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drm/client: Fix drm client endless Kconfig loop
[drm/drm-misc.git] / drivers / iio / adc / ti-ads131e08.c
blob31f1f229d97a78ad9b3a7457ccfe42f34cdff94a
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Texas Instruments ADS131E0x 4-, 6- and 8-Channel ADCs
4 *
5 * Copyright (c) 2020 AVL DiTEST GmbH
6 * Tomislav Denis <tomislav.denis@avl.com>
7 *
8 * Datasheet: https://www.ti.com/lit/ds/symlink/ads131e08.pdf
9 */
10
11 #include <linux/bitfield.h>
12 #include <linux/clk.h>
13 #include <linux/delay.h>
14 #include <linux/module.h>
15
16 #include <linux/iio/buffer.h>
17 #include <linux/iio/iio.h>
18 #include <linux/iio/sysfs.h>
19 #include <linux/iio/trigger.h>
20 #include <linux/iio/trigger_consumer.h>
21 #include <linux/iio/triggered_buffer.h>
22
23 #include <linux/regulator/consumer.h>
24 #include <linux/spi/spi.h>
25
26 #include <linux/unaligned.h>
27
28 /* Commands */
29 #define ADS131E08_CMD_RESET 0x06
30 #define ADS131E08_CMD_START 0x08
31 #define ADS131E08_CMD_STOP 0x0A
32 #define ADS131E08_CMD_OFFSETCAL 0x1A
33 #define ADS131E08_CMD_SDATAC 0x11
34 #define ADS131E08_CMD_RDATA 0x12
35 #define ADS131E08_CMD_RREG(r) (BIT(5) | (r & GENMASK(4, 0)))
36 #define ADS131E08_CMD_WREG(r) (BIT(6) | (r & GENMASK(4, 0)))
37
38 /* Registers */
39 #define ADS131E08_ADR_CFG1R 0x01
40 #define ADS131E08_ADR_CFG3R 0x03
41 #define ADS131E08_ADR_CH0R 0x05
42
43 /* Configuration register 1 */
44 #define ADS131E08_CFG1R_DR_MASK GENMASK(2, 0)
45
46 /* Configuration register 3 */
47 #define ADS131E08_CFG3R_PDB_REFBUF_MASK BIT(7)
48 #define ADS131E08_CFG3R_VREF_4V_MASK BIT(5)
49
50 /* Channel settings register */
51 #define ADS131E08_CHR_GAIN_MASK GENMASK(6, 4)
52 #define ADS131E08_CHR_MUX_MASK GENMASK(2, 0)
53 #define ADS131E08_CHR_PWD_MASK BIT(7)
54
55 /* ADC misc */
56 #define ADS131E08_DEFAULT_DATA_RATE 1
57 #define ADS131E08_DEFAULT_PGA_GAIN 1
58 #define ADS131E08_DEFAULT_MUX 0
59
60 #define ADS131E08_VREF_2V4_mV 2400
61 #define ADS131E08_VREF_4V_mV 4000
62
63 #define ADS131E08_WAIT_RESET_CYCLES 18
64 #define ADS131E08_WAIT_SDECODE_CYCLES 4
65 #define ADS131E08_WAIT_OFFSETCAL_MS 153
66 #define ADS131E08_MAX_SETTLING_TIME_MS 6
67
68 #define ADS131E08_NUM_STATUS_BYTES 3
69 #define ADS131E08_NUM_DATA_BYTES_MAX 24
70 #define ADS131E08_NUM_DATA_BYTES(dr) (((dr) >= 32) ? 2 : 3)
71 #define ADS131E08_NUM_DATA_BITS(dr) (ADS131E08_NUM_DATA_BYTES(dr) * 8)
72 #define ADS131E08_NUM_STORAGE_BYTES 4
73
74 enum ads131e08_ids {
75 ads131e04,
76 ads131e06,
77 ads131e08,
78 };
79
80 struct ads131e08_info {
81 unsigned int max_channels;
82 const char *name;
83 };
84
85 struct ads131e08_channel_config {
86 unsigned int pga_gain;
87 unsigned int mux;
88 };
89
90 struct ads131e08_state {
91 const struct ads131e08_info *info;
92 struct spi_device *spi;
93 struct iio_trigger *trig;
94 struct clk *adc_clk;
95 struct regulator *vref_reg;
96 struct ads131e08_channel_config *channel_config;
97 unsigned int data_rate;
98 unsigned int vref_mv;
