LXR linux/drivers/iio/adc/twl6030-gpadc.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * TWL6030 GPADC module driver
   4 *
   5 * Copyright (C) 2009-2013 Texas Instruments Inc.
   6 * Nishant Kamat <nskamat@ti.com>
   7 * Balaji T K <balajitk@ti.com>
   8 * Graeme Gregory <gg@slimlogic.co.uk>
   9 * Girish S Ghongdemath <girishsg@ti.com>
  10 * Ambresh K <ambresh@ti.com>
  11 * Oleksandr Kozaruk <oleksandr.kozaruk@ti.com
  12 *
  13 * Based on twl4030-madc.c
  14 * Copyright (C) 2008 Nokia Corporation
  15 * Mikko Ylinen <mikko.k.ylinen@nokia.com>
  16 */
  17#include <linux/interrupt.h>
  18#include <linux/kernel.h>
  19#include <linux/module.h>
  20#include <linux/platform_device.h>
  21#include <linux/of_platform.h>
  22#include <linux/mfd/twl.h>
  23#include <linux/iio/iio.h>
  24#include <linux/iio/sysfs.h>
  25
  26#define DRIVER_NAME             "twl6030_gpadc"
  27
  28/*
  29 * twl6030 per TRM has 17 channels, and twl6032 has 19 channels
  30 * 2 test network channels are not used,
  31 * 2 die temperature channels are not used either, as it is not
  32 * defined how to convert ADC value to temperature
  33 */
  34#define TWL6030_GPADC_USED_CHANNELS             13
  35#define TWL6030_GPADC_MAX_CHANNELS              15
  36#define TWL6032_GPADC_USED_CHANNELS             15
  37#define TWL6032_GPADC_MAX_CHANNELS              19
  38#define TWL6030_GPADC_NUM_TRIM_REGS             16
  39
  40#define TWL6030_GPADC_CTRL_P1                   0x05
  41
  42#define TWL6032_GPADC_GPSELECT_ISB              0x07
  43#define TWL6032_GPADC_CTRL_P1                   0x08
  44
  45#define TWL6032_GPADC_GPCH0_LSB                 0x0d
  46#define TWL6032_GPADC_GPCH0_MSB                 0x0e
  47
  48#define TWL6030_GPADC_CTRL_P1_SP1               BIT(3)
  49
  50#define TWL6030_GPADC_GPCH0_LSB                 (0x29)
  51
  52#define TWL6030_GPADC_RT_SW1_EOC_MASK           BIT(5)
  53
  54#define TWL6030_GPADC_TRIM1                     0xCD
  55
  56#define TWL6030_REG_TOGGLE1                     0x90
  57#define TWL6030_GPADCS                          BIT(1)
  58#define TWL6030_GPADCR                          BIT(0)
  59
  60/**
  61 * struct twl6030_chnl_calib - channel calibration
  62 * @gain:               slope coefficient for ideal curve
  63 * @gain_error:         gain error
  64 * @offset_error:       offset of the real curve
  65 */
  66struct twl6030_chnl_calib {
  67        s32 gain;
  68        s32 gain_error;
  69        s32 offset_error;
  70};
  71
  72/**
  73 * struct twl6030_ideal_code - GPADC calibration parameters
  74 * GPADC is calibrated in two points: close to the beginning and
  75 * to the and of the measurable input range
  76 *
  77 * @channel:    channel number
  78 * @code1:      ideal code for the input at the beginning
  79 * @code2:      ideal code for at the end of the range
  80 * @volt1:      voltage input at the beginning(low voltage)
  81 * @volt2:      voltage input at the end(high voltage)
  82 */
  83struct twl6030_ideal_code {
  84        int channel;
  85        u16 code1;
  86        u16 code2;
  87        u16 volt1;
  88        u16 volt2;
  89};
  90
  91struct twl6030_gpadc_data;
  92
  93/**
  94 * struct twl6030_gpadc_platform_data - platform specific data
  95 * @nchannels:          number of GPADC channels
  96 * @iio_channels:       iio channels
  97 * @ideal:              pointer to calibration parameters
  98 * @start_conversion:   pointer to ADC start conversion function
  99 * @channel_to_reg:     pointer to ADC function to convert channel to
 100 *                      register address for reading conversion result
 101 * @calibrate:          pointer to calibration function
 102 */
 103struct twl6030_gpadc_platform_data {
 104        const int nchannels;
 105        const struct iio_chan_spec *iio_channels;
 106        const struct twl6030_ideal_code *ideal;
 107        int (*start_conversion)(int channel);
 108        u8 (*channel_to_reg)(int channel);
 109        int (*calibrate)(struct twl6030_gpadc_data *gpadc);
 110};
 111
 112/**
 113 * struct twl6030_gpadc_data - GPADC data
 114 * @dev:                device pointer
 115 * @lock:               mutual exclusion lock for the structure
 116 * @irq_complete:       completion to signal end of conversion
 117 * @twl6030_cal_tbl:    pointer to calibration data for each
 118 *                      channel with gain error and offset
 119 * @pdata:              pointer to device specific data
 120 */
 121struct twl6030_gpadc_data {
 122        struct device   *dev;
 123        struct mutex    lock;
 124        struct completion       irq_complete;
 125        struct twl6030_chnl_calib       *twl6030_cal_tbl;
 126        const struct twl6030_gpadc_platform_data *pdata;
 127};
 128
 129/*
 130 * channels 11, 12, 13, 15 and 16 have no calibration data
 131 * calibration offset is same for channels 1, 3, 4, 5
 132 *
 133 * The data is taken from GPADC_TRIM registers description.
