1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * AD5933 AD5934 Impedance Converter, Network Analyzer
4 *
5 * Copyright 2011 Analog Devices Inc.
6 */
7
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/device.h>
11 #include <linux/err.h>
12 #include <linux/i2c.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/regulator/consumer.h>
17 #include <linux/sysfs.h>
18 #include <linux/types.h>
19
20 #include <linux/iio/buffer.h>
21 #include <linux/iio/iio.h>
22 #include <linux/iio/kfifo_buf.h>
23 #include <linux/iio/sysfs.h>
24
25 /* AD5933/AD5934 Registers */
26 #define AD5933_REG_CONTROL_HB 0x80 /* R/W, 1 byte */
27 #define AD5933_REG_CONTROL_LB 0x81 /* R/W, 1 byte */
28 #define AD5933_REG_FREQ_START 0x82 /* R/W, 3 bytes */
29 #define AD5933_REG_FREQ_INC 0x85 /* R/W, 3 bytes */
30 #define AD5933_REG_INC_NUM 0x88 /* R/W, 2 bytes, 9 bit */
31 #define AD5933_REG_SETTLING_CYCLES 0x8A /* R/W, 2 bytes */
32 #define AD5933_REG_STATUS 0x8F /* R, 1 byte */
33 #define AD5933_REG_TEMP_DATA 0x92 /* R, 2 bytes*/
34 #define AD5933_REG_REAL_DATA 0x94 /* R, 2 bytes*/
35 #define AD5933_REG_IMAG_DATA 0x96 /* R, 2 bytes*/
36
37 /* AD5933_REG_CONTROL_HB Bits */
38 #define AD5933_CTRL_INIT_START_FREQ (0x1 << 4)
39 #define AD5933_CTRL_START_SWEEP (0x2 << 4)
40 #define AD5933_CTRL_INC_FREQ (0x3 << 4)
41 #define AD5933_CTRL_REPEAT_FREQ (0x4 << 4)
42 #define AD5933_CTRL_MEASURE_TEMP (0x9 << 4)
43 #define AD5933_CTRL_POWER_DOWN (0xA << 4)
44 #define AD5933_CTRL_STANDBY (0xB << 4)
45
46 #define AD5933_CTRL_RANGE_2000mVpp (0x0 << 1)
47 #define AD5933_CTRL_RANGE_200mVpp (0x1 << 1)
48 #define AD5933_CTRL_RANGE_400mVpp (0x2 << 1)
49 #define AD5933_CTRL_RANGE_1000mVpp (0x3 << 1)
50 #define AD5933_CTRL_RANGE(x) ((x) << 1)
51
52 #define AD5933_CTRL_PGA_GAIN_1 (0x1 << 0)
53 #define AD5933_CTRL_PGA_GAIN_5 (0x0 << 0)
54
55 /* AD5933_REG_CONTROL_LB Bits */
56 #define AD5933_CTRL_RESET (0x1 << 4)
57 #define AD5933_CTRL_INT_SYSCLK (0x0 << 3)
58 #define AD5933_CTRL_EXT_SYSCLK (0x1 << 3)
59
60 /* AD5933_REG_STATUS Bits */
61 #define AD5933_STAT_TEMP_VALID (0x1 << 0)
62 #define AD5933_STAT_DATA_VALID (0x1 << 1)
63 #define AD5933_STAT_SWEEP_DONE (0x1 << 2)
64
65 /* I2C Block Commands */
66 #define AD5933_I2C_BLOCK_WRITE 0xA0
67 #define AD5933_I2C_BLOCK_READ 0xA1
68 #define AD5933_I2C_ADDR_POINTER 0xB0
69
70 /* Device Specs */
71 #define AD5933_INT_OSC_FREQ_Hz 16776000
72 #define AD5933_MAX_OUTPUT_FREQ_Hz 100000
73 #define AD5933_MAX_RETRIES 100
74
75 #define AD5933_OUT_RANGE 1
76 #define AD5933_OUT_RANGE_AVAIL 2
77 #define AD5933_OUT_SETTLING_CYCLES 3
78 #define AD5933_IN_PGA_GAIN 4
79 #define AD5933_IN_PGA_GAIN_AVAIL 5
80 #define AD5933_FREQ_POINTS 6
81
82 #define AD5933_POLL_TIME_ms 10
83 #define AD5933_INIT_EXCITATION_TIME_ms 100