99 unsigned int sdecode_delay_us;
100 unsigned int reset_delay_us;
101 unsigned int readback_len;
102 struct completion completion;
103 struct {
104 u8 data[ADS131E08_NUM_DATA_BYTES_MAX];
105 s64 ts __aligned(8);
106 } tmp_buf;
107
108 u8 tx_buf[3] __aligned(IIO_DMA_MINALIGN);
109 /*
110 * Add extra one padding byte to be able to access the last channel
111 * value using u32 pointer
112 */
113 u8 rx_buf[ADS131E08_NUM_STATUS_BYTES +
114 ADS131E08_NUM_DATA_BYTES_MAX + 1];
115 };
116
117 static const struct ads131e08_info ads131e08_info_tbl[] = {
118 [ads131e04] = {
119 .max_channels = 4,
120 .name = "ads131e04",
121 },
122 [ads131e06] = {
123 .max_channels = 6,
124 .name = "ads131e06",
125 },
126 [ads131e08] = {
127 .max_channels = 8,
128 .name = "ads131e08",
129 },
130 };
131
132 struct ads131e08_data_rate_desc {
133 unsigned int rate; /* data rate in kSPS */
134 u8 reg; /* reg value */
135 };
136
137 static const struct ads131e08_data_rate_desc ads131e08_data_rate_tbl[] = {
138 { .rate = 64, .reg = 0x00 },
139 { .rate = 32, .reg = 0x01 },
140 { .rate = 16, .reg = 0x02 },
141 { .rate = 8, .reg = 0x03 },
142 { .rate = 4, .reg = 0x04 },
143 { .rate = 2, .reg = 0x05 },
144 { .rate = 1, .reg = 0x06 },
145 };
146
147 struct ads131e08_pga_gain_desc {
148 unsigned int gain; /* PGA gain value */
149 u8 reg; /* field value */
150 };
151
152 static const struct ads131e08_pga_gain_desc ads131e08_pga_gain_tbl[] = {
153 { .gain = 1, .reg = 0x01 },
154 { .gain = 2, .reg = 0x02 },
155 { .gain = 4, .reg = 0x04 },
156 { .gain = 8, .reg = 0x05 },
157 { .gain = 12, .reg = 0x06 },
158 };
159
160 static const u8 ads131e08_valid_channel_mux_values[] = { 0, 1, 3, 4 };
161
162 static int ads131e08_exec_cmd(struct ads131e08_state *st, u8 cmd)
163 {
164 int ret;
165
166 ret = spi_write_then_read(st->spi, &cmd, 1, NULL, 0);
167 if (ret)
168 dev_err(&st->spi->dev, "Exec cmd(%02x) failed\n", cmd);
169
170 return ret;
171 }
172
173 static int ads131e08_read_reg(struct ads131e08_state *st, u8 reg)
174 {
175 int ret;
176 struct spi_transfer transfer[] = {
177 {
178 .tx_buf = &st->tx_buf,
179 .len = 2,
180 .delay = {
181 .value = st->sdecode_delay_us,
182 .unit = SPI_DELAY_UNIT_USECS,
183 },
184 }, {
185 .rx_buf = &st->rx_buf,
186 .len = 1,
187 },
188 };
189
190 st->tx_buf[0] = ADS131E08_CMD_RREG(reg);
191 st->tx_buf[1] = 0;
192
193 ret = spi_sync_transfer(st->spi, transfer, ARRAY_SIZE(transfer));
194 if (ret) {
195 dev_err(&st->spi->dev, "Read register failed\n");
196 return ret;
197 }
198
199 return st->rx_buf[0];
200 }
201
202 static int ads131e08_write_reg(struct ads131e08_state *st, u8 reg, u8 value)
203 {
204 int ret;
205 struct spi_transfer transfer[] = {
206 {
207 .tx_buf = &st->tx_buf,
208 .len = 3,
209 .delay = {
210 .value = st->sdecode_delay_us,
211 .unit = SPI_DELAY_UNIT_USECS,
212 },
213 }
214 };
215
216 st->tx_buf[0] = ADS131E08_CMD_WREG(reg);
217 st->tx_buf[1] = 0;
218 st->tx_buf[2] = value;
219
220 ret = spi_sync_transfer(st->spi, transfer, ARRAY_SIZE(transfer));
221 if (ret)