 134 * GPADC_TRIM registers keep difference between the code measured
 135 * at volt1 and volt2 input voltages and corresponding code1 and code2
 136 */
 137static const struct twl6030_ideal_code
 138        twl6030_ideal[TWL6030_GPADC_USED_CHANNELS] = {
 139        [0] = { /* ch 0, external, battery type, resistor value */
 140                .channel = 0,
 141                .code1 = 116,
 142                .code2 = 745,
 143                .volt1 = 141,
 144                .volt2 = 910,
 145        },
 146        [1] = { /* ch 1, external, battery temperature, NTC resistor value */
 147                .channel = 1,
 148                .code1 = 82,
 149                .code2 = 900,
 150                .volt1 = 100,
 151                .volt2 = 1100,
 152        },
 153        [2] = { /* ch 2, external, audio accessory/general purpose */
 154                .channel = 2,
 155                .code1 = 55,
 156                .code2 = 818,
 157                .volt1 = 101,
 158                .volt2 = 1499,
 159        },
 160        [3] = { /* ch 3, external, general purpose */
 161                .channel = 3,
 162                .code1 = 82,
 163                .code2 = 900,
 164                .volt1 = 100,
 165                .volt2 = 1100,
 166        },
 167        [4] = { /* ch 4, external, temperature measurement/general purpose */
 168                .channel = 4,
 169                .code1 = 82,
 170                .code2 = 900,
 171                .volt1 = 100,
 172                .volt2 = 1100,
 173        },
 174        [5] = { /* ch 5, external, general purpose */
 175                .channel = 5,
 176                .code1 = 82,
 177                .code2 = 900,
 178                .volt1 = 100,
 179                .volt2 = 1100,
 180        },
 181        [6] = { /* ch 6, external, general purpose */
 182                .channel = 6,
 183                .code1 = 82,
 184                .code2 = 900,
 185                .volt1 = 100,
 186                .volt2 = 1100,
 187        },
 188        [7] = { /* ch 7, internal, main battery */
 189                .channel = 7,
 190                .code1 = 614,
 191                .code2 = 941,
 192                .volt1 = 3001,
 193                .volt2 = 4599,
 194        },
 195        [8] = { /* ch 8, internal, backup battery */
 196                .channel = 8,
 197                .code1 = 82,
 198                .code2 = 688,
 199                .volt1 = 501,
 200                .volt2 = 4203,
 201        },
 202        [9] = { /* ch 9, internal, external charger input */
 203                .channel = 9,
 204                .code1 = 182,
 205                .code2 = 818,
 206                .volt1 = 2001,
 207                .volt2 = 8996,
 208        },
 209        [10] = { /* ch 10, internal, VBUS */
 210                .channel = 10,
 211                .code1 = 149,
 212                .code2 = 818,
 213                .volt1 = 1001,
 214                .volt2 = 5497,
 215        },
 216        [11] = { /* ch 11, internal, VBUS charging current */
 217                .channel = 11,
 218        },
 219                /* ch 12, internal, Die temperature */
 220                /* ch 13, internal, Die temperature */
 221        [12] = { /* ch 14, internal, USB ID line */
 222                .channel = 14,
 223                .code1 = 48,
 224                .code2 = 714,
 225                .volt1 = 323,
 226                .volt2 = 4800,
 227        },
 228};
 229
 230static const struct twl6030_ideal_code
 231                        twl6032_ideal[TWL6032_GPADC_USED_CHANNELS] = {
 232        [0] = { /* ch 0, external, battery type, resistor value */
 233                .channel = 0,
 234                .code1 = 1441,
 235                .code2 = 3276,
 236                .volt1 = 440,
 237                .volt2 = 1000,
 238        },
 239        [1] = { /* ch 1, external, battery temperature, NTC resistor value */
 240                .channel = 1,
 241                .code1 = 1441,
 242                .code2 = 3276,
 243                .volt1 = 440,
 244                .volt2 = 1000,
 245        },
 246        [2] = { /* ch 2, external, audio accessory/general purpose */
 247                .channel = 2,
 248                .code1 = 1441,
 249                .code2 = 3276,
 250                .volt1 = 660,
 251                .volt2 = 1500,
 252        },
 253        [3] = { /* ch 3, external, temperature with external diode/general
 254                                                                purpose */
 255                .channel = 3,
 256                .code1 = 1441,
 257                .code2 = 3276,
 258                .volt1 = 440,
 259                .volt2 = 1000,
 260        },
