xref: /linux/drivers/input/touchscreen/tsc2007_iio.c (revision ffd01c3bcc1af4d8c3e7949152af0d9fe3d1fda5)
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 
45 	if (adc_chan >= ARRAY_SIZE(tsc2007_iio_channel))
46 		return -EINVAL;
47 
48 	if (mask != IIO_CHAN_INFO_RAW)
49 		return -EINVAL;
50 
51 	guard(mutex)(&tsc->mlock);
52 
53 	switch (chan->channel) {
54 	case 0:
55 		*val = tsc2007_xfer(tsc, READ_X);
56 		break;
57 	case 1:
58 		*val = tsc2007_xfer(tsc, READ_Y);
59 		break;
60 	case 2:
61 		*val = tsc2007_xfer(tsc, READ_Z1);
62 		break;
63 	case 3:
64 		*val = tsc2007_xfer(tsc, READ_Z2);
65 		break;
66 	case 4:
67 		*val = tsc2007_xfer(tsc, (ADC_ON_12BIT | TSC2007_MEASURE_AUX));
68 		break;
69 	case 5: {
70 		struct ts_event tc;
71 
72 		tc.x = tsc2007_xfer(tsc, READ_X);
73 		tc.z1 = tsc2007_xfer(tsc, READ_Z1);
74 		tc.z2 = tsc2007_xfer(tsc, READ_Z2);
75 		*val = tsc2007_calculate_resistance(tsc, &tc);
76 		break;
77 	}
78 	case 6:
79 		*val = tsc2007_is_pen_down(tsc);
80 		break;
81 	case 7:
82 		*val = tsc2007_xfer(tsc,
83 				    (ADC_ON_12BIT | TSC2007_MEASURE_TEMP0));
84 		break;
85 	case 8:
86 		*val = tsc2007_xfer(tsc,
87 				    (ADC_ON_12BIT | TSC2007_MEASURE_TEMP1));
88 		break;
89 	}
90 
91 	/* Prepare for next touch reading - power down ADC, enable PENIRQ */
92 	tsc2007_xfer(tsc, PWRDOWN);
93 
94 	return IIO_VAL_INT;
95 }
96 
97 static const struct iio_info tsc2007_iio_info = {
98 	.read_raw = tsc2007_read_raw,
99 };
100 
101 int tsc2007_iio_configure(struct tsc2007 *ts)
102 {
103 	struct iio_dev *indio_dev;
104 	struct tsc2007_iio *iio;
105 	int error;
106 
107 	indio_dev = devm_iio_device_alloc(&ts->client->dev, sizeof(*iio));
108 	if (!indio_dev) {
109 		dev_err(&ts->client->dev, "iio_device_alloc failed\n");
110 		return -ENOMEM;
111 	}
112 
113 	iio = iio_priv(indio_dev);
114 	iio->ts = ts;
115 
116 	indio_dev->name = "tsc2007";
117 	indio_dev->info = &tsc2007_iio_info;
118 	indio_dev->modes = INDIO_DIRECT_MODE;
119 	indio_dev->channels = tsc2007_iio_channel;
120 	indio_dev->num_channels = ARRAY_SIZE(tsc2007_iio_channel);
121 
122 	error = devm_iio_device_register(&ts->client->dev, indio_dev);
123 	if (error) {
124 		dev_err(&ts->client->dev,
125 			"iio_device_register() failed: %d\n", error);
126 		return error;
127 	}
128 
129 	return 0;
130 }
131