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 }
136