD 3
  82
  83 #define CPCAP_ADC_MAX_RETRIES           5       /* Calibration */
  84
  85 /*
  86  * struct cpcap_adc_ato - timing settings for cpcap adc
  87  *
  88  * Unfortunately no cpcap documentation available, please document when
  89  * using these.
  90  */
  91 struct cpcap_adc_ato {
  92         unsigned short ato_in;
  93         unsigned short atox_in;
  94         unsigned short adc_ps_factor_in;
  95         unsigned short atox_ps_factor_in;
  96         unsigned short ato_out;
  97         unsigned short atox_out;
  98         unsigned short adc_ps_factor_out;
  99         unsigned short atox_ps_factor_out;
 100 };
 101
 102 /**
 103  * struct cpcap-adc - cpcap adc device driver data
 104  * @reg: cpcap regmap
 105  * @dev: struct device
 106  * @vendor: cpcap vendor
 107  * @irq: interrupt
 108  * @lock: mutex
 109  * @ato: request timings
 110  * @wq_data_avail: work queue
 111  * @done: work done
 112  */
 113 struct cpcap_adc {
 114         struct regmap *reg;
 115         struct device *dev;
 116         u16 vendor;
 117         int irq;
 118         struct mutex lock;      /* ADC register access lock */
 119         const struct cpcap_adc_ato *ato;
 120         wait_queue_head_t wq_data_avail;
 121         bool done;
 122 };
 123
 124 /*
 125  * enum cpcap_adc_channel - cpcap adc channels
 126  */
 127 enum cpcap_adc_channel {
 128         /* Bank0 channels */
 129         CPCAP_ADC_AD0,          /* Battery temperature */
 130         CPCAP_ADC_BATTP,        /* Battery voltage */
 131         CPCAP_ADC_VBUS,         /* USB VBUS voltage */
 132         CPCAP_ADC_AD3,          /* Die temperature when charging */
 133         CPCAP_ADC_BPLUS_AD4,    /* Another battery or system voltage */
 134         CPCAP_ADC_CHG_ISENSE,   /* Calibrated charge current */
 135         CPCAP_ADC_BATTI,        /* Calibrated system current */
 136         CPCAP_ADC_USB_ID,       /* USB OTG ID, unused on droid 4? */
 137
 138         /* Bank1 channels */
 139         CPCAP_ADC_AD8,          /* Seems unused */
 140         CPCAP_ADC_AD9,          /* Seems unused */
 141         CPCAP_ADC_LICELL,       /* Maybe system voltage? Always 3V */
 142         CPCAP_ADC_HV_BATTP,     /* Another battery detection? */
 143         CPCAP_ADC_TSX1_AD12,    /* Seems unused, for touchscreen? */
 144         CPCAP_ADC_TSX2_AD13,    /* Seems unused, for touchscreen? */
 145         CPCAP_ADC_TSY1_AD14,    /* Seems unused, for touchscreen? */
 146         CPCAP_ADC_TSY2_AD15,    /* Seems unused, for touchscreen? */
 147
 148         /* Remuxed channels using bank0 entries */
 149         CPCAP_ADC_BATTP_PI16,   /* Alternative mux mode for BATTP */
 150         CPCAP_ADC_BATTI_PI17,   /* Alternative mux mode for BATTI */
 151
 152         CPCAP_ADC_CHANNEL_NUM,
 153 };
 154
 155 /*
 156  * enum cpcap_adc_timing - cpcap adc timing options
 157  *
 158  * CPCAP_ADC_TIMING_IMM seems to be immediate with no timings.
 159  * Please document when using.
