xref: /kernel/linux/linux-5.10/drivers/iio/dac/ad5755.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AD5755, AD5755-1, AD5757, AD5735, AD5737 Digital to analog converters driver
4 *
5 * Copyright 2012 Analog Devices Inc.
6 */
7
8#include <linux/device.h>
9#include <linux/err.h>
10#include <linux/module.h>
11#include <linux/kernel.h>
12#include <linux/spi/spi.h>
13#include <linux/slab.h>
14#include <linux/sysfs.h>
15#include <linux/delay.h>
16#include <linux/of.h>
17#include <linux/iio/iio.h>
18#include <linux/iio/sysfs.h>
19#include <linux/platform_data/ad5755.h>
20
21#define AD5755_NUM_CHANNELS 4
22
23#define AD5755_ADDR(x)			((x) << 16)
24
25#define AD5755_WRITE_REG_DATA(chan)	(chan)
26#define AD5755_WRITE_REG_GAIN(chan)	(0x08 | (chan))
27#define AD5755_WRITE_REG_OFFSET(chan)	(0x10 | (chan))
28#define AD5755_WRITE_REG_CTRL(chan)	(0x1c | (chan))
29
30#define AD5755_READ_REG_DATA(chan)	(chan)
31#define AD5755_READ_REG_CTRL(chan)	(0x4 | (chan))
32#define AD5755_READ_REG_GAIN(chan)	(0x8 | (chan))
33#define AD5755_READ_REG_OFFSET(chan)	(0xc | (chan))
34#define AD5755_READ_REG_CLEAR(chan)	(0x10 | (chan))
35#define AD5755_READ_REG_SLEW(chan)	(0x14 | (chan))
36#define AD5755_READ_REG_STATUS		0x18
37#define AD5755_READ_REG_MAIN		0x19
38#define AD5755_READ_REG_DC_DC		0x1a
39
40#define AD5755_CTRL_REG_SLEW	0x0
41#define AD5755_CTRL_REG_MAIN	0x1
42#define AD5755_CTRL_REG_DAC	0x2
43#define AD5755_CTRL_REG_DC_DC	0x3
44#define AD5755_CTRL_REG_SW	0x4
45
46#define AD5755_READ_FLAG 0x800000
47
48#define AD5755_NOOP 0x1CE000
49
50#define AD5755_DAC_INT_EN			BIT(8)
51#define AD5755_DAC_CLR_EN			BIT(7)
52#define AD5755_DAC_OUT_EN			BIT(6)
53#define AD5755_DAC_INT_CURRENT_SENSE_RESISTOR	BIT(5)
54#define AD5755_DAC_DC_DC_EN			BIT(4)
55#define AD5755_DAC_VOLTAGE_OVERRANGE_EN		BIT(3)
56
57#define AD5755_DC_DC_MAXV			0
58#define AD5755_DC_DC_FREQ_SHIFT			2
59#define AD5755_DC_DC_PHASE_SHIFT		4
60#define AD5755_EXT_DC_DC_COMP_RES		BIT(6)
61
62#define AD5755_SLEW_STEP_SIZE_SHIFT		0
63#define AD5755_SLEW_RATE_SHIFT			3
64#define AD5755_SLEW_ENABLE			BIT(12)
65
66/**
67 * struct ad5755_chip_info - chip specific information
68 * @channel_template:	channel specification
69 * @calib_shift:	shift for the calibration data registers
70 * @has_voltage_out:	whether the chip has voltage outputs
71 */
72struct ad5755_chip_info {
73	const struct iio_chan_spec channel_template;
74	unsigned int calib_shift;
75	bool has_voltage_out;
76};
77
78/**
79 * struct ad5755_state - driver instance specific data
80 * @spi:	spi device the driver is attached to
81 * @chip_info:	chip model specific constants, available modes etc
82 * @pwr_down:	bitmask which contains  hether a channel is powered down or not
83 * @ctrl:	software shadow of the channel ctrl registers
84 * @channels:	iio channel spec for the device
85 * @lock:	lock to protect the data buffer during SPI ops
86 * @data:	spi transfer buffers
87 */
88struct ad5755_state {
89	struct spi_device		*spi;
90	const struct ad5755_chip_info	*chip_info;
91	unsigned int			pwr_down;
92	unsigned int			ctrl[AD5755_NUM_CHANNELS];
93	struct iio_chan_spec		channels[AD5755_NUM_CHANNELS];
94	struct mutex			lock;
95
96	/*
97	 * DMA (thus cache coherency maintenance) requires the
98	 * transfer buffers to live in their own cache lines.