 261        [4] = { /* ch 4, external, temperature measurement/general purpose */
 262                .channel = 4,
 263                .code1 = 1441,
 264                .code2 = 3276,
 265                .volt1 = 440,
 266                .volt2 = 1000,
 267        },
 268        [5] = { /* ch 5, external, general purpose */
 269                .channel = 5,
 270                .code1 = 1441,
 271                .code2 = 3276,
 272                .volt1 = 440,
 273                .volt2 = 1000,
 274        },
 275        [6] = { /* ch 6, external, general purpose */
 276                .channel = 6,
 277                .code1 = 1441,
 278                .code2 = 3276,
 279                .volt1 = 440,
 280                .volt2 = 1000,
 281        },
 282        [7] = { /* ch7, internal, system supply */
 283                .channel = 7,
 284                .code1 = 1441,
 285                .code2 = 3276,
 286                .volt1 = 2200,
 287                .volt2 = 5000,
 288        },
 289        [8] = { /* ch8, internal, backup battery */
 290                .channel = 8,
 291                .code1 = 1441,
 292                .code2 = 3276,
 293                .volt1 = 2200,
 294                .volt2 = 5000,
 295        },
 296        [9] = { /* ch 9, internal, external charger input */
 297                .channel = 9,
 298                .code1 = 1441,
 299                .code2 = 3276,
 300                .volt1 = 3960,
 301                .volt2 = 9000,
 302        },
 303        [10] = { /* ch10, internal, VBUS */
 304                .channel = 10,
 305                .code1 = 150,
 306                .code2 = 751,
 307                .volt1 = 1000,
 308                .volt2 = 5000,
 309        },
 310        [11] = { /* ch 11, internal, VBUS DC-DC output current */
 311                .channel = 11,
 312                .code1 = 1441,
 313                .code2 = 3276,
 314                .volt1 = 660,
 315                .volt2 = 1500,
 316        },
 317                /* ch 12, internal, Die temperature */
 318                /* ch 13, internal, Die temperature */
 319        [12] = { /* ch 14, internal, USB ID line */
 320                .channel = 14,
 321                .code1 = 1441,
 322                .code2 = 3276,
 323                .volt1 = 2420,
 324                .volt2 = 5500,
 325        },
 326                /* ch 15, internal, test network */
 327                /* ch 16, internal, test network */
 328        [13] = { /* ch 17, internal, battery charging current */
 329                .channel = 17,
 330        },
 331        [14] = { /* ch 18, internal, battery voltage */
 332                .channel = 18,
 333                .code1 = 1441,
 334                .code2 = 3276,
 335                .volt1 = 2200,
 336                .volt2 = 5000,
 337        },
 338};
 339
 340static inline int twl6030_gpadc_write(u8 reg, u8 val)
 341{
 342        return twl_i2c_write_u8(TWL6030_MODULE_GPADC, val, reg);
 343}
 344
 345static inline int twl6030_gpadc_read(u8 reg, u8 *val)
 346{
 347
 348        return twl_i2c_read(TWL6030_MODULE_GPADC, val, reg, 2);
 349}
 350
 351static int twl6030_gpadc_enable_irq(u8 mask)
 352{
 353        int ret;
 354
 355        ret = twl6030_interrupt_unmask(mask, REG_INT_MSK_LINE_B);
 356        if (ret < 0)
 357                return ret;
 358
 359        ret = twl6030_interrupt_unmask(mask, REG_INT_MSK_STS_B);
 360
 361        return ret;
 362}
 363
 364static void twl6030_gpadc_disable_irq(u8 mask)
 365{
 366        twl6030_interrupt_mask(mask, REG_INT_MSK_LINE_B);
 367        twl6030_interrupt_mask(mask, REG_INT_MSK_STS_B);
 368}
 369
 370static irqreturn_t twl6030_gpadc_irq_handler(int irq, void *indio_dev)
 371{
 372        struct twl6030_gpadc_data *gpadc = iio_priv(indio_dev);
 373
 374        complete(&gpadc->irq_complete);
 375
 376        return IRQ_HANDLED;
 377}
 378
 379static int twl6030_start_conversion(int channel)
 380{
 381        return twl6030_gpadc_write(TWL6030_GPADC_CTRL_P1,
 382                                        TWL6030_GPADC_CTRL_P1_SP1);
 383}
 384
 385static int twl6032_start_conversion(int channel)
 386{
 387        int ret;
 388
 389        ret = twl6030_gpadc_write(TWL6032_GPADC_GPSELECT_ISB, channel);
 390        if (ret)
 391                return ret;
 392
 393        return twl6030_gpadc_write(TWL6032_GPADC_CTRL_P1,
 394                                                TWL6030_GPADC_CTRL_P1_SP1);
 395}
 396
 397static u8 twl6030_channel_to_reg(int channel)
 398{
 399        return TWL6030_GPADC_GPCH0_LSB + 2 * channel;
 400}
 401
 402static u8 twl6032_channel_to_reg(int channel)
 403{
 404        /*
 405         * for any prior chosen channel, when the conversion is ready
 406         * the result is avalable in GPCH0_LSB, GPCH0_MSB.