222 dev_err(&st->spi->dev, "Write register failed\n");
223
224 return ret;
225 }
226
227 static int ads131e08_read_data(struct ads131e08_state *st, int rx_len)
228 {
229 int ret;
230 struct spi_transfer transfer[] = {
231 {
232 .tx_buf = &st->tx_buf,
233 .len = 1,
234 }, {
235 .rx_buf = &st->rx_buf,
236 .len = rx_len,
237 },
238 };
239
240 st->tx_buf[0] = ADS131E08_CMD_RDATA;
241
242 ret = spi_sync_transfer(st->spi, transfer, ARRAY_SIZE(transfer));
243 if (ret)
244 dev_err(&st->spi->dev, "Read data failed\n");
245
246 return ret;
247 }
248
249 static int ads131e08_set_data_rate(struct ads131e08_state *st, int data_rate)
250 {
251 int i, reg, ret;
252
253 for (i = 0; i < ARRAY_SIZE(ads131e08_data_rate_tbl); i++) {
254 if (ads131e08_data_rate_tbl[i].rate == data_rate)
255 break;
256 }
257
258 if (i == ARRAY_SIZE(ads131e08_data_rate_tbl)) {
259 dev_err(&st->spi->dev, "invalid data rate value\n");
260 return -EINVAL;
261 }
262
263 reg = ads131e08_read_reg(st, ADS131E08_ADR_CFG1R);
264 if (reg < 0)
265 return reg;
266
267 reg &= ~ADS131E08_CFG1R_DR_MASK;
268 reg |= FIELD_PREP(ADS131E08_CFG1R_DR_MASK,
269 ads131e08_data_rate_tbl[i].reg);
270
271 ret = ads131e08_write_reg(st, ADS131E08_ADR_CFG1R, reg);
272 if (ret)
273 return ret;
274
275 st->data_rate = data_rate;
276 st->readback_len = ADS131E08_NUM_STATUS_BYTES +
277 ADS131E08_NUM_DATA_BYTES(st->data_rate) *
278 st->info->max_channels;
279
280 return 0;
281 }
282
283 static int ads131e08_pga_gain_to_field_value(struct ads131e08_state *st,
284 unsigned int pga_gain)
285 {
286 int i;
287
288 for (i = 0; i < ARRAY_SIZE(ads131e08_pga_gain_tbl); i++) {
289 if (ads131e08_pga_gain_tbl[i].gain == pga_gain)
290 break;
291 }
292
293 if (i == ARRAY_SIZE(ads131e08_pga_gain_tbl)) {
294 dev_err(&st->spi->dev, "invalid PGA gain value\n");
295 return -EINVAL;
296 }
297
298 return ads131e08_pga_gain_tbl[i].reg;
299 }
300
301 static int ads131e08_set_pga_gain(struct ads131e08_state *st,
302 unsigned int channel, unsigned int pga_gain)
303 {
304 int field_value, reg;
305
306 field_value = ads131e08_pga_gain_to_field_value(st, pga_gain);
307 if (field_value < 0)
308 return field_value;
309
310 reg = ads131e08_read_reg(st, ADS131E08_ADR_CH0R + channel);
311 if (reg < 0)
312 return reg;
313
314 reg &= ~ADS131E08_CHR_GAIN_MASK;
315 reg |= FIELD_PREP(ADS131E08_CHR_GAIN_MASK, field_value);
316
317 return ads131e08_write_reg(st, ADS131E08_ADR_CH0R + channel, reg);
318 }
319
320 static int ads131e08_validate_channel_mux(struct ads131e08_state *st,
321 unsigned int mux)
322 {
323 int i;
324
325 for (i = 0; i < ARRAY_SIZE(ads131e08_valid_channel_mux_values); i++) {
326 if (ads131e08_valid_channel_mux_values[i] == mux)
327 break;
328 }
329
330 if (i == ARRAY_SIZE(ads131e08_valid_channel_mux_values)) {
331 dev_err(&st->spi->dev, "invalid channel mux value\n");
332 return -EINVAL;
333 }
334
335 return 0;
336 }
337
338 static int ads131e08_set_channel_mux(struct ads131e08_state *st,
339 unsigned int channel, unsigned int mux)
340 {