99	 */
100
101	union {
102		__be32 d32;
103		u8 d8[4];
104	} data[2] ____cacheline_aligned;
105};
106
107enum ad5755_type {
108	ID_AD5755,
109	ID_AD5757,
110	ID_AD5735,
111	ID_AD5737,
112};
113
114#ifdef CONFIG_OF
115static const int ad5755_dcdc_freq_table[][2] = {
116	{ 250000, AD5755_DC_DC_FREQ_250kHZ },
117	{ 410000, AD5755_DC_DC_FREQ_410kHZ },
118	{ 650000, AD5755_DC_DC_FREQ_650kHZ }
119};
120
121static const int ad5755_dcdc_maxv_table[][2] = {
122	{ 23000000, AD5755_DC_DC_MAXV_23V },
123	{ 24500000, AD5755_DC_DC_MAXV_24V5 },
124	{ 27000000, AD5755_DC_DC_MAXV_27V },
125	{ 29500000, AD5755_DC_DC_MAXV_29V5 },
126};
127
128static const int ad5755_slew_rate_table[][2] = {
129	{ 64000, AD5755_SLEW_RATE_64k },
130	{ 32000, AD5755_SLEW_RATE_32k },
131	{ 16000, AD5755_SLEW_RATE_16k },
132	{ 8000, AD5755_SLEW_RATE_8k },
133	{ 4000, AD5755_SLEW_RATE_4k },
134	{ 2000, AD5755_SLEW_RATE_2k },
135	{ 1000, AD5755_SLEW_RATE_1k },
136	{ 500, AD5755_SLEW_RATE_500 },
137	{ 250, AD5755_SLEW_RATE_250 },
138	{ 125, AD5755_SLEW_RATE_125 },
139	{ 64, AD5755_SLEW_RATE_64 },
140	{ 32, AD5755_SLEW_RATE_32 },
141	{ 16, AD5755_SLEW_RATE_16 },
142	{ 8, AD5755_SLEW_RATE_8 },
143	{ 4, AD5755_SLEW_RATE_4 },
144	{ 0, AD5755_SLEW_RATE_0_5 },
145};
146
147static const int ad5755_slew_step_table[][2] = {
148	{ 256, AD5755_SLEW_STEP_SIZE_256 },
149	{ 128, AD5755_SLEW_STEP_SIZE_128 },
150	{ 64, AD5755_SLEW_STEP_SIZE_64 },
151	{ 32, AD5755_SLEW_STEP_SIZE_32 },
152	{ 16, AD5755_SLEW_STEP_SIZE_16 },
153	{ 4, AD5755_SLEW_STEP_SIZE_4 },
154	{ 2, AD5755_SLEW_STEP_SIZE_2 },
155	{ 1, AD5755_SLEW_STEP_SIZE_1 },
156};
157#endif
158
159static int ad5755_write_unlocked(struct iio_dev *indio_dev,
160	unsigned int reg, unsigned int val)
161{
162	struct ad5755_state *st = iio_priv(indio_dev);
163
164	st->data[0].d32 = cpu_to_be32((reg << 16) | val);
165
166	return spi_write(st->spi, &st->data[0].d8[1], 3);
167}
168
169static int ad5755_write_ctrl_unlocked(struct iio_dev *indio_dev,
170	unsigned int channel, unsigned int reg, unsigned int val)
171{
172	return ad5755_write_unlocked(indio_dev,
173		AD5755_WRITE_REG_CTRL(channel), (reg << 13) | val);
174}
175
176static int ad5755_write(struct iio_dev *indio_dev, unsigned int reg,
177	unsigned int val)
178{
179	struct ad5755_state *st = iio_priv(indio_dev);
180	int ret;
181
182	mutex_lock(&st->lock);
183	ret = ad5755_write_unlocked(indio_dev, reg, val);
184	mutex_unlock(&st->lock);
185
186	return ret;
187}
188
189static int ad5755_write_ctrl(struct iio_dev *indio_dev, unsigned int channel,
190	unsigned int reg, unsigned int val)
191{
192	struct ad5755_state *st = iio_priv(indio_dev);
193	int ret;
194
195	mutex_lock(&st->lock);
196	ret = ad5755_write_ctrl_unlocked(indio_dev, channel, reg, val);
197	mutex_unlock(&st->lock);
198
199	return ret;
200}
201
202static int ad5755_read(struct iio_dev *indio_dev, unsigned int addr)