 407         */
 408
 409        return TWL6032_GPADC_GPCH0_LSB;
 410}
 411
 412static int twl6030_gpadc_lookup(const struct twl6030_ideal_code *ideal,
 413                int channel, int size)
 414{
 415        int i;
 416
 417        for (i = 0; i < size; i++)
 418                if (ideal[i].channel == channel)
 419                        break;
 420
 421        return i;
 422}
 423
 424static int twl6030_channel_calibrated(const struct twl6030_gpadc_platform_data
 425                *pdata, int channel)
 426{
 427        const struct twl6030_ideal_code *ideal = pdata->ideal;
 428        int i;
 429
 430        i = twl6030_gpadc_lookup(ideal, channel, pdata->nchannels);
 431        /* not calibrated channels have 0 in all structure members */
 432        return pdata->ideal[i].code2;
 433}
 434
 435static int twl6030_gpadc_make_correction(struct twl6030_gpadc_data *gpadc,
 436                int channel, int raw_code)
 437{
 438        const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
 439        int corrected_code;
 440        int i;
 441
 442        i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
 443        corrected_code = ((raw_code * 1000) -
 444                gpadc->twl6030_cal_tbl[i].offset_error) /
 445                gpadc->twl6030_cal_tbl[i].gain_error;
 446
 447        return corrected_code;
 448}
 449
 450static int twl6030_gpadc_get_raw(struct twl6030_gpadc_data *gpadc,
 451                int channel, int *res)
 452{
 453        u8 reg = gpadc->pdata->channel_to_reg(channel);
 454        __le16 val;
 455        int raw_code;
 456        int ret;
 457
 458        ret = twl6030_gpadc_read(reg, (u8 *)&val);
 459        if (ret) {
 460                dev_dbg(gpadc->dev, "unable to read register 0x%X\n", reg);
 461                return ret;
 462        }
 463
 464        raw_code = le16_to_cpu(val);
 465        dev_dbg(gpadc->dev, "GPADC raw code: %d", raw_code);
 466
 467        if (twl6030_channel_calibrated(gpadc->pdata, channel))
 468                *res = twl6030_gpadc_make_correction(gpadc, channel, raw_code);
 469        else
 470                *res = raw_code;
 471
 472        return ret;
 473}
 474
 475static int twl6030_gpadc_get_processed(struct twl6030_gpadc_data *gpadc,
 476                int channel, int *val)
 477{
 478        const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
 479        int corrected_code;
 480        int channel_value;
 481        int i;
 482        int ret;
 483
 484        ret = twl6030_gpadc_get_raw(gpadc, channel, &corrected_code);
 485        if (ret)
 486                return ret;
 487
 488        i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
 489        channel_value = corrected_code *
 490                        gpadc->twl6030_cal_tbl[i].gain;
 491
 492        /* Shift back into mV range */
 493        channel_value /= 1000;
 494
 495        dev_dbg(gpadc->dev, "GPADC corrected code: %d", corrected_code);
 496        dev_dbg(gpadc->dev, "GPADC value: %d", channel_value);
 497
 498        *val = channel_value;
 499
 500        return ret;
 501}
 502
 503static int twl6030_gpadc_read_raw(struct iio_dev *indio_dev,
 504                             const struct iio_chan_spec *chan,
 505                             int *val, int *val2, long mask)
 506{
 507        struct twl6030_gpadc_data *gpadc = iio_priv(indio_dev);
 508        int ret;
 509        long timeout;
 510
 511        mutex_lock(&gpadc->lock);
 512
 513        ret = gpadc->pdata->start_conversion(chan->channel);
 514        if (ret) {
 515                dev_err(gpadc->dev, "failed to start conversion\n");
 516                goto err;
 517        }
 518        /* wait for conversion to complete */
 519        timeout = wait_for_completion_interruptible_timeout(
 520                                &gpadc->irq_complete, msecs_to_jiffies(5000));
 521        if (timeout == 0) {
 522                ret = -ETIMEDOUT;
 523                goto err;
 524        } else if (timeout < 0) {
 525                ret = -EINTR;
 526                goto err;
 527        }
 528
 529        switch (mask) {
 530        case IIO_CHAN_INFO_RAW:
 531                ret = twl6030_gpadc_get_raw(gpadc, chan->channel, val);
 532                ret = ret ? -EIO : IIO_VAL_INT;
 533                break;
 534
 535        case IIO_CHAN_INFO_PROCESSED:
 536                ret = twl6030_gpadc_get_processed(gpadc, chan->channel, val);
 537                ret = ret ? -EIO : IIO_VAL_INT;
 538                break;
 539
 540        default:
 541                break;
 542        }
 543err:
 544        mutex_unlock(&gpadc->lock);
 545
 546        return ret;
 547}
 548
 549/*
 550 * The GPADC channels are calibrated using a two point calibration method.
