1 /*
2 * AD7785/AD7792/AD7793/AD7794/AD7795 SPI ADC driver
3 *
4 * Copyright 2011-2012 Analog Devices Inc.
5 *
6 * Licensed under the GPL-2.
7 */
8
9 #include <linux/interrupt.h>
10 #include <linux/device.h>
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
13 #include <linux/sysfs.h>
14 #include <linux/spi/spi.h>
15 #include <linux/regulator/consumer.h>
16 #include <linux/err.h>
17 #include <linux/sched.h>
18 #include <linux/delay.h>
19 #include <linux/module.h>
20
21 #include <linux/iio/iio.h>
22 #include <linux/iio/sysfs.h>
23 #include <linux/iio/buffer.h>
24 #include <linux/iio/trigger.h>
25 #include <linux/iio/trigger_consumer.h>
26 #include <linux/iio/triggered_buffer.h>
27 #include <linux/iio/adc/ad_sigma_delta.h>
28 #include <linux/platform_data/ad7793.h>
29
30 /* Registers */
31 #define AD7793_REG_COMM 0 /* Communications Register (WO, 8-bit) */
32 #define AD7793_REG_STAT 0 /* Status Register (RO, 8-bit) */
33 #define AD7793_REG_MODE 1 /* Mode Register (RW, 16-bit */
34 #define AD7793_REG_CONF 2 /* Configuration Register (RW, 16-bit) */
35 #define AD7793_REG_DATA 3 /* Data Register (RO, 16-/24-bit) */
36 #define AD7793_REG_ID 4 /* ID Register (RO, 8-bit) */
37 #define AD7793_REG_IO 5 /* IO Register (RO, 8-bit) */
38 #define AD7793_REG_OFFSET 6 /* Offset Register (RW, 16-bit
39 * (AD7792)/24-bit (AD7793)) */
40 #define AD7793_REG_FULLSALE 7 /* Full-Scale Register
41 * (RW, 16-bit (AD7792)/24-bit (AD7793)) */
42
43 /* Communications Register Bit Designations (AD7793_REG_COMM) */
44 #define AD7793_COMM_WEN (1 << 7) /* Write Enable */
45 #define AD7793_COMM_WRITE (0 << 6) /* Write Operation */
46 #define AD7793_COMM_READ (1 << 6) /* Read Operation */
47 #define AD7793_COMM_ADDR(x) (((x) & 0x7) << 3) /* Register Address */
48 #define AD7793_COMM_CREAD (1 << 2) /* Continuous Read of Data Register */
49
50 /* Status Register Bit Designations (AD7793_REG_STAT) */
51 #define AD7793_STAT_RDY (1 << 7) /* Ready */
52 #define AD7793_STAT_ERR (1 << 6) /* Error (Overrange, Underrange) */
53 #define AD7793_STAT_CH3 (1 << 2) /* Channel 3 */
54 #define AD7793_STAT_CH2 (1 << 1) /* Channel 2 */
55 #define AD7793_STAT_CH1 (1 << 0) /* Channel 1 */
56
57 /* Mode Register Bit Designations (AD7793_REG_MODE) */
58 #define AD7793_MODE_SEL(x) (((x) & 0x7) << 13) /* Operation Mode Select */
59 #define AD7793_MODE_SEL_MASK (0x7 << 13) /* Operation Mode Select mask */
60 #define AD7793_MODE_CLKSRC(x) (((x) & 0x3) << 6) /* ADC Clock Source Select */
61 #define AD7793_MODE_RATE(x) ((x) & 0xF) /* Filter Update Rate Select */
62
63 #define AD7793_MODE_CONT 0 /* Continuous Conversion Mode */
64 #define AD7793_MODE_SINGLE 1 /* Single Conversion Mode */
65 #define AD7793_MODE_IDLE 2 /* Idle Mode */
66 #define AD7793_MODE_PWRDN 3 /* Power-Down Mode */
67 #define AD7793_MODE_CAL_INT_ZERO 4 /* Internal Zero-Scale Calibration */
68 #define AD7793_MODE_CAL_INT_FULL 5 /* Internal Full-Scale Calibration */
69 #define AD7793_MODE_CAL_SYS_ZERO 6 /* System Zero-Scale Calibration */
70 #define AD7793_MODE_CAL_SYS_FULL 7 /* System Full-Scale Calibration */
71
72 #define AD7793_CLK_INT 0 /* Internal 64 kHz Clock not
73 * available at the CLK pin */
74 #define AD7793_CLK_INT_CO 1 /* Internal 64 kHz Clock available
75 * at the CLK pin */
76 #define AD7793_CLK_EXT 2 /* External 64 kHz Clock */
77 #define AD7793_CLK_EXT_DIV2 3 /* External Clock divided by 2 */
78
79 /* Configuration Register Bit Designations (AD7793_REG_CONF) */
80 #define AD7793_CONF_VBIAS(x) (((x) & 0x3) << 14) /* Bias Voltage
81 * Generator Enable */
82 #define AD7793_CONF_BO_EN (1 << 13) /* Burnout Current Enable */
