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5
6#include <linux/err.h>
7#include <linux/delay.h>
8#include <linux/device.h>
9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/of.h>
12#include <linux/of_gpio.h>
13#include <linux/slab.h>
14#include <linux/sysfs.h>
15
16#include <linux/gpio/consumer.h>
17#include <linux/spi/spi.h>
18
19#include <linux/iio/iio.h>
20#include <linux/iio/buffer.h>
21#include <linux/iio/trigger_consumer.h>
22#include <linux/iio/triggered_buffer.h>
23#include <linux/iio/sysfs.h>
24
25
26#define ADS124S08_CMD_NOP 0x00
27#define ADS124S08_CMD_WAKEUP 0x02
28#define ADS124S08_CMD_PWRDWN 0x04
29#define ADS124S08_CMD_RESET 0x06
30#define ADS124S08_CMD_START 0x08
31#define ADS124S08_CMD_STOP 0x0a
32#define ADS124S08_CMD_SYOCAL 0x16
33#define ADS124S08_CMD_SYGCAL 0x17
34#define ADS124S08_CMD_SFOCAL 0x19
35#define ADS124S08_CMD_RDATA 0x12
36#define ADS124S08_CMD_RREG 0x20
37#define ADS124S08_CMD_WREG 0x40
38
39
40#define ADS124S08_ID_REG 0x00
41#define ADS124S08_STATUS 0x01
42#define ADS124S08_INPUT_MUX 0x02
43#define ADS124S08_PGA 0x03
44#define ADS124S08_DATA_RATE 0x04
45#define ADS124S08_REF 0x05
46#define ADS124S08_IDACMAG 0x06
47#define ADS124S08_IDACMUX 0x07
48#define ADS124S08_VBIAS 0x08
49#define ADS124S08_SYS 0x09
50#define ADS124S08_OFCAL0 0x0a
51#define ADS124S08_OFCAL1 0x0b
52#define ADS124S08_OFCAL2 0x0c
53#define ADS124S08_FSCAL0 0x0d
54#define ADS124S08_FSCAL1 0x0e
55#define ADS124S08_FSCAL2 0x0f
56#define ADS124S08_GPIODAT 0x10
57#define ADS124S08_GPIOCON 0x11
58
59
60#define ADS124S08_AIN0 0x00
61#define ADS124S08_AIN1 0x01
62#define ADS124S08_AIN2 0x02
63#define ADS124S08_AIN3 0x03
64#define ADS124S08_AIN4 0x04
65#define ADS124S08_AIN5 0x05
66#define ADS124S08_AINCOM 0x0c
67
68#define ADS124S08_AIN6 0x06
69#define ADS124S08_AIN7 0x07
70#define ADS124S08_AIN8 0x08
71#define ADS124S08_AIN9 0x09
72#define ADS124S08_AIN10 0x0a
73#define ADS124S08_AIN11 0x0b
74#define ADS124S08_MAX_CHANNELS 12
75
76#define ADS124S08_POS_MUX_SHIFT 0x04
77#define ADS124S08_INT_REF 0x09
78
79#define ADS124S08_START_REG_MASK 0x1f
80#define ADS124S08_NUM_BYTES_MASK 0x1f
81
82#define ADS124S08_START_CONV 0x01
83#define ADS124S08_STOP_CONV 0x00
84
85enum ads124s_id {
86 ADS124S08_ID,
87 ADS124S06_ID,
88};
89
90struct ads124s_chip_info {
91 const struct iio_chan_spec *channels;
92 unsigned int num_channels;
93};
94
95struct ads124s_private {
96 const struct ads124s_chip_info *chip_info;
97 struct gpio_desc *reset_gpio;
98 struct spi_device *spi;
99 struct mutex lock;
100 u8 data[5] ____cacheline_aligned;
101};
102
103#define ADS124S08_CHAN(index) \
104{ \
105 .type = IIO_VOLTAGE, \
106 .indexed = 1, \
107 .channel = index, \
108 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
109 .scan_index = index, \
110 .scan_type = { \
111 .sign = 'u', \
112 .realbits = 32, \
113 .storagebits = 32, \
114 }, \
115}
116
117static const struct iio_chan_spec ads124s06_channels[] = {
118 ADS124S08_CHAN(0),
119 ADS124S08_CHAN(1),
120 ADS124S08_CHAN(2),
121 ADS124S08_CHAN(3),
122 ADS124S08_CHAN(4),
123 ADS124S08_CHAN(5),
124};
125
126static const struct iio_chan_spec ads124s08_channels[] = {
127 ADS124S08_CHAN(0),
128 ADS124S08_CHAN(1),
129 ADS124S08_CHAN(2),
130 ADS124S08_CHAN(3),
