LXR linux/drivers/input/touchscreen/tsc2007

   1/*
   2 * Copyright (c) 2016 Golden Delicious Comp. GmbH&Co. KG
   3 *      Nikolaus Schaller <hns@goldelico.com>
   4 *
   5 *  This program is free software; you can redistribute it and/or modify
   6 *  it under the terms of the GNU General Public License version 2 as
   7 *  published by the Free Software Foundation.
   8 */
   9
  10#include <linux/i2c.h>
  11#include <linux/iio/iio.h>
  12#include "tsc2007.h"
  13
  14struct tsc2007_iio {
  15        struct tsc2007 *ts;
  16};
  17
  18#define TSC2007_CHAN_IIO(_chan, _name, _type, _chan_info) \
  19{ \
  20        .datasheet_name = _name, \
  21        .type = _type, \
  22        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |  \
  23                        BIT(_chan_info), \
  24        .indexed = 1, \
  25        .channel = _chan, \
  26}
  27
  28static const struct iio_chan_spec tsc2007_iio_channel[] = {
  29        TSC2007_CHAN_IIO(0, "x", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
  30        TSC2007_CHAN_IIO(1, "y", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
  31        TSC2007_CHAN_IIO(2, "z1", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
  32        TSC2007_CHAN_IIO(3, "z2", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
  33        TSC2007_CHAN_IIO(4, "adc", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
  34        TSC2007_CHAN_IIO(5, "rt", IIO_VOLTAGE, IIO_CHAN_INFO_RAW), /* Ohms? */
  35        TSC2007_CHAN_IIO(6, "pen", IIO_PRESSURE, IIO_CHAN_INFO_RAW),
  36        TSC2007_CHAN_IIO(7, "temp0", IIO_TEMP, IIO_CHAN_INFO_RAW),
  37        TSC2007_CHAN_IIO(8, "temp1", IIO_TEMP, IIO_CHAN_INFO_RAW),
  38};
  39
  40static int tsc2007_read_raw(struct iio_dev *indio_dev,
  41                            struct iio_chan_spec const *chan,
  42                            int *val, int *val2, long mask)
  43{
  44        struct tsc2007_iio *iio = iio_priv(indio_dev);
  45        struct tsc2007 *tsc = iio->ts;
  46        int adc_chan = chan->channel;
  47        int ret = 0;
  48
  49        if (adc_chan >= ARRAY_SIZE(tsc2007_iio_channel))
  50                return -EINVAL;
  51
  52        if (mask != IIO_CHAN_INFO_RAW)
  53                return -EINVAL;
  54
  55        mutex_lock(&tsc->mlock);
  56
  57        switch (chan->channel) {
  58        case 0:
  59                *val = tsc2007_xfer(tsc, READ_X);
  60                break;
  61        case 1:
  62                *val = tsc2007_xfer(tsc, READ_Y);
  63                break;
  64        case 2:
  65                *val = tsc2007_xfer(tsc, READ_Z1);
  66                break;
  67        case 3:
  68                *val = tsc2007_xfer(tsc, READ_Z2);
  69                break;
  70        case 4:
  71                *val = tsc2007_xfer(tsc, (ADC_ON_12BIT | TSC2007_MEASURE_AUX));
  72                break;
  73        case 5: {
  74                struct ts_event tc;
  75
  76                tc.x = tsc2007_xfer(tsc, READ_X);
  77                tc.z1 = tsc2007_xfer(tsc, READ_Z1);
  78                tc.z2 = tsc2007_xfer(tsc, READ_Z2);
  79                *val = tsc2007_calculate_resistance(tsc, &tc);
  80                break;
  81        }
  82        case 6:
  83                *val = tsc2007_is_pen_down(tsc);
  84                break;
  85        case 7:
  86                *val = tsc2007_xfer(tsc,
  87                                    (ADC_ON_12BIT | TSC2007_MEASURE_TEMP0));
  88                break;
  89        case 8:
  90                *val = tsc2007_xfer(tsc,
  91                                    (ADC_ON_12BIT | TSC2007_MEASURE_TEMP1));
  92                break;
  93        }
  94
  95        /* Prepare for next touch reading - power down ADC, enable PENIRQ */
  96        tsc2007_xfer(tsc, PWRDOWN);
  97
  98        mutex_unlock(&tsc->mlock);
  99
 100        ret = IIO_VAL_INT;
 101
 102        return ret;
 103}
 104
 105static const struct iio_info tsc2007_iio_info = {
 106        .read_raw = tsc2007_read_raw,
 107};
 108
 109int tsc2007_iio_configure(struct tsc2007 *ts)
 110{
 111        struct iio_dev *indio_dev;
 112        struct tsc2007_iio *iio;
 113        int error;
 114
 115        indio_dev = devm_iio_device_alloc(&ts->client->dev, sizeof(*iio));
 116        if (!indio_dev) {
 117                dev_err(&ts->client->dev, "iio_device_alloc failed\n");
 118                return -ENOMEM;
 119        }
 120
 121        iio = iio_priv(indio_dev);
 122        iio->ts = ts;
 123
 124        indio_dev->name = "tsc2007";
 125        indio_dev->dev.parent = &ts->client->dev;
 126        indio_dev->info = &tsc2007_iio_info;
 127        indio_dev->modes = INDIO_DIRECT_MODE;
 128        indio_dev->channels = tsc2007_iio_channel;
 129        indio_dev->num_channels = ARRAY_SIZE(tsc2007_iio_channel);
 130
 131        error = devm_iio_device_register(&ts->client->dev, indio_dev);
 132        if (error) {
 133                dev_err(&ts->client->dev,
 134                        "iio_device_register() failed: %d\n", error);
 135                return error;
 136        }
 137
 138        return 0;
 139}
 140