84
85 struct ad5933_state {
86 struct i2c_client *client;
87 struct regulator *reg;
88 struct clk *mclk;
89 struct delayed_work work;
90 struct mutex lock; /* Protect sensor state */
91 unsigned long mclk_hz;
92 unsigned char ctrl_hb;
93 unsigned char ctrl_lb;
94 unsigned int range_avail[4];
95 unsigned short vref_mv;
96 unsigned short settling_cycles;
97 unsigned short freq_points;
98 unsigned int freq_start;
99 unsigned int freq_inc;
100 unsigned int state;
101 unsigned int poll_time_jiffies;
102 };
103
104 #define AD5933_CHANNEL(_type, _extend_name, _info_mask_separate, _address, \
105 _scan_index, _realbits) { \
106 .type = (_type), \
107 .extend_name = (_extend_name), \
108 .info_mask_separate = (_info_mask_separate), \
109 .address = (_address), \
110 .scan_index = (_scan_index), \
111 .scan_type = { \
112 .sign = 's', \
113 .realbits = (_realbits), \
114 .storagebits = 16, \
115 }, \
116 }
117
118 static const struct iio_chan_spec ad5933_channels[] = {
119 AD5933_CHANNEL(IIO_TEMP, NULL, BIT(IIO_CHAN_INFO_RAW) |
120 BIT(IIO_CHAN_INFO_SCALE), AD5933_REG_TEMP_DATA, -1, 14),
121 /* Ring Channels */
122 AD5933_CHANNEL(IIO_VOLTAGE, "real", 0, AD5933_REG_REAL_DATA, 0, 16),
123 AD5933_CHANNEL(IIO_VOLTAGE, "imag", 0, AD5933_REG_IMAG_DATA, 1, 16),
124 };
125
ad5933_i2c_write(struct i2c_client * client,u8 reg,u8 len,u8 * data)126 static int ad5933_i2c_write(struct i2c_client *client, u8 reg, u8 len, u8 *data)
127 {
128 int ret;
129
130 while (len--) {
131 ret = i2c_smbus_write_byte_data(client, reg++, *data++);
132 if (ret < 0) {
133 dev_err(&client->dev, "I2C write error\n");
134 return ret;
135 }
136 }
137 return 0;
138 }
139
ad5933_i2c_read(struct i2c_client * client,u8 reg,u8 len,u8 * data)140 static int ad5933_i2c_read(struct i2c_client *client, u8 reg, u8 len, u8 *data)
141 {
142 int ret;
143
144 while (len--) {
145 ret = i2c_smbus_read_byte_data(client, reg++);
146 if (ret < 0) {
147 dev_err(&client->dev, "I2C read error\n");
148 return ret;
149 }
150 *data++ = ret;
151 }
152 return 0;
153 }
154
ad5933_cmd(struct ad5933_state * st,unsigned char cmd)155 static int ad5933_cmd(struct ad5933_state *st, unsigned char cmd)
156 {
157 unsigned char dat = st->ctrl_hb | cmd;
158
159 return ad5933_i2c_write(st->client,
160 AD5933_REG_CONTROL_HB, 1, &dat);
161 }
162
ad5933_reset(struct ad5933_state * st)163 static int ad5933_reset(struct ad5933_state *st)
164 {
165 unsigned char dat = st->ctrl_lb | AD5933_CTRL_RESET;
166
167 return ad5933_i2c_write(st->client,
168 AD5933_REG_CONTROL_LB, 1, &dat);
169 }
170
ad5933_wait_busy(struct ad5933_state * st,unsigned char event)171 static int ad5933_wait_busy(struct ad5933_state *st, unsigned char event)
172 {
173 unsigned char val, timeout = AD5933_MAX_RETRIES;