 160  */
 161 enum cpcap_adc_timing {
 162         CPCAP_ADC_TIMING_IMM,
 163         CPCAP_ADC_TIMING_IN,
 164         CPCAP_ADC_TIMING_OUT,
 165 };
 166
 167 /**
 168  * struct cpcap_adc_phasing_tbl - cpcap phasing table
 169  * @offset: offset in the phasing table
 170  * @multiplier: multiplier in the phasing table
 171  * @divider: divider in the phasing table
 172  * @min: minimum value
 173  * @max: maximum value
 174  */
 175 struct cpcap_adc_phasing_tbl {
 176         short offset;
 177         unsigned short multiplier;
 178         unsigned short divider;
 179         short min;
 180         short max;
 181 };
 182
 183 /**
 184  * struct cpcap_adc_conversion_tbl - cpcap conversion table
 185  * @conv_type: conversion type
 186  * @align_offset: align offset
 187  * @conv_offset: conversion offset
 188  * @cal_offset: calibration offset
 189  * @multiplier: conversion multiplier
 190  * @divider: conversion divider
 191  */
 192 struct cpcap_adc_conversion_tbl {
 193         enum iio_chan_info_enum conv_type;
 194         int align_offset;
 195         int conv_offset;
 196         int cal_offset;
 197         int multiplier;
 198         int divider;
 199 };
 200
 201 /**
 202  * struct cpcap_adc_request - cpcap adc request
 203  * @channel: request channel
 204  * @phase_tbl: channel phasing table
 205  * @conv_tbl: channel conversion table
 206  * @bank_index: channel index within the bank
 207  * @timing: timing settings
 208  * @result: result
 209  */
 210 struct cpcap_adc_request {
 211         int channel;
 212         const struct cpcap_adc_phasing_tbl *phase_tbl;
 213         const struct cpcap_adc_conversion_tbl *conv_tbl;
 214         int bank_index;
 215         enum cpcap_adc_timing timing;
 216         int result;
 217 };
 218
 219 /* Phasing table for channels. Note that channels 16 & 17 use BATTP and BATTI */
 220 static const struct cpcap_adc_phasing_tbl bank_phasing[] = {
 221         /* Bank0 */
 222         [CPCAP_ADC_AD0] =          {0, 0x80, 0x80,    0, 1023},
 223         [CPCAP_ADC_BATTP] =        {0, 0x80, 0x80,    0, 1023},
 224         [CPCAP_ADC_VBUS] =         {0, 0x80, 0x80,    0, 1023},
 225         [CPCAP_ADC_AD3] =          {0, 0x80, 0x80,    0, 1023},
 226         [CPCAP_ADC_BPLUS_AD4] =    {0, 0x80, 0x80,    0, 1023},
 227         [CPCAP_ADC_CHG_ISENSE] =   {0, 0x80, 0x80, -512,  511},
 228         [CPCAP_ADC_BATTI] =        {0, 0x80, 0x80, -512,  511},
 229         [CPCAP_ADC_USB_ID] =       {0, 0x80, 0x80,    0, 1023},
 230
 231         /* Bank1 */
 232         [CPCAP_ADC_AD8] =          {0, 0x80, 0x80,    0, 1023},
 233         [CPCAP_ADC_AD9] =          {0, 0x80, 0x80,    0, 1023},
 234         [CPCAP_ADC_LICELL] =       {0, 0x80, 0x80,    0, 1023},
 235         [CPCAP_ADC_HV_BATTP] =     {0, 0x80, 0x80,    0, 1023},
 236         [CPCAP_ADC_TSX1_AD12] =    {0, 0x80, 0x80,    0, 1023},
 237         [CPCAP_ADC_TSX2_AD13] =    {0, 0x80, 0x80,    0, 1023},
 238         [CPCAP_ADC_TSY1_AD14] =    {0, 0x80, 0x80,    0, 1023},
 239         [CPCAP_ADC_TSY2_AD15] =    {0, 0x80, 0x80,    0, 1023},
 240 };
 241
 242 /*
 243  * Conversion table for channels. Updated during init based on calibration.
 244  * Here too channels 16 & 17 use BATTP and BATTI.
 245  */
 246 static struct cpcap_adc_conversion_tbl bank_conversion[] = {
 247         /* Bank0 */
 248         [CPCAP_ADC_AD0] = {
 249                 IIO_CHAN_INFO_PROCESSED,    0,    0, 0,     1,    1,
 250         },
 251         [CPCAP_ADC_BATTP] = {
 252                 IIO_CHAN_INFO_PROCESSED,    0, 2400, 0,  2300, 1023,
 253         },
 254         [CPCAP_ADC_VBUS] = {
 255                 IIO_CHAN_INFO_PROCESSED,    0,    0, 0, 10000, 1023,
 256         },
 257         [CPCAP_ADC_AD3] = {
 258                 IIO_CHAN_INFO_PROCESSED,    0,    0, 0,     1,    1,
 259                 },
 260         [CPCAP_ADC_BPLUS_AD4] = {
 261                 IIO_CHAN_INFO_PROCESSED,    0, 2400, 0,  2300, 1023,
 262         },
 263         [CPCAP_ADC_CHG_ISENSE] = {
 264                 IIO_CHAN_INFO_PROCESSED, -512,    2, 0,  5000, 1023,
 265         },
 266         [CPCAP_ADC_BATTI] = {
 267                 IIO_CHAN_INFO_PROCESSED, -512,    2, 0,  5000, 1023,
 268         },
 269         [CPCAP_ADC_USB_ID] = {
 270                 IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
 271         },
 272
 273         /* Bank1 */
 274         [CPCAP_ADC_AD8] = {
 275                 IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
 276         },
 277         [CPCAP_ADC_AD9] = {
 278                 IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
 279         },
 280         [CPCAP_ADC_LICELL] = {
 281                 IIO_CHAN_INFO_PROCESSED,    0,    0, 0,  3400, 1023,
 282         },
 283         [CPCAP_ADC_HV_BATTP] = {
 284                 IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
 285         },
 286         [CPCAP_ADC_TSX1_AD12] = {
 287                 IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
 288         },
 289         [CPCAP_ADC_TSX2_AD13] = {
 290                 IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
 291         },
 292         [CPCAP_ADC_TSY1_AD14] = {
 293                 IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
 294         },
 295         [CPCAP_ADC_TSY2_AD15] = {
 296                 IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
 297         },
 298 };
 299
 300 /*
 301  * Temperature lookup table of register values to milliCelcius.
