1 /*
2 * AD7190 AD7192 AD7195 SPI ADC driver
3 *
4 * Copyright 2011 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
20 #include "../iio.h"
21 #include "../sysfs.h"
22 #include "../buffer.h"
23 #include "../ring_sw.h"
24 #include "../trigger.h"
25 #include "../trigger_consumer.h"
26
27 #include "ad7192.h"
28
29 /* Registers */
30 #define AD7192_REG_COMM 0 /* Communications Register (WO, 8-bit) */
31 #define AD7192_REG_STAT 0 /* Status Register (RO, 8-bit) */
32 #define AD7192_REG_MODE 1 /* Mode Register (RW, 24-bit */
33 #define AD7192_REG_CONF 2 /* Configuration Register (RW, 24-bit) */
34 #define AD7192_REG_DATA 3 /* Data Register (RO, 24/32-bit) */
35 #define AD7192_REG_ID 4 /* ID Register (RO, 8-bit) */
36 #define AD7192_REG_GPOCON 5 /* GPOCON Register (RO, 8-bit) */
37 #define AD7192_REG_OFFSET 6 /* Offset Register (RW, 16-bit
38 * (AD7792)/24-bit (AD7192)) */
39 #define AD7192_REG_FULLSALE 7 /* Full-Scale Register
40 * (RW, 16-bit (AD7792)/24-bit (AD7192)) */
41
42 /* Communications Register Bit Designations (AD7192_REG_COMM) */
43 #define AD7192_COMM_WEN (1 << 7) /* Write Enable */
44 #define AD7192_COMM_WRITE (0 << 6) /* Write Operation */
45 #define AD7192_COMM_READ (1 << 6) /* Read Operation */
46 #define AD7192_COMM_ADDR(x) (((x) & 0x7) << 3) /* Register Address */
47 #define AD7192_COMM_CREAD (1 << 2) /* Continuous Read of Data Register */
48
49 /* Status Register Bit Designations (AD7192_REG_STAT) */
50 #define AD7192_STAT_RDY (1 << 7) /* Ready */
51 #define AD7192_STAT_ERR (1 << 6) /* Error (Overrange, Underrange) */
52 #define AD7192_STAT_NOREF (1 << 5) /* Error no external reference */
53 #define AD7192_STAT_PARITY (1 << 4) /* Parity */
54 #define AD7192_STAT_CH3 (1 << 2) /* Channel 3 */
55 #define AD7192_STAT_CH2 (1 << 1) /* Channel 2 */
56 #define AD7192_STAT_CH1 (1 << 0) /* Channel 1 */
57
58 /* Mode Register Bit Designations (AD7192_REG_MODE) */
59 #define AD7192_MODE_SEL(x) (((x) & 0x7) << 21) /* Operation Mode Select */
60 #define AD7192_MODE_DAT_STA (1 << 20) /* Status Register transmission */
61 #define AD7192_MODE_CLKSRC(x) (((x) & 0x3) << 18) /* Clock Source Select */
62 #define AD7192_MODE_SINC3 (1 << 15) /* SINC3 Filter Select */
63 #define AD7192_MODE_ACX (1 << 14) /* AC excitation enable(AD7195 only)*/
64 #define AD7192_MODE_ENPAR (1 << 13) /* Parity Enable */
65 #define AD7192_MODE_CLKDIV (1 << 12) /* Clock divide by 2 (AD7190/2 only)*/
66 #define AD7192_MODE_SCYCLE (1 << 11) /* Single cycle conversion */
67 #define AD7192_MODE_REJ60 (1 << 10) /* 50/60Hz notch filter */
68 #define AD7192_MODE_RATE(x) ((x) & 0x3FF) /* Filter Update Rate Select */
69
70 /* Mode Register: AD7192_MODE_SEL options */
71 #define AD7192_MODE_CONT 0 /* Continuous Conversion Mode */
72 #define AD7192_MODE_SINGLE 1 /* Single Conversion Mode */
73 #define AD7192_MODE_IDLE 2 /* Idle Mode */
74 #define AD7192_MODE_PWRDN 3 /* Power-Down Mode */
75 #define AD7192_MODE_CAL_INT_ZERO 4 /* Internal Zero-Scale Calibration */
76 #define AD7192_MODE_CAL_INT_FULL 5 /* Internal Full-Scale Calibration */
77 #define AD7192_MODE_CAL_SYS_ZERO 6 /* System Zero-Scale Calibration */
78 #define AD7192_MODE_CAL_SYS_FULL 7 /* System Full-Scale Calibration */
79
80 /* Mode Register: AD7192_MODE_CLKSRC options */
81 #define AD7192_CLK_EXT_MCLK1_2 0 /* External 4.92 MHz Clock connected
82 * from MCLK1 to MCLK2 */
83 #define AD7192_CLK_EXT_MCLK2 1 /* External Clock applied to MCLK2 */
84 #define AD7192_CLK_INT 2 /* Internal 4.92 MHz Clock not
85 * available at the MCLK2 pin */
86 #define AD7192_CLK_INT_CO 3 /* Internal 4.92 MHz Clock available
87 * at the MCLK2 pin */
88
89
90 /* Configuration Register Bit Designations (AD7192_REG_CONF) */
91
92 #define AD7192_CONF_CHOP (1 << 23) /* CHOP enable */
93 #define AD7192_CONF_REFSEL (1 << 20) /* REFIN1/REFIN2 Reference Select */
94 #define AD7192_CONF_CHAN(x) (((x) & 0xFF) << 8) /* Channel select */
95 #define AD7192_CONF_BURN (1 << 7) /* Burnout current enable */
96 #define AD7192_CONF_REFDET (1 << 6) /* Reference detect enable */
97 #define AD7192_CONF_BUF (1 << 4) /* Buffered Mode Enable */
98 #define AD7192_CONF_UNIPOLAR (1 << 3) /* Unipolar/Bipolar Enable */
99 #define AD7192_CONF_GAIN(x) ((x) & 0x7) /* Gain Select */
100
101 #define AD7192_CH_AIN1P_AIN2M 0 /* AIN1(+) - AIN2(-) */
102 #define AD7192_CH_AIN3P_AIN4M 1 /* AIN3(+) - AIN4(-) */