174 int ret;
175
176 while (timeout--) {
177 ret = ad5933_i2c_read(st->client, AD5933_REG_STATUS, 1, &val);
178 if (ret < 0)
179 return ret;
180 if (val & event)
181 return val;
182 cpu_relax();
183 mdelay(1);
184 }
185
186 return -EAGAIN;
187 }
188
ad5933_set_freq(struct ad5933_state * st,unsigned int reg,unsigned long freq)189 static int ad5933_set_freq(struct ad5933_state *st,
190 unsigned int reg, unsigned long freq)
191 {
192 unsigned long long freqreg;
193 union {
194 __be32 d32;
195 u8 d8[4];
196 } dat;
197
198 freqreg = (u64)freq * (u64)(1 << 27);
199 do_div(freqreg, st->mclk_hz / 4);
200
201 switch (reg) {
202 case AD5933_REG_FREQ_START:
203 st->freq_start = freq;
204 break;
205 case AD5933_REG_FREQ_INC:
206 st->freq_inc = freq;
207 break;
208 default:
209 return -EINVAL;
210 }
211
212 dat.d32 = cpu_to_be32(freqreg);
213 return ad5933_i2c_write(st->client, reg, 3, &dat.d8[1]);
214 }
215
ad5933_setup(struct ad5933_state * st)216 static int ad5933_setup(struct ad5933_state *st)
217 {
218 __be16 dat;
219 int ret;
220
221 ret = ad5933_reset(st);
222 if (ret < 0)
223 return ret;
224
225 ret = ad5933_set_freq(st, AD5933_REG_FREQ_START, 10000);
226 if (ret < 0)
227 return ret;
228
229 ret = ad5933_set_freq(st, AD5933_REG_FREQ_INC, 200);
230 if (ret < 0)
231 return ret;
232
233 st->settling_cycles = 10;
234 dat = cpu_to_be16(st->settling_cycles);
235
236 ret = ad5933_i2c_write(st->client,
237 AD5933_REG_SETTLING_CYCLES,
238 2, (u8 *)&dat);
239 if (ret < 0)
240 return ret;
241
242 st->freq_points = 100;
243 dat = cpu_to_be16(st->freq_points);
244
245 return ad5933_i2c_write(st->client, AD5933_REG_INC_NUM, 2, (u8 *)&dat);
246 }
247
ad5933_calc_out_ranges(struct ad5933_state * st)248 static void ad5933_calc_out_ranges(struct ad5933_state *st)
249 {
250 int i;
251 unsigned int normalized_3v3[4] = {1980, 198, 383, 970};
252
253 for (i = 0; i < 4; i++)
254 st->range_avail[i] = normalized_3v3[i] * st->vref_mv / 3300;
255 }
256
257 /*
258 * handles: AD5933_REG_FREQ_START and AD5933_REG_FREQ_INC
259 */
260
ad5933_show_frequency(struct device * dev,struct device_attribute * attr,char * buf)261 static ssize_t ad5933_show_frequency(struct device *dev,
262 struct device_attribute *attr,
263 char *buf)
264 {
265 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
266 struct ad5933_state *st = iio_priv(indio_dev);
267 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
268 int ret;
269 unsigned long long freqreg;
270 union {
271 __be32 d32;
272 u8 d8[4];
273 } dat;
274
275 ret = iio_device_claim_direct_mode(indio_dev);
276 if (ret)
277 return ret;
278 ret = ad5933_i2c_read(st->client, this_attr->address, 3, &dat.d8[1]);
279 iio_device_release_direct_mode(indio_dev);
280 if (ret < 0)
281 return ret;
282