 302  * REVISIT: Check the duplicate 0x3ff entry in a freezer
 303  */
 304 static const int temp_map[CPCAP_MAX_TEMP_LVL][2] = {
 305         { 0x03ff, -40000 },
 306         { 0x03ff, -35000 },
 307         { 0x03ef, -30000 },
 308         { 0x03b2, -25000 },
 309         { 0x036c, -20000 },
 310         { 0x0320, -15000 },
 311         { 0x02d0, -10000 },
 312         { 0x027f, -5000 },
 313         { 0x022f, 0 },
 314         { 0x01e4, 5000 },
 315         { 0x019f, 10000 },
 316         { 0x0161, 15000 },
 317         { 0x012b, 20000 },
 318         { 0x00fc, 25000 },
 319         { 0x00d4, 30000 },
 320         { 0x00b2, 35000 },
 321         { 0x0095, 40000 },
 322         { 0x007d, 45000 },
 323         { 0x0069, 50000 },
 324         { 0x0059, 55000 },
 325         { 0x004b, 60000 },
 326         { 0x003f, 65000 },
 327         { 0x0036, 70000 },
 328         { 0x002e, 75000 },
 329         { 0x0027, 80000 },
 330         { 0x0022, 85000 },
 331         { 0x001d, 90000 },
 332 };
 333
 334 #define CPCAP_CHAN(_type, _index, _address, _datasheet_name) {  \
 335         .type = (_type), \
 336         .address = (_address), \
 337         .indexed = 1, \
 338         .channel = (_index), \
 339         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
 340                               BIT(IIO_CHAN_INFO_PROCESSED), \
 341         .scan_index = (_index), \
 342         .scan_type = { \
 343                 .sign = 'u', \
 344                 .realbits = 10, \
 345                 .storagebits = 16, \
 346                 .endianness = IIO_CPU, \
 347         }, \
 348         .datasheet_name = (_datasheet_name), \
 349 }
 350
 351 /*
 352  * The datasheet names are from Motorola mapphone Linux kernel except
 353  * for the last two which might be uncalibrated charge voltage and
 354  * current.
 355  */
 356 static const struct iio_chan_spec cpcap_adc_channels[] = {
 357         /* Bank0 */
 358         CPCAP_CHAN(IIO_TEMP,    0, CPCAP_REG_ADCD0,  "battdetb"),
 359         CPCAP_CHAN(IIO_VOLTAGE, 1, CPCAP_REG_ADCD1,  "battp"),
 360         CPCAP_CHAN(IIO_VOLTAGE, 2, CPCAP_REG_ADCD2,  "vbus"),
 361         CPCAP_CHAN(IIO_TEMP,    3, CPCAP_REG_ADCD3,  "ad3"),
 362         CPCAP_CHAN(IIO_VOLTAGE, 4, CPCAP_REG_ADCD4,  "ad4"),
 363         CPCAP_CHAN(IIO_CURRENT, 5, CPCAP_REG_ADCD5,  "chg_isense"),
 364         CPCAP_CHAN(IIO_CURRENT, 6, CPCAP_REG_ADCD6,  "batti"),
 365         CPCAP_CHAN(IIO_VOLTAGE, 7, CPCAP_REG_ADCD7,  "usb_id"),
 366
 367         /* Bank1 */
 368         CPCAP_CHAN(IIO_CURRENT, 8, CPCAP_REG_ADCD0,  "ad8"),
 369         CPCAP_CHAN(IIO_VOLTAGE, 9, CPCAP_REG_ADCD1,  "ad9"),
 370         CPCAP_CHAN(IIO_VOLTAGE, 10, CPCAP_REG_ADCD2, "licell"),
 371         CPCAP_CHAN(IIO_VOLTAGE, 11, CPCAP_REG_ADCD3, "hv_battp"),
 372         CPCAP_CHAN(IIO_VOLTAGE, 12, CPCAP_REG_ADCD4, "tsx1_ad12"),
 373         CPCAP_CHAN(IIO_VOLTAGE, 13, CPCAP_REG_ADCD5, "tsx2_ad13"),
 374         CPCAP_CHAN(IIO_VOLTAGE, 14, CPCAP_REG_ADCD6, "tsy1_ad14"),
 375         CPCAP_CHAN(IIO_VOLTAGE, 15, CPCAP_REG_ADCD7, "tsy2_ad15"),
 376
 377         /* There are two registers with multiplexed functionality */
 378         CPCAP_CHAN(IIO_VOLTAGE, 16, CPCAP_REG_ADCD0, "chg_vsense"),
 379         CPCAP_CHAN(IIO_CURRENT, 17, CPCAP_REG_ADCD1, "batti2"),
 380 };
 381
 382 static irqreturn_t cpcap_adc_irq_thread(int irq, void *data)
 383 {
 384         struct iio_dev *indio_dev = data;
 385         struct cpcap_adc *ddata = iio_priv(indio_dev);
 386         int error;
 387
 388         error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
 389                                    CPCAP_BIT_ADTRIG_DIS,
 390                                    CPCAP_BIT_ADTRIG_DIS);
 391         if (error)
 392                 return IRQ_NONE;
 393
 394         ddata->done = true;
 395         wake_up_interruptible(&ddata->wq_data_avail);
 396
 397         return IRQ_HANDLED;
 398 }
 399
 400 /* ADC calibration functions */
 401 static void cpcap_adc_setup_calibrate(struct cpcap_adc *ddata,
 402                                       enum cpcap_adc_channel chan)
 403 {
 404         unsigned int value = 0;
 405         unsigned long timeout = jiffies + msecs_to_jiffies(3000);
 406         int error;
 407
 408         if ((chan != CPCAP_ADC_CHG_ISENSE) &&
 409             (chan != CPCAP_ADC_BATTI))
 410                 return;
 411
 412         value |= CPCAP_BIT_CAL_MODE | CPCAP_BIT_RAND0;
 413         value |= ((chan << 4) &
 414                   (CPCAP_BIT_ADA2 | CPCAP_BIT_ADA1 | CPCAP_BIT_ADA0));
 415
 416         error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC1,
 417                                    CPCAP_BIT_CAL_MODE | CPCAP_BIT_ATOX |
 418                                    CPCAP_BIT_ATO3 | CPCAP_BIT_ATO2 |
 419                                    CPCAP_BIT_ATO1 | CPCAP_BIT_ATO0 |
 420                                    CPCAP_BIT_ADA2 | CPCAP_BIT_ADA1 |
 421                                    CPCAP_BIT_ADA0 | CPCAP_BIT_AD_SEL1 |
 422                                    CPCAP_BIT_RAND1 | CPCAP_BIT_RAND0,