103 #define AD7192_CH_TEMP 2 /* Temp Sensor */
104 #define AD7192_CH_AIN2P_AIN2M 3 /* AIN2(+) - AIN2(-) */
105 #define AD7192_CH_AIN1 4 /* AIN1 - AINCOM */
106 #define AD7192_CH_AIN2 5 /* AIN2 - AINCOM */
107 #define AD7192_CH_AIN3 6 /* AIN3 - AINCOM */
108 #define AD7192_CH_AIN4 7 /* AIN4 - AINCOM */
109
110 /* ID Register Bit Designations (AD7192_REG_ID) */
111 #define ID_AD7190 0x4
112 #define ID_AD7192 0x0
113 #define ID_AD7195 0x6
114 #define AD7192_ID_MASK 0x0F
115
116 /* GPOCON Register Bit Designations (AD7192_REG_GPOCON) */
117 #define AD7192_GPOCON_BPDSW (1 << 6) /* Bridge power-down switch enable */
118 #define AD7192_GPOCON_GP32EN (1 << 5) /* Digital Output P3 and P2 enable */
119 #define AD7192_GPOCON_GP10EN (1 << 4) /* Digital Output P1 and P0 enable */
120 #define AD7192_GPOCON_P3DAT (1 << 3) /* P3 state */
121 #define AD7192_GPOCON_P2DAT (1 << 2) /* P2 state */
122 #define AD7192_GPOCON_P1DAT (1 << 1) /* P1 state */
123 #define AD7192_GPOCON_P0DAT (1 << 0) /* P0 state */
124
125 #define AD7192_INT_FREQ_MHz 4915200
126
127 /* NOTE:
128 * The AD7190/2/5 features a dual use data out ready DOUT/RDY output.
129 * In order to avoid contentions on the SPI bus, it's therefore necessary
130 * to use spi bus locking.
131 *
132 * The DOUT/RDY output must also be wired to an interrupt capable GPIO.
133 */
134
135 struct ad7192_state {
136 struct spi_device *spi;
137 struct iio_trigger *trig;
138 struct regulator *reg;
139 struct ad7192_platform_data *pdata;
140 wait_queue_head_t wq_data_avail;
141 bool done;
142 bool irq_dis;
143 u16 int_vref_mv;
144 u32 mclk;
145 u32 f_order;
146 u32 mode;
147 u32 conf;
148 u32 scale_avail[8][2];
149 long available_scan_masks[9];
150 u8 gpocon;
151 u8 devid;
152 /*
153 * DMA (thus cache coherency maintenance) requires the
154 * transfer buffers to live in their own cache lines.
155 */
156 u8 data[4] ____cacheline_aligned;
157 };
158
__ad7192_write_reg(struct ad7192_state * st,bool locked,bool cs_change,unsigned char reg,unsigned size,unsigned val)159 static int __ad7192_write_reg(struct ad7192_state *st, bool locked,
160 bool cs_change, unsigned char reg,
161 unsigned size, unsigned val)
162 {
163 u8 *data = st->data;
164 struct spi_transfer t = {
165 .tx_buf = data,
166 .len = size + 1,
167 .cs_change = cs_change,
168 };
169 struct spi_message m;
170
171 data[0] = AD7192_COMM_WRITE | AD7192_COMM_ADDR(reg);
172
173 switch (size) {
174 case 3:
175 data[1] = val >> 16;
176 data[2] = val >> 8;
177 data[3] = val;
178 break;
179 case 2:
180 data[1] = val >> 8;
181 data[2] = val;
182 break;
183 case 1:
184 data[1] = val;
185 break;
186 default:
187 return -EINVAL;
188 }
189
190 spi_message_init(&m);
191 spi_message_add_tail(&t, &m);
192
193 if (locked)
194 return spi_sync_locked(st->spi, &m);
195 else
196 return spi_sync(st->spi, &m);
197 }
198
ad7192_write_reg(struct ad7192_state * st,unsigned reg,unsigned size,unsigned val)199 static int ad7192_write_reg(struct ad7192_state *st,
200 unsigned reg, unsigned size, unsigned val)
201 {
202 return __ad7192_write_reg(st, false, false, reg, size, val);
203 }
204
__ad7192_read_reg(struct ad7192_state * st,bool locked,bool cs_change,unsigned char reg,int * val,unsigned size)205 static int __ad7192_read_reg(struct ad7192_state *st, bool locked,
206 bool cs_change, unsigned char reg,
207 int *val, unsigned size)
208 {
209 u8 *data = st->data;
210 int ret;
211 struct spi_transfer t[] = {
212 {
213 .tx_buf = data,
214 .len = 1,
215 }, {
216 .rx_buf = data,
217 .len = size,
218 .cs_change = cs_change,
219 },
220 };
221 struct spi_message m;
222
223 data[0] = AD7192_COMM_READ | AD7192_COMM_ADDR(reg);
224
225 spi_message_init(&m);
226 spi_message_add_tail(&t[0], &m);
227 spi_message_add_tail(&t[1], &m);
228
229 if (locked)
230 ret = spi_sync_locked(st->spi, &m);
231 else
232 ret = spi_sync(st->spi, &m);
233
234 if (ret < 0)
235 return ret;
236
237 switch (size) {
238 case 3:
239 *val = data[0] << 16 | data[1] << 8 | data[2];
240 break;
241 case 2:
242 *val = data[0] << 8 | data[1];
243 break;
244 case 1:
245 *val = data[0];
246 break;
247 default:
248 return -EINVAL;
249 }
250
251 return 0;
252 }
253
ad7192_read_reg(struct ad7192_state * st,unsigned reg,int * val,unsigned size)254 static int ad7192_read_reg(struct ad7192_state *st,
255 unsigned reg, int *val, unsigned size)