341 int reg;
342
343 reg = ads131e08_read_reg(st, ADS131E08_ADR_CH0R + channel);
344 if (reg < 0)
345 return reg;
346
347 reg &= ~ADS131E08_CHR_MUX_MASK;
348 reg |= FIELD_PREP(ADS131E08_CHR_MUX_MASK, mux);
349
350 return ads131e08_write_reg(st, ADS131E08_ADR_CH0R + channel, reg);
351 }
352
353 static int ads131e08_power_down_channel(struct ads131e08_state *st,
354 unsigned int channel, bool value)
355 {
356 int reg;
357
358 reg = ads131e08_read_reg(st, ADS131E08_ADR_CH0R + channel);
359 if (reg < 0)
360 return reg;
361
362 reg &= ~ADS131E08_CHR_PWD_MASK;
363 reg |= FIELD_PREP(ADS131E08_CHR_PWD_MASK, value);
364
365 return ads131e08_write_reg(st, ADS131E08_ADR_CH0R + channel, reg);
366 }
367
368 static int ads131e08_config_reference_voltage(struct ads131e08_state *st)
369 {
370 int reg;
371
372 reg = ads131e08_read_reg(st, ADS131E08_ADR_CFG3R);
373 if (reg < 0)
374 return reg;
375
376 reg &= ~ADS131E08_CFG3R_PDB_REFBUF_MASK;
377 if (!st->vref_reg) {
378 reg |= FIELD_PREP(ADS131E08_CFG3R_PDB_REFBUF_MASK, 1);
379 reg &= ~ADS131E08_CFG3R_VREF_4V_MASK;
380 reg |= FIELD_PREP(ADS131E08_CFG3R_VREF_4V_MASK,
381 st->vref_mv == ADS131E08_VREF_4V_mV);
382 }
383
384 return ads131e08_write_reg(st, ADS131E08_ADR_CFG3R, reg);
385 }
386
387 static int ads131e08_initial_config(struct iio_dev *indio_dev)
388 {
389 const struct iio_chan_spec *channel = indio_dev->channels;
390 struct ads131e08_state *st = iio_priv(indio_dev);
391 unsigned long active_channels = 0;
392 int ret, i;
393
394 ret = ads131e08_exec_cmd(st, ADS131E08_CMD_RESET);
395 if (ret)
396 return ret;
397
398 udelay(st->reset_delay_us);
399
400 /* Disable read data in continuous mode (enabled by default) */
401 ret = ads131e08_exec_cmd(st, ADS131E08_CMD_SDATAC);
402 if (ret)
403 return ret;
404
405 ret = ads131e08_set_data_rate(st, ADS131E08_DEFAULT_DATA_RATE);
406 if (ret)
407 return ret;
408
409 ret = ads131e08_config_reference_voltage(st);
410 if (ret)
411 return ret;
412
413 for (i = 0; i < indio_dev->num_channels; i++) {
414 ret = ads131e08_set_pga_gain(st, channel->channel,
415 st->channel_config[i].pga_gain);
416 if (ret)
417 return ret;
418
419 ret = ads131e08_set_channel_mux(st, channel->channel,
420 st->channel_config[i].mux);
421 if (ret)
422 return ret;
423
424 active_channels |= BIT(channel->channel);
425 channel++;
426 }
427
428 /* Power down unused channels */
429 for_each_clear_bit(i, &active_channels, st->info->max_channels) {
430 ret = ads131e08_power_down_channel(st, i, true);
431 if (ret)
432 return ret;
433 }
434
435 /* Request channel offset calibration */
436 ret = ads131e08_exec_cmd(st, ADS131E08_CMD_OFFSETCAL);
437 if (ret)
438 return ret;
439
440 /*
441 * Channel offset calibration is triggered with the first START
442 * command. Since calibration takes more time than settling operation,
443 * this causes timeout error when command START is sent first
444 * time (e.g. first call of the ads131e08_read_direct method).
445 * To avoid this problem offset calibration is triggered here.