131 ADS124S08_CHAN(4),
132 ADS124S08_CHAN(5),
133 ADS124S08_CHAN(6),
134 ADS124S08_CHAN(7),
135 ADS124S08_CHAN(8),
136 ADS124S08_CHAN(9),
137 ADS124S08_CHAN(10),
138 ADS124S08_CHAN(11),
139};
140
141static const struct ads124s_chip_info ads124s_chip_info_tbl[] = {
142 [ADS124S08_ID] = {
143 .channels = ads124s08_channels,
144 .num_channels = ARRAY_SIZE(ads124s08_channels),
145 },
146 [ADS124S06_ID] = {
147 .channels = ads124s06_channels,
148 .num_channels = ARRAY_SIZE(ads124s06_channels),
149 },
150};
151
152static int ads124s_write_cmd(struct iio_dev *indio_dev, u8 command)
153{
154 struct ads124s_private *priv = iio_priv(indio_dev);
155
156 priv->data[0] = command;
157
158 return spi_write(priv->spi, &priv->data[0], 1);
159}
160
161static int ads124s_write_reg(struct iio_dev *indio_dev, u8 reg, u8 data)
162{
163 struct ads124s_private *priv = iio_priv(indio_dev);
164
165 priv->data[0] = ADS124S08_CMD_WREG | reg;
166 priv->data[1] = 0x0;
167 priv->data[2] = data;
168
169 return spi_write(priv->spi, &priv->data[0], 3);
170}
171
172static int ads124s_reset(struct iio_dev *indio_dev)
173{
174 struct ads124s_private *priv = iio_priv(indio_dev);
175
176 if (priv->reset_gpio) {
177 gpiod_set_value(priv->reset_gpio, 0);
178 udelay(200);
179 gpiod_set_value(priv->reset_gpio, 1);
180 } else {
181 return ads124s_write_cmd(indio_dev, ADS124S08_CMD_RESET);
182 }
183
184 return 0;
185};
186
187static int ads124s_read(struct iio_dev *indio_dev, unsigned int chan)
188{
189 struct ads124s_private *priv = iio_priv(indio_dev);
190 int ret;
191 u32 tmp;
192 struct spi_transfer t[] = {
193 {
194 .tx_buf = &priv->data[0],
195 .len = 4,
196 .cs_change = 1,
197 }, {
198 .tx_buf = &priv->data[1],
199 .rx_buf = &priv->data[1],
200 .len = 4,
201 },
202 };
203
204 priv->data[0] = ADS124S08_CMD_RDATA;
205 memset(&priv->data[1], ADS124S08_CMD_NOP, sizeof(priv->data) - 1);
206
207 ret = spi_sync_transfer(priv->spi, t, ARRAY_SIZE(t));
208 if (ret < 0)
209 return ret;
210
211 tmp = priv->data[2] << 16 | priv->data[3] << 8 | priv->data[4];
212
213 return tmp;
214}
215
216static int ads124s_read_raw(struct iio_dev *indio_dev,
217 struct iio_chan_spec const *chan,
218 int *val, int *val2, long m)
219{
220 struct ads124s_private *priv = iio_priv(indio_dev);
221 int ret;
222
223 mutex_lock(&priv->lock);
224 switch (m) {
225 case IIO_CHAN_INFO_RAW:
226 ret = ads124s_write_reg(indio_dev, ADS124S08_INPUT_MUX,
227 chan->channel);
228 if (ret) {
229 dev_err(&priv->spi->dev, "Set ADC CH failed\n");
230 goto out;
231 }
232
233 ret = ads124s_write_cmd(indio_dev, ADS124S08_START_CONV);
234 if (ret) {
235 dev_err(&priv->spi->dev, "Start conversions failed\n");
236 goto out;
237 }
238
239 ret = ads124s_read(indio_dev, chan->channel);
240 if (ret < 0) {
241 dev_err(&priv->spi->dev, "Read ADC failed\n");
242 goto out;
243 }
244
245 *val = ret;
246
247 ret = ads124s_write_cmd(indio_dev, ADS124S08_STOP_CONV);
248 if (ret) {
249 dev_err(&priv->spi->dev, "Stop conversions failed\n");
250 goto out;
251 }
252
253 ret = IIO_VAL_INT;
254 break;
255 default:
256 ret = -EINVAL;
257 break;
258 }
259out:
260 mutex_unlock(&priv->lock);
261 return ret;
262}
263
264static const struct iio_info ads124s_info = {
265 .read_raw = &ads124s_read_raw,