256 {
257 return __ad7192_read_reg(st, 0, 0, reg, val, size);
258 }
259
ad7192_read(struct ad7192_state * st,unsigned ch,unsigned len,int * val)260 static int ad7192_read(struct ad7192_state *st, unsigned ch,
261 unsigned len, int *val)
262 {
263 int ret;
264 st->conf = (st->conf & ~AD7192_CONF_CHAN(-1)) |
265 AD7192_CONF_CHAN(1 << ch);
266 st->mode = (st->mode & ~AD7192_MODE_SEL(-1)) |
267 AD7192_MODE_SEL(AD7192_MODE_SINGLE);
268
269 ad7192_write_reg(st, AD7192_REG_CONF, 3, st->conf);
270
271 spi_bus_lock(st->spi->master);
272 st->done = false;
273
274 ret = __ad7192_write_reg(st, 1, 1, AD7192_REG_MODE, 3, st->mode);
275 if (ret < 0)
276 goto out;
277
278 st->irq_dis = false;
279 enable_irq(st->spi->irq);
280 wait_event_interruptible(st->wq_data_avail, st->done);
281
282 ret = __ad7192_read_reg(st, 1, 0, AD7192_REG_DATA, val, len);
283 out:
284 spi_bus_unlock(st->spi->master);
285
286 return ret;
287 }
288
ad7192_calibrate(struct ad7192_state * st,unsigned mode,unsigned ch)289 static int ad7192_calibrate(struct ad7192_state *st, unsigned mode, unsigned ch)
290 {
291 int ret;
292
293 st->conf = (st->conf & ~AD7192_CONF_CHAN(-1)) |
294 AD7192_CONF_CHAN(1 << ch);
295 st->mode = (st->mode & ~AD7192_MODE_SEL(-1)) | AD7192_MODE_SEL(mode);
296
297 ad7192_write_reg(st, AD7192_REG_CONF, 3, st->conf);
298
299 spi_bus_lock(st->spi->master);
300 st->done = false;
301
302 ret = __ad7192_write_reg(st, 1, 1, AD7192_REG_MODE, 3,
303 (st->devid != ID_AD7195) ?
304 st->mode | AD7192_MODE_CLKDIV :
305 st->mode);
306 if (ret < 0)
307 goto out;
308
309 st->irq_dis = false;
310 enable_irq(st->spi->irq);
311 wait_event_interruptible(st->wq_data_avail, st->done);
312
313 st->mode = (st->mode & ~AD7192_MODE_SEL(-1)) |
314 AD7192_MODE_SEL(AD7192_MODE_IDLE);
315
316 ret = __ad7192_write_reg(st, 1, 0, AD7192_REG_MODE, 3, st->mode);
317 out:
318 spi_bus_unlock(st->spi->master);
319
320 return ret;
321 }
322
323 static const u8 ad7192_calib_arr[8][2] = {
324 {AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN1},
325 {AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN1},
326 {AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN2},
327 {AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN2},
328 {AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN3},
329 {AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN3},
330 {AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN4},
331 {AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN4}
332 };
333
ad7192_calibrate_all(struct ad7192_state * st)334 static int ad7192_calibrate_all(struct ad7192_state *st)
335 {
336 int i, ret;
337
338 for (i = 0; i < ARRAY_SIZE(ad7192_calib_arr); i++) {
339 ret = ad7192_calibrate(st, ad7192_calib_arr[i][0],
340 ad7192_calib_arr[i][1]);
341 if (ret)
342 goto out;
343 }
344
345 return 0;
346 out:
347 dev_err(&st->spi->dev, "Calibration failed\n");
348 return ret;
349 }
350
ad7192_setup(struct ad7192_state * st)351 static int ad7192_setup(struct ad7192_state *st)
352 {
353 struct iio_dev *indio_dev = spi_get_drvdata(st->spi);
354 struct ad7192_platform_data *pdata = st->pdata;
355 unsigned long long scale_uv;
356 int i, ret, id;
357 u8 ones[6];
358
359 /* reset the serial interface */
360 memset(&ones, 0xFF, 6);
361 ret = spi_write(st->spi, &ones, 6);
362 if (ret < 0)
363 goto out;
364 msleep(1); /* Wait for at least 500us */
365
366 /* write/read test for device presence */
367 ret = ad7192_read_reg(st, AD7192_REG_ID, &id, 1);
368 if (ret)
369 goto out;
370
371 id &= AD7192_ID_MASK;
372
373 if (id != st->devid)
374 dev_warn(&st->spi->dev, "device ID query failed (0x%X)\n", id);
375
376 switch (pdata->clock_source_sel) {
377 case AD7192_CLK_EXT_MCLK1_2:
378 case AD7192_CLK_EXT_MCLK2:
379 st->mclk = AD7192_INT_FREQ_MHz;
380 break;
381 case AD7192_CLK_INT:
382 case AD7192_CLK_INT_CO:
383 if (pdata->ext_clk_Hz)
384 st->mclk = pdata->ext_clk_Hz;
385 else
386 st->mclk = AD7192_INT_FREQ_MHz;
387 break;
388 default:
389 ret = -EINVAL;
390 goto out;
391 }
392
393 st->mode = AD7192_MODE_SEL(AD7192_MODE_IDLE) |
394 AD7192_MODE_CLKSRC(pdata->clock_source_sel) |
395 AD7192_MODE_RATE(480);
396
397 st->conf = AD7192_CONF_GAIN(0);
398
399 if (pdata->rej60_en)
400 st->mode |= AD7192_MODE_REJ60;
401
402 if (pdata->sinc3_en)
403 st->mode |= AD7192_MODE_SINC3;
404
405 if (pdata->refin2_en && (st->devid != ID_AD7195))
