linux/drivers/iio/adc/da9150-gpadc.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * DA9150 GPADC Driver
   4 *
   5 * Copyright (c) 2014 Dialog Semiconductor
   6 *
   7 * Author: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
   8 */
   9
  10#include <linux/kernel.h>
  11#include <linux/slab.h>
  12#include <linux/module.h>
  13#include <linux/platform_device.h>
  14#include <linux/interrupt.h>
  15#include <linux/mutex.h>
  16#include <linux/completion.h>
  17#include <linux/iio/iio.h>
  18#include <linux/iio/machine.h>
  19#include <linux/iio/driver.h>
  20#include <linux/mfd/da9150/core.h>
  21#include <linux/mfd/da9150/registers.h>
  22
  23/* Channels */
  24enum da9150_gpadc_hw_channel {
  25        DA9150_GPADC_HW_CHAN_GPIOA_2V = 0,
  26        DA9150_GPADC_HW_CHAN_GPIOA_2V_,
  27        DA9150_GPADC_HW_CHAN_GPIOB_2V,
  28        DA9150_GPADC_HW_CHAN_GPIOB_2V_,
  29        DA9150_GPADC_HW_CHAN_GPIOC_2V,
  30        DA9150_GPADC_HW_CHAN_GPIOC_2V_,
  31        DA9150_GPADC_HW_CHAN_GPIOD_2V,
  32        DA9150_GPADC_HW_CHAN_GPIOD_2V_,
  33        DA9150_GPADC_HW_CHAN_IBUS_SENSE,
  34        DA9150_GPADC_HW_CHAN_IBUS_SENSE_,
  35        DA9150_GPADC_HW_CHAN_VBUS_DIV,
  36        DA9150_GPADC_HW_CHAN_VBUS_DIV_,
  37        DA9150_GPADC_HW_CHAN_ID,
  38        DA9150_GPADC_HW_CHAN_ID_,
  39        DA9150_GPADC_HW_CHAN_VSYS,
  40        DA9150_GPADC_HW_CHAN_VSYS_,
  41        DA9150_GPADC_HW_CHAN_GPIOA_6V,
  42        DA9150_GPADC_HW_CHAN_GPIOA_6V_,
  43        DA9150_GPADC_HW_CHAN_GPIOB_6V,
  44        DA9150_GPADC_HW_CHAN_GPIOB_6V_,
  45        DA9150_GPADC_HW_CHAN_GPIOC_6V,
  46        DA9150_GPADC_HW_CHAN_GPIOC_6V_,
  47        DA9150_GPADC_HW_CHAN_GPIOD_6V,
  48        DA9150_GPADC_HW_CHAN_GPIOD_6V_,
  49        DA9150_GPADC_HW_CHAN_VBAT,
  50        DA9150_GPADC_HW_CHAN_VBAT_,
  51        DA9150_GPADC_HW_CHAN_TBAT,
  52        DA9150_GPADC_HW_CHAN_TBAT_,
  53        DA9150_GPADC_HW_CHAN_TJUNC_CORE,
  54        DA9150_GPADC_HW_CHAN_TJUNC_CORE_,
  55        DA9150_GPADC_HW_CHAN_TJUNC_OVP,
  56        DA9150_GPADC_HW_CHAN_TJUNC_OVP_,
  57};
  58
  59enum da9150_gpadc_channel {
  60        DA9150_GPADC_CHAN_GPIOA = 0,
  61        DA9150_GPADC_CHAN_GPIOB,
  62        DA9150_GPADC_CHAN_GPIOC,
  63        DA9150_GPADC_CHAN_GPIOD,
  64        DA9150_GPADC_CHAN_IBUS,
  65        DA9150_GPADC_CHAN_VBUS,
  66        DA9150_GPADC_CHAN_VSYS,
  67        DA9150_GPADC_CHAN_VBAT,
  68        DA9150_GPADC_CHAN_TBAT,
  69        DA9150_GPADC_CHAN_TJUNC_CORE,
  70        DA9150_GPADC_CHAN_TJUNC_OVP,
  71};
  72
  73/* Private data */
  74struct da9150_gpadc {
  75        struct da9150 *da9150;
  76        struct device *dev;
  77
  78        struct mutex lock;
  79        struct completion complete;
  80};
  81
  82
  83static irqreturn_t da9150_gpadc_irq(int irq, void *data)
  84{
  85
  86        struct da9150_gpadc *gpadc = data;
  87
  88        complete(&gpadc->complete);
  89
  90        return IRQ_HANDLED;
  91}
  92
  93static int da9150_gpadc_read_adc(struct da9150_gpadc *gpadc, int hw_chan)
  94{
  95        u8 result_regs[2];
  96        int result;
  97
  98        mutex_lock(&gpadc->lock);
  99
 100        /* Set channel & enable measurement */
 101        da9150_reg_write(gpadc->da9150, DA9150_GPADC_MAN,
 102                         (DA9150_GPADC_EN_MASK |
 103                          hw_chan << DA9150_GPADC_MUX_SHIFT));
 104
 105        /* Consume left-over completion from a previous timeout */
 106        try_wait_for_completion(&gpadc->complete);
 107
 108        /* Check for actual completion */
 109        wait_for_completion_timeout(&gpadc->complete, msecs_to_jiffies(5));
 110
 111        /* Read result and status from device */