 423                                    value);
 424         if (error)
 425                 return;
 426
 427         error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
 428                                    CPCAP_BIT_ATOX_PS_FACTOR |
 429                                    CPCAP_BIT_ADC_PS_FACTOR1 |
 430                                    CPCAP_BIT_ADC_PS_FACTOR0,
 431                                    0);
 432         if (error)
 433                 return;
 434
 435         error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
 436                                    CPCAP_BIT_ADTRIG_DIS,
 437                                    CPCAP_BIT_ADTRIG_DIS);
 438         if (error)
 439                 return;
 440
 441         error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
 442                                    CPCAP_BIT_ASC,
 443                                    CPCAP_BIT_ASC);
 444         if (error)
 445                 return;
 446
 447         do {
 448                 schedule_timeout_uninterruptible(1);
 449                 error = regmap_read(ddata->reg, CPCAP_REG_ADCC2, &value);
 450                 if (error)
 451                         return;
 452         } while ((value & CPCAP_BIT_ASC) && time_before(jiffies, timeout));
 453
 454         if (value & CPCAP_BIT_ASC)
 455                 dev_err(ddata->dev,
 456                         "Timeout waiting for calibration to complete\n");
 457
 458         error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC1,
 459                                    CPCAP_BIT_CAL_MODE, 0);
 460         if (error)
 461                 return;
 462 }
 463
 464 static int cpcap_adc_calibrate_one(struct cpcap_adc *ddata,
 465                                    int channel,
 466                                    u16 calibration_register,
 467                                    int lower_threshold,
 468                                    int upper_threshold)
 469 {
 470         unsigned int calibration_data[2];
 471         unsigned short cal_data_diff;
 472         int i, error;
 473
 474         for (i = 0; i < CPCAP_ADC_MAX_RETRIES; i++) {
 475                 calibration_data[0]  = 0;
 476                 calibration_data[1]  = 0;
 477                 cal_data_diff = 0;
 478                 cpcap_adc_setup_calibrate(ddata, channel);
 479                 error = regmap_read(ddata->reg, calibration_register,
 480                                     &calibration_data[0]);
 481                 if (error)
 482                         return error;
 483                 cpcap_adc_setup_calibrate(ddata, channel);
 484                 error = regmap_read(ddata->reg, calibration_register,
 485                                     &calibration_data[1]);
 486                 if (error)
 487                         return error;
 488
 489                 if (calibration_data[0] > calibration_data[1])
 490                         cal_data_diff =
 491                                 calibration_data[0] - calibration_data[1];
 492                 else
 493                         cal_data_diff =
 494                                 calibration_data[1] - calibration_data[0];
 495
 496                 if (((calibration_data[1] >= lower_threshold) &&
 497                      (calibration_data[1] <= upper_threshold) &&
 498                      (cal_data_diff <= ST_ADC_CALIBRATE_DIFF_THRESHOLD)) ||
 499                     (ddata->vendor == CPCAP_VENDOR_TI)) {
 500                         bank_conversion[channel].cal_offset =
 501                                 ((short)calibration_data[1] * -1) + 512;
 502                         dev_dbg(ddata->dev, "ch%i calibration complete: %i\n",
 503                                 channel, bank_conversion[channel].cal_offset);
 504                         break;
 505                 }
 506                 usleep_range(5000, 10000);
 507         }
 508
 509         return 0;
 510 }
 511
 512 static int cpcap_adc_calibrate(struct cpcap_adc *ddata)
 513 {
 514         int error;
 515
 516         error = cpcap_adc_calibrate_one(ddata, CPCAP_ADC_CHG_ISENSE,
 517                                         CPCAP_REG_ADCAL1,
 518                                         ST_ADC_CAL_CHRGI_LOW_THRESHOLD,
 519                                         ST_ADC_CAL_CHRGI_HIGH_THRESHOLD);
 520         if (error)
 521                 return error;
 522
 523         error = cpcap_adc_calibrate_one(ddata, CPCAP_ADC_BATTI,
 524                                         CPCAP_REG_ADCAL2,
 525                                         ST_ADC_CAL_BATTI_LOW_THRESHOLD,
 526                                         ST_ADC_CAL_BATTI_HIGH_THRESHOLD);
 527         if (error)
 528                 return error;
 529
 530         return 0;
 531 }
 532
 533 /* ADC setup, read and scale functions */
 534 static void cpcap_adc_setup_bank(struct cpcap_adc *ddata,
 535                                  struct cpcap_adc_request *req)
 536 {
 537         const struct cpcap_adc_ato *ato = ddata->ato;
 538         unsigned short value1 = 0;
 539         unsigned short value2 = 0;