406 st->conf |= AD7192_CONF_REFSEL;
407
408 if (pdata->chop_en) {
409 st->conf |= AD7192_CONF_CHOP;
410 if (pdata->sinc3_en)
411 st->f_order = 3; /* SINC 3rd order */
412 else
413 st->f_order = 4; /* SINC 4th order */
414 } else {
415 st->f_order = 1;
416 }
417
418 if (pdata->buf_en)
419 st->conf |= AD7192_CONF_BUF;
420
421 if (pdata->unipolar_en)
422 st->conf |= AD7192_CONF_UNIPOLAR;
423
424 if (pdata->burnout_curr_en)
425 st->conf |= AD7192_CONF_BURN;
426
427 ret = ad7192_write_reg(st, AD7192_REG_MODE, 3, st->mode);
428 if (ret)
429 goto out;
430
431 ret = ad7192_write_reg(st, AD7192_REG_CONF, 3, st->conf);
432 if (ret)
433 goto out;
434
435 ret = ad7192_calibrate_all(st);
436 if (ret)
437 goto out;
438
439 /* Populate available ADC input ranges */
440 for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) {
441 scale_uv = ((u64)st->int_vref_mv * 100000000)
442 >> (indio_dev->channels[0].scan_type.realbits -
443 ((st->conf & AD7192_CONF_UNIPOLAR) ? 0 : 1));
444 scale_uv >>= i;
445
446 st->scale_avail[i][1] = do_div(scale_uv, 100000000) * 10;
447 st->scale_avail[i][0] = scale_uv;
448 }
449
450 return 0;
451 out:
452 dev_err(&st->spi->dev, "setup failed\n");
453 return ret;
454 }
455
ad7192_ring_preenable(struct iio_dev * indio_dev)456 static int ad7192_ring_preenable(struct iio_dev *indio_dev)
457 {
458 struct ad7192_state *st = iio_priv(indio_dev);
459 struct iio_buffer *ring = indio_dev->buffer;
460 size_t d_size;
461 unsigned channel;
462
463 if (bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength))
464 return -EINVAL;
465
466 channel = find_first_bit(indio_dev->active_scan_mask,
467 indio_dev->masklength);
468
469 d_size = bitmap_weight(indio_dev->active_scan_mask,
470 indio_dev->masklength) *
471 indio_dev->channels[0].scan_type.storagebits / 8;
472
473 if (ring->scan_timestamp) {
474 d_size += sizeof(s64);
475
476 if (d_size % sizeof(s64))
477 d_size += sizeof(s64) - (d_size % sizeof(s64));
478 }
479
480 if (indio_dev->buffer->access->set_bytes_per_datum)
481 indio_dev->buffer->access->
482 set_bytes_per_datum(indio_dev->buffer, d_size);
483
484 st->mode = (st->mode & ~AD7192_MODE_SEL(-1)) |
485 AD7192_MODE_SEL(AD7192_MODE_CONT);
486 st->conf = (st->conf & ~AD7192_CONF_CHAN(-1)) |
487 AD7192_CONF_CHAN(1 << indio_dev->channels[channel].address);
488
489 ad7192_write_reg(st, AD7192_REG_CONF, 3, st->conf);
490
491 spi_bus_lock(st->spi->master);
492 __ad7192_write_reg(st, 1, 1, AD7192_REG_MODE, 3, st->mode);
493
494 st->irq_dis = false;
495 enable_irq(st->spi->irq);
496
497 return 0;
498 }
499
ad7192_ring_postdisable(struct iio_dev * indio_dev)500 static int ad7192_ring_postdisable(struct iio_dev *indio_dev)
501 {
502 struct ad7192_state *st = iio_priv(indio_dev);
503
504 st->mode = (st->mode & ~AD7192_MODE_SEL(-1)) |
505 AD7192_MODE_SEL(AD7192_MODE_IDLE);
506
507 st->done = false;
508 wait_event_interruptible(st->wq_data_avail, st->done);
509
510 if (!st->irq_dis)
511 disable_irq_nosync(st->spi->irq);
512
513 __ad7192_write_reg(st, 1, 0, AD7192_REG_MODE, 3, st->mode);
514
515 return spi_bus_unlock(st->spi->master);
516 }
517
518 /**
519 * ad7192_trigger_handler() bh of trigger launched polling to ring buffer
520 **/
ad7192_trigger_handler(int irq,void * p)521 static irqreturn_t ad7192_trigger_handler(int irq, void *p)
522 {
523 struct iio_poll_func *pf = p;
524 struct iio_dev *indio_dev = pf->indio_dev;
525 struct iio_buffer *ring = indio_dev->buffer;
526 struct ad7192_state *st = iio_priv(indio_dev);
527 s64 dat64[2];
528 s32 *dat32 = (s32 *)dat64;
529
530 if (!bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength))
531 __ad7192_read_reg(st, 1, 1, AD7192_REG_DATA,
532 dat32,
533 indio_dev->channels[0].scan_type.realbits/8);
534
535 /* Guaranteed to be aligned with 8 byte boundary */
536 if (ring->scan_timestamp)
537 dat64[1] = pf->timestamp;
538
539 ring->access->store_to(ring, (u8 *)dat64, pf->timestamp);
540
541 iio_trigger_notify_done(indio_dev->trig);
542 st->irq_dis = false;
543 enable_irq(st->spi->irq);
544
545 return IRQ_HANDLED;
546 }
547
548 static const struct iio_buffer_setup_ops ad7192_ring_setup_ops = {
549 .preenable = &ad7192_ring_preenable,
550 .postenable = &iio_triggered_buffer_postenable,
551 .predisable = &iio_triggered_buffer_predisable,
552 .postdisable = &ad7192_ring_postdisable,
553 };