 112        da9150_bulk_read(gpadc->da9150, DA9150_GPADC_RES_A, 2, result_regs);
 113
 114        mutex_unlock(&gpadc->lock);
 115
 116        /* Check to make sure device really has completed reading */
 117        if (result_regs[1] & DA9150_GPADC_RUN_MASK) {
 118                dev_err(gpadc->dev, "Timeout on channel %d of GPADC\n",
 119                        hw_chan);
 120                return -ETIMEDOUT;
 121        }
 122
 123        /* LSBs - 2 bits */
 124        result = (result_regs[1] & DA9150_GPADC_RES_L_MASK) >>
 125                 DA9150_GPADC_RES_L_SHIFT;
 126        /* MSBs - 8 bits */
 127        result |= result_regs[0] << DA9150_GPADC_RES_L_BITS;
 128
 129        return result;
 130}
 131
 132static inline int da9150_gpadc_gpio_6v_voltage_now(int raw_val)
 133{
 134        /* Convert to mV */
 135        return (6 * ((raw_val * 1000) + 500)) / 1024;
 136}
 137
 138static inline int da9150_gpadc_ibus_current_avg(int raw_val)
 139{
 140        /* Convert to mA */
 141        return (4 * ((raw_val * 1000) + 500)) / 2048;
 142}
 143
 144static inline int da9150_gpadc_vbus_21v_voltage_now(int raw_val)
 145{
 146        /* Convert to mV */
 147        return (21 * ((raw_val * 1000) + 500)) / 1024;
 148}
 149
 150static inline int da9150_gpadc_vsys_6v_voltage_now(int raw_val)
 151{
 152        /* Convert to mV */
 153        return (3 * ((raw_val * 1000) + 500)) / 512;
 154}
 155
 156static int da9150_gpadc_read_processed(struct da9150_gpadc *gpadc, int channel,
 157                                       int hw_chan, int *val)
 158{
 159        int raw_val;
 160
 161        raw_val = da9150_gpadc_read_adc(gpadc, hw_chan);
 162        if (raw_val < 0)
 163                return raw_val;
 164
 165        switch (channel) {
 166        case DA9150_GPADC_CHAN_GPIOA:
 167        case DA9150_GPADC_CHAN_GPIOB:
 168        case DA9150_GPADC_CHAN_GPIOC:
 169        case DA9150_GPADC_CHAN_GPIOD:
 170                *val = da9150_gpadc_gpio_6v_voltage_now(raw_val);
 171                break;
 172        case DA9150_GPADC_CHAN_IBUS:
 173                *val = da9150_gpadc_ibus_current_avg(raw_val);
 174                break;
 175        case DA9150_GPADC_CHAN_VBUS:
 176                *val = da9150_gpadc_vbus_21v_voltage_now(raw_val);
 177                break;
 178        case DA9150_GPADC_CHAN_VSYS:
 179                *val = da9150_gpadc_vsys_6v_voltage_now(raw_val);
 180                break;
 181        default:
 182                /* No processing for other channels so return raw value */
 183                *val = raw_val;
 184                break;
 185        }
 186
 187        return IIO_VAL_INT;
 188}
 189
 190static int da9150_gpadc_read_scale(int channel, int *val, int *val2)
 191{
 192        switch (channel) {
 193        case DA9150_GPADC_CHAN_VBAT:
 194                *val = 2932;
 195                *val2 = 1000;
 196                return IIO_VAL_FRACTIONAL;
 197        case DA9150_GPADC_CHAN_TJUNC_CORE:
 198        case DA9150_GPADC_CHAN_TJUNC_OVP:
 199                *val = 1000000;
 200                *val2 = 4420;
 201                return IIO_VAL_FRACTIONAL;
 202        default:
 203                return -EINVAL;
 204        }
 205}
 206
 207static int da9150_gpadc_read_offset(int channel, int *val)
 208{
 209        switch (channel) {
 210        case DA9150_GPADC_CHAN_VBAT:
 211                *val = 1500000 / 2932;
 212                return IIO_VAL_INT;
 213        case DA9150_GPADC_CHAN_TJUNC_CORE:
 214        case DA9150_GPADC_CHAN_TJUNC_OVP:
 215                *val = -144;
 216                return IIO_VAL_INT;
 217        default:
 218                return -EINVAL;
 219        }
