LXR linux/drivers/input/touchscreen/tsc2007

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (c) 2016 Golden Delicious Comp. GmbH&Co. KG
   4 *      Nikolaus Schaller <hns@goldelico.com>
   5 */
   6
   7#include <linux/i2c.h>
   8#include <linux/iio/iio.h>
   9#include "tsc2007.h"
  10
  11struct tsc2007_iio {
  12        struct tsc2007 *ts;
  13};
  14
  15#define TSC2007_CHAN_IIO(_chan, _name, _type, _chan_info) \
  16{ \
  17        .datasheet_name = _name, \
  18        .type = _type, \
  19        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |  \
  20                        BIT(_chan_info), \
  21        .indexed = 1, \
  22        .channel = _chan, \
  23}
  24
  25static const struct iio_chan_spec tsc2007_iio_channel[] = {
  26        TSC2007_CHAN_IIO(0, "x", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
  27        TSC2007_CHAN_IIO(1, "y", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
  28        TSC2007_CHAN_IIO(2, "z1", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
  29        TSC2007_CHAN_IIO(3, "z2", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
  30        TSC2007_CHAN_IIO(4, "adc", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
  31        TSC2007_CHAN_IIO(5, "rt", IIO_VOLTAGE, IIO_CHAN_INFO_RAW), /* Ohms? */
  32        TSC2007_CHAN_IIO(6, "pen", IIO_PRESSURE, IIO_CHAN_INFO_RAW),
  33        TSC2007_CHAN_IIO(7, "temp0", IIO_TEMP, IIO_CHAN_INFO_RAW),
  34        TSC2007_CHAN_IIO(8, "temp1", IIO_TEMP, IIO_CHAN_INFO_RAW),
  35};
  36
  37static int tsc2007_read_raw(struct iio_dev *indio_dev,
  38                            struct iio_chan_spec const *chan,
  39                            int *val, int *val2, long mask)
  40{
  41        struct tsc2007_iio *iio = iio_priv(indio_dev);
  42        struct tsc2007 *tsc = iio->ts;
  43        int adc_chan = chan->channel;
  44        int ret = 0;
  45
  46        if (adc_chan >= ARRAY_SIZE(tsc2007_iio_channel))
  47                return -EINVAL;
  48
  49        if (mask != IIO_CHAN_INFO_RAW)
  50                return -EINVAL;
  51
  52        mutex_lock(&tsc->mlock);
  53
  54        switch (chan->channel) {
  55        case 0:
  56                *val = tsc2007_xfer(tsc, READ_X);
  57                break;
  58        case 1:
  59                *val = tsc2007_xfer(tsc, READ_Y);
  60                break;
  61        case 2:
  62                *val = tsc2007_xfer(tsc, READ_Z1);
  63                break;
  64        case 3:
  65                *val = tsc2007_xfer(tsc, READ_Z2);
  66                break;
  67        case 4:
  68                *val = tsc2007_xfer(tsc, (ADC_ON_12BIT | TSC2007_MEASURE_AUX));
  69                break;
  70        case 5: {
  71                struct ts_event tc;
  72
  73                tc.x = tsc2007_xfer(tsc, READ_X);
  74                tc.z1 = tsc2007_xfer(tsc, READ_Z1);
  75                tc.z2 = tsc2007_xfer(tsc, READ_Z2);
  76                *val = tsc2007_calculate_resistance(tsc, &tc);
  77                break;
  78        }
  79        case 6:
  80                *val = tsc2007_is_pen_down(tsc);
  81                break;
  82        case 7:
  83                *val = tsc2007_xfer(tsc,
  84                                    (ADC_ON_12BIT | TSC2007_MEASURE_TEMP0));
  85                break;
  86        case 8:
  87                *val = tsc2007_xfer(tsc,
  88                                    (ADC_ON_12BIT | TSC2007_MEASURE_TEMP1));
  89                break;
  90        }
  91
  92        /* Prepare for next touch reading - power down ADC, enable PENIRQ */
  93        tsc2007_xfer(tsc, PWRDOWN);
  94
  95        mutex_unlock(&tsc->mlock);
  96
  97        ret = IIO_VAL_INT;
  98
  99        return ret;
 100}
 101
 102static const struct iio_info tsc2007_iio_info = {
 103        .read_raw = tsc2007_read_raw,
 104};
 105
 106int tsc2007_iio_configure(struct tsc2007 *ts)
 107{
 108        struct iio_dev *indio_dev;
 109        struct tsc2007_iio *iio;
 110        int error;
 111
 112        indio_dev = devm_iio_device_alloc(&ts->client->dev, sizeof(*iio));
 113        if (!indio_dev) {
 114                dev_err(&ts->client->dev, "iio_device_alloc failed\n");
 115                return -ENOMEM;
 116        }
 117
 118        iio = iio_priv(indio_dev);
 119        iio->ts = ts;
 120
 121        indio_dev->name = "tsc2007";
 122        indio_dev->info = &tsc2007_iio_info;
 123        indio_dev->modes = INDIO_DIRECT_MODE;
 124        indio_dev->channels = tsc2007_iio_channel;
 125        indio_dev->num_channels = ARRAY_SIZE(tsc2007_iio_channel);
 126
 127        error = devm_iio_device_register(&ts->client->dev, indio_dev);
 128        if (error) {
 129                dev_err(&ts->client->dev,
 130                        "iio_device_register() failed: %d\n", error);
 131                return error;
 132        }
 133
 134        return 0;
 135}
 136