283 freqreg = be32_to_cpu(dat.d32) & 0xFFFFFF;
284
285 freqreg = (u64)freqreg * (u64)(st->mclk_hz / 4);
286 do_div(freqreg, BIT(27));
287
288 return sprintf(buf, "%d\n", (int)freqreg);
289 }
290
ad5933_store_frequency(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)291 static ssize_t ad5933_store_frequency(struct device *dev,
292 struct device_attribute *attr,
293 const char *buf,
294 size_t len)
295 {
296 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
297 struct ad5933_state *st = iio_priv(indio_dev);
298 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
299 unsigned long val;
300 int ret;
301
302 ret = kstrtoul(buf, 10, &val);
303 if (ret)
304 return ret;
305
306 if (val > AD5933_MAX_OUTPUT_FREQ_Hz)
307 return -EINVAL;
308
309 ret = iio_device_claim_direct_mode(indio_dev);
310 if (ret)
311 return ret;
312 ret = ad5933_set_freq(st, this_attr->address, val);
313 iio_device_release_direct_mode(indio_dev);
314
315 return ret ? ret : len;
316 }
317
318 static IIO_DEVICE_ATTR(out_altvoltage0_frequency_start, 0644,
319 ad5933_show_frequency,
320 ad5933_store_frequency,
321 AD5933_REG_FREQ_START);
322
323 static IIO_DEVICE_ATTR(out_altvoltage0_frequency_increment, 0644,
324 ad5933_show_frequency,
325 ad5933_store_frequency,
326 AD5933_REG_FREQ_INC);
327
ad5933_show(struct device * dev,struct device_attribute * attr,char * buf)328 static ssize_t ad5933_show(struct device *dev,
329 struct device_attribute *attr,
330 char *buf)
331 {
332 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
333 struct ad5933_state *st = iio_priv(indio_dev);
334 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
335 int ret = 0, len = 0;
336
337 mutex_lock(&st->lock);
338 switch ((u32)this_attr->address) {
339 case AD5933_OUT_RANGE:
340 len = sprintf(buf, "%u\n",
341 st->range_avail[(st->ctrl_hb >> 1) & 0x3]);
342 break;
343 case AD5933_OUT_RANGE_AVAIL:
344 len = sprintf(buf, "%u %u %u %u\n", st->range_avail[0],
345 st->range_avail[3], st->range_avail[2],
346 st->range_avail[1]);
347 break;
348 case AD5933_OUT_SETTLING_CYCLES:
349 len = sprintf(buf, "%d\n", st->settling_cycles);
350 break;
351 case AD5933_IN_PGA_GAIN:
352 len = sprintf(buf, "%s\n",
353 (st->ctrl_hb & AD5933_CTRL_PGA_GAIN_1) ?
354 "1" : "0.2");
355 break;
356 case AD5933_IN_PGA_GAIN_AVAIL:
357 len = sprintf(buf, "1 0.2\n");
358 break;
359 case AD5933_FREQ_POINTS:
360 len = sprintf(buf, "%d\n", st->freq_points);
361 break;
362 default:
363 ret = -EINVAL;
364 }
365
366 mutex_unlock(&st->lock);
367 return ret ? ret : len;
368 }
369
ad5933_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)370 static ssize_t ad5933_store(struct device *dev,
371 struct device_attribute *attr,
372 const char *buf,
373 size_t len)
374 {
375 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