554
ad7192_register_ring_funcs_and_init(struct iio_dev * indio_dev)555 static int ad7192_register_ring_funcs_and_init(struct iio_dev *indio_dev)
556 {
557 int ret;
558
559 indio_dev->buffer = iio_sw_rb_allocate(indio_dev);
560 if (!indio_dev->buffer) {
561 ret = -ENOMEM;
562 goto error_ret;
563 }
564 /* Effectively select the ring buffer implementation */
565 indio_dev->buffer->access = &ring_sw_access_funcs;
566 indio_dev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time,
567 &ad7192_trigger_handler,
568 IRQF_ONESHOT,
569 indio_dev,
570 "ad7192_consumer%d",
571 indio_dev->id);
572 if (indio_dev->pollfunc == NULL) {
573 ret = -ENOMEM;
574 goto error_deallocate_sw_rb;
575 }
576
577 /* Ring buffer functions - here trigger setup related */
578 indio_dev->setup_ops = &ad7192_ring_setup_ops;
579
580 /* Flag that polled ring buffering is possible */
581 indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
582 return 0;
583
584 error_deallocate_sw_rb:
585 iio_sw_rb_free(indio_dev->buffer);
586 error_ret:
587 return ret;
588 }
589
ad7192_ring_cleanup(struct iio_dev * indio_dev)590 static void ad7192_ring_cleanup(struct iio_dev *indio_dev)
591 {
592 iio_dealloc_pollfunc(indio_dev->pollfunc);
593 iio_sw_rb_free(indio_dev->buffer);
594 }
595
596 /**
597 * ad7192_data_rdy_trig_poll() the event handler for the data rdy trig
598 **/
ad7192_data_rdy_trig_poll(int irq,void * private)599 static irqreturn_t ad7192_data_rdy_trig_poll(int irq, void *private)
600 {
601 struct ad7192_state *st = iio_priv(private);
602
603 st->done = true;
604 wake_up_interruptible(&st->wq_data_avail);
605 disable_irq_nosync(irq);
606 st->irq_dis = true;
607 iio_trigger_poll(st->trig, iio_get_time_ns());
608
609 return IRQ_HANDLED;
610 }
611
612 static struct iio_trigger_ops ad7192_trigger_ops = {
613 .owner = THIS_MODULE,
614 };
615
ad7192_probe_trigger(struct iio_dev * indio_dev)616 static int ad7192_probe_trigger(struct iio_dev *indio_dev)
617 {
618 struct ad7192_state *st = iio_priv(indio_dev);
619 int ret;
620
621 st->trig = iio_allocate_trigger("%s-dev%d",
622 spi_get_device_id(st->spi)->name,
623 indio_dev->id);
624 if (st->trig == NULL) {
625 ret = -ENOMEM;
626 goto error_ret;
627 }
628 st->trig->ops = &ad7192_trigger_ops;
629 ret = request_irq(st->spi->irq,
630 ad7192_data_rdy_trig_poll,
631 IRQF_TRIGGER_LOW,
632 spi_get_device_id(st->spi)->name,
633 indio_dev);
634 if (ret)
635 goto error_free_trig;
636
637 disable_irq_nosync(st->spi->irq);
638 st->irq_dis = true;
639 st->trig->dev.parent = &st->spi->dev;
640 st->trig->private_data = indio_dev;
641
642 ret = iio_trigger_register(st->trig);
643
644 /* select default trigger */
645 indio_dev->trig = st->trig;
646 if (ret)
647 goto error_free_irq;
648
649 return 0;
650
651 error_free_irq:
652 free_irq(st->spi->irq, indio_dev);
653 error_free_trig:
654 iio_free_trigger(st->trig);
655 error_ret:
656 return ret;
657 }
658
ad7192_remove_trigger(struct iio_dev * indio_dev)659 static void ad7192_remove_trigger(struct iio_dev *indio_dev)
660 {
661 struct ad7192_state *st = iio_priv(indio_dev);
662
663 iio_trigger_unregister(st->trig);
664 free_irq(st->spi->irq, indio_dev);
665 iio_free_trigger(st->trig);
666 }
667
ad7192_read_frequency(struct device * dev,struct device_attribute * attr,char * buf)668 static ssize_t ad7192_read_frequency(struct device *dev,
669 struct device_attribute *attr,
670 char *buf)
671 {
672 struct iio_dev *indio_dev = dev_get_drvdata(dev);
673 struct ad7192_state *st = iio_priv(indio_dev);
674
675 return sprintf(buf, "%d\n", st->mclk /
676 (st->f_order * 1024 * AD7192_MODE_RATE(st->mode)));
677 }
678
ad7192_write_frequency(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)679 static ssize_t ad7192_write_frequency(struct device *dev,
680 struct device_attribute *attr,
681 const char *buf,
682 size_t len)
683 {
684 struct iio_dev *indio_dev = dev_get_drvdata(dev);
685 struct ad7192_state *st = iio_priv(indio_dev);
686 unsigned long lval;
687 int div, ret;
688
689 ret = strict_strtoul(buf, 10, &lval);
690 if (ret)
691 return ret;
692
693 mutex_lock(&indio_dev->mlock);
694 if (iio_buffer_enabled(indio_dev)) {
695 mutex_unlock(&indio_dev->mlock);
696 return -EBUSY;
697 }
698
699 div = st->mclk / (lval * st->f_order * 1024);
700 if (div < 1 || div > 1023) {
701 ret = -EINVAL;
702 goto out;
703 }
704