83 #define AD7793_CONF_UNIPOLAR (1 << 12) /* Unipolar/Bipolar Enable */
84 #define AD7793_CONF_BOOST (1 << 11) /* Boost Enable */
85 #define AD7793_CONF_GAIN(x) (((x) & 0x7) << 8) /* Gain Select */
86 #define AD7793_CONF_REFSEL(x) ((x) << 6) /* INT/EXT Reference Select */
87 #define AD7793_CONF_BUF (1 << 4) /* Buffered Mode Enable */
88 #define AD7793_CONF_CHAN(x) ((x) & 0xf) /* Channel select */
89 #define AD7793_CONF_CHAN_MASK 0xf /* Channel select mask */
90
91 #define AD7793_CH_AIN1P_AIN1M 0 /* AIN1(+) - AIN1(-) */
92 #define AD7793_CH_AIN2P_AIN2M 1 /* AIN2(+) - AIN2(-) */
93 #define AD7793_CH_AIN3P_AIN3M 2 /* AIN3(+) - AIN3(-) */
94 #define AD7793_CH_AIN1M_AIN1M 3 /* AIN1(-) - AIN1(-) */
95 #define AD7793_CH_TEMP 6 /* Temp Sensor */
96 #define AD7793_CH_AVDD_MONITOR 7 /* AVDD Monitor */
97
98 #define AD7795_CH_AIN4P_AIN4M 4 /* AIN4(+) - AIN4(-) */
99 #define AD7795_CH_AIN5P_AIN5M 5 /* AIN5(+) - AIN5(-) */
100 #define AD7795_CH_AIN6P_AIN6M 6 /* AIN6(+) - AIN6(-) */
101 #define AD7795_CH_AIN1M_AIN1M 8 /* AIN1(-) - AIN1(-) */
102
103 /* ID Register Bit Designations (AD7793_REG_ID) */
104 #define AD7785_ID 0x3
105 #define AD7792_ID 0xA
106 #define AD7793_ID 0xB
107 #define AD7794_ID 0xF
108 #define AD7795_ID 0xF
109 #define AD7796_ID 0xA
110 #define AD7797_ID 0xB
111 #define AD7798_ID 0x8
112 #define AD7799_ID 0x9
113 #define AD7793_ID_MASK 0xF
114
115 /* IO (Excitation Current Sources) Register Bit Designations (AD7793_REG_IO) */
116 #define AD7793_IO_IEXC1_IOUT1_IEXC2_IOUT2 0 /* IEXC1 connect to IOUT1,
117 * IEXC2 connect to IOUT2 */
118 #define AD7793_IO_IEXC1_IOUT2_IEXC2_IOUT1 1 /* IEXC1 connect to IOUT2,
119 * IEXC2 connect to IOUT1 */
120 #define AD7793_IO_IEXC1_IEXC2_IOUT1 2 /* Both current sources
121 * IEXC1,2 connect to IOUT1 */
122 #define AD7793_IO_IEXC1_IEXC2_IOUT2 3 /* Both current sources
123 * IEXC1,2 connect to IOUT2 */
124
125 #define AD7793_IO_IXCEN_10uA (1 << 0) /* Excitation Current 10uA */
126 #define AD7793_IO_IXCEN_210uA (2 << 0) /* Excitation Current 210uA */
127 #define AD7793_IO_IXCEN_1mA (3 << 0) /* Excitation Current 1mA */
128
129 /* NOTE:
130 * The AD7792/AD7793 features a dual use data out ready DOUT/RDY output.
131 * In order to avoid contentions on the SPI bus, it's therefore necessary
132 * to use spi bus locking.
133 *
134 * The DOUT/RDY output must also be wired to an interrupt capable GPIO.
135 */
136
137 #define AD7793_FLAG_HAS_CLKSEL BIT(0)
138 #define AD7793_FLAG_HAS_REFSEL BIT(1)
139 #define AD7793_FLAG_HAS_VBIAS BIT(2)
140 #define AD7793_HAS_EXITATION_CURRENT BIT(3)
141 #define AD7793_FLAG_HAS_GAIN BIT(4)
142 #define AD7793_FLAG_HAS_BUFFER BIT(5)
143
144 struct ad7793_chip_info {
145 unsigned int id;
146 const struct iio_chan_spec *channels;
147 unsigned int num_channels;
148 unsigned int flags;
149
150 const struct iio_info *iio_info;
151 const u16 *sample_freq_avail;
152 };
153
154 struct ad7793_state {
155 const struct ad7793_chip_info *chip_info;
156 struct regulator *reg;
157 u16 int_vref_mv;
158 u16 mode;
159 u16 conf;
160 u32 scale_avail[8][2];
161
162 struct ad_sigma_delta sd;
163
164 };
165
166 enum ad7793_supported_device_ids {
167 ID_AD7785,
168 ID_AD7792,
169 ID_AD7793,
170 ID_AD7794,
171 ID_AD7795,
172 ID_AD7796,
173 ID_AD7797,
174 ID_AD7798,
175 ID_AD7799,
176 };
177
ad_sigma_delta_to_ad7793(struct ad_sigma_delta * sd)178 static struct ad7793_state *ad_sigma_delta_to_ad7793(struct ad_sigma_delta *sd)
179 {
180 return container_of(sd, struct ad7793_state, sd);
181 }
182