376 struct ad5933_state *st = iio_priv(indio_dev);
377 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
378 u16 val;
379 int i, ret = 0;
380 __be16 dat;
381
382 if (this_attr->address != AD5933_IN_PGA_GAIN) {
383 ret = kstrtou16(buf, 10, &val);
384 if (ret)
385 return ret;
386 }
387
388 ret = iio_device_claim_direct_mode(indio_dev);
389 if (ret)
390 return ret;
391 mutex_lock(&st->lock);
392 switch ((u32)this_attr->address) {
393 case AD5933_OUT_RANGE:
394 ret = -EINVAL;
395 for (i = 0; i < 4; i++)
396 if (val == st->range_avail[i]) {
397 st->ctrl_hb &= ~AD5933_CTRL_RANGE(0x3);
398 st->ctrl_hb |= AD5933_CTRL_RANGE(i);
399 ret = ad5933_cmd(st, 0);
400 break;
401 }
402 break;
403 case AD5933_IN_PGA_GAIN:
404 if (sysfs_streq(buf, "1")) {
405 st->ctrl_hb |= AD5933_CTRL_PGA_GAIN_1;
406 } else if (sysfs_streq(buf, "0.2")) {
407 st->ctrl_hb &= ~AD5933_CTRL_PGA_GAIN_1;
408 } else {
409 ret = -EINVAL;
410 break;
411 }
412 ret = ad5933_cmd(st, 0);
413 break;
414 case AD5933_OUT_SETTLING_CYCLES:
415 val = clamp(val, (u16)0, (u16)0x7FF);
416 st->settling_cycles = val;
417
418 /* 2x, 4x handling, see datasheet */
419 if (val > 1022)
420 val = (val >> 2) | (3 << 9);
421 else if (val > 511)
422 val = (val >> 1) | BIT(9);
423
424 dat = cpu_to_be16(val);
425 ret = ad5933_i2c_write(st->client,
426 AD5933_REG_SETTLING_CYCLES,
427 2, (u8 *)&dat);
428 break;
429 case AD5933_FREQ_POINTS:
430 val = clamp(val, (u16)0, (u16)511);
431 st->freq_points = val;
432
433 dat = cpu_to_be16(val);
434 ret = ad5933_i2c_write(st->client, AD5933_REG_INC_NUM, 2,
435 (u8 *)&dat);
436 break;
437 default:
438 ret = -EINVAL;
439 }
440
441 mutex_unlock(&st->lock);
442 iio_device_release_direct_mode(indio_dev);
443 return ret ? ret : len;
444 }
445
446 static IIO_DEVICE_ATTR(out_altvoltage0_raw, 0644,
447 ad5933_show,
448 ad5933_store,
449 AD5933_OUT_RANGE);
450
451 static IIO_DEVICE_ATTR(out_altvoltage0_scale_available, 0444,
452 ad5933_show,
453 NULL,
454 AD5933_OUT_RANGE_AVAIL);
455
456 static IIO_DEVICE_ATTR(in_voltage0_scale, 0644,
457 ad5933_show,
458 ad5933_store,
459 AD5933_IN_PGA_GAIN);
460
461 static IIO_DEVICE_ATTR(in_voltage0_scale_available, 0444,
462 ad5933_show,
463 NULL,
464 AD5933_IN_PGA_GAIN_AVAIL);
465
466 static IIO_DEVICE_ATTR(out_altvoltage0_frequency_points, 0644,
467 ad5933_show,
468 ad5933_store,
469 AD5933_FREQ_POINTS);
470
471 static IIO_DEVICE_ATTR(out_altvoltage0_settling_cycles, 0644,
472 ad5933_show,
473 ad5933_store,
474 AD5933_OUT_SETTLING_CYCLES);
475
476 /*
477 * note:
478 * ideally we would handle the scale attributes via the iio_info
479 * (read|write)_raw methods, however this part is a untypical since we
480 * don't create dedicated sysfs channel attributes for out0 and in0.