446 */
447 ret = ads131e08_exec_cmd(st, ADS131E08_CMD_START);
448 if (ret)
449 return ret;
450
451 msleep(ADS131E08_WAIT_OFFSETCAL_MS);
452
453 return ads131e08_exec_cmd(st, ADS131E08_CMD_STOP);
454 }
455
456 static int ads131e08_pool_data(struct ads131e08_state *st)
457 {
458 unsigned long timeout;
459 int ret;
460
461 reinit_completion(&st->completion);
462
463 ret = ads131e08_exec_cmd(st, ADS131E08_CMD_START);
464 if (ret)
465 return ret;
466
467 timeout = msecs_to_jiffies(ADS131E08_MAX_SETTLING_TIME_MS);
468 ret = wait_for_completion_timeout(&st->completion, timeout);
469 if (!ret)
470 return -ETIMEDOUT;
471
472 ret = ads131e08_read_data(st, st->readback_len);
473 if (ret)
474 return ret;
475
476 return ads131e08_exec_cmd(st, ADS131E08_CMD_STOP);
477 }
478
479 static int ads131e08_read_direct(struct iio_dev *indio_dev,
480 struct iio_chan_spec const *channel, int *value)
481 {
482 struct ads131e08_state *st = iio_priv(indio_dev);
483 u8 num_bits, *src;
484 int ret;
485
486 ret = ads131e08_pool_data(st);
487 if (ret)
488 return ret;
489
490 src = st->rx_buf + ADS131E08_NUM_STATUS_BYTES +
491 channel->channel * ADS131E08_NUM_DATA_BYTES(st->data_rate);
492
493 num_bits = ADS131E08_NUM_DATA_BITS(st->data_rate);
494 *value = sign_extend32(get_unaligned_be32(src) >> (32 - num_bits), num_bits - 1);
495
496 return 0;
497 }
498
499 static int ads131e08_read_raw(struct iio_dev *indio_dev,
500 struct iio_chan_spec const *channel, int *value,
501 int *value2, long mask)
502 {
503 struct ads131e08_state *st = iio_priv(indio_dev);
504 int ret;
505
506 switch (mask) {
507 case IIO_CHAN_INFO_RAW:
508 ret = iio_device_claim_direct_mode(indio_dev);
509 if (ret)
510 return ret;
511
512 ret = ads131e08_read_direct(indio_dev, channel, value);
513 iio_device_release_direct_mode(indio_dev);
514 if (ret)
515 return ret;
516
517 return IIO_VAL_INT;
518
519 case IIO_CHAN_INFO_SCALE:
520 if (st->vref_reg) {
521 ret = regulator_get_voltage(st->vref_reg);
522 if (ret < 0)
523 return ret;
524
525 *value = ret / 1000;
526 } else {
527 *value = st->vref_mv;
528 }
529
530 *value /= st->channel_config[channel->address].pga_gain;
531 *value2 = ADS131E08_NUM_DATA_BITS(st->data_rate) - 1;
532
533 return IIO_VAL_FRACTIONAL_LOG2;
534
535 case IIO_CHAN_INFO_SAMP_FREQ:
536 *value = st->data_rate;
537
538 return IIO_VAL_INT;
539
540 default:
541 return -EINVAL;
542 }
543 }
544
545 static int ads131e08_write_raw(struct iio_dev *indio_dev,
546 struct iio_chan_spec const *channel, int value,
547 int value2, long mask)
548 {
549 struct ads131e08_state *st = iio_priv(indio_dev);
550 int ret;
551
552 switch (mask) {
553 case IIO_CHAN_INFO_SAMP_FREQ:
554 ret = iio_device_claim_direct_mode(indio_dev);
555 if (ret)
556 return ret;
557
558 ret = ads131e08_set_data_rate(st, value);
559 iio_device_release_direct_mode(indio_dev);
560 return ret;
561
562 default:
563 return -EINVAL;
564 }
565 }
566
567 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("1 2 4 8 16 32 64");
568
569 static struct attribute *ads131e08_attributes[] = {
570 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
571 NULL
572 };
573
574 static const struct attribute_group ads131e08_attribute_group = {
575 .attrs = ads131e08_attributes,
576 };
577
578 static int ads131e08_debugfs_reg_access(struct iio_dev *indio_dev,
579 unsigned int reg, unsigned int writeval, unsigned int *readval)
580 {
581 struct ads131e08_state *st = iio_priv(indio_dev);
582
583 if (readval) {
584 int ret = ads131e08_read_reg(st, reg);
585 *readval = ret;
586 return ret;
587 }
588
589 return ads131e08_write_reg(st, reg, writeval);
590 }
591
592 static const struct iio_info ads131e08_iio_info = {
593 .read_raw = ads131e08_read_raw,
594 .write_raw = ads131e08_write_raw,
595 .attrs = &ads131e08_attribute_group,
596 .debugfs_reg_access = &ads131e08_debugfs_reg_access,
597 };
598
599 static int ads131e08_set_trigger_state(struct iio_trigger *trig, bool state)
600 {
601 struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
602 struct ads131e08_state *st = iio_priv(indio_dev);
603 u8 cmd = state ? ADS131E08_CMD_START : ADS131E08_CMD_STOP;
604
605 return ads131e08_exec_cmd(st, cmd);
606 }
607
608 static const struct iio_trigger_ops ads131e08_trigger_ops = {
609 .set_trigger_state = &ads131e08_set_trigger_state,
610 .validate_device = &iio_trigger_validate_own_device,
611 };
612
613 static irqreturn_t ads131e08_trigger_handler(int irq, void *private)
614 {
615 struct iio_poll_func *pf = private;
616 struct iio_dev *indio_dev = pf->indio_dev;
617 struct ads131e08_state *st = iio_priv(indio_dev);
618 unsigned int chn, i = 0;
619 u8 *src, *dest;
620 int ret;
621
622 /*
623 * The number of data bits per channel depends on the data rate.