ad7793_set_channel(struct ad_sigma_delta * sd,unsigned int channel)183 static int ad7793_set_channel(struct ad_sigma_delta *sd, unsigned int channel)
184 {
185 struct ad7793_state *st = ad_sigma_delta_to_ad7793(sd);
186
187 st->conf &= ~AD7793_CONF_CHAN_MASK;
188 st->conf |= AD7793_CONF_CHAN(channel);
189
190 return ad_sd_write_reg(&st->sd, AD7793_REG_CONF, 2, st->conf);
191 }
192
ad7793_set_mode(struct ad_sigma_delta * sd,enum ad_sigma_delta_mode mode)193 static int ad7793_set_mode(struct ad_sigma_delta *sd,
194 enum ad_sigma_delta_mode mode)
195 {
196 struct ad7793_state *st = ad_sigma_delta_to_ad7793(sd);
197
198 st->mode &= ~AD7793_MODE_SEL_MASK;
199 st->mode |= AD7793_MODE_SEL(mode);
200
201 return ad_sd_write_reg(&st->sd, AD7793_REG_MODE, 2, st->mode);
202 }
203
204 static const struct ad_sigma_delta_info ad7793_sigma_delta_info = {
205 .set_channel = ad7793_set_channel,
206 .set_mode = ad7793_set_mode,
207 .has_registers = true,
208 .addr_shift = 3,
209 .read_mask = BIT(6),
210 };
211
212 static const struct ad_sd_calib_data ad7793_calib_arr[6] = {
213 {AD7793_MODE_CAL_INT_ZERO, AD7793_CH_AIN1P_AIN1M},
214 {AD7793_MODE_CAL_INT_FULL, AD7793_CH_AIN1P_AIN1M},
215 {AD7793_MODE_CAL_INT_ZERO, AD7793_CH_AIN2P_AIN2M},
216 {AD7793_MODE_CAL_INT_FULL, AD7793_CH_AIN2P_AIN2M},
217 {AD7793_MODE_CAL_INT_ZERO, AD7793_CH_AIN3P_AIN3M},
218 {AD7793_MODE_CAL_INT_FULL, AD7793_CH_AIN3P_AIN3M}
219 };
220
ad7793_calibrate_all(struct ad7793_state * st)221 static int ad7793_calibrate_all(struct ad7793_state *st)
222 {
223 return ad_sd_calibrate_all(&st->sd, ad7793_calib_arr,
224 ARRAY_SIZE(ad7793_calib_arr));
225 }
226
ad7793_check_platform_data(struct ad7793_state * st,const struct ad7793_platform_data * pdata)227 static int ad7793_check_platform_data(struct ad7793_state *st,
228 const struct ad7793_platform_data *pdata)
229 {
230 if ((pdata->current_source_direction == AD7793_IEXEC1_IEXEC2_IOUT1 ||
231 pdata->current_source_direction == AD7793_IEXEC1_IEXEC2_IOUT2) &&
232 ((pdata->exitation_current != AD7793_IX_10uA) &&
233 (pdata->exitation_current != AD7793_IX_210uA)))
234 return -EINVAL;
235
236 if (!(st->chip_info->flags & AD7793_FLAG_HAS_CLKSEL) &&
237 pdata->clock_src != AD7793_CLK_SRC_INT)
238 return -EINVAL;
239
240 if (!(st->chip_info->flags & AD7793_FLAG_HAS_REFSEL) &&
241 pdata->refsel != AD7793_REFSEL_REFIN1)
242 return -EINVAL;
243
244 if (!(st->chip_info->flags & AD7793_FLAG_HAS_VBIAS) &&
245 pdata->bias_voltage != AD7793_BIAS_VOLTAGE_DISABLED)
246 return -EINVAL;
247
248 if (!(st->chip_info->flags & AD7793_HAS_EXITATION_CURRENT) &&
249 pdata->exitation_current != AD7793_IX_DISABLED)
250 return -EINVAL;
251
252 return 0;
253 }
254
ad7793_setup(struct iio_dev * indio_dev,const struct ad7793_platform_data * pdata,unsigned int vref_mv)255 static int ad7793_setup(struct iio_dev *indio_dev,
256 const struct ad7793_platform_data *pdata,
257 unsigned int vref_mv)
258 {
259 struct ad7793_state *st = iio_priv(indio_dev);
260 int i, ret;
261 unsigned long long scale_uv;
262 u32 id;
263
264 ret = ad7793_check_platform_data(st, pdata);
265 if (ret)
266 return ret;
267
268 /* reset the serial interface */
269 ret = ad_sd_reset(&st->sd, 32);
270 if (ret < 0)
271 goto out;
272 usleep_range(500, 2000); /* Wait for at least 500us */
273
274 /* write/read test for device presence */
275 ret = ad_sd_read_reg(&st->sd, AD7793_REG_ID, 1, &id);
276 if (ret)
277 goto out;
278
279 id &= AD7793_ID_MASK;
280
281 if (id != st->chip_info->id) {
282 ret = -ENODEV;
283 dev_err(&st->sd.spi->dev, "device ID query failed\n");
284 goto out;
285 }
286
287 st->mode = AD7793_MODE_RATE(1);
288 st->conf = 0;
289