 551 * The channels measured with two known values: volt1 and volt2, and
 552 * ideal corresponding output codes are known: code1, code2.
 553 * The difference(d1, d2) between ideal and measured codes stored in trim
 554 * registers.
 555 * The goal is to find offset and gain of the real curve for each calibrated
 556 * channel.
 557 * gain: k = 1 + ((d2 - d1) / (x2 - x1))
 558 * offset: b = d1 + (k - 1) * x1
 559 */
 560static void twl6030_calibrate_channel(struct twl6030_gpadc_data *gpadc,
 561                int channel, int d1, int d2)
 562{
 563        int b, k, gain, x1, x2, i;
 564        const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
 565
 566        i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
 567
 568        /* Gain */
 569        gain = ((ideal[i].volt2 - ideal[i].volt1) * 1000) /
 570                (ideal[i].code2 - ideal[i].code1);
 571
 572        x1 = ideal[i].code1;
 573        x2 = ideal[i].code2;
 574
 575        /* k - real curve gain */
 576        k = 1000 + (((d2 - d1) * 1000) / (x2 - x1));
 577
 578        /* b - offset of the real curve gain */
 579        b = (d1 * 1000) - (k - 1000) * x1;
 580
 581        gpadc->twl6030_cal_tbl[i].gain = gain;
 582        gpadc->twl6030_cal_tbl[i].gain_error = k;
 583        gpadc->twl6030_cal_tbl[i].offset_error = b;
 584
 585        dev_dbg(gpadc->dev, "GPADC d1   for Chn: %d = %d\n", channel, d1);
 586        dev_dbg(gpadc->dev, "GPADC d2   for Chn: %d = %d\n", channel, d2);
 587        dev_dbg(gpadc->dev, "GPADC x1   for Chn: %d = %d\n", channel, x1);
 588        dev_dbg(gpadc->dev, "GPADC x2   for Chn: %d = %d\n", channel, x2);
 589        dev_dbg(gpadc->dev, "GPADC Gain for Chn: %d = %d\n", channel, gain);
 590        dev_dbg(gpadc->dev, "GPADC k    for Chn: %d = %d\n", channel, k);
 591        dev_dbg(gpadc->dev, "GPADC b    for Chn: %d = %d\n", channel, b);
 592}
 593
 594static inline int twl6030_gpadc_get_trim_offset(s8 d)
 595{
 596        /*
 597         * XXX NOTE!
 598         * bit 0 - sign, bit 7 - reserved, 6..1 - trim value
 599         * though, the documentation states that trim value
 600         * is absolute value, the correct conversion results are
 601         * obtained if the value is interpreted as 2's complement.
 602         */
 603        __u32 temp = ((d & 0x7f) >> 1) | ((d & 1) << 6);
 604
 605        return sign_extend32(temp, 6);
 606}
 607
 608static int twl6030_calibration(struct twl6030_gpadc_data *gpadc)
 609{
 610        int ret;
 611        int chn;
 612        u8 trim_regs[TWL6030_GPADC_NUM_TRIM_REGS];
 613        s8 d1, d2;
 614
 615        /*
 616         * for calibration two measurements have been performed at
 617         * factory, for some channels, during the production test and
 618         * have been stored in registers. This two stored values are
 619         * used to correct the measurements. The values represent
 620         * offsets for the given input from the output on ideal curve.