705 st->mode &= ~AD7192_MODE_RATE(-1);
706 st->mode |= AD7192_MODE_RATE(div);
707 ad7192_write_reg(st, AD7192_REG_MODE, 3, st->mode);
708
709 out:
710 mutex_unlock(&indio_dev->mlock);
711
712 return ret ? ret : len;
713 }
714
715 static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
716 ad7192_read_frequency,
717 ad7192_write_frequency);
718
719
ad7192_show_scale_available(struct device * dev,struct device_attribute * attr,char * buf)720 static ssize_t ad7192_show_scale_available(struct device *dev,
721 struct device_attribute *attr, char *buf)
722 {
723 struct iio_dev *indio_dev = dev_get_drvdata(dev);
724 struct ad7192_state *st = iio_priv(indio_dev);
725 int i, len = 0;
726
727 for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++)
728 len += sprintf(buf + len, "%d.%09u ", st->scale_avail[i][0],
729 st->scale_avail[i][1]);
730
731 len += sprintf(buf + len, "\n");
732
733 return len;
734 }
735
736 static IIO_DEVICE_ATTR_NAMED(in_v_m_v_scale_available,
737 in_voltage-voltage_scale_available,
738 S_IRUGO, ad7192_show_scale_available, NULL, 0);
739
740 static IIO_DEVICE_ATTR(in_voltage_scale_available, S_IRUGO,
741 ad7192_show_scale_available, NULL, 0);
742
ad7192_show_ac_excitation(struct device * dev,struct device_attribute * attr,char * buf)743 static ssize_t ad7192_show_ac_excitation(struct device *dev,
744 struct device_attribute *attr,
745 char *buf)
746 {
747 struct iio_dev *indio_dev = dev_get_drvdata(dev);
748 struct ad7192_state *st = iio_priv(indio_dev);
749
750 return sprintf(buf, "%d\n", !!(st->mode & AD7192_MODE_ACX));
751 }
752
ad7192_show_bridge_switch(struct device * dev,struct device_attribute * attr,char * buf)753 static ssize_t ad7192_show_bridge_switch(struct device *dev,
754 struct device_attribute *attr,
755 char *buf)
756 {
757 struct iio_dev *indio_dev = dev_get_drvdata(dev);
758 struct ad7192_state *st = iio_priv(indio_dev);
759
760 return sprintf(buf, "%d\n", !!(st->gpocon & AD7192_GPOCON_BPDSW));
761 }
762
ad7192_set(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)763 static ssize_t ad7192_set(struct device *dev,
764 struct device_attribute *attr,
765 const char *buf,
766 size_t len)
767 {
768 struct iio_dev *indio_dev = dev_get_drvdata(dev);
769 struct ad7192_state *st = iio_priv(indio_dev);
770 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
771 int ret;
772 bool val;
773
774 ret = strtobool(buf, &val);
775 if (ret < 0)
776 return ret;
777
778 mutex_lock(&indio_dev->mlock);
779 if (iio_buffer_enabled(indio_dev)) {
780 mutex_unlock(&indio_dev->mlock);
781 return -EBUSY;
782 }
783
784 switch ((u32) this_attr->address) {
785 case AD7192_REG_GPOCON:
786 if (val)
787 st->gpocon |= AD7192_GPOCON_BPDSW;
788 else
789 st->gpocon &= ~AD7192_GPOCON_BPDSW;
790
791 ad7192_write_reg(st, AD7192_REG_GPOCON, 1, st->gpocon);
792 break;
793 case AD7192_REG_MODE:
794 if (val)
795 st->mode |= AD7192_MODE_ACX;
796 else
797 st->mode &= ~AD7192_MODE_ACX;
798
799 ad7192_write_reg(st, AD7192_REG_GPOCON, 3, st->mode);
800 break;
801 default:
802 ret = -EINVAL;
803 }
804
805 mutex_unlock(&indio_dev->mlock);
806
807 return ret ? ret : len;
808 }
809
810 static IIO_DEVICE_ATTR(bridge_switch_en, S_IRUGO | S_IWUSR,
811 ad7192_show_bridge_switch, ad7192_set,
812 AD7192_REG_GPOCON);
813
814 static IIO_DEVICE_ATTR(ac_excitation_en, S_IRUGO | S_IWUSR,
815 ad7192_show_ac_excitation, ad7192_set,
816 AD7192_REG_MODE);
817
818 static struct attribute *ad7192_attributes[] = {
819 &iio_dev_attr_sampling_frequency.dev_attr.attr,
820 &iio_dev_attr_in_v_m_v_scale_available.dev_attr.attr,
821 &iio_dev_attr_in_voltage_scale_available.dev_attr.attr,
822 &iio_dev_attr_bridge_switch_en.dev_attr.attr,
823 &iio_dev_attr_ac_excitation_en.dev_attr.attr,
824 NULL
825 };
826
ad7192_attr_is_visible(struct kobject * kobj,struct attribute * attr,int n)827 static umode_t ad7192_attr_is_visible(struct kobject *kobj,
828 struct attribute *attr, int n)
829 {
830 struct device *dev = container_of(kobj, struct device, kobj);
831 struct iio_dev *indio_dev = dev_get_drvdata(dev);
832 struct ad7192_state *st = iio_priv(indio_dev);
833
834 umode_t mode = attr->mode;
835
836 if ((st->devid != ID_AD7195) &&
837 (attr == &iio_dev_attr_ac_excitation_en.dev_attr.attr))
838 mode = 0;
839
840 return mode;
841 }
842
843 static const struct attribute_group ad7192_attribute_group = {
