1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * ADIS16080/100 Yaw Rate Gyroscope with SPI driver
4 *
5 * Copyright 2010 Analog Devices Inc.
6 */
7 #include <linux/delay.h>
8 #include <linux/mutex.h>
9 #include <linux/device.h>
10 #include <linux/kernel.h>
11 #include <linux/spi/spi.h>
12 #include <linux/slab.h>
13 #include <linux/sysfs.h>
14 #include <linux/module.h>
15
16 #include <linux/iio/iio.h>
17 #include <linux/iio/sysfs.h>
18
19 #define ADIS16080_DIN_GYRO (0 << 10) /* Gyroscope output */
20 #define ADIS16080_DIN_TEMP (1 << 10) /* Temperature output */
21 #define ADIS16080_DIN_AIN1 (2 << 10)
22 #define ADIS16080_DIN_AIN2 (3 << 10)
23
24 /*
25 * 1: Write contents on DIN to control register.
26 * 0: No changes to control register.
27 */
28
29 #define ADIS16080_DIN_WRITE (1 << 15)
30
31 struct adis16080_chip_info {
32 int scale_val;
33 int scale_val2;
34 };
35
36 /**
37 * struct adis16080_state - device instance specific data
38 * @us: actual spi_device to write data
39 * @info: chip specific parameters
40 * @buf: transmit or receive buffer
41 * @lock: lock to protect buffer during reads
42 **/
43 struct adis16080_state {
44 struct spi_device *us;
45 const struct adis16080_chip_info *info;
46 struct mutex lock;
47
48 __be16 buf __aligned(IIO_DMA_MINALIGN);
49 };
50
adis16080_read_sample(struct iio_dev * indio_dev,u16 addr,int * val)51 static int adis16080_read_sample(struct iio_dev *indio_dev,
52 u16 addr, int *val)
53 {
54 struct adis16080_state *st = iio_priv(indio_dev);
55 int ret;
56 struct spi_transfer t[] = {
57 {
58 .tx_buf = &st->buf,
59 .len = 2,
60 .cs_change = 1,
61 }, {
62 .rx_buf = &st->buf,
63 .len = 2,
64 },
65 };
66
67 st->buf = cpu_to_be16(addr | ADIS16080_DIN_WRITE);
68
69 ret = spi_sync_transfer(st->us, t, ARRAY_SIZE(t));
70 if (ret == 0)
71 *val = sign_extend32(be16_to_cpu(st->buf), 11);
72
73 return ret;
74 }
75
adis16080_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)76 static int adis16080_read_raw(struct iio_dev *indio_dev,
77 struct iio_chan_spec const *chan,
78 int *val,
79 int *val2,
80 long mask)
81 {
82 struct adis16080_state *st = iio_priv(indio_dev);
83 int ret;
84
85 switch (mask) {
86 case IIO_CHAN_INFO_RAW:
87 mutex_lock(&st->lock);
88 ret = adis16080_read_sample(indio_dev, chan->address, val);
89 mutex_unlock(&st->lock);
90 return ret ? ret : IIO_VAL_INT;
91 case IIO_CHAN_INFO_SCALE:
92 switch (chan->type) {
93 case IIO_ANGL_VEL:
94 *val = st->info->scale_val;
95 *val2 = st->info->scale_val2;
96 return IIO_VAL_FRACTIONAL;
97 case IIO_VOLTAGE:
98 /* VREF = 5V, 12 bits */
99 *val = 5000;
100 *val2 = 12;
101 return IIO_VAL_FRACTIONAL_LOG2;
102 case IIO_TEMP:
103 /* 85 C = 585, 25 C = 0 */
104 *val = 85000 - 25000;
105 *val2 = 585;
106 return IIO_VAL_FRACTIONAL;
107 default:
108 return -EINVAL;
109 }
110 case IIO_CHAN_INFO_OFFSET:
111 switch (chan->type) {
112 case IIO_VOLTAGE:
113 /* 2.5 V = 0 */
114 *val = 2048;
115 return IIO_VAL_INT;
116 case IIO_TEMP:
117 /* 85 C = 585, 25 C = 0 */
118 *val = DIV_ROUND_CLOSEST(25 * 585, 85 - 25);