 621         */
 622        ret = twl_i2c_read(TWL6030_MODULE_ID2, trim_regs,
 623                        TWL6030_GPADC_TRIM1, TWL6030_GPADC_NUM_TRIM_REGS);
 624        if (ret < 0) {
 625                dev_err(gpadc->dev, "calibration failed\n");
 626                return ret;
 627        }
 628
 629        for (chn = 0; chn < TWL6030_GPADC_MAX_CHANNELS; chn++) {
 630
 631                switch (chn) {
 632                case 0:
 633                        d1 = trim_regs[0];
 634                        d2 = trim_regs[1];
 635                        break;
 636                case 1:
 637                case 3:
 638                case 4:
 639                case 5:
 640                case 6:
 641                        d1 = trim_regs[4];
 642                        d2 = trim_regs[5];
 643                        break;
 644                case 2:
 645                        d1 = trim_regs[12];
 646                        d2 = trim_regs[13];
 647                        break;
 648                case 7:
 649                        d1 = trim_regs[6];
 650                        d2 = trim_regs[7];
 651                        break;
 652                case 8:
 653                        d1 = trim_regs[2];
 654                        d2 = trim_regs[3];
 655                        break;
 656                case 9:
 657                        d1 = trim_regs[8];
 658                        d2 = trim_regs[9];
 659                        break;
 660                case 10:
 661                        d1 = trim_regs[10];
 662                        d2 = trim_regs[11];
 663                        break;
 664                case 14:
 665                        d1 = trim_regs[14];
 666                        d2 = trim_regs[15];
 667                        break;
 668                default:
 669                        continue;
 670                }
 671
 672                d1 = twl6030_gpadc_get_trim_offset(d1);
 673                d2 = twl6030_gpadc_get_trim_offset(d2);
 674
 675                twl6030_calibrate_channel(gpadc, chn, d1, d2);
 676        }
 677
 678        return 0;
 679}
 680
 681static int twl6032_get_trim_value(u8 *trim_regs, unsigned int reg0,
 682                unsigned int reg1, unsigned int mask0, unsigned int mask1,
 683                unsigned int shift0)
 684{
 685        int val;
 686
 687        val = (trim_regs[reg0] & mask0) << shift0;
 688        val |= (trim_regs[reg1] & mask1) >> 1;
 689        if (trim_regs[reg1] & 0x01)
 690                val = -val;
 691
 692        return val;
 693}
 694
 695static int twl6032_calibration(struct twl6030_gpadc_data *gpadc)
 696{
 697        int chn, d1 = 0, d2 = 0, temp;
 698        u8 trim_regs[TWL6030_GPADC_NUM_TRIM_REGS];
 699        int ret;
 700
 701        ret = twl_i2c_read(TWL6030_MODULE_ID2, trim_regs,
 702                        TWL6030_GPADC_TRIM1, TWL6030_GPADC_NUM_TRIM_REGS);
 703        if (ret < 0) {
 704                dev_err(gpadc->dev, "calibration failed\n");
 705                return ret;
 706        }
 707
 708        /*
 709         * Loop to calculate the value needed for returning voltages from
 710         * GPADC not values.
 711         *
 712         * gain is calculated to 3 decimal places fixed point.
 713         */
 714        for (chn = 0; chn < TWL6032_GPADC_MAX_CHANNELS; chn++) {
 715
 716                switch (chn) {
 717                case 0:
 718                case 1:
 719                case 2:
 720                case 3:
 721                case 4:
 722                case 5:
 723                case 6:
 724                case 11:
 725                case 14:
 726                        d1 = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
 727                                                                0x06, 2);
 728                        d2 = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
 729                                                                0x06, 2);
 730                        break;
 731                case 8:
 732                        temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
 733                                                                0x06, 2);
 734                        d1 = temp + twl6032_get_trim_value(trim_regs, 7, 6,
 735                                                                0x18, 0x1E, 1);
 736
 737                        temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3F,
 738                                                                0x06, 2);
 739                        d2 = temp + twl6032_get_trim_value(trim_regs, 9, 7,
 740                                                                0x1F, 0x06, 2);
 741                        break;
 742                case 9:
 743                        temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
 744                                                                0x06, 2);
 745                        d1 = temp + twl6032_get_trim_value(trim_regs, 13, 11,
 746                                                                0x18, 0x1E, 1);
 747
 748                        temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