 540         int error;
 541
 542         if (!ato)
 543                 return;
 544
 545         switch (req->channel) {
 546         case CPCAP_ADC_AD0:
 547                 value2 |= CPCAP_BIT_THERMBIAS_EN;
 548                 error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
 549                                            CPCAP_BIT_THERMBIAS_EN,
 550                                            value2);
 551                 if (error)
 552                         return;
 553                 usleep_range(800, 1000);
 554                 break;
 555         case CPCAP_ADC_AD8 ... CPCAP_ADC_TSY2_AD15:
 556                 value1 |= CPCAP_BIT_AD_SEL1;
 557                 break;
 558         case CPCAP_ADC_BATTP_PI16 ... CPCAP_ADC_BATTI_PI17:
 559                 value1 |= CPCAP_BIT_RAND1;
 560         default:
 561                 break;
 562         }
 563
 564         switch (req->timing) {
 565         case CPCAP_ADC_TIMING_IN:
 566                 value1 |= ato->ato_in;
 567                 value1 |= ato->atox_in;
 568                 value2 |= ato->adc_ps_factor_in;
 569                 value2 |= ato->atox_ps_factor_in;
 570                 break;
 571         case CPCAP_ADC_TIMING_OUT:
 572                 value1 |= ato->ato_out;
 573                 value1 |= ato->atox_out;
 574                 value2 |= ato->adc_ps_factor_out;
 575                 value2 |= ato->atox_ps_factor_out;
 576                 break;
 577
 578         case CPCAP_ADC_TIMING_IMM:
 579         default:
 580                 break;
 581         }
 582
 583         error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC1,
 584                                    CPCAP_BIT_CAL_MODE | CPCAP_BIT_ATOX |
 585                                    CPCAP_BIT_ATO3 | CPCAP_BIT_ATO2 |
 586                                    CPCAP_BIT_ATO1 | CPCAP_BIT_ATO0 |
 587                                    CPCAP_BIT_ADA2 | CPCAP_BIT_ADA1 |
 588                                    CPCAP_BIT_ADA0 | CPCAP_BIT_AD_SEL1 |
 589                                    CPCAP_BIT_RAND1 | CPCAP_BIT_RAND0,
 590                                    value1);
 591         if (error)
 592                 return;
 593
 594         error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
 595                                    CPCAP_BIT_ATOX_PS_FACTOR |
 596                                    CPCAP_BIT_ADC_PS_FACTOR1 |
 597                                    CPCAP_BIT_ADC_PS_FACTOR0 |
 598                                    CPCAP_BIT_THERMBIAS_EN,
 599                                    value2);
 600         if (error)
 601                 return;
 602
 603         if (req->timing == CPCAP_ADC_TIMING_IMM) {
 604                 error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
 605                                            CPCAP_BIT_ADTRIG_DIS,
 606                                            CPCAP_BIT_ADTRIG_DIS);
 607                 if (error)
 608                         return;
 609
 610                 error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
 611                                            CPCAP_BIT_ASC,
 612                                            CPCAP_BIT_ASC);
 613                 if (error)
 614                         return;
 615         } else {
 616                 error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
 617                                            CPCAP_BIT_ADTRIG_ONESHOT,
 618                                            CPCAP_BIT_ADTRIG_ONESHOT);
 619                 if (error)
 620                         return;
 621
 622                 error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
 623                                            CPCAP_BIT_ADTRIG_DIS, 0);
 624                 if (error)
 625                         return;
 626         }
 627 }
 628
 629 static int cpcap_adc_start_bank(struct cpcap_adc *ddata,
 630                                 struct cpcap_adc_request *req)
 631 {
 632         int i, error;
 633
 634         req->timing = CPCAP_ADC_TIMING_IMM;
 635         ddata->done = false;
 636
 637         for (i = 0; i < CPCAP_ADC_MAX_RETRIES; i++) {
 638                 cpcap_adc_setup_bank(ddata, req);
 639                 error = wait_event_interruptible_timeout(ddata->wq_data_avail,
 640                                                          ddata->done,
 641                                                          msecs_to_jiffies(50));
 642                 if (error > 0)
 643                         return 0;
 644
 645                 if (error == 0) {
 646                         error = -ETIMEDOUT;
 647                         continue;
 648                 }
 649
 650                 if (error < 0)
 651                         return error;
 652         }
 653
 654         return error;
 655 }
 656
 657 static int cpcap_adc_stop_bank(struct cpcap_adc *ddata)
 658 {
 659         int error;
 660
 661         error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC1,
 662                                    0xffff,