 220}
 221
 222static int da9150_gpadc_read_raw(struct iio_dev *indio_dev,
 223                                 struct iio_chan_spec const *chan,
 224                                 int *val, int *val2, long mask)
 225{
 226        struct da9150_gpadc *gpadc = iio_priv(indio_dev);
 227
 228        if ((chan->channel < DA9150_GPADC_CHAN_GPIOA) ||
 229            (chan->channel > DA9150_GPADC_CHAN_TJUNC_OVP))
 230                return -EINVAL;
 231
 232        switch (mask) {
 233        case IIO_CHAN_INFO_RAW:
 234        case IIO_CHAN_INFO_PROCESSED:
 235                return da9150_gpadc_read_processed(gpadc, chan->channel,
 236                                                   chan->address, val);
 237        case IIO_CHAN_INFO_SCALE:
 238                return da9150_gpadc_read_scale(chan->channel, val, val2);
 239        case IIO_CHAN_INFO_OFFSET:
 240                return da9150_gpadc_read_offset(chan->channel, val);
 241        default:
 242                return -EINVAL;
 243        }
 244}
 245
 246static const struct iio_info da9150_gpadc_info = {
 247        .read_raw = &da9150_gpadc_read_raw,
 248};
 249
 250#define DA9150_GPADC_CHANNEL(_id, _hw_id, _type, chan_info,     \
 251                             _ext_name) {                       \
 252        .type = _type,                                          \
 253        .indexed = 1,                                           \
 254        .channel = DA9150_GPADC_CHAN_##_id,                     \
 255        .address = DA9150_GPADC_HW_CHAN_##_hw_id,               \
 256        .info_mask_separate = chan_info,                        \
 257        .extend_name = _ext_name,                               \
 258        .datasheet_name = #_id,                                 \
 259}
 260
 261#define DA9150_GPADC_CHANNEL_RAW(_id, _hw_id, _type, _ext_name) \
 262        DA9150_GPADC_CHANNEL(_id, _hw_id, _type,                \
 263                             BIT(IIO_CHAN_INFO_RAW), _ext_name)
 264
 265#define DA9150_GPADC_CHANNEL_SCALED(_id, _hw_id, _type, _ext_name)      \
 266        DA9150_GPADC_CHANNEL(_id, _hw_id, _type,                        \
 267                             BIT(IIO_CHAN_INFO_RAW) |                   \
 268                             BIT(IIO_CHAN_INFO_SCALE) |                 \
 269                             BIT(IIO_CHAN_INFO_OFFSET),                 \
 270                             _ext_name)
 271
 272#define DA9150_GPADC_CHANNEL_PROCESSED(_id, _hw_id, _type, _ext_name)   \
 273        DA9150_GPADC_CHANNEL(_id, _hw_id, _type,                        \
 274                             BIT(IIO_CHAN_INFO_PROCESSED), _ext_name)
 275
 276/* Supported channels */
 277static const struct iio_chan_spec da9150_gpadc_channels[] = {
 278        DA9150_GPADC_CHANNEL_PROCESSED(GPIOA, GPIOA_6V, IIO_VOLTAGE, NULL),
 279        DA9150_GPADC_CHANNEL_PROCESSED(GPIOB, GPIOB_6V, IIO_VOLTAGE, NULL),
 280        DA9150_GPADC_CHANNEL_PROCESSED(GPIOC, GPIOC_6V, IIO_VOLTAGE, NULL),
 281        DA9150_GPADC_CHANNEL_PROCESSED(GPIOD, GPIOD_6V, IIO_VOLTAGE, NULL),
 282        DA9150_GPADC_CHANNEL_PROCESSED(IBUS, IBUS_SENSE, IIO_CURRENT, "ibus"),
 283        DA9150_GPADC_CHANNEL_PROCESSED(VBUS, VBUS_DIV_, IIO_VOLTAGE, "vbus"),
 284        DA9150_GPADC_CHANNEL_PROCESSED(VSYS, VSYS, IIO_VOLTAGE, "vsys"),
 285        DA9150_GPADC_CHANNEL_SCALED(VBAT, VBAT, IIO_VOLTAGE, "vbat"),
 286        DA9150_GPADC_CHANNEL_RAW(TBAT, TBAT, IIO_VOLTAGE, "tbat"),
 287        DA9150_GPADC_CHANNEL_SCALED(TJUNC_CORE, TJUNC_CORE, IIO_TEMP,
 288                                    "tjunc_core"),
 289        DA9150_GPADC_CHANNEL_SCALED(TJUNC_OVP, TJUNC_OVP, IIO_TEMP,
 290                                    "tjunc_ovp"),