290 if (st->chip_info->flags & AD7793_FLAG_HAS_CLKSEL)
291 st->mode |= AD7793_MODE_CLKSRC(pdata->clock_src);
292 if (st->chip_info->flags & AD7793_FLAG_HAS_REFSEL)
293 st->conf |= AD7793_CONF_REFSEL(pdata->refsel);
294 if (st->chip_info->flags & AD7793_FLAG_HAS_VBIAS)
295 st->conf |= AD7793_CONF_VBIAS(pdata->bias_voltage);
296 if (pdata->buffered || !(st->chip_info->flags & AD7793_FLAG_HAS_BUFFER))
297 st->conf |= AD7793_CONF_BUF;
298 if (pdata->boost_enable &&
299 (st->chip_info->flags & AD7793_FLAG_HAS_VBIAS))
300 st->conf |= AD7793_CONF_BOOST;
301 if (pdata->burnout_current)
302 st->conf |= AD7793_CONF_BO_EN;
303 if (pdata->unipolar)
304 st->conf |= AD7793_CONF_UNIPOLAR;
305
306 if (!(st->chip_info->flags & AD7793_FLAG_HAS_GAIN))
307 st->conf |= AD7793_CONF_GAIN(7);
308
309 ret = ad7793_set_mode(&st->sd, AD_SD_MODE_IDLE);
310 if (ret)
311 goto out;
312
313 ret = ad7793_set_channel(&st->sd, 0);
314 if (ret)
315 goto out;
316
317 if (st->chip_info->flags & AD7793_HAS_EXITATION_CURRENT) {
318 ret = ad_sd_write_reg(&st->sd, AD7793_REG_IO, 1,
319 pdata->exitation_current |
320 (pdata->current_source_direction << 2));
321 if (ret)
322 goto out;
323 }
324
325 ret = ad7793_calibrate_all(st);
326 if (ret)
327 goto out;
328
329 /* Populate available ADC input ranges */
330 for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) {
331 scale_uv = ((u64)vref_mv * 100000000)
332 >> (st->chip_info->channels[0].scan_type.realbits -
333 (!!(st->conf & AD7793_CONF_UNIPOLAR) ? 0 : 1));
334 scale_uv >>= i;
335
336 st->scale_avail[i][1] = do_div(scale_uv, 100000000) * 10;
337 st->scale_avail[i][0] = scale_uv;
338 }
339
340 return 0;
341 out:
342 dev_err(&st->sd.spi->dev, "setup failed\n");
343 return ret;
344 }
345
346 static const u16 ad7793_sample_freq_avail[16] = {0, 470, 242, 123, 62, 50, 39,
347 33, 19, 17, 16, 12, 10, 8, 6, 4};
348
349 static const u16 ad7797_sample_freq_avail[16] = {0, 0, 0, 123, 62, 50, 0,
350 33, 0, 17, 16, 12, 10, 8, 6, 4};
351
ad7793_read_frequency(struct device * dev,struct device_attribute * attr,char * buf)352 static ssize_t ad7793_read_frequency(struct device *dev,
353 struct device_attribute *attr,
354 char *buf)
355 {
356 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
357 struct ad7793_state *st = iio_priv(indio_dev);
358
359 return sprintf(buf, "%d\n",
360 st->chip_info->sample_freq_avail[AD7793_MODE_RATE(st->mode)]);
361 }
362
ad7793_write_frequency(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)363 static ssize_t ad7793_write_frequency(struct device *dev,
364 struct device_attribute *attr,
365 const char *buf,
366 size_t len)
367 {
368 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
369 struct ad7793_state *st = iio_priv(indio_dev);
370 long lval;
371 int i, ret;
372
373 mutex_lock(&indio_dev->mlock);
374 if (iio_buffer_enabled(indio_dev)) {
375 mutex_unlock(&indio_dev->mlock);
376 return -EBUSY;
377 }
378 mutex_unlock(&indio_dev->mlock);
379
380 ret = kstrtol(buf, 10, &lval);
381 if (ret)
382 return ret;
383
384 if (lval == 0)
385 return -EINVAL;
386
387 ret = -EINVAL;
388
389 for (i = 0; i < 16; i++)
390 if (lval == st->chip_info->sample_freq_avail[i]) {
391 mutex_lock(&indio_dev->mlock);
392 st->mode &= ~AD7793_MODE_RATE(-1);
393 st->mode |= AD7793_MODE_RATE(i);
394 ad_sd_write_reg(&st->sd, AD7793_REG_MODE,
395 sizeof(st->mode), st->mode);
396 mutex_unlock(&indio_dev->mlock);
397 ret = 0;
398 }
399
400 return ret ? ret : len;
401 }
402
403 static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
404 ad7793_read_frequency,
405 ad7793_write_frequency);
406
