input/touchscreen/tsc2007_iio.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Copyright (c) 2016 Golden Delicious Comp. GmbH&Co. KG
0004  *  Nikolaus Schaller <hns@goldelico.com>
0005  */
0006
0007 #include <linux/i2c.h>
0008 #include <linux/iio/iio.h>
0009 #include "tsc2007.h"
0010
0011 struct tsc2007_iio {
0012     struct tsc2007 *ts;
0013 };
0014
0015 #define TSC2007_CHAN_IIO(_chan, _name, _type, _chan_info) \
0016 { \
0017     .datasheet_name = _name, \
0018     .type = _type, \
0019     .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |  \
0020             BIT(_chan_info), \
0021     .indexed = 1, \
0022     .channel = _chan, \
0023 }
0024
0025 static const struct iio_chan_spec tsc2007_iio_channel[] = {
0026     TSC2007_CHAN_IIO(0, "x", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
0027     TSC2007_CHAN_IIO(1, "y", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
0028     TSC2007_CHAN_IIO(2, "z1", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
0029     TSC2007_CHAN_IIO(3, "z2", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
0030     TSC2007_CHAN_IIO(4, "adc", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
0031     TSC2007_CHAN_IIO(5, "rt", IIO_VOLTAGE, IIO_CHAN_INFO_RAW), /* Ohms? */
0032     TSC2007_CHAN_IIO(6, "pen", IIO_PRESSURE, IIO_CHAN_INFO_RAW),
0033     TSC2007_CHAN_IIO(7, "temp0", IIO_TEMP, IIO_CHAN_INFO_RAW),
0034     TSC2007_CHAN_IIO(8, "temp1", IIO_TEMP, IIO_CHAN_INFO_RAW),
0035 };
0036
0037 static int tsc2007_read_raw(struct iio_dev *indio_dev,
0038                 struct iio_chan_spec const *chan,
0039                 int *val, int *val2, long mask)
0040 {
0041     struct tsc2007_iio *iio = iio_priv(indio_dev);
0042     struct tsc2007 *tsc = iio->ts;
0043     int adc_chan = chan->channel;
0044     int ret = 0;
0045
0046     if (adc_chan >= ARRAY_SIZE(tsc2007_iio_channel))
0047         return -EINVAL;
0048
0049     if (mask != IIO_CHAN_INFO_RAW)
0050         return -EINVAL;
0051
0052     mutex_lock(&tsc->mlock);
0053
0054     switch (chan->channel) {
0055     case 0:
0056         *val = tsc2007_xfer(tsc, READ_X);
0057         break;
0058     case 1:
0059         *val = tsc2007_xfer(tsc, READ_Y);
0060         break;
0061     case 2:
0062         *val = tsc2007_xfer(tsc, READ_Z1);
0063         break;
0064     case 3:
0065         *val = tsc2007_xfer(tsc, READ_Z2);
0066         break;
0067     case 4:
0068         *val = tsc2007_xfer(tsc, (ADC_ON_12BIT | TSC2007_MEASURE_AUX));
0069         break;
0070     case 5: {
0071         struct ts_event tc;
0072
0073         tc.x = tsc2007_xfer(tsc, READ_X);
0074         tc.z1 = tsc2007_xfer(tsc, READ_Z1);
0075         tc.z2 = tsc2007_xfer(tsc, READ_Z2);
0076         *val = tsc2007_calculate_resistance(tsc, &tc);
0077         break;
0078     }
0079     case 6:
0080         *val = tsc2007_is_pen_down(tsc);
0081         break;
0082     case 7:
0083         *val = tsc2007_xfer(tsc,
0084                     (ADC_ON_12BIT | TSC2007_MEASURE_TEMP0));
0085         break;
0086     case 8:
0087         *val = tsc2007_xfer(tsc,
0088                     (ADC_ON_12BIT | TSC2007_MEASURE_TEMP1));
0089         break;
0090     }
0091
0092     /* Prepare for next touch reading - power down ADC, enable PENIRQ */
0093     tsc2007_xfer(tsc, PWRDOWN);
0094
0095     mutex_unlock(&tsc->mlock);
0096
0097     ret = IIO_VAL_INT;
0098
0099     return ret;
0100 }
0101
0102 static const struct iio_info tsc2007_iio_info = {
0103     .read_raw = tsc2007_read_raw,
0104 };
0105
0106 int tsc2007_iio_configure(struct tsc2007 *ts)
0107 {
0108     struct iio_dev *indio_dev;
0109     struct tsc2007_iio *iio;
0110     int error;
0111
0112     indio_dev = devm_iio_device_alloc(&ts->client->dev, sizeof(*iio));
0113     if (!indio_dev) {
0114         dev_err(&ts->client->dev, "iio_device_alloc failed\n");
0115         return -ENOMEM;
0116     }
0117
0118     iio = iio_priv(indio_dev);
0119     iio->ts = ts;
0120
0121     indio_dev->name = "tsc2007";
0122     indio_dev->info = &tsc2007_iio_info;
0123     indio_dev->modes = INDIO_DIRECT_MODE;
0124     indio_dev->channels = tsc2007_iio_channel;
0125     indio_dev->num_channels = ARRAY_SIZE(tsc2007_iio_channel);
0126
0127     error = devm_iio_device_register(&ts->client->dev, indio_dev);
0128     if (error) {
0129         dev_err(&ts->client->dev,
0130             "iio_device_register() failed: %d\n", error);
0131         return error;
0132     }
0133
0134     return 0;
0135 }