481 */
482 static struct attribute *ad5933_attributes[] = {
483 &iio_dev_attr_out_altvoltage0_raw.dev_attr.attr,
484 &iio_dev_attr_out_altvoltage0_scale_available.dev_attr.attr,
485 &iio_dev_attr_out_altvoltage0_frequency_start.dev_attr.attr,
486 &iio_dev_attr_out_altvoltage0_frequency_increment.dev_attr.attr,
487 &iio_dev_attr_out_altvoltage0_frequency_points.dev_attr.attr,
488 &iio_dev_attr_out_altvoltage0_settling_cycles.dev_attr.attr,
489 &iio_dev_attr_in_voltage0_scale.dev_attr.attr,
490 &iio_dev_attr_in_voltage0_scale_available.dev_attr.attr,
491 NULL
492 };
493
494 static const struct attribute_group ad5933_attribute_group = {
495 .attrs = ad5933_attributes,
496 };
497
ad5933_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long m)498 static int ad5933_read_raw(struct iio_dev *indio_dev,
499 struct iio_chan_spec const *chan,
500 int *val,
501 int *val2,
502 long m)
503 {
504 struct ad5933_state *st = iio_priv(indio_dev);
505 __be16 dat;
506 int ret;
507
508 switch (m) {
509 case IIO_CHAN_INFO_RAW:
510 ret = iio_device_claim_direct_mode(indio_dev);
511 if (ret)
512 return ret;
513 ret = ad5933_cmd(st, AD5933_CTRL_MEASURE_TEMP);
514 if (ret < 0)
515 goto out;
516 ret = ad5933_wait_busy(st, AD5933_STAT_TEMP_VALID);
517 if (ret < 0)
518 goto out;
519
520 ret = ad5933_i2c_read(st->client,
521 AD5933_REG_TEMP_DATA,
522 2, (u8 *)&dat);
523 if (ret < 0)
524 goto out;
525 iio_device_release_direct_mode(indio_dev);
526 *val = sign_extend32(be16_to_cpu(dat), 13);
527
528 return IIO_VAL_INT;
529 case IIO_CHAN_INFO_SCALE:
530 *val = 1000;
531 *val2 = 5;
532 return IIO_VAL_FRACTIONAL_LOG2;
533 }
534
535 return -EINVAL;
536 out:
537 iio_device_release_direct_mode(indio_dev);
538 return ret;
539 }
540
541 static const struct iio_info ad5933_info = {
542 .read_raw = ad5933_read_raw,
543 .attrs = &ad5933_attribute_group,
544 };
545
ad5933_ring_preenable(struct iio_dev * indio_dev)546 static int ad5933_ring_preenable(struct iio_dev *indio_dev)
547 {
548 struct ad5933_state *st = iio_priv(indio_dev);
549 int ret;
550
551 if (bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength))
552 return -EINVAL;
553
554 ret = ad5933_reset(st);
555 if (ret < 0)
556 return ret;
557
558 ret = ad5933_cmd(st, AD5933_CTRL_STANDBY);
559 if (ret < 0)
560 return ret;
561
562 ret = ad5933_cmd(st, AD5933_CTRL_INIT_START_FREQ);
563 if (ret < 0)
564 return ret;
565
566 st->state = AD5933_CTRL_INIT_START_FREQ;
567
568 return 0;
569 }
570
ad5933_ring_postenable(struct iio_dev * indio_dev)571 static int ad5933_ring_postenable(struct iio_dev *indio_dev)
572 {
573 struct ad5933_state *st = iio_priv(indio_dev);
574
575 /*
576 * AD5933_CTRL_INIT_START_FREQ:
577 * High Q complex circuits require a long time to reach steady state.
578 * To facilitate the measurement of such impedances, this mode allows
579 * the user full control of the settling time requirement before
580 * entering start frequency sweep mode where the impedance measurement
581 * takes place. In this mode the impedance is excited with the
582 * programmed start frequency (ad5933_ring_preenable),
583 * but no measurement takes place.