203{
204	struct ad5755_state *st = iio_priv(indio_dev);
205	int ret;
206	struct spi_transfer t[] = {
207		{
208			.tx_buf = &st->data[0].d8[1],
209			.len = 3,
210			.cs_change = 1,
211		}, {
212			.tx_buf = &st->data[1].d8[1],
213			.rx_buf = &st->data[1].d8[1],
214			.len = 3,
215		},
216	};
217
218	mutex_lock(&st->lock);
219
220	st->data[0].d32 = cpu_to_be32(AD5755_READ_FLAG | (addr << 16));
221	st->data[1].d32 = cpu_to_be32(AD5755_NOOP);
222
223	ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
224	if (ret >= 0)
225		ret = be32_to_cpu(st->data[1].d32) & 0xffff;
226
227	mutex_unlock(&st->lock);
228
229	return ret;
230}
231
232static int ad5755_update_dac_ctrl(struct iio_dev *indio_dev,
233	unsigned int channel, unsigned int set, unsigned int clr)
234{
235	struct ad5755_state *st = iio_priv(indio_dev);
236	int ret;
237
238	st->ctrl[channel] |= set;
239	st->ctrl[channel] &= ~clr;
240
241	ret = ad5755_write_ctrl_unlocked(indio_dev, channel,
242		AD5755_CTRL_REG_DAC, st->ctrl[channel]);
243
244	return ret;
245}
246
247static int ad5755_set_channel_pwr_down(struct iio_dev *indio_dev,
248	unsigned int channel, bool pwr_down)
249{
250	struct ad5755_state *st = iio_priv(indio_dev);
251	unsigned int mask = BIT(channel);
252
253	mutex_lock(&st->lock);
254
255	if ((bool)(st->pwr_down & mask) == pwr_down)
256		goto out_unlock;
257
258	if (!pwr_down) {
259		st->pwr_down &= ~mask;
260		ad5755_update_dac_ctrl(indio_dev, channel,
261			AD5755_DAC_INT_EN | AD5755_DAC_DC_DC_EN, 0);
262		udelay(200);
263		ad5755_update_dac_ctrl(indio_dev, channel,
264			AD5755_DAC_OUT_EN, 0);
265	} else {
266		st->pwr_down |= mask;
267		ad5755_update_dac_ctrl(indio_dev, channel,
268			0, AD5755_DAC_INT_EN | AD5755_DAC_OUT_EN |
269				AD5755_DAC_DC_DC_EN);
270	}
271
272out_unlock:
273	mutex_unlock(&st->lock);
274
275	return 0;
276}
277
278static const int ad5755_min_max_table[][2] = {
279	[AD5755_MODE_VOLTAGE_0V_5V] = { 0, 5000 },
280	[AD5755_MODE_VOLTAGE_0V_10V] = { 0, 10000 },
281	[AD5755_MODE_VOLTAGE_PLUSMINUS_5V] = { -5000, 5000 },
282	[AD5755_MODE_VOLTAGE_PLUSMINUS_10V] = { -10000, 10000 },
283	[AD5755_MODE_CURRENT_4mA_20mA] = { 4, 20 },
284	[AD5755_MODE_CURRENT_0mA_20mA] = { 0, 20 },
285	[AD5755_MODE_CURRENT_0mA_24mA] = { 0, 24 },
286};
287
288static void ad5755_get_min_max(struct ad5755_state *st,
289	struct iio_chan_spec const *chan, int *min, int *max)
290{
291	enum ad5755_mode mode = st->ctrl[chan->channel] & 7;
292	*min = ad5755_min_max_table[mode][0];
293	*max = ad5755_min_max_table[mode][1];
294}
295
296static inline int ad5755_get_offset(struct ad5755_state *st,
297	struct iio_chan_spec const *chan)
298{
299	int min, max;
300
301	ad5755_get_min_max(st, chan, &min, &max);
302	return (min * (1 << chan->scan_type.realbits)) / (max - min);
303}
304