624 * For 32 and 64 ksps data rates, number of data bits per channel
625 * is 16. This case is not compliant with used (fixed) scan element
626 * type (be:s24/32>>8). So we use a little tweak to pack properly
627 * 16 bits of data into the buffer.
628 */
629 unsigned int num_bytes = ADS131E08_NUM_DATA_BYTES(st->data_rate);
630 u8 tweek_offset = num_bytes == 2 ? 1 : 0;
631
632 if (iio_trigger_using_own(indio_dev))
633 ret = ads131e08_read_data(st, st->readback_len);
634 else
635 ret = ads131e08_pool_data(st);
636
637 if (ret)
638 goto out;
639
640 iio_for_each_active_channel(indio_dev, chn) {
641 src = st->rx_buf + ADS131E08_NUM_STATUS_BYTES + chn * num_bytes;
642 dest = st->tmp_buf.data + i * ADS131E08_NUM_STORAGE_BYTES;
643
644 /*
645 * Tweek offset is 0:
646 * +---+---+---+---+
647 * |D0 |D1 |D2 | X | (3 data bytes)
648 * +---+---+---+---+
649 * a+0 a+1 a+2 a+3
650 *
651 * Tweek offset is 1:
652 * +---+---+---+---+
653 * |P0 |D0 |D1 | X | (one padding byte and 2 data bytes)
654 * +---+---+---+---+
655 * a+0 a+1 a+2 a+3
656 */
657 memcpy(dest + tweek_offset, src, num_bytes);
658
659 /*
660 * Data conversion from 16 bits of data to 24 bits of data
661 * is done by sign extension (properly filling padding byte).
662 */
663 if (tweek_offset)
664 *dest = *src & BIT(7) ? 0xff : 0x00;
665
666 i++;
667 }
668
669 iio_push_to_buffers_with_timestamp(indio_dev, st->tmp_buf.data,
670 iio_get_time_ns(indio_dev));
671
672 out:
673 iio_trigger_notify_done(indio_dev->trig);
674
675 return IRQ_HANDLED;
676 }
677
678 static irqreturn_t ads131e08_interrupt(int irq, void *private)
679 {
680 struct iio_dev *indio_dev = private;
681 struct ads131e08_state *st = iio_priv(indio_dev);
682
683 if (iio_buffer_enabled(indio_dev) && iio_trigger_using_own(indio_dev))
684 iio_trigger_poll(st->trig);
685 else
686 complete(&st->completion);
687
688 return IRQ_HANDLED;
689 }
690
691 static int ads131e08_alloc_channels(struct iio_dev *indio_dev)
692 {
693 struct ads131e08_state *st = iio_priv(indio_dev);
694 struct ads131e08_channel_config *channel_config;
695 struct device *dev = &st->spi->dev;
696 struct iio_chan_spec *channels;
697 unsigned int channel, tmp;
698 int num_channels, i, ret;
699
700 ret = device_property_read_u32(dev, "ti,vref-internal", &tmp);
701 if (ret)
702 tmp = 0;
703
704 switch (tmp) {
705 case 0:
706 st->vref_mv = ADS131E08_VREF_2V4_mV;
707 break;
708 case 1:
709 st->vref_mv = ADS131E08_VREF_4V_mV;
710 break;
711 default:
712 dev_err(&st->spi->dev, "invalid internal voltage reference\n");
713 return -EINVAL;
714 }
715
716 num_channels = device_get_child_node_count(dev);
717 if (num_channels == 0) {
718 dev_err(&st->spi->dev, "no channel children\n");
719 return -ENODEV;
720 }
721
722 if (num_channels > st->info->max_channels) {
723 dev_err(&st->spi->dev, "num of channel children out of range\n");
724 return -EINVAL;
725 }
726
727 channels = devm_kcalloc(&st->spi->dev, num_channels,
728 sizeof(*channels), GFP_KERNEL);
729 if (!channels)
730 return -ENOMEM;
731
732 channel_config = devm_kcalloc(&st->spi->dev, num_channels,