 291};
 292
 293/* Default maps used by da9150-charger */
 294static struct iio_map da9150_gpadc_default_maps[] = {
 295        {
 296                .consumer_dev_name = "da9150-charger",
 297                .consumer_channel = "CHAN_IBUS",
 298                .adc_channel_label = "IBUS",
 299        },
 300        {
 301                .consumer_dev_name = "da9150-charger",
 302                .consumer_channel = "CHAN_VBUS",
 303                .adc_channel_label = "VBUS",
 304        },
 305        {
 306                .consumer_dev_name = "da9150-charger",
 307                .consumer_channel = "CHAN_TJUNC",
 308                .adc_channel_label = "TJUNC_CORE",
 309        },
 310        {
 311                .consumer_dev_name = "da9150-charger",
 312                .consumer_channel = "CHAN_VBAT",
 313                .adc_channel_label = "VBAT",
 314        },
 315        {},
 316};
 317
 318static int da9150_gpadc_probe(struct platform_device *pdev)
 319{
 320        struct device *dev = &pdev->dev;
 321        struct da9150 *da9150 = dev_get_drvdata(dev->parent);
 322        struct da9150_gpadc *gpadc;
 323        struct iio_dev *indio_dev;
 324        int irq, ret;
 325
 326        indio_dev = devm_iio_device_alloc(dev, sizeof(*gpadc));
 327        if (!indio_dev) {
 328                dev_err(&pdev->dev, "Failed to allocate IIO device\n");
 329                return -ENOMEM;
 330        }
 331        gpadc = iio_priv(indio_dev);
 332
 333        platform_set_drvdata(pdev, indio_dev);
 334        gpadc->da9150 = da9150;
 335        gpadc->dev = dev;
 336        mutex_init(&gpadc->lock);
 337        init_completion(&gpadc->complete);
 338
 339        irq = platform_get_irq_byname(pdev, "GPADC");
 340        if (irq < 0)
 341                return irq;
 342
 343        ret = devm_request_threaded_irq(dev, irq, NULL, da9150_gpadc_irq,
 344                                        IRQF_ONESHOT, "GPADC", gpadc);
 345        if (ret) {
 346                dev_err(dev, "Failed to request IRQ %d: %d\n", irq, ret);
 347                return ret;
 348        }
 349
 350        ret = iio_map_array_register(indio_dev, da9150_gpadc_default_maps);
 351        if (ret) {
 352                dev_err(dev, "Failed to register IIO maps: %d\n", ret);
 353                return ret;
 354        }
 355
 356        indio_dev->name = dev_name(dev);
 357        indio_dev->info = &da9150_gpadc_info;
 358        indio_dev->modes = INDIO_DIRECT_MODE;
 359        indio_dev->channels = da9150_gpadc_channels;
 360        indio_dev->num_channels = ARRAY_SIZE(da9150_gpadc_channels);
 361
 362        ret = iio_device_register(indio_dev);
 363        if (ret) {
 364                dev_err(dev, "Failed to register IIO device: %d\n", ret);
 365                goto iio_map_unreg;
 366        }
 367
 368        return 0;
 369
 370iio_map_unreg:
 371        iio_map_array_unregister(indio_dev);
 372
 373        return ret;
 374}
 375
 376static int da9150_gpadc_remove(struct platform_device *pdev)
 377{
 378        struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 379
 380        iio_device_unregister(indio_dev);
 381        iio_map_array_unregister(indio_dev);
 382
 383        return 0;
 384}
 385
 386static struct platform_driver da9150_gpadc_driver = {
 387        .driver = {
 388                .name = "da9150-gpadc",
 389        },
 390        .probe = da9150_gpadc_probe,
 391        .remove = da9150_gpadc_remove,
 392};
 393
 394module_platform_driver(da9150_gpadc_driver);
 395
 396MODULE_DESCRIPTION("GPADC Driver for DA9150");
 397MODULE_AUTHOR("Adam Thomson <Adam.Thomson.Opensource@diasemi.com>");
 398MODULE_LICENSE("GPL");
 399