305static int ad5755_chan_reg_info(struct ad5755_state *st,
306	struct iio_chan_spec const *chan, long info, bool write,
307	unsigned int *reg, unsigned int *shift, unsigned int *offset)
308{
309	switch (info) {
310	case IIO_CHAN_INFO_RAW:
311		if (write)
312			*reg = AD5755_WRITE_REG_DATA(chan->address);
313		else
314			*reg = AD5755_READ_REG_DATA(chan->address);
315		*shift = chan->scan_type.shift;
316		*offset = 0;
317		break;
318	case IIO_CHAN_INFO_CALIBBIAS:
319		if (write)
320			*reg = AD5755_WRITE_REG_OFFSET(chan->address);
321		else
322			*reg = AD5755_READ_REG_OFFSET(chan->address);
323		*shift = st->chip_info->calib_shift;
324		*offset = 32768;
325		break;
326	case IIO_CHAN_INFO_CALIBSCALE:
327		if (write)
328			*reg =  AD5755_WRITE_REG_GAIN(chan->address);
329		else
330			*reg =  AD5755_READ_REG_GAIN(chan->address);
331		*shift = st->chip_info->calib_shift;
332		*offset = 0;
333		break;
334	default:
335		return -EINVAL;
336	}
337
338	return 0;
339}
340
341static int ad5755_read_raw(struct iio_dev *indio_dev,
342	const struct iio_chan_spec *chan, int *val, int *val2, long info)
343{
344	struct ad5755_state *st = iio_priv(indio_dev);
345	unsigned int reg, shift, offset;
346	int min, max;
347	int ret;
348
349	switch (info) {
350	case IIO_CHAN_INFO_SCALE:
351		ad5755_get_min_max(st, chan, &min, &max);
352		*val = max - min;
353		*val2 = chan->scan_type.realbits;
354		return IIO_VAL_FRACTIONAL_LOG2;
355	case IIO_CHAN_INFO_OFFSET:
356		*val = ad5755_get_offset(st, chan);
357		return IIO_VAL_INT;
358	default:
359		ret = ad5755_chan_reg_info(st, chan, info, false,
360						&reg, &shift, &offset);
361		if (ret)
362			return ret;
363
364		ret = ad5755_read(indio_dev, reg);
365		if (ret < 0)
366			return ret;
367
368		*val = (ret - offset) >> shift;
369
370		return IIO_VAL_INT;
371	}
372
373	return -EINVAL;
374}
375
376static int ad5755_write_raw(struct iio_dev *indio_dev,
377	const struct iio_chan_spec *chan, int val, int val2, long info)
378{
379	struct ad5755_state *st = iio_priv(indio_dev);
380	unsigned int shift, reg, offset;
381	int ret;
382
383	ret = ad5755_chan_reg_info(st, chan, info, true,
384					&reg, &shift, &offset);
385	if (ret)
386		return ret;
387
388	val <<= shift;
389	val += offset;
390
391	if (val < 0 || val > 0xffff)
392		return -EINVAL;
393
394	return ad5755_write(indio_dev, reg, val);
395}
396
397static ssize_t ad5755_read_powerdown(struct iio_dev *indio_dev, uintptr_t priv,
398	const struct iio_chan_spec *chan, char *buf)
399{
400	struct ad5755_state *st = iio_priv(indio_dev);
401
402	return sprintf(buf, "%d\n",
403		       (bool)(st->pwr_down & (1 << chan->channel)));
404}
405
406static ssize_t ad5755_write_powerdown(struct iio_dev *indio_dev, uintptr_t priv,
407	struct iio_chan_spec const *chan, const char *buf, size_t len)
408{
409	bool pwr_down;
410	int ret;
411
412	ret = strtobool(buf, &pwr_down);