584 */
585
586 schedule_delayed_work(&st->work,
587 msecs_to_jiffies(AD5933_INIT_EXCITATION_TIME_ms));
588 return 0;
589 }
590
ad5933_ring_postdisable(struct iio_dev * indio_dev)591 static int ad5933_ring_postdisable(struct iio_dev *indio_dev)
592 {
593 struct ad5933_state *st = iio_priv(indio_dev);
594
595 cancel_delayed_work_sync(&st->work);
596 return ad5933_cmd(st, AD5933_CTRL_POWER_DOWN);
597 }
598
599 static const struct iio_buffer_setup_ops ad5933_ring_setup_ops = {
600 .preenable = ad5933_ring_preenable,
601 .postenable = ad5933_ring_postenable,
602 .postdisable = ad5933_ring_postdisable,
603 };
604
ad5933_register_ring_funcs_and_init(struct iio_dev * indio_dev)605 static int ad5933_register_ring_funcs_and_init(struct iio_dev *indio_dev)
606 {
607 struct iio_buffer *buffer;
608
609 buffer = iio_kfifo_allocate();
610 if (!buffer)
611 return -ENOMEM;
612
613 iio_device_attach_buffer(indio_dev, buffer);
614
615 /* Ring buffer functions - here trigger setup related */
616 indio_dev->setup_ops = &ad5933_ring_setup_ops;
617
618 return 0;
619 }
620
ad5933_work(struct work_struct * work)621 static void ad5933_work(struct work_struct *work)
622 {
623 struct ad5933_state *st = container_of(work,
624 struct ad5933_state, work.work);
625 struct iio_dev *indio_dev = i2c_get_clientdata(st->client);
626 __be16 buf[2];
627 int val[2];
628 unsigned char status;
629 int ret;
630
631 if (st->state == AD5933_CTRL_INIT_START_FREQ) {
632 /* start sweep */
633 ad5933_cmd(st, AD5933_CTRL_START_SWEEP);
634 st->state = AD5933_CTRL_START_SWEEP;
635 schedule_delayed_work(&st->work, st->poll_time_jiffies);
636 return;
637 }
638
639 ret = ad5933_i2c_read(st->client, AD5933_REG_STATUS, 1, &status);
640 if (ret)
641 return;
642
643 if (status & AD5933_STAT_DATA_VALID) {
644 int scan_count = bitmap_weight(indio_dev->active_scan_mask,
645 indio_dev->masklength);
646 ret = ad5933_i2c_read(st->client,
647 test_bit(1, indio_dev->active_scan_mask) ?
648 AD5933_REG_REAL_DATA : AD5933_REG_IMAG_DATA,
649 scan_count * 2, (u8 *)buf);
650 if (ret)
651 return;
652
653 if (scan_count == 2) {
654 val[0] = be16_to_cpu(buf[0]);
655 val[1] = be16_to_cpu(buf[1]);
656 } else {
657 val[0] = be16_to_cpu(buf[0]);
658 }
659 iio_push_to_buffers(indio_dev, val);
660 } else {
661 /* no data available - try again later */
662 schedule_delayed_work(&st->work, st->poll_time_jiffies);
663 return;
664 }
665
666 if (status & AD5933_STAT_SWEEP_DONE) {
667 /*
668 * last sample received - power down do
669 * nothing until the ring enable is toggled
670 */
671 ad5933_cmd(st, AD5933_CTRL_POWER_DOWN);
672 } else {
673 /* we just received a valid datum, move on to the next */
674 ad5933_cmd(st, AD5933_CTRL_INC_FREQ);
675 schedule_delayed_work(&st->work, st->poll_time_jiffies);
676 }
677 }
678
ad5933_probe(struct i2c_client * client,const struct i2c_device_id * id)679 static int ad5933_probe(struct i2c_client *client,
680 const struct i2c_device_id *id)
681 {
682 int ret;
683 struct ad5933_state *st;
684 struct iio_dev *indio_dev;
685 unsigned long ext_clk_hz = 0;
686
687 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
688 if (!indio_dev)
689 return -ENOMEM;
690