407 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
408 "470 242 123 62 50 39 33 19 17 16 12 10 8 6 4");
409
410 static IIO_CONST_ATTR_NAMED(sampling_frequency_available_ad7797,
411 sampling_frequency_available, "123 62 50 33 17 16 12 10 8 6 4");
412
ad7793_show_scale_available(struct device * dev,struct device_attribute * attr,char * buf)413 static ssize_t ad7793_show_scale_available(struct device *dev,
414 struct device_attribute *attr, char *buf)
415 {
416 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
417 struct ad7793_state *st = iio_priv(indio_dev);
418 int i, len = 0;
419
420 for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++)
421 len += sprintf(buf + len, "%d.%09u ", st->scale_avail[i][0],
422 st->scale_avail[i][1]);
423
424 len += sprintf(buf + len, "\n");
425
426 return len;
427 }
428
429 static IIO_DEVICE_ATTR_NAMED(in_m_in_scale_available,
430 in_voltage-voltage_scale_available, S_IRUGO,
431 ad7793_show_scale_available, NULL, 0);
432
433 static struct attribute *ad7793_attributes[] = {
434 &iio_dev_attr_sampling_frequency.dev_attr.attr,
435 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
436 &iio_dev_attr_in_m_in_scale_available.dev_attr.attr,
437 NULL
438 };
439
440 static const struct attribute_group ad7793_attribute_group = {
441 .attrs = ad7793_attributes,
442 };
443
444 static struct attribute *ad7797_attributes[] = {
445 &iio_dev_attr_sampling_frequency.dev_attr.attr,
446 &iio_const_attr_sampling_frequency_available_ad7797.dev_attr.attr,
447 NULL
448 };
449
450 static const struct attribute_group ad7797_attribute_group = {
451 .attrs = ad7797_attributes,
452 };
453
ad7793_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long m)454 static int ad7793_read_raw(struct iio_dev *indio_dev,
455 struct iio_chan_spec const *chan,
456 int *val,
457 int *val2,
458 long m)
459 {
460 struct ad7793_state *st = iio_priv(indio_dev);
461 int ret;
462 unsigned long long scale_uv;
463 bool unipolar = !!(st->conf & AD7793_CONF_UNIPOLAR);
464
465 switch (m) {
466 case IIO_CHAN_INFO_RAW:
467 ret = ad_sigma_delta_single_conversion(indio_dev, chan, val);
468 if (ret < 0)
469 return ret;
470
471 return IIO_VAL_INT;
472
473 case IIO_CHAN_INFO_SCALE:
474 switch (chan->type) {
475 case IIO_VOLTAGE:
476 if (chan->differential) {
477 *val = st->
478 scale_avail[(st->conf >> 8) & 0x7][0];
479 *val2 = st->
480 scale_avail[(st->conf >> 8) & 0x7][1];
481 return IIO_VAL_INT_PLUS_NANO;
482 } else {
483 /* 1170mV / 2^23 * 6 */
484 scale_uv = (1170ULL * 1000000000ULL * 6ULL);
485 }
486 break;
487 case IIO_TEMP:
488 /* 1170mV / 0.81 mV/C / 2^23 */
489 scale_uv = 1444444444444444ULL;
490 break;
491 default:
492 return -EINVAL;
493 }
494
495 scale_uv >>= (chan->scan_type.realbits - (unipolar ? 0 : 1));
496 *val = 0;
497 *val2 = scale_uv;
498 return IIO_VAL_INT_PLUS_NANO;
499 case IIO_CHAN_INFO_OFFSET:
500 if (!unipolar)
501 *val = -(1 << (chan->scan_type.realbits - 1));
502 else
503 *val = 0;
504
505 /* Kelvin to Celsius */
506 if (chan->type == IIO_TEMP) {
507 unsigned long long offset;
508 unsigned int shift;
509
510 shift = chan->scan_type.realbits - (unipolar ? 0 : 1);
511 offset = 273ULL << shift;
512 do_div(offset, 1444);
513 *val -= offset;
514 }
515 return IIO_VAL_INT;
516 }
517 return -EINVAL;
518 }
519
ad7793_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)520 static int ad7793_write_raw(struct iio_dev *indio_dev,
521 struct iio_chan_spec const *chan,
522 int val,
523 int val2,
524 long mask)
525 {
526 struct ad7793_state *st = iio_priv(indio_dev);
527 int ret, i;
528 unsigned int tmp;
529
530 mutex_lock(&indio_dev->mlock);