413	if (ret)
414		return ret;
415
416	ret = ad5755_set_channel_pwr_down(indio_dev, chan->channel, pwr_down);
417	return ret ? ret : len;
418}
419
420static const struct iio_info ad5755_info = {
421	.read_raw = ad5755_read_raw,
422	.write_raw = ad5755_write_raw,
423};
424
425static const struct iio_chan_spec_ext_info ad5755_ext_info[] = {
426	{
427		.name = "powerdown",
428		.read = ad5755_read_powerdown,
429		.write = ad5755_write_powerdown,
430		.shared = IIO_SEPARATE,
431	},
432	{ },
433};
434
435#define AD5755_CHANNEL(_bits) {					\
436	.indexed = 1,						\
437	.output = 1,						\
438	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
439		BIT(IIO_CHAN_INFO_SCALE) |			\
440		BIT(IIO_CHAN_INFO_OFFSET) |			\
441		BIT(IIO_CHAN_INFO_CALIBSCALE) |			\
442		BIT(IIO_CHAN_INFO_CALIBBIAS),			\
443	.scan_type = {						\
444		.sign = 'u',					\
445		.realbits = (_bits),				\
446		.storagebits = 16,				\
447		.shift = 16 - (_bits),				\
448	},							\
449	.ext_info = ad5755_ext_info,				\
450}
451
452static const struct ad5755_chip_info ad5755_chip_info_tbl[] = {
453	[ID_AD5735] = {
454		.channel_template = AD5755_CHANNEL(14),
455		.has_voltage_out = true,
456		.calib_shift = 4,
457	},
458	[ID_AD5737] = {
459		.channel_template = AD5755_CHANNEL(14),
460		.has_voltage_out = false,
461		.calib_shift = 4,
462	},
463	[ID_AD5755] = {
464		.channel_template = AD5755_CHANNEL(16),
465		.has_voltage_out = true,
466		.calib_shift = 0,
467	},
468	[ID_AD5757] = {
469		.channel_template = AD5755_CHANNEL(16),
470		.has_voltage_out = false,
471		.calib_shift = 0,
472	},
473};
474
475static bool ad5755_is_valid_mode(struct ad5755_state *st, enum ad5755_mode mode)
476{
477	switch (mode) {
478	case AD5755_MODE_VOLTAGE_0V_5V:
479	case AD5755_MODE_VOLTAGE_0V_10V:
480	case AD5755_MODE_VOLTAGE_PLUSMINUS_5V:
481	case AD5755_MODE_VOLTAGE_PLUSMINUS_10V:
482		return st->chip_info->has_voltage_out;
483	case AD5755_MODE_CURRENT_4mA_20mA:
484	case AD5755_MODE_CURRENT_0mA_20mA:
485	case AD5755_MODE_CURRENT_0mA_24mA:
486		return true;
487	default:
488		return false;
489	}
490}
491
492static int ad5755_setup_pdata(struct iio_dev *indio_dev,
493			      const struct ad5755_platform_data *pdata)
494{
495	struct ad5755_state *st = iio_priv(indio_dev);
496	unsigned int val;
497	unsigned int i;
498	int ret;
499
500	if (pdata->dc_dc_phase > AD5755_DC_DC_PHASE_90_DEGREE ||
501		pdata->dc_dc_freq > AD5755_DC_DC_FREQ_650kHZ ||
502		pdata->dc_dc_maxv > AD5755_DC_DC_MAXV_29V5)
503		return -EINVAL;
504
505	val = pdata->dc_dc_maxv << AD5755_DC_DC_MAXV;
506	val |= pdata->dc_dc_freq << AD5755_DC_DC_FREQ_SHIFT;
507	val |= pdata->dc_dc_phase << AD5755_DC_DC_PHASE_SHIFT;
508	if (pdata->ext_dc_dc_compenstation_resistor)
509		val |= AD5755_EXT_DC_DC_COMP_RES;
510
511	ret = ad5755_write_ctrl(indio_dev, 0, AD5755_CTRL_REG_DC_DC, val);