 663                                    CPCAP_REG_ADCC1_DEFAULTS);
 664         if (error)
 665                 return error;
 666
 667         return regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
 668                                   0xffff,
 669                                   CPCAP_REG_ADCC2_DEFAULTS);
 670 }
 671
 672 static void cpcap_adc_phase(struct cpcap_adc_request *req)
 673 {
 674         const struct cpcap_adc_conversion_tbl *conv_tbl = req->conv_tbl;
 675         const struct cpcap_adc_phasing_tbl *phase_tbl = req->phase_tbl;
 676         int index = req->channel;
 677
 678         /* Remuxed channels 16 and 17 use BATTP and BATTI entries */
 679         switch (req->channel) {
 680         case CPCAP_ADC_BATTP:
 681         case CPCAP_ADC_BATTP_PI16:
 682                 index = req->bank_index;
 683                 req->result -= phase_tbl[index].offset;
 684                 req->result -= CPCAP_FOUR_POINT_TWO_ADC;
 685                 req->result *= phase_tbl[index].multiplier;
 686                 if (phase_tbl[index].divider == 0)
 687                         return;
 688                 req->result /= phase_tbl[index].divider;
 689                 req->result += CPCAP_FOUR_POINT_TWO_ADC;
 690                 break;
 691         case CPCAP_ADC_BATTI_PI17:
 692                 index = req->bank_index;
 693                 fallthrough;
 694         default:
 695                 req->result += conv_tbl[index].cal_offset;
 696                 req->result += conv_tbl[index].align_offset;
 697                 req->result *= phase_tbl[index].multiplier;
 698                 if (phase_tbl[index].divider == 0)
 699                         return;
 700                 req->result /= phase_tbl[index].divider;
 701                 req->result += phase_tbl[index].offset;
 702                 break;
 703         }
 704
 705         if (req->result < phase_tbl[index].min)
 706                 req->result = phase_tbl[index].min;
 707         else if (req->result > phase_tbl[index].max)
 708                 req->result = phase_tbl[index].max;
 709 }
 710
 711 /* Looks up temperatures in a table and calculates averages if needed */
 712 static int cpcap_adc_table_to_millicelcius(unsigned short value)
 713 {
 714         int i, result = 0, alpha;
 715
 716         if (value <= temp_map[CPCAP_MAX_TEMP_LVL - 1][0])
 717                 return temp_map[CPCAP_MAX_TEMP_LVL - 1][1];
 718
 719         if (value >= temp_map[0][0])
 720                 return temp_map[0][1];
 721
 722         for (i = 0; i < CPCAP_MAX_TEMP_LVL - 1; i++) {
 723                 if ((value <= temp_map[i][0]) &&
 724                     (value >= temp_map[i + 1][0])) {
 725                         if (value == temp_map[i][0]) {
 726                                 result = temp_map[i][1];
 727                         } else if (value == temp_map[i + 1][0]) {
 728                                 result = temp_map[i + 1][1];
 729                         } else {
 730                                 alpha = ((value - temp_map[i][0]) * 1000) /
 731                                         (temp_map[i + 1][0] - temp_map[i][0]);
 732
 733                                 result = temp_map[i][1] +
 734                                         ((alpha * (temp_map[i + 1][1] -
 735                                                  temp_map[i][1])) / 1000);
 736                         }
 737                         break;
 738                 }
 739         }
 740
 741         return result;
 742 }
 743
 744 static void cpcap_adc_convert(struct cpcap_adc_request *req)
 745 {
 746         const struct cpcap_adc_conversion_tbl *conv_tbl = req->conv_tbl;
 747         int index = req->channel;
 748
 749         /* Remuxed channels 16 and 17 use BATTP and BATTI entries */
 750         switch (req->channel) {
 751         case CPCAP_ADC_BATTP_PI16:
 752                 index = CPCAP_ADC_BATTP;
 753                 break;
 754         case CPCAP_ADC_BATTI_PI17:
 755                 index = CPCAP_ADC_BATTI;
 756                 break;
 757         default:
 758                 break;
 759         }
 760
 761         /* No conversion for raw channels */
 762         if (conv_tbl[index].conv_type == IIO_CHAN_INFO_RAW)
 763                 return;
 764
 765         /* Temperatures use a lookup table instead of conversion table */
 766         if ((req->channel == CPCAP_ADC_AD0) ||
 767             (req->channel == CPCAP_ADC_AD3)) {
 768                 req->result =
 769                         cpcap_adc_table_to_millicelcius(req->result);
 770
 771                 return;
 772         }
 773
 774         /* All processed channels use a conversion table */
 775         req->result *= conv_tbl[index].multiplier;
 776         if (conv_tbl[index].divider == 0)
 777                 return;
 778         req->result /= conv_tbl[index].divider;
 779         req->result += conv_tbl[index].conv_offset;
 780 }
 781
 782 /*
 783  * REVISIT: Check if timed sampling can use multiple channels at the
 784  * same time. If not, replace channel_mask with just channel.