844 .attrs = ad7192_attributes,
845 .is_visible = ad7192_attr_is_visible,
846 };
847
ad7192_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long m)848 static int ad7192_read_raw(struct iio_dev *indio_dev,
849 struct iio_chan_spec const *chan,
850 int *val,
851 int *val2,
852 long m)
853 {
854 struct ad7192_state *st = iio_priv(indio_dev);
855 int ret, smpl = 0;
856 bool unipolar = !!(st->conf & AD7192_CONF_UNIPOLAR);
857
858 switch (m) {
859 case 0:
860 mutex_lock(&indio_dev->mlock);
861 if (iio_buffer_enabled(indio_dev))
862 ret = -EBUSY;
863 else
864 ret = ad7192_read(st, chan->address,
865 chan->scan_type.realbits / 8, &smpl);
866 mutex_unlock(&indio_dev->mlock);
867
868 if (ret < 0)
869 return ret;
870
871 *val = (smpl >> chan->scan_type.shift) &
872 ((1 << (chan->scan_type.realbits)) - 1);
873
874 switch (chan->type) {
875 case IIO_VOLTAGE:
876 if (!unipolar)
877 *val -= (1 << (chan->scan_type.realbits - 1));
878 break;
879 case IIO_TEMP:
880 *val -= 0x800000;
881 *val /= 2815; /* temp Kelvin */
882 *val -= 273; /* temp Celsius */
883 break;
884 default:
885 return -EINVAL;
886 }
887 return IIO_VAL_INT;
888
889 case IIO_CHAN_INFO_SCALE:
890 switch (chan->type) {
891 case IIO_VOLTAGE:
892 mutex_lock(&indio_dev->mlock);
893 *val = st->scale_avail[AD7192_CONF_GAIN(st->conf)][0];
894 *val2 = st->scale_avail[AD7192_CONF_GAIN(st->conf)][1];
895 mutex_unlock(&indio_dev->mlock);
896 return IIO_VAL_INT_PLUS_NANO;
897 case IIO_TEMP:
898 *val = 1000;
899 return IIO_VAL_INT;
900 default:
901 return -EINVAL;
902 }
903 }
904
905 return -EINVAL;
906 }
907
ad7192_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)908 static int ad7192_write_raw(struct iio_dev *indio_dev,
909 struct iio_chan_spec const *chan,
910 int val,
911 int val2,
912 long mask)
913 {
914 struct ad7192_state *st = iio_priv(indio_dev);
915 int ret, i;
916 unsigned int tmp;
917
918 mutex_lock(&indio_dev->mlock);
919 if (iio_buffer_enabled(indio_dev)) {
920 mutex_unlock(&indio_dev->mlock);
921 return -EBUSY;
922 }
923
924 switch (mask) {
925 case IIO_CHAN_INFO_SCALE:
926 ret = -EINVAL;
927 for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++)
928 if (val2 == st->scale_avail[i][1]) {
929 tmp = st->conf;
930 st->conf &= ~AD7192_CONF_GAIN(-1);
931 st->conf |= AD7192_CONF_GAIN(i);
932
933 if (tmp != st->conf) {
934 ad7192_write_reg(st, AD7192_REG_CONF,
935 3, st->conf);
936 ad7192_calibrate_all(st);
937 }
938 ret = 0;
939 }
940
941 default:
942 ret = -EINVAL;
943 }
944
945 mutex_unlock(&indio_dev->mlock);
946
947 return ret;
948 }
949
ad7192_validate_trigger(struct iio_dev * indio_dev,struct iio_trigger * trig)950 static int ad7192_validate_trigger(struct iio_dev *indio_dev,
951 struct iio_trigger *trig)
952 {
953 if (indio_dev->trig != trig)
954 return -EINVAL;
955
956 return 0;
957 }
958
ad7192_write_raw_get_fmt(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,long mask)959 static int ad7192_write_raw_get_fmt(struct iio_dev *indio_dev,
960 struct iio_chan_spec const *chan,
961 long mask)
962 {
963 return IIO_VAL_INT_PLUS_NANO;
964 }
965
966 static const struct iio_info ad7192_info = {
967 .read_raw = &ad7192_read_raw,
968 .write_raw = &ad7192_write_raw,
969 .write_raw_get_fmt = &ad7192_write_raw_get_fmt,
970 .attrs = &ad7192_attribute_group,
971 .validate_trigger = ad7192_validate_trigger,
972 .driver_module = THIS_MODULE,
973 };
974
975 #define AD7192_CHAN_DIFF(_chan, _chan2, _name, _address, _si) \
976 { .type = IIO_VOLTAGE, \
977 .differential = 1, \
978 .indexed = 1, \
979 .extend_name = _name, \
980 .channel = _chan, \
981 .channel2 = _chan2, \
982 .info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT, \
983 .address = _address, \
984 .scan_index = _si, \
985 .scan_type = IIO_ST('s', 24, 32, 0)}
986
987 #define AD7192_CHAN(_chan, _address, _si) \
988 { .type = IIO_VOLTAGE, \
989 .indexed = 1, \
990 .channel = _chan, \
991 .info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT, \
992 .address = _address, \
993 .scan_index = _si, \
994 .scan_type = IIO_ST('s', 24, 32, 0)}
995
996 #define AD7192_CHAN_TEMP(_chan, _address, _si) \
997 { .type = IIO_TEMP, \
998 .indexed = 1, \
999 .channel = _chan, \
1000 .info_mask = IIO_CHAN_INFO_SCALE_SEPARATE_BIT, \
1001 .address = _address, \
1002 .scan_index = _si, \
1003 .scan_type = IIO_ST('s', 24, 32, 0)}
1004