512	if (ret < 0)
513		return ret;
514
515	for (i = 0; i < ARRAY_SIZE(pdata->dac); ++i) {
516		val = pdata->dac[i].slew.step_size <<
517			AD5755_SLEW_STEP_SIZE_SHIFT;
518		val |= pdata->dac[i].slew.rate <<
519			AD5755_SLEW_RATE_SHIFT;
520		if (pdata->dac[i].slew.enable)
521			val |= AD5755_SLEW_ENABLE;
522
523		ret = ad5755_write_ctrl(indio_dev, i,
524					AD5755_CTRL_REG_SLEW, val);
525		if (ret < 0)
526			return ret;
527	}
528
529	for (i = 0; i < ARRAY_SIZE(pdata->dac); ++i) {
530		if (!ad5755_is_valid_mode(st, pdata->dac[i].mode))
531			return -EINVAL;
532
533		val = 0;
534		if (!pdata->dac[i].ext_current_sense_resistor)
535			val |= AD5755_DAC_INT_CURRENT_SENSE_RESISTOR;
536		if (pdata->dac[i].enable_voltage_overrange)
537			val |= AD5755_DAC_VOLTAGE_OVERRANGE_EN;
538		val |= pdata->dac[i].mode;
539
540		ret = ad5755_update_dac_ctrl(indio_dev, i, val, 0);
541		if (ret < 0)
542			return ret;
543	}
544
545	return 0;
546}
547
548static bool ad5755_is_voltage_mode(enum ad5755_mode mode)
549{
550	switch (mode) {
551	case AD5755_MODE_VOLTAGE_0V_5V:
552	case AD5755_MODE_VOLTAGE_0V_10V:
553	case AD5755_MODE_VOLTAGE_PLUSMINUS_5V:
554	case AD5755_MODE_VOLTAGE_PLUSMINUS_10V:
555		return true;
556	default:
557		return false;
558	}
559}
560
561static int ad5755_init_channels(struct iio_dev *indio_dev,
562				const struct ad5755_platform_data *pdata)
563{
564	struct ad5755_state *st = iio_priv(indio_dev);
565	struct iio_chan_spec *channels = st->channels;
566	unsigned int i;
567
568	for (i = 0; i < AD5755_NUM_CHANNELS; ++i) {
569		channels[i] = st->chip_info->channel_template;
570		channels[i].channel = i;
571		channels[i].address = i;
572		if (pdata && ad5755_is_voltage_mode(pdata->dac[i].mode))
573			channels[i].type = IIO_VOLTAGE;
574		else
575			channels[i].type = IIO_CURRENT;
576	}
577
578	indio_dev->channels = channels;
579
580	return 0;
581}
582
583#define AD5755_DEFAULT_DAC_PDATA { \
584		.mode = AD5755_MODE_CURRENT_4mA_20mA, \
585		.ext_current_sense_resistor = true, \
586		.enable_voltage_overrange = false, \
587		.slew = { \
588			.enable = false, \
589			.rate = AD5755_SLEW_RATE_64k, \
590			.step_size = AD5755_SLEW_STEP_SIZE_1, \
591		}, \
592	}
593
594static const struct ad5755_platform_data ad5755_default_pdata = {
595	.ext_dc_dc_compenstation_resistor = false,
596	.dc_dc_phase = AD5755_DC_DC_PHASE_ALL_SAME_EDGE,
597	.dc_dc_freq = AD5755_DC_DC_FREQ_410kHZ,
598	.dc_dc_maxv = AD5755_DC_DC_MAXV_23V,
599	.dac = {
600		[0] = AD5755_DEFAULT_DAC_PDATA,
601		[1] = AD5755_DEFAULT_DAC_PDATA,
602		[2] = AD5755_DEFAULT_DAC_PDATA,
603		[3] = AD5755_DEFAULT_DAC_PDATA,
604	},
605};
606
607#ifdef CONFIG_OF
608static struct ad5755_platform_data *ad5755_parse_dt(struct device *dev)
609{
610	struct device_node *np = dev->of_node;
611	struct device_node *pp;
612	struct ad5755_platform_data *pdata;