266};
267
268static irqreturn_t ads124s_trigger_handler(int irq, void *p)
269{
270 struct iio_poll_func *pf = p;
271 struct iio_dev *indio_dev = pf->indio_dev;
272 struct ads124s_private *priv = iio_priv(indio_dev);
273 u32 buffer[ADS124S08_MAX_CHANNELS + sizeof(s64)/sizeof(u16)];
274 int scan_index, j = 0;
275 int ret;
276
277 for_each_set_bit(scan_index, indio_dev->active_scan_mask,
278 indio_dev->masklength) {
279 ret = ads124s_write_reg(indio_dev, ADS124S08_INPUT_MUX,
280 scan_index);
281 if (ret)
282 dev_err(&priv->spi->dev, "Set ADC CH failed\n");
283
284 ret = ads124s_write_cmd(indio_dev, ADS124S08_START_CONV);
285 if (ret)
286 dev_err(&priv->spi->dev, "Start ADC conversions failed\n");
287
288 buffer[j] = ads124s_read(indio_dev, scan_index);
289 ret = ads124s_write_cmd(indio_dev, ADS124S08_STOP_CONV);
290 if (ret)
291 dev_err(&priv->spi->dev, "Stop ADC conversions failed\n");
292
293 j++;
294 }
295
296 iio_push_to_buffers_with_timestamp(indio_dev, buffer,
297 pf->timestamp);
298
299 iio_trigger_notify_done(indio_dev->trig);
300
301 return IRQ_HANDLED;
302}
303
304static int ads124s_probe(struct spi_device *spi)
305{
306 struct ads124s_private *ads124s_priv;
307 struct iio_dev *indio_dev;
308 const struct spi_device_id *spi_id = spi_get_device_id(spi);
309 int ret;
310
311 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*ads124s_priv));
312 if (indio_dev == NULL)
313 return -ENOMEM;
314
315 ads124s_priv = iio_priv(indio_dev);
316
317 ads124s_priv->reset_gpio = devm_gpiod_get_optional(&spi->dev,
318 "reset", GPIOD_OUT_LOW);
319 if (IS_ERR(ads124s_priv->reset_gpio))
320 dev_info(&spi->dev, "Reset GPIO not defined\n");
321
322 ads124s_priv->chip_info = &ads124s_chip_info_tbl[spi_id->driver_data];
323
324 spi_set_drvdata(spi, indio_dev);
325
326 ads124s_priv->spi = spi;
327
328 indio_dev->name = spi_id->name;
329 indio_dev->dev.parent = &spi->dev;
330 indio_dev->dev.of_node = spi->dev.of_node;
331 indio_dev->modes = INDIO_DIRECT_MODE;
332 indio_dev->channels = ads124s_priv->chip_info->channels;
333 indio_dev->num_channels = ads124s_priv->chip_info->num_channels;
334 indio_dev->info = &ads124s_info;
335
336 mutex_init(&ads124s_priv->lock);
337
338 ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, NULL,
339 ads124s_trigger_handler, NULL);
340 if (ret) {
341 dev_err(&spi->dev, "iio triggered buffer setup failed\n");
342 return ret;
343 }
344
345 ads124s_reset(indio_dev);
346
347 return devm_iio_device_register(&spi->dev, indio_dev);
348}
349
350static const struct spi_device_id ads124s_id[] = {
351 { "ads124s06", ADS124S06_ID },
352 { "ads124s08", ADS124S08_ID },
353 { }
354};
355MODULE_DEVICE_TABLE(spi, ads124s_id);
356
357static const struct of_device_id ads124s_of_table[] = {
358 { .compatible = "ti,ads124s06" },
359 { .compatible = "ti,ads124s08" },
360 { },
361};
362MODULE_DEVICE_TABLE(of, ads124s_of_table);
363
364static struct spi_driver ads124s_driver = {
365 .driver = {
366 .name = "ads124s08",
367 .of_match_table = ads124s_of_table,
368 },
369 .probe = ads124s_probe,
370 .id_table = ads124s_id,
371};
372module_spi_driver(ads124s_driver);
373
374MODULE_AUTHOR("Dan Murphy <dmuprhy@ti.com>");
375MODULE_DESCRIPTION("TI TI_ADS12S0X ADC");
376MODULE_LICENSE("GPL v2");
377