531 if (iio_buffer_enabled(indio_dev)) {
532 mutex_unlock(&indio_dev->mlock);
533 return -EBUSY;
534 }
535
536 switch (mask) {
537 case IIO_CHAN_INFO_SCALE:
538 ret = -EINVAL;
539 for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++)
540 if (val2 == st->scale_avail[i][1]) {
541 ret = 0;
542 tmp = st->conf;
543 st->conf &= ~AD7793_CONF_GAIN(-1);
544 st->conf |= AD7793_CONF_GAIN(i);
545
546 if (tmp == st->conf)
547 break;
548
549 ad_sd_write_reg(&st->sd, AD7793_REG_CONF,
550 sizeof(st->conf), st->conf);
551 ad7793_calibrate_all(st);
552 break;
553 }
554 break;
555 default:
556 ret = -EINVAL;
557 }
558
559 mutex_unlock(&indio_dev->mlock);
560 return ret;
561 }
562
ad7793_write_raw_get_fmt(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,long mask)563 static int ad7793_write_raw_get_fmt(struct iio_dev *indio_dev,
564 struct iio_chan_spec const *chan,
565 long mask)
566 {
567 return IIO_VAL_INT_PLUS_NANO;
568 }
569
570 static const struct iio_info ad7793_info = {
571 .read_raw = &ad7793_read_raw,
572 .write_raw = &ad7793_write_raw,
573 .write_raw_get_fmt = &ad7793_write_raw_get_fmt,
574 .attrs = &ad7793_attribute_group,
575 .validate_trigger = ad_sd_validate_trigger,
576 .driver_module = THIS_MODULE,
577 };
578
579 static const struct iio_info ad7797_info = {
580 .read_raw = &ad7793_read_raw,
581 .write_raw = &ad7793_write_raw,
582 .write_raw_get_fmt = &ad7793_write_raw_get_fmt,
583 .attrs = &ad7797_attribute_group,
584 .validate_trigger = ad_sd_validate_trigger,
585 .driver_module = THIS_MODULE,
586 };
587
588 #define DECLARE_AD7793_CHANNELS(_name, _b, _sb, _s) \
589 const struct iio_chan_spec _name##_channels[] = { \
590 AD_SD_DIFF_CHANNEL(0, 0, 0, AD7793_CH_AIN1P_AIN1M, (_b), (_sb), (_s)), \
591 AD_SD_DIFF_CHANNEL(1, 1, 1, AD7793_CH_AIN2P_AIN2M, (_b), (_sb), (_s)), \
592 AD_SD_DIFF_CHANNEL(2, 2, 2, AD7793_CH_AIN3P_AIN3M, (_b), (_sb), (_s)), \
593 AD_SD_SHORTED_CHANNEL(3, 0, AD7793_CH_AIN1M_AIN1M, (_b), (_sb), (_s)), \
594 AD_SD_TEMP_CHANNEL(4, AD7793_CH_TEMP, (_b), (_sb), (_s)), \
595 AD_SD_SUPPLY_CHANNEL(5, 3, AD7793_CH_AVDD_MONITOR, (_b), (_sb), (_s)), \
596 IIO_CHAN_SOFT_TIMESTAMP(6), \
597 }
598
599 #define DECLARE_AD7795_CHANNELS(_name, _b, _sb) \
600 const struct iio_chan_spec _name##_channels[] = { \
601 AD_SD_DIFF_CHANNEL(0, 0, 0, AD7793_CH_AIN1P_AIN1M, (_b), (_sb), 0), \
602 AD_SD_DIFF_CHANNEL(1, 1, 1, AD7793_CH_AIN2P_AIN2M, (_b), (_sb), 0), \
603 AD_SD_DIFF_CHANNEL(2, 2, 2, AD7793_CH_AIN3P_AIN3M, (_b), (_sb), 0), \
604 AD_SD_DIFF_CHANNEL(3, 3, 3, AD7795_CH_AIN4P_AIN4M, (_b), (_sb), 0), \
605 AD_SD_DIFF_CHANNEL(4, 4, 4, AD7795_CH_AIN5P_AIN5M, (_b), (_sb), 0), \
606 AD_SD_DIFF_CHANNEL(5, 5, 5, AD7795_CH_AIN6P_AIN6M, (_b), (_sb), 0), \
607 AD_SD_SHORTED_CHANNEL(6, 0, AD7795_CH_AIN1M_AIN1M, (_b), (_sb), 0), \
608 AD_SD_TEMP_CHANNEL(7, AD7793_CH_TEMP, (_b), (_sb), 0), \
609 AD_SD_SUPPLY_CHANNEL(8, 3, AD7793_CH_AVDD_MONITOR, (_b), (_sb), 0), \
610 IIO_CHAN_SOFT_TIMESTAMP(9), \
611 }
612
613 #define DECLARE_AD7797_CHANNELS(_name, _b, _sb) \
614 const struct iio_chan_spec _name##_channels[] = { \
615 AD_SD_DIFF_CHANNEL(0, 0, 0, AD7793_CH_AIN1P_AIN1M, (_b), (_sb), 0), \
616 AD_SD_SHORTED_CHANNEL(1, 0, AD7793_CH_AIN1M_AIN1M, (_b), (_sb), 0), \
617 AD_SD_TEMP_CHANNEL(2, AD7793_CH_TEMP, (_b), (_sb), 0), \
618 AD_SD_SUPPLY_CHANNEL(3, 3, AD7793_CH_AVDD_MONITOR, (_b), (_sb), 0), \
619 IIO_CHAN_SOFT_TIMESTAMP(4), \
620 }
621
622 #define DECLARE_AD7799_CHANNELS(_name, _b, _sb) \
623 const struct iio_chan_spec _name##_channels[] = { \
624 AD_SD_DIFF_CHANNEL(0, 0, 0, AD7793_CH_AIN1P_AIN1M, (_b), (_sb), 0), \