613	unsigned int tmp;
614	unsigned int tmparray[3];
615	int devnr, i;
616
617	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
618	if (!pdata)
619		return NULL;
620
621	pdata->ext_dc_dc_compenstation_resistor =
622	    of_property_read_bool(np, "adi,ext-dc-dc-compenstation-resistor");
623
624	if (!of_property_read_u32(np, "adi,dc-dc-phase", &tmp))
625		pdata->dc_dc_phase = tmp;
626	else
627		pdata->dc_dc_phase = AD5755_DC_DC_PHASE_ALL_SAME_EDGE;
628
629	pdata->dc_dc_freq = AD5755_DC_DC_FREQ_410kHZ;
630	if (!of_property_read_u32(np, "adi,dc-dc-freq-hz", &tmp)) {
631		for (i = 0; i < ARRAY_SIZE(ad5755_dcdc_freq_table); i++) {
632			if (tmp == ad5755_dcdc_freq_table[i][0]) {
633				pdata->dc_dc_freq = ad5755_dcdc_freq_table[i][1];
634				break;
635			}
636		}
637
638		if (i == ARRAY_SIZE(ad5755_dcdc_freq_table))
639			dev_err(dev,
640				"adi,dc-dc-freq out of range selecting 410kHz\n");
641	}
642
643	pdata->dc_dc_maxv = AD5755_DC_DC_MAXV_23V;
644	if (!of_property_read_u32(np, "adi,dc-dc-max-microvolt", &tmp)) {
645		for (i = 0; i < ARRAY_SIZE(ad5755_dcdc_maxv_table); i++) {
646			if (tmp == ad5755_dcdc_maxv_table[i][0]) {
647				pdata->dc_dc_maxv = ad5755_dcdc_maxv_table[i][1];
648				break;
649			}
650		}
651		if (i == ARRAY_SIZE(ad5755_dcdc_maxv_table))
652				dev_err(dev,
653					"adi,dc-dc-maxv out of range selecting 23V\n");
654	}
655
656	devnr = 0;
657	for_each_child_of_node(np, pp) {
658		if (devnr >= AD5755_NUM_CHANNELS) {
659			dev_err(dev,
660				"There are too many channels defined in DT\n");
661			goto error_out;
662		}
663
664		if (!of_property_read_u32(pp, "adi,mode", &tmp))
665			pdata->dac[devnr].mode = tmp;
666		else
667			pdata->dac[devnr].mode = AD5755_MODE_CURRENT_4mA_20mA;
668
669		pdata->dac[devnr].ext_current_sense_resistor =
670		    of_property_read_bool(pp, "adi,ext-current-sense-resistor");
671
672		pdata->dac[devnr].enable_voltage_overrange =
673		    of_property_read_bool(pp, "adi,enable-voltage-overrange");
674
675		if (!of_property_read_u32_array(pp, "adi,slew", tmparray, 3)) {
676			pdata->dac[devnr].slew.enable = tmparray[0];
677
678			pdata->dac[devnr].slew.rate = AD5755_SLEW_RATE_64k;
679			for (i = 0; i < ARRAY_SIZE(ad5755_slew_rate_table); i++) {
680				if (tmparray[1] == ad5755_slew_rate_table[i][0]) {
681					pdata->dac[devnr].slew.rate =
682						ad5755_slew_rate_table[i][1];
683					break;
684				}
685			}
686			if (i == ARRAY_SIZE(ad5755_slew_rate_table))
687				dev_err(dev,
688					"channel %d slew rate out of range selecting 64kHz\n",
689					devnr);
690
691			pdata->dac[devnr].slew.step_size = AD5755_SLEW_STEP_SIZE_1;
692			for (i = 0; i < ARRAY_SIZE(ad5755_slew_step_table); i++) {
693				if (tmparray[2] == ad5755_slew_step_table[i][0]) {
694					pdata->dac[devnr].slew.step_size =
695						ad5755_slew_step_table[i][1];
696					break;