691 st = iio_priv(indio_dev);
692 i2c_set_clientdata(client, indio_dev);
693 st->client = client;
694
695 mutex_init(&st->lock);
696
697 st->reg = devm_regulator_get(&client->dev, "vdd");
698 if (IS_ERR(st->reg))
699 return PTR_ERR(st->reg);
700
701 ret = regulator_enable(st->reg);
702 if (ret) {
703 dev_err(&client->dev, "Failed to enable specified VDD supply\n");
704 return ret;
705 }
706 ret = regulator_get_voltage(st->reg);
707
708 if (ret < 0)
709 goto error_disable_reg;
710
711 st->vref_mv = ret / 1000;
712
713 st->mclk = devm_clk_get(&client->dev, "mclk");
714 if (IS_ERR(st->mclk) && PTR_ERR(st->mclk) != -ENOENT) {
715 ret = PTR_ERR(st->mclk);
716 goto error_disable_reg;
717 }
718
719 if (!IS_ERR(st->mclk)) {
720 ret = clk_prepare_enable(st->mclk);
721 if (ret < 0)
722 goto error_disable_reg;
723 ext_clk_hz = clk_get_rate(st->mclk);
724 }
725
726 if (ext_clk_hz) {
727 st->mclk_hz = ext_clk_hz;
728 st->ctrl_lb = AD5933_CTRL_EXT_SYSCLK;
729 } else {
730 st->mclk_hz = AD5933_INT_OSC_FREQ_Hz;
731 st->ctrl_lb = AD5933_CTRL_INT_SYSCLK;
732 }
733
734 ad5933_calc_out_ranges(st);
735 INIT_DELAYED_WORK(&st->work, ad5933_work);
736 st->poll_time_jiffies = msecs_to_jiffies(AD5933_POLL_TIME_ms);
737
738 indio_dev->dev.parent = &client->dev;
739 indio_dev->info = &ad5933_info;
740 indio_dev->name = id->name;
741 indio_dev->modes = (INDIO_BUFFER_SOFTWARE | INDIO_DIRECT_MODE);
742 indio_dev->channels = ad5933_channels;
743 indio_dev->num_channels = ARRAY_SIZE(ad5933_channels);
744
745 ret = ad5933_register_ring_funcs_and_init(indio_dev);
746 if (ret)
747 goto error_disable_mclk;
748
749 ret = ad5933_setup(st);
750 if (ret)
751 goto error_unreg_ring;
752
753 ret = iio_device_register(indio_dev);
754 if (ret)
755 goto error_unreg_ring;
756
757 return 0;
758
759 error_unreg_ring:
760 iio_kfifo_free(indio_dev->buffer);
761 error_disable_mclk:
762 clk_disable_unprepare(st->mclk);
763 error_disable_reg:
764 regulator_disable(st->reg);
765
766 return ret;
767 }
768
ad5933_remove(struct i2c_client * client)769 static int ad5933_remove(struct i2c_client *client)
770 {
771 struct iio_dev *indio_dev = i2c_get_clientdata(client);
772 struct ad5933_state *st = iio_priv(indio_dev);
773
774 iio_device_unregister(indio_dev);
775 iio_kfifo_free(indio_dev->buffer);
776 regulator_disable(st->reg);
777 clk_disable_unprepare(st->mclk);
778
779 return 0;
780 }
781
782 static const struct i2c_device_id ad5933_id[] = {
783 { "ad5933", 0 },
784 { "ad5934", 0 },
785 {}
786 };
787
788 MODULE_DEVICE_TABLE(i2c, ad5933_id);
789
790 static const struct of_device_id ad5933_of_match[] = {
791 { .compatible = "adi,ad5933" },
792 { .compatible = "adi,ad5934" },
793 { },
794 };
795
796 MODULE_DEVICE_TABLE(of, ad5933_of_match);
797
798 static struct i2c_driver ad5933_driver = {
799 .driver = {
800 .name = "ad5933",
801 .of_match_table = ad5933_of_match,
802 },
803 .probe = ad5933_probe,
804 .remove = ad5933_remove,
805 .id_table = ad5933_id,
806 };
807 module_i2c_driver(ad5933_driver);
808
809 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
810 MODULE_DESCRIPTION("Analog Devices AD5933 Impedance Conv. Network Analyzer");
811 MODULE_LICENSE("GPL v2");
812