 749                                                                0x06, 2);
 750                        d2 = temp + twl6032_get_trim_value(trim_regs, 15, 13,
 751                                                                0x1F, 0x06, 1);
 752                        break;
 753                case 10:
 754                        d1 = twl6032_get_trim_value(trim_regs, 10, 8, 0x0f,
 755                                                                0x0E, 3);
 756                        d2 = twl6032_get_trim_value(trim_regs, 14, 12, 0x0f,
 757                                                                0x0E, 3);
 758                        break;
 759                case 7:
 760                case 18:
 761                        temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
 762                                                                0x06, 2);
 763
 764                        d1 = (trim_regs[4] & 0x7E) >> 1;
 765                        if (trim_regs[4] & 0x01)
 766                                d1 = -d1;
 767                        d1 += temp;
 768
 769                        temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
 770                                                                0x06, 2);
 771
 772                        d2 = (trim_regs[5] & 0xFE) >> 1;
 773                        if (trim_regs[5] & 0x01)
 774                                d2 = -d2;
 775
 776                        d2 += temp;
 777                        break;
 778                default:
 779                        /* No data for other channels */
 780                        continue;
 781                }
 782
 783                twl6030_calibrate_channel(gpadc, chn, d1, d2);
 784        }
 785
 786        return 0;
 787}
 788
 789#define TWL6030_GPADC_CHAN(chn, _type, chan_info) {     \
 790        .type = _type,                                  \
 791        .channel = chn,                                 \
 792        .info_mask_separate = BIT(chan_info),           \
 793        .indexed = 1,                                   \
 794}
 795
 796static const struct iio_chan_spec twl6030_gpadc_iio_channels[] = {
 797        TWL6030_GPADC_CHAN(0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 798        TWL6030_GPADC_CHAN(1, IIO_TEMP, IIO_CHAN_INFO_RAW),
 799        TWL6030_GPADC_CHAN(2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 800        TWL6030_GPADC_CHAN(3, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 801        TWL6030_GPADC_CHAN(4, IIO_TEMP, IIO_CHAN_INFO_RAW),
 802        TWL6030_GPADC_CHAN(5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 803        TWL6030_GPADC_CHAN(6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 804        TWL6030_GPADC_CHAN(7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 805        TWL6030_GPADC_CHAN(8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 806        TWL6030_GPADC_CHAN(9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 807        TWL6030_GPADC_CHAN(10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 808        TWL6030_GPADC_CHAN(11, IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
 809        TWL6030_GPADC_CHAN(14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 810};
 811
 812static const struct iio_chan_spec twl6032_gpadc_iio_channels[] = {
 813        TWL6030_GPADC_CHAN(0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 814        TWL6030_GPADC_CHAN(1, IIO_TEMP, IIO_CHAN_INFO_RAW),
 815        TWL6030_GPADC_CHAN(2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 816        TWL6030_GPADC_CHAN(3, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 817        TWL6030_GPADC_CHAN(4, IIO_TEMP, IIO_CHAN_INFO_RAW),
 818        TWL6030_GPADC_CHAN(5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 819        TWL6030_GPADC_CHAN(6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 820        TWL6030_GPADC_CHAN(7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 821        TWL6030_GPADC_CHAN(8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 822        TWL6030_GPADC_CHAN(9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 823        TWL6030_GPADC_CHAN(10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 824        TWL6030_GPADC_CHAN(11, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 825        TWL6030_GPADC_CHAN(14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 826        TWL6030_GPADC_CHAN(17, IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
 827        TWL6030_GPADC_CHAN(18, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 828};
 829
 830static const struct iio_info twl6030_gpadc_iio_info = {
 831        .read_raw = &twl6030_gpadc_read_raw,
 832};
 833
 834static const struct twl6030_gpadc_platform_data twl6030_pdata = {
 835        .iio_channels = twl6030_gpadc_iio_channels,
 836        .nchannels = TWL6030_GPADC_USED_CHANNELS,
 837        .ideal = twl6030_ideal,
 838        .start_conversion = twl6030_start_conversion,
 839        .channel_to_reg = twl6030_channel_to_reg,
 840        .calibrate = twl6030_calibration,
 841};
 842
 843static const struct twl6030_gpadc_platform_data twl6032_pdata = {
 844        .iio_channels = twl6032_gpadc_iio_channels,
 845        .nchannels = TWL6032_GPADC_USED_CHANNELS,