697				}
698			}
699			if (i == ARRAY_SIZE(ad5755_slew_step_table))
700				dev_err(dev,
701					"channel %d slew step size out of range selecting 1 LSB\n",
702					devnr);
703		} else {
704			pdata->dac[devnr].slew.enable = false;
705			pdata->dac[devnr].slew.rate = AD5755_SLEW_RATE_64k;
706			pdata->dac[devnr].slew.step_size =
707			    AD5755_SLEW_STEP_SIZE_1;
708		}
709		devnr++;
710	}
711
712	return pdata;
713
714 error_out:
715	devm_kfree(dev, pdata);
716	return NULL;
717}
718#else
719static
720struct ad5755_platform_data *ad5755_parse_dt(struct device *dev)
721{
722	return NULL;
723}
724#endif
725
726static int ad5755_probe(struct spi_device *spi)
727{
728	enum ad5755_type type = spi_get_device_id(spi)->driver_data;
729	const struct ad5755_platform_data *pdata = dev_get_platdata(&spi->dev);
730	struct iio_dev *indio_dev;
731	struct ad5755_state *st;
732	int ret;
733
734	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
735	if (indio_dev == NULL) {
736		dev_err(&spi->dev, "Failed to allocate iio device\n");
737		return  -ENOMEM;
738	}
739
740	st = iio_priv(indio_dev);
741	spi_set_drvdata(spi, indio_dev);
742
743	st->chip_info = &ad5755_chip_info_tbl[type];
744	st->spi = spi;
745	st->pwr_down = 0xf;
746
747	indio_dev->name = spi_get_device_id(spi)->name;
748	indio_dev->info = &ad5755_info;
749	indio_dev->modes = INDIO_DIRECT_MODE;
750	indio_dev->num_channels = AD5755_NUM_CHANNELS;
751
752	mutex_init(&st->lock);
753
754	if (spi->dev.of_node)
755		pdata = ad5755_parse_dt(&spi->dev);
756	else
757		pdata = spi->dev.platform_data;
758
759	if (!pdata) {
760		dev_warn(&spi->dev, "no platform data? using default\n");
761		pdata = &ad5755_default_pdata;
762	}
763
764	ret = ad5755_init_channels(indio_dev, pdata);
765	if (ret)
766		return ret;
767
768	ret = ad5755_setup_pdata(indio_dev, pdata);
769	if (ret)
770		return ret;
771
772	return devm_iio_device_register(&spi->dev, indio_dev);
773}
774
775static const struct spi_device_id ad5755_id[] = {
776	{ "ad5755", ID_AD5755 },
777	{ "ad5755-1", ID_AD5755 },
778	{ "ad5757", ID_AD5757 },
779	{ "ad5735", ID_AD5735 },
780	{ "ad5737", ID_AD5737 },
781	{}
782};
783MODULE_DEVICE_TABLE(spi, ad5755_id);
784
785static const struct of_device_id ad5755_of_match[] = {
786	{ .compatible = "adi,ad5755" },
787	{ .compatible = "adi,ad5755-1" },
788	{ .compatible = "adi,ad5757" },
789	{ .compatible = "adi,ad5735" },
790	{ .compatible = "adi,ad5737" },
791	{ }
792};
793MODULE_DEVICE_TABLE(of, ad5755_of_match);
794
795static struct spi_driver ad5755_driver = {
796	.driver = {
797		.name = "ad5755",
798	},
799	.probe = ad5755_probe,
800	.id_table = ad5755_id,
801};
802module_spi_driver(ad5755_driver);
803
804MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
805MODULE_DESCRIPTION("Analog Devices AD5755/55-1/57/35/37 DAC");
806MODULE_LICENSE("GPL v2");
807