733 sizeof(*channel_config), GFP_KERNEL);
734 if (!channel_config)
735 return -ENOMEM;
736
737 i = 0;
738 device_for_each_child_node_scoped(dev, node) {
739 ret = fwnode_property_read_u32(node, "reg", &channel);
740 if (ret)
741 return ret;
742
743 ret = fwnode_property_read_u32(node, "ti,gain", &tmp);
744 if (ret) {
745 channel_config[i].pga_gain = ADS131E08_DEFAULT_PGA_GAIN;
746 } else {
747 ret = ads131e08_pga_gain_to_field_value(st, tmp);
748 if (ret < 0)
749 return ret;
750
751 channel_config[i].pga_gain = tmp;
752 }
753
754 ret = fwnode_property_read_u32(node, "ti,mux", &tmp);
755 if (ret) {
756 channel_config[i].mux = ADS131E08_DEFAULT_MUX;
757 } else {
758 ret = ads131e08_validate_channel_mux(st, tmp);
759 if (ret)
760 return ret;
761
762 channel_config[i].mux = tmp;
763 }
764
765 channels[i].type = IIO_VOLTAGE;
766 channels[i].indexed = 1;
767 channels[i].channel = channel;
768 channels[i].address = i;
769 channels[i].info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
770 BIT(IIO_CHAN_INFO_SCALE);
771 channels[i].info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ);
772 channels[i].scan_index = channel;
773 channels[i].scan_type.sign = 's';
774 channels[i].scan_type.realbits = 24;
775 channels[i].scan_type.storagebits = 32;
776 channels[i].scan_type.shift = 8;
777 channels[i].scan_type.endianness = IIO_BE;
778 i++;
779 }
780
781 indio_dev->channels = channels;
782 indio_dev->num_channels = num_channels;
783 st->channel_config = channel_config;
784
785 return 0;
786
787 }
788
789 static void ads131e08_regulator_disable(void *data)
790 {
791 struct ads131e08_state *st = data;
792
793 regulator_disable(st->vref_reg);
794 }
795
796 static int ads131e08_probe(struct spi_device *spi)
797 {
798 const struct ads131e08_info *info;
799 struct ads131e08_state *st;
800 struct iio_dev *indio_dev;
801 unsigned long adc_clk_hz;
802 unsigned long adc_clk_ns;
803 int ret;
804
805 info = spi_get_device_match_data(spi);
806 if (!info) {
807 dev_err(&spi->dev, "failed to get match data\n");
808 return -ENODEV;
809 }
810
811 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
812 if (!indio_dev) {
813 dev_err(&spi->dev, "failed to allocate IIO device\n");
814 return -ENOMEM;
815 }
816
817 st = iio_priv(indio_dev);
818 st->info = info;
819 st->spi = spi;
820
821 ret = ads131e08_alloc_channels(indio_dev);
822 if (ret)
823 return ret;
824
825 indio_dev->name = st->info->name;
826 indio_dev->info = &ads131e08_iio_info;
827 indio_dev->modes = INDIO_DIRECT_MODE;
828
829 init_completion(&st->completion);
830
831 if (spi->irq) {
832 ret = devm_request_irq(&spi->dev, spi->irq,
833 ads131e08_interrupt,
834 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
835 spi->dev.driver->name, indio_dev);
836 if (ret)
837 return dev_err_probe(&spi->dev, ret,
838 "request irq failed\n");
839 } else {
840 dev_err(&spi->dev, "data ready IRQ missing\n");
841 return -ENODEV;
842 }
843
844 st->trig = devm_iio_trigger_alloc(&spi->dev, "%s-dev%d",
845 indio_dev->name, iio_device_id(indio_dev));
846 if (!st->trig) {
847 dev_err(&spi->dev, "failed to allocate IIO trigger\n");