 846        .ideal = twl6032_ideal,
 847        .start_conversion = twl6032_start_conversion,
 848        .channel_to_reg = twl6032_channel_to_reg,
 849        .calibrate = twl6032_calibration,
 850};
 851
 852static const struct of_device_id of_twl6030_match_tbl[] = {
 853        {
 854                .compatible = "ti,twl6030-gpadc",
 855                .data = &twl6030_pdata,
 856        },
 857        {
 858                .compatible = "ti,twl6032-gpadc",
 859                .data = &twl6032_pdata,
 860        },
 861        { /* end */ }
 862};
 863MODULE_DEVICE_TABLE(of, of_twl6030_match_tbl);
 864
 865static int twl6030_gpadc_probe(struct platform_device *pdev)
 866{
 867        struct device *dev = &pdev->dev;
 868        struct twl6030_gpadc_data *gpadc;
 869        const struct twl6030_gpadc_platform_data *pdata;
 870        const struct of_device_id *match;
 871        struct iio_dev *indio_dev;
 872        int irq;
 873        int ret;
 874
 875        match = of_match_device(of_twl6030_match_tbl, dev);
 876        if (!match)
 877                return -EINVAL;
 878
 879        pdata = match->data;
 880
 881        indio_dev = devm_iio_device_alloc(dev, sizeof(*gpadc));
 882        if (!indio_dev)
 883                return -ENOMEM;
 884
 885        gpadc = iio_priv(indio_dev);
 886
 887        gpadc->twl6030_cal_tbl = devm_kcalloc(dev,
 888                                        pdata->nchannels,
 889                                        sizeof(*gpadc->twl6030_cal_tbl),
 890                                        GFP_KERNEL);
 891        if (!gpadc->twl6030_cal_tbl)
 892                return -ENOMEM;
 893
 894        gpadc->dev = dev;
 895        gpadc->pdata = pdata;
 896
 897        platform_set_drvdata(pdev, indio_dev);
 898        mutex_init(&gpadc->lock);
 899        init_completion(&gpadc->irq_complete);
 900
 901        ret = pdata->calibrate(gpadc);
 902        if (ret < 0) {
 903                dev_err(&pdev->dev, "failed to read calibration registers\n");
 904                return ret;
 905        }
 906
 907        irq = platform_get_irq(pdev, 0);
 908        if (irq < 0)
 909                return irq;
 910
 911        ret = devm_request_threaded_irq(dev, irq, NULL,
 912                                twl6030_gpadc_irq_handler,
 913                                IRQF_ONESHOT, "twl6030_gpadc", indio_dev);
 914
 915        ret = twl6030_gpadc_enable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK);
 916        if (ret < 0) {
 917                dev_err(&pdev->dev, "failed to enable GPADC interrupt\n");
 918                return ret;
 919        }
 920
 921        ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS,
 922                                        TWL6030_REG_TOGGLE1);
 923        if (ret < 0) {
 924                dev_err(&pdev->dev, "failed to enable GPADC module\n");
 925                return ret;
 926        }
 927
 928        indio_dev->name = DRIVER_NAME;
 929        indio_dev->info = &twl6030_gpadc_iio_info;
 930        indio_dev->modes = INDIO_DIRECT_MODE;
 931        indio_dev->channels = pdata->iio_channels;
 932        indio_dev->num_channels = pdata->nchannels;
 933
 934        return iio_device_register(indio_dev);
 935}
 936
 937static int twl6030_gpadc_remove(struct platform_device *pdev)
 938{
 939        struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 940
 941        twl6030_gpadc_disable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK);
 942        iio_device_unregister(indio_dev);
 943
 944        return 0;
 945}
 946
 947#ifdef CONFIG_PM_SLEEP
 948static int twl6030_gpadc_suspend(struct device *pdev)
 949{
 950        int ret;
 951
 952        ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCR,
 953                                TWL6030_REG_TOGGLE1);
 954        if (ret)
 955                dev_err(pdev, "error resetting GPADC (%d)!\n", ret);
 956
 957        return 0;
 958};
 959
 960static int twl6030_gpadc_resume(struct device *pdev)
 961{
 962        int ret;
 963
 964        ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS,
 965                                TWL6030_REG_TOGGLE1);
 966        if (ret)
 967                dev_err(pdev, "error setting GPADC (%d)!\n", ret);
 968
 969        return 0;
 970};
 971#endif
 972
 973static SIMPLE_DEV_PM_OPS(twl6030_gpadc_pm_ops, twl6030_gpadc_suspend,
 974                                        twl6030_gpadc_resume);
 975
 976static struct platform_driver twl6030_gpadc_driver = {
 977        .probe          = twl6030_gpadc_probe,
 978        .remove         = twl6030_gpadc_remove,
 979        .driver         = {
 980                .name   = DRIVER_NAME,
 981                .pm     = &twl6030_gpadc_pm_ops,
 982                .of_match_table = of_twl6030_match_tbl,
 983        },
 984};
 985
 986module_platform_driver(twl6030_gpadc_driver);
 987
 988MODULE_ALIAS("platform:" DRIVER_NAME);
 989MODULE_AUTHOR("Balaji T K <balajitk@ti.com>");
 990MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
 991MODULE_AUTHOR("Oleksandr Kozaruk <oleksandr.kozaruk@ti.com");
 992MODULE_DESCRIPTION("twl6030 ADC driver");
 993MODULE_LICENSE("GPL");
 994