119 return IIO_VAL_INT;
120 default:
121 return -EINVAL;
122 }
123 default:
124 break;
125 }
126
127 return -EINVAL;
128 }
129
130 static const struct iio_chan_spec adis16080_channels[] = {
131 {
132 .type = IIO_ANGL_VEL,
133 .modified = 1,
134 .channel2 = IIO_MOD_Z,
135 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
136 BIT(IIO_CHAN_INFO_SCALE),
137 .address = ADIS16080_DIN_GYRO,
138 }, {
139 .type = IIO_VOLTAGE,
140 .indexed = 1,
141 .channel = 0,
142 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
143 BIT(IIO_CHAN_INFO_SCALE) |
144 BIT(IIO_CHAN_INFO_OFFSET),
145 .address = ADIS16080_DIN_AIN1,
146 }, {
147 .type = IIO_VOLTAGE,
148 .indexed = 1,
149 .channel = 1,
150 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
151 BIT(IIO_CHAN_INFO_SCALE) |
152 BIT(IIO_CHAN_INFO_OFFSET),
153 .address = ADIS16080_DIN_AIN2,
154 }, {
155 .type = IIO_TEMP,
156 .indexed = 1,
157 .channel = 0,
158 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
159 BIT(IIO_CHAN_INFO_SCALE) |
160 BIT(IIO_CHAN_INFO_OFFSET),
161 .address = ADIS16080_DIN_TEMP,
162 }
163 };
164
165 static const struct iio_info adis16080_info = {
166 .read_raw = &adis16080_read_raw,
167 };
168
169 enum {
170 ID_ADIS16080,
171 ID_ADIS16100,
172 };
173
174 static const struct adis16080_chip_info adis16080_chip_info[] = {
175 [ID_ADIS16080] = {
176 /* 80 degree = 819, 819 rad = 46925 degree */
177 .scale_val = 80,
178 .scale_val2 = 46925,
179 },
180 [ID_ADIS16100] = {
181 /* 300 degree = 1230, 1230 rad = 70474 degree */
182 .scale_val = 300,
183 .scale_val2 = 70474,
184 },
185 };
186
adis16080_probe(struct spi_device * spi)187 static int adis16080_probe(struct spi_device *spi)
188 {
189 const struct spi_device_id *id = spi_get_device_id(spi);
190 struct adis16080_state *st;
191 struct iio_dev *indio_dev;
192
193 /* setup the industrialio driver allocated elements */
194 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
195 if (!indio_dev)
196 return -ENOMEM;
197 st = iio_priv(indio_dev);
198
199 mutex_init(&st->lock);
200
201 /* Allocate the comms buffers */
202 st->us = spi;
203 st->info = &adis16080_chip_info[id->driver_data];
204
205 indio_dev->name = spi->dev.driver->name;
206 indio_dev->channels = adis16080_channels;
207 indio_dev->num_channels = ARRAY_SIZE(adis16080_channels);
208 indio_dev->info = &adis16080_info;
209 indio_dev->modes = INDIO_DIRECT_MODE;
210
211 return devm_iio_device_register(&spi->dev, indio_dev);
212 }
213
214 static const struct spi_device_id adis16080_ids[] = {
215 { "adis16080", ID_ADIS16080 },
216 { "adis16100", ID_ADIS16100 },
217 {},
218 };
219 MODULE_DEVICE_TABLE(spi, adis16080_ids);
220
221 static struct spi_driver adis16080_driver = {
222 .driver = {
223 .name = "adis16080",
224 },
225 .probe = adis16080_probe,
226 .id_table = adis16080_ids,
227 };
228 module_spi_driver(adis16080_driver);
229
230 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
231 MODULE_DESCRIPTION("Analog Devices ADIS16080/100 Yaw Rate Gyroscope Driver");
232 MODULE_LICENSE("GPL v2");
233