848 return -ENOMEM;
849 }
850
851 st->trig->ops = &ads131e08_trigger_ops;
852 st->trig->dev.parent = &spi->dev;
853 iio_trigger_set_drvdata(st->trig, indio_dev);
854 ret = devm_iio_trigger_register(&spi->dev, st->trig);
855 if (ret) {
856 dev_err(&spi->dev, "failed to register IIO trigger\n");
857 return -ENOMEM;
858 }
859
860 indio_dev->trig = iio_trigger_get(st->trig);
861
862 ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
863 NULL, &ads131e08_trigger_handler, NULL);
864 if (ret) {
865 dev_err(&spi->dev, "failed to setup IIO buffer\n");
866 return ret;
867 }
868
869 st->vref_reg = devm_regulator_get_optional(&spi->dev, "vref");
870 if (!IS_ERR(st->vref_reg)) {
871 ret = regulator_enable(st->vref_reg);
872 if (ret) {
873 dev_err(&spi->dev,
874 "failed to enable external vref supply\n");
875 return ret;
876 }
877
878 ret = devm_add_action_or_reset(&spi->dev, ads131e08_regulator_disable, st);
879 if (ret)
880 return ret;
881 } else {
882 if (PTR_ERR(st->vref_reg) != -ENODEV)
883 return PTR_ERR(st->vref_reg);
884
885 st->vref_reg = NULL;
886 }
887
888 st->adc_clk = devm_clk_get_enabled(&spi->dev, "adc-clk");
889 if (IS_ERR(st->adc_clk))
890 return dev_err_probe(&spi->dev, PTR_ERR(st->adc_clk),
891 "failed to get the ADC clock\n");
892
893 adc_clk_hz = clk_get_rate(st->adc_clk);
894 if (!adc_clk_hz) {
895 dev_err(&spi->dev, "failed to get the ADC clock rate\n");
896 return -EINVAL;
897 }
898
899 adc_clk_ns = NSEC_PER_SEC / adc_clk_hz;
900 st->sdecode_delay_us = DIV_ROUND_UP(
901 ADS131E08_WAIT_SDECODE_CYCLES * adc_clk_ns, NSEC_PER_USEC);
902 st->reset_delay_us = DIV_ROUND_UP(
903 ADS131E08_WAIT_RESET_CYCLES * adc_clk_ns, NSEC_PER_USEC);
904
905 ret = ads131e08_initial_config(indio_dev);
906 if (ret) {
907 dev_err(&spi->dev, "initial configuration failed\n");
908 return ret;
909 }
910
911 return devm_iio_device_register(&spi->dev, indio_dev);
912 }
913
914 static const struct of_device_id ads131e08_of_match[] = {
915 { .compatible = "ti,ads131e04",
916 .data = &ads131e08_info_tbl[ads131e04], },
917 { .compatible = "ti,ads131e06",
918 .data = &ads131e08_info_tbl[ads131e06], },
919 { .compatible = "ti,ads131e08",
920 .data = &ads131e08_info_tbl[ads131e08], },
921 { }
922 };
923 MODULE_DEVICE_TABLE(of, ads131e08_of_match);
924
925 static const struct spi_device_id ads131e08_ids[] = {
926 { "ads131e04", (kernel_ulong_t)&ads131e08_info_tbl[ads131e04] },
927 { "ads131e06", (kernel_ulong_t)&ads131e08_info_tbl[ads131e06] },
928 { "ads131e08", (kernel_ulong_t)&ads131e08_info_tbl[ads131e08] },
929 { }
930 };
931 MODULE_DEVICE_TABLE(spi, ads131e08_ids);
932
933 static struct spi_driver ads131e08_driver = {
934 .driver = {
935 .name = "ads131e08",
936 .of_match_table = ads131e08_of_match,
937 },
938 .probe = ads131e08_probe,
939 .id_table = ads131e08_ids,
940 };
941 module_spi_driver(ads131e08_driver);
942
943 MODULE_AUTHOR("Tomislav Denis <tomislav.denis@avl.com>");
944 MODULE_DESCRIPTION("Driver for ADS131E0x ADC family");
945 MODULE_LICENSE("GPL v2");
Kernel DRM miscellaneous fixes and cross-tree changes