1005 static struct iio_chan_spec ad7192_channels[] = {
1006 AD7192_CHAN_DIFF(1, 2, NULL, AD7192_CH_AIN1P_AIN2M, 0),
1007 AD7192_CHAN_DIFF(3, 4, NULL, AD7192_CH_AIN3P_AIN4M, 1),
1008 AD7192_CHAN_TEMP(0, AD7192_CH_TEMP, 2),
1009 AD7192_CHAN_DIFF(2, 2, "shorted", AD7192_CH_AIN2P_AIN2M, 3),
1010 AD7192_CHAN(1, AD7192_CH_AIN1, 4),
1011 AD7192_CHAN(2, AD7192_CH_AIN2, 5),
1012 AD7192_CHAN(3, AD7192_CH_AIN3, 6),
1013 AD7192_CHAN(4, AD7192_CH_AIN4, 7),
1014 IIO_CHAN_SOFT_TIMESTAMP(8),
1015 };
1016
ad7192_probe(struct spi_device * spi)1017 static int __devinit ad7192_probe(struct spi_device *spi)
1018 {
1019 struct ad7192_platform_data *pdata = spi->dev.platform_data;
1020 struct ad7192_state *st;
1021 struct iio_dev *indio_dev;
1022 int ret, i , voltage_uv = 0;
1023
1024 if (!pdata) {
1025 dev_err(&spi->dev, "no platform data?\n");
1026 return -ENODEV;
1027 }
1028
1029 if (!spi->irq) {
1030 dev_err(&spi->dev, "no IRQ?\n");
1031 return -ENODEV;
1032 }
1033
1034 indio_dev = iio_allocate_device(sizeof(*st));
1035 if (indio_dev == NULL)
1036 return -ENOMEM;
1037
1038 st = iio_priv(indio_dev);
1039
1040 st->reg = regulator_get(&spi->dev, "vcc");
1041 if (!IS_ERR(st->reg)) {
1042 ret = regulator_enable(st->reg);
1043 if (ret)
1044 goto error_put_reg;
1045
1046 voltage_uv = regulator_get_voltage(st->reg);
1047 }
1048
1049 st->pdata = pdata;
1050
1051 if (pdata && pdata->vref_mv)
1052 st->int_vref_mv = pdata->vref_mv;
1053 else if (voltage_uv)
1054 st->int_vref_mv = voltage_uv / 1000;
1055 else
1056 dev_warn(&spi->dev, "reference voltage undefined\n");
1057
1058 spi_set_drvdata(spi, indio_dev);
1059 st->spi = spi;
1060 st->devid = spi_get_device_id(spi)->driver_data;
1061 indio_dev->dev.parent = &spi->dev;
1062 indio_dev->name = spi_get_device_id(spi)->name;
1063 indio_dev->modes = INDIO_DIRECT_MODE;
1064 indio_dev->channels = ad7192_channels;
1065 indio_dev->num_channels = ARRAY_SIZE(ad7192_channels);
1066 indio_dev->available_scan_masks = st->available_scan_masks;
1067 indio_dev->info = &ad7192_info;
1068
1069 for (i = 0; i < indio_dev->num_channels; i++)
1070 st->available_scan_masks[i] = (1 << i) | (1 <<
1071 indio_dev->channels[indio_dev->num_channels - 1].
1072 scan_index);
1073
1074 init_waitqueue_head(&st->wq_data_avail);
1075
1076 ret = ad7192_register_ring_funcs_and_init(indio_dev);
1077 if (ret)
1078 goto error_disable_reg;
1079
1080 ret = ad7192_probe_trigger(indio_dev);
1081 if (ret)
1082 goto error_ring_cleanup;
1083
1084 ret = iio_buffer_register(indio_dev,
1085 indio_dev->channels,
1086 indio_dev->num_channels);
1087 if (ret)
1088 goto error_remove_trigger;
1089
1090 ret = ad7192_setup(st);
1091 if (ret)
1092 goto error_unreg_ring;
1093
1094 ret = iio_device_register(indio_dev);
1095 if (ret < 0)
1096 goto error_unreg_ring;
1097 return 0;
1098
1099 error_unreg_ring:
1100 iio_buffer_unregister(indio_dev);
1101 error_remove_trigger:
1102 ad7192_remove_trigger(indio_dev);
1103 error_ring_cleanup:
1104 ad7192_ring_cleanup(indio_dev);
1105 error_disable_reg:
1106 if (!IS_ERR(st->reg))
1107 regulator_disable(st->reg);
1108 error_put_reg:
1109 if (!IS_ERR(st->reg))
1110 regulator_put(st->reg);
1111
1112 iio_free_device(indio_dev);
1113
1114 return ret;
1115 }
1116
ad7192_remove(struct spi_device * spi)1117 static int ad7192_remove(struct spi_device *spi)
1118 {
1119 struct iio_dev *indio_dev = spi_get_drvdata(spi);
1120 struct ad7192_state *st = iio_priv(indio_dev);
1121
1122 iio_device_unregister(indio_dev);
1123 iio_buffer_unregister(indio_dev);
1124 ad7192_remove_trigger(indio_dev);
1125 ad7192_ring_cleanup(indio_dev);
1126
1127 if (!IS_ERR(st->reg)) {
1128 regulator_disable(st->reg);
1129 regulator_put(st->reg);
1130 }
1131
1132 return 0;
1133 }
1134
1135 static const struct spi_device_id ad7192_id[] = {
1136 {"ad7190", ID_AD7190},
1137 {"ad7192", ID_AD7192},
1138 {"ad7195", ID_AD7195},
1139 {}
1140 };
1141 MODULE_DEVICE_TABLE(spi, ad7192_id);
1142
1143 static struct spi_driver ad7192_driver = {
1144 .driver = {
1145 .name = "ad7192",
1146 .owner = THIS_MODULE,
1147 },
1148 .probe = ad7192_probe,
1149 .remove = __devexit_p(ad7192_remove),
1150 .id_table = ad7192_id,
1151 };
1152 module_spi_driver(ad7192_driver);
1153
1154 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
1155 MODULE_DESCRIPTION("Analog Devices AD7190, AD7192, AD7195 ADC");
1156 MODULE_LICENSE("GPL v2");
1157