 785  */
 786 static int cpcap_adc_read_bank_scaled(struct cpcap_adc *ddata,
 787                                       struct cpcap_adc_request *req)
 788 {
 789         int calibration_data, error, addr;
 790
 791         if (ddata->vendor == CPCAP_VENDOR_TI) {
 792                 error = regmap_read(ddata->reg, CPCAP_REG_ADCAL1,
 793                                     &calibration_data);
 794                 if (error)
 795                         return error;
 796                 bank_conversion[CPCAP_ADC_CHG_ISENSE].cal_offset =
 797                         ((short)calibration_data * -1) + 512;
 798
 799                 error = regmap_read(ddata->reg, CPCAP_REG_ADCAL2,
 800                                     &calibration_data);
 801                 if (error)
 802                         return error;
 803                 bank_conversion[CPCAP_ADC_BATTI].cal_offset =
 804                         ((short)calibration_data * -1) + 512;
 805         }
 806
 807         addr = CPCAP_REG_ADCD0 + req->bank_index * 4;
 808
 809         error = regmap_read(ddata->reg, addr, &req->result);
 810         if (error)
 811                 return error;
 812
 813         req->result &= 0x3ff;
 814         cpcap_adc_phase(req);
 815         cpcap_adc_convert(req);
 816
 817         return 0;
 818 }
 819
 820 static int cpcap_adc_init_request(struct cpcap_adc_request *req,
 821                                   int channel)
 822 {
 823         req->channel = channel;
 824         req->phase_tbl = bank_phasing;
 825         req->conv_tbl = bank_conversion;
 826
 827         switch (channel) {
 828         case CPCAP_ADC_AD0 ... CPCAP_ADC_USB_ID:
 829                 req->bank_index = channel;
 830                 break;
 831         case CPCAP_ADC_AD8 ... CPCAP_ADC_TSY2_AD15:
 832                 req->bank_index = channel - 8;
 833                 break;
 834         case CPCAP_ADC_BATTP_PI16:
 835                 req->bank_index = CPCAP_ADC_BATTP;
 836                 break;
 837         case CPCAP_ADC_BATTI_PI17:
 838                 req->bank_index = CPCAP_ADC_BATTI;
 839                 break;
 840         default:
 841                 return -EINVAL;
 842         }
 843
 844         return 0;
 845 }
 846
 847 static int cpcap_adc_read_st_die_temp(struct cpcap_adc *ddata,
 848                                       int addr, int *val)
 849 {
 850         int error;
 851
 852         error = regmap_read(ddata->reg, addr, val);
 853         if (error)
 854                 return error;
 855
 856         *val -= 282;
 857         *val *= 114;
 858         *val += 25000;
 859
 860         return 0;
 861 }
 862
 863 static int cpcap_adc_read(struct iio_dev *indio_dev,
 864                           struct iio_chan_spec const *chan,
 865                           int *val, int *val2, long mask)
 866 {
 867         struct cpcap_adc *ddata = iio_priv(indio_dev);
 868         struct cpcap_adc_request req;
 869         int error;
 870
 871         error = cpcap_adc_init_request(&req, chan->channel);
 872         if (error)
 873                 return error;
 874
 875         switch (mask) {
 876         case IIO_CHAN_INFO_RAW:
 877                 mutex_lock(&ddata->lock);
 878                 error = cpcap_adc_start_bank(ddata, &req);
 879                 if (error)
 880                         goto err_unlock;
 881                 error = regmap_read(ddata->reg, chan->address, val);
 882                 if (error)
 883                         goto err_unlock;
 884                 error = cpcap_adc_stop_bank(ddata);
 885                 if (error)
 886                         goto err_unlock;
 887                 mutex_unlock(&ddata->lock);
 888                 break;
 889         case IIO_CHAN_INFO_PROCESSED:
 890                 mutex_lock(&ddata->lock);
 891                 error = cpcap_adc_start_bank(ddata, &req);
 892                 if (error)
 893                         goto err_unlock;
 894                 if ((ddata->vendor == CPCAP_VENDOR_ST) &&
 895                     (chan->channel == CPCAP_ADC_AD3)) {
 896                         error = cpcap_adc_read_st_die_temp(ddata,
 897                                                            chan->address,
 898                                                            &req.result);
 899                         if (error)
 900                                 goto err_unlock;
 901                 } else {
 902                         error = cpcap_adc_read_bank_scaled(ddata, &req);
 903                         if (error)
 904                                 goto err_unlock;
 905                 }
 906                 error = cpcap_adc_stop_bank(ddata);
 907                 if (error)
 908                         goto err_unlock;
 909                 mutex_unlock(&ddata->lock);
 910                 *val = req.result;
 911                 break;
 912         default:
 913                 return -EINVAL;
 914         }
 915
 916         return IIO_VAL_INT;
 917
 918 err_unlock:
 919         mutex_unlock(&ddata->lock);
 920         dev_err(ddata->dev, "error reading ADC: %i\n", error);
 921
 922         return error;
 923 }
 924
 925 static const struct iio_info cpcap_adc_info = {
 926         .read_raw = &cpcap_adc_read,
 927 };
 928
 929 /*
 930  * Configuration for Motorola mapphone series such as droid 4.