625 AD_SD_DIFF_CHANNEL(1, 1, 1, AD7793_CH_AIN2P_AIN2M, (_b), (_sb), 0), \
626 AD_SD_DIFF_CHANNEL(2, 2, 2, AD7793_CH_AIN3P_AIN3M, (_b), (_sb), 0), \
627 AD_SD_SHORTED_CHANNEL(3, 0, AD7793_CH_AIN1M_AIN1M, (_b), (_sb), 0), \
628 AD_SD_SUPPLY_CHANNEL(4, 3, AD7793_CH_AVDD_MONITOR, (_b), (_sb), 0), \
629 IIO_CHAN_SOFT_TIMESTAMP(5), \
630 }
631
632 static DECLARE_AD7793_CHANNELS(ad7785, 20, 32, 4);
633 static DECLARE_AD7793_CHANNELS(ad7792, 16, 32, 0);
634 static DECLARE_AD7793_CHANNELS(ad7793, 24, 32, 0);
635 static DECLARE_AD7795_CHANNELS(ad7794, 16, 32);
636 static DECLARE_AD7795_CHANNELS(ad7795, 24, 32);
637 static DECLARE_AD7797_CHANNELS(ad7796, 16, 16);
638 static DECLARE_AD7797_CHANNELS(ad7797, 24, 32);
639 static DECLARE_AD7799_CHANNELS(ad7798, 16, 16);
640 static DECLARE_AD7799_CHANNELS(ad7799, 24, 32);
641
642 static const struct ad7793_chip_info ad7793_chip_info_tbl[] = {
643 [ID_AD7785] = {
644 .id = AD7785_ID,
645 .channels = ad7785_channels,
646 .num_channels = ARRAY_SIZE(ad7785_channels),
647 .iio_info = &ad7793_info,
648 .sample_freq_avail = ad7793_sample_freq_avail,
649 .flags = AD7793_FLAG_HAS_CLKSEL |
650 AD7793_FLAG_HAS_REFSEL |
651 AD7793_FLAG_HAS_VBIAS |
652 AD7793_HAS_EXITATION_CURRENT |
653 AD7793_FLAG_HAS_GAIN |
654 AD7793_FLAG_HAS_BUFFER,
655 },
656 [ID_AD7792] = {
657 .id = AD7792_ID,
658 .channels = ad7792_channels,
659 .num_channels = ARRAY_SIZE(ad7792_channels),
660 .iio_info = &ad7793_info,
661 .sample_freq_avail = ad7793_sample_freq_avail,
662 .flags = AD7793_FLAG_HAS_CLKSEL |
663 AD7793_FLAG_HAS_REFSEL |
664 AD7793_FLAG_HAS_VBIAS |
665 AD7793_HAS_EXITATION_CURRENT |
666 AD7793_FLAG_HAS_GAIN |
667 AD7793_FLAG_HAS_BUFFER,
668 },
669 [ID_AD7793] = {
670 .id = AD7793_ID,
671 .channels = ad7793_channels,
672 .num_channels = ARRAY_SIZE(ad7793_channels),
673 .iio_info = &ad7793_info,
674 .sample_freq_avail = ad7793_sample_freq_avail,
675 .flags = AD7793_FLAG_HAS_CLKSEL |
676 AD7793_FLAG_HAS_REFSEL |
677 AD7793_FLAG_HAS_VBIAS |
678 AD7793_HAS_EXITATION_CURRENT |
679 AD7793_FLAG_HAS_GAIN |
680 AD7793_FLAG_HAS_BUFFER,
681 },
682 [ID_AD7794] = {
683 .id = AD7794_ID,
684 .channels = ad7794_channels,
685 .num_channels = ARRAY_SIZE(ad7794_channels),
686 .iio_info = &ad7793_info,
687 .sample_freq_avail = ad7793_sample_freq_avail,
688 .flags = AD7793_FLAG_HAS_CLKSEL |
689 AD7793_FLAG_HAS_REFSEL |
690 AD7793_FLAG_HAS_VBIAS |
691 AD7793_HAS_EXITATION_CURRENT |
692 AD7793_FLAG_HAS_GAIN |
693 AD7793_FLAG_HAS_BUFFER,
694 },
695 [ID_AD7795] = {
696 .id = AD7795_ID,
697 .channels = ad7795_channels,
698 .num_channels = ARRAY_SIZE(ad7795_channels),
699 .iio_info = &ad7793_info,
700 .sample_freq_avail = ad7793_sample_freq_avail,
701 .flags = AD7793_FLAG_HAS_CLKSEL |
702 AD7793_FLAG_HAS_REFSEL |
703 AD7793_FLAG_HAS_VBIAS |
704 AD7793_HAS_EXITATION_CURRENT |
705 AD7793_FLAG_HAS_GAIN |
706 AD7793_FLAG_HAS_BUFFER,
707 },
708 [ID_AD7796] = {
709 .id = AD7796_ID,
710 .channels = ad7796_channels,
711 .num_channels = ARRAY_SIZE(ad7796_channels),
712 .iio_info = &ad7797_info,
713 .sample_freq_avail = ad7797_sample_freq_avail,
714 .flags = AD7793_FLAG_HAS_CLKSEL,
715 },
716 [ID_AD7797] = {
717 .id = AD7797_ID,
718 .channels = ad7797_channels,
719 .num_channels = ARRAY_SIZE(ad7797_channels),
720 .iio_info = &ad7797_info,
721 .sample_freq_avail = ad7797_sample_freq_avail,
722 .flags = AD7793_FLAG_HAS_CLKSEL,
723 },
724 [ID_AD7798] = {
725 .id = AD7798_ID,
726 .channels = ad7798_channels,
727 .num_channels = ARRAY_SIZE(ad7798_channels),
728 .iio_info = &ad7793_info,
729 .sample_freq_avail = ad7793_sample_freq_avail,
730 .flags = AD7793_FLAG_HAS_GAIN |
