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}