 931  * Copied from the Motorola mapphone kernel tree.
 932  */
 933 static const struct cpcap_adc_ato mapphone_adc = {
 934         .ato_in = 0x0480,
 935         .atox_in = 0,
 936         .adc_ps_factor_in = 0x0200,
 937         .atox_ps_factor_in = 0,
 938         .ato_out = 0,
 939         .atox_out = 0,
 940         .adc_ps_factor_out = 0,
 941         .atox_ps_factor_out = 0,
 942 };
 943
 944 static const struct of_device_id cpcap_adc_id_table[] = {
 945         {
 946                 .compatible = "motorola,cpcap-adc",
 947         },
 948         {
 949                 .compatible = "motorola,mapphone-cpcap-adc",
 950                 .data = &mapphone_adc,
 951         },
 952         { /* sentinel */ },
 953 };
 954 MODULE_DEVICE_TABLE(of, cpcap_adc_id_table);
 955
 956 static int cpcap_adc_probe(struct platform_device *pdev)
 957 {
 958         struct cpcap_adc *ddata;
 959         struct iio_dev *indio_dev;
 960         int error;
 961
 962         indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*ddata));
 963         if (!indio_dev) {
 964                 dev_err(&pdev->dev, "failed to allocate iio device\n");
 965
 966                 return -ENOMEM;
 967         }
 968         ddata = iio_priv(indio_dev);
 969         ddata->ato = device_get_match_data(&pdev->dev);
 970         if (!ddata->ato)
 971                 return -ENODEV;
 972         ddata->dev = &pdev->dev;
 973
 974         mutex_init(&ddata->lock);
 975         init_waitqueue_head(&ddata->wq_data_avail);
 976
 977         indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
 978         indio_dev->channels = cpcap_adc_channels;
 979         indio_dev->num_channels = ARRAY_SIZE(cpcap_adc_channels);
 980         indio_dev->name = dev_name(&pdev->dev);
 981         indio_dev->info = &cpcap_adc_info;
 982
 983         ddata->reg = dev_get_regmap(pdev->dev.parent, NULL);
 984         if (!ddata->reg)
 985                 return -ENODEV;
 986
 987         error = cpcap_get_vendor(ddata->dev, ddata->reg, &ddata->vendor);
 988         if (error)
 989                 return error;
 990
 991         platform_set_drvdata(pdev, indio_dev);
 992
 993         ddata->irq = platform_get_irq_byname(pdev, "adcdone");
 994         if (ddata->irq < 0)
 995                 return -ENODEV;
 996
 997         error = devm_request_threaded_irq(&pdev->dev, ddata->irq, NULL,
 998                                           cpcap_adc_irq_thread,
 999                                           IRQF_TRIGGER_NONE | IRQF_ONESHOT,
1000                                           "cpcap-adc", indio_dev);
1001         if (error) {
1002                 dev_err(&pdev->dev, "could not get irq: %i\n",
1003                         error);
1004
1005                 return error;
1006         }
1007
1008         error = cpcap_adc_calibrate(ddata);
1009         if (error)
1010                 return error;
1011
1012         dev_info(&pdev->dev, "CPCAP ADC device probed\n");
1013
1014         return devm_iio_device_register(&pdev->dev, indio_dev);
1015 }
1016
1017 static struct platform_driver cpcap_adc_driver = {
1018         .driver = {
1019                 .name = "cpcap_adc",
1020                 .of_match_table = cpcap_adc_id_table,
1021         },
1022         .probe = cpcap_adc_probe,
1023 };
1024
1025 module_platform_driver(cpcap_adc_driver);
1026
1027 MODULE_ALIAS("platform:cpcap_adc");
1028 MODULE_DESCRIPTION("CPCAP ADC driver");
1029 MODULE_AUTHOR("Tony Lindgren <tony@atomide.com");
1030 MODULE_LICENSE("GPL v2");