731 AD7793_FLAG_HAS_BUFFER,
732 },
733 [ID_AD7799] = {
734 .id = AD7799_ID,
735 .channels = ad7799_channels,
736 .num_channels = ARRAY_SIZE(ad7799_channels),
737 .iio_info = &ad7793_info,
738 .sample_freq_avail = ad7793_sample_freq_avail,
739 .flags = AD7793_FLAG_HAS_GAIN |
740 AD7793_FLAG_HAS_BUFFER,
741 },
742 };
743
ad7793_probe(struct spi_device * spi)744 static int ad7793_probe(struct spi_device *spi)
745 {
746 const struct ad7793_platform_data *pdata = spi->dev.platform_data;
747 struct ad7793_state *st;
748 struct iio_dev *indio_dev;
749 int ret, vref_mv = 0;
750
751 if (!pdata) {
752 dev_err(&spi->dev, "no platform data?\n");
753 return -ENODEV;
754 }
755
756 if (!spi->irq) {
757 dev_err(&spi->dev, "no IRQ?\n");
758 return -ENODEV;
759 }
760
761 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
762 if (indio_dev == NULL)
763 return -ENOMEM;
764
765 st = iio_priv(indio_dev);
766
767 ad_sd_init(&st->sd, indio_dev, spi, &ad7793_sigma_delta_info);
768
769 if (pdata->refsel != AD7793_REFSEL_INTERNAL) {
770 st->reg = devm_regulator_get(&spi->dev, "refin");
771 if (IS_ERR(st->reg))
772 return PTR_ERR(st->reg);
773
774 ret = regulator_enable(st->reg);
775 if (ret)
776 return ret;
777
778 vref_mv = regulator_get_voltage(st->reg);
779 if (vref_mv < 0) {
780 ret = vref_mv;
781 goto error_disable_reg;
782 }
783
784 vref_mv /= 1000;
785 } else {
786 vref_mv = 1170; /* Build-in ref */
787 }
788
789 st->chip_info =
790 &ad7793_chip_info_tbl[spi_get_device_id(spi)->driver_data];
791
792 spi_set_drvdata(spi, indio_dev);
793
794 indio_dev->dev.parent = &spi->dev;
795 indio_dev->name = spi_get_device_id(spi)->name;
796 indio_dev->modes = INDIO_DIRECT_MODE;
797 indio_dev->channels = st->chip_info->channels;
798 indio_dev->num_channels = st->chip_info->num_channels;
799 indio_dev->info = st->chip_info->iio_info;
800
801 ret = ad_sd_setup_buffer_and_trigger(indio_dev);
802 if (ret)
803 goto error_disable_reg;
804
805 ret = ad7793_setup(indio_dev, pdata, vref_mv);
806 if (ret)
807 goto error_remove_trigger;
808
809 ret = iio_device_register(indio_dev);
810 if (ret)
811 goto error_remove_trigger;
812
813 return 0;
814
815 error_remove_trigger:
816 ad_sd_cleanup_buffer_and_trigger(indio_dev);
817 error_disable_reg:
818 if (pdata->refsel != AD7793_REFSEL_INTERNAL)
819 regulator_disable(st->reg);
820
821 return ret;
822 }
823
ad7793_remove(struct spi_device * spi)824 static int ad7793_remove(struct spi_device *spi)
825 {
826 const struct ad7793_platform_data *pdata = spi->dev.platform_data;
827 struct iio_dev *indio_dev = spi_get_drvdata(spi);
828 struct ad7793_state *st = iio_priv(indio_dev);
829
830 iio_device_unregister(indio_dev);
831 ad_sd_cleanup_buffer_and_trigger(indio_dev);
832
833 if (pdata->refsel != AD7793_REFSEL_INTERNAL)
834 regulator_disable(st->reg);
835
836 return 0;
837 }
838
839 static const struct spi_device_id ad7793_id[] = {
840 {"ad7785", ID_AD7785},
841 {"ad7792", ID_AD7792},
842 {"ad7793", ID_AD7793},
843 {"ad7794", ID_AD7794},
844 {"ad7795", ID_AD7795},
845 {"ad7796", ID_AD7796},
846 {"ad7797", ID_AD7797},
847 {"ad7798", ID_AD7798},
848 {"ad7799", ID_AD7799},
849 {}
850 };
851 MODULE_DEVICE_TABLE(spi, ad7793_id);
852
853 static struct spi_driver ad7793_driver = {
854 .driver = {
855 .name = "ad7793",
856 },
857 .probe = ad7793_probe,
858 .remove = ad7793_remove,
859 .id_table = ad7793_id,
860 };
861 module_spi_driver(ad7793_driver);
862
863 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
864 MODULE_DESCRIPTION("Analog Devices AD7793 and similar ADCs");
865 MODULE_LICENSE("GPL v2");
866