drivers/input/touchscreen/tsc2007_iio.c

   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
  11 struct 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
  25 static 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
  37 static 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
 102 static const struct iio_info tsc2007_iio_info = {
 103         .read_raw = tsc2007_read_raw,
 104 };
 105
 106 int 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 }