1/*
2 * Copyright (c) 2012-2014, The Linux Foundation. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 and
6 * only version 2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11 * GNU General Public License for more details.
12 */
13
14#include <linux/bitops.h>
15#include <linux/completion.h>
16#include <linux/delay.h>
17#include <linux/err.h>
18#include <linux/iio/iio.h>
19#include <linux/interrupt.h>
20#include <linux/kernel.h>
21#include <linux/math64.h>
22#include <linux/module.h>
23#include <linux/of.h>
24#include <linux/platform_device.h>
25#include <linux/regmap.h>
26#include <linux/slab.h>
27#include <linux/log2.h>
28
29#include <dt-bindings/iio/qcom,spmi-vadc.h>
30
31/* VADC register and bit definitions */
32#define VADC_REVISION2				0x1
33#define VADC_REVISION2_SUPPORTED_VADC		1
34
35#define VADC_PERPH_TYPE				0x4
36#define VADC_PERPH_TYPE_ADC			8
37
38#define VADC_PERPH_SUBTYPE			0x5
39#define VADC_PERPH_SUBTYPE_VADC			1
40
41#define VADC_STATUS1				0x8
42#define VADC_STATUS1_OP_MODE			4
43#define VADC_STATUS1_REQ_STS			BIT(1)
44#define VADC_STATUS1_EOC			BIT(0)
45#define VADC_STATUS1_REQ_STS_EOC_MASK		0x3
46
47#define VADC_MODE_CTL				0x40
48#define VADC_OP_MODE_SHIFT			3
49#define VADC_OP_MODE_NORMAL			0
50#define VADC_AMUX_TRIM_EN			BIT(1)
51#define VADC_ADC_TRIM_EN			BIT(0)
52
53#define VADC_EN_CTL1				0x46
54#define VADC_EN_CTL1_SET			BIT(7)
55
56#define VADC_ADC_CH_SEL_CTL			0x48
57
58#define VADC_ADC_DIG_PARAM			0x50
59#define VADC_ADC_DIG_DEC_RATIO_SEL_SHIFT	2
60
61#define VADC_HW_SETTLE_DELAY			0x51
62
63#define VADC_CONV_REQ				0x52
64#define VADC_CONV_REQ_SET			BIT(7)
65
66#define VADC_FAST_AVG_CTL			0x5a
67#define VADC_FAST_AVG_EN			0x5b
68#define VADC_FAST_AVG_EN_SET			BIT(7)
69
70#define VADC_ACCESS				0xd0
71#define VADC_ACCESS_DATA			0xa5
72
73#define VADC_PERH_RESET_CTL3			0xda
74#define VADC_FOLLOW_WARM_RB			BIT(2)
75
76#define VADC_DATA				0x60	/* 16 bits */
77
78#define VADC_CONV_TIME_MIN_US			2000
79#define VADC_CONV_TIME_MAX_US			2100
80
81/* Min ADC code represents 0V */
82#define VADC_MIN_ADC_CODE			0x6000
83/* Max ADC code represents full-scale range of 1.8V */
84#define VADC_MAX_ADC_CODE			0xa800
85
86#define VADC_ABSOLUTE_RANGE_UV			625000
87#define VADC_RATIOMETRIC_RANGE_UV		1800000
88
89#define VADC_DEF_PRESCALING			0 /* 1:1 */
90#define VADC_DEF_DECIMATION			0 /* 512 */
91#define VADC_DEF_HW_SETTLE_TIME			0 /* 0 us */
92#define VADC_DEF_AVG_SAMPLES			0 /* 1 sample */
93#define VADC_DEF_CALIB_TYPE			VADC_CALIB_ABSOLUTE
94
95#define VADC_DECIMATION_MIN			512
96#define VADC_DECIMATION_MAX			4096
97
98#define VADC_HW_SETTLE_DELAY_MAX		10000
99#define VADC_AVG_SAMPLES_MAX			512
100
101#define KELVINMIL_CELSIUSMIL			273150
102
103#define VADC_CHAN_MIN			VADC_USBIN
104#define VADC_CHAN_MAX			VADC_LR_MUX3_BUF_PU1_PU2_XO_THERM
105
106/*
107 * VADC_CALIB_ABSOLUTE: uses the 625mV and 1.25V as reference channels.
108 * VADC_CALIB_RATIOMETRIC: uses the reference voltage (1.8V) and GND for
109 * calibration.
110 */
111enum vadc_calibration {
112	VADC_CALIB_ABSOLUTE = 0,
113	VADC_CALIB_RATIOMETRIC
114};
115
116/**
117 * struct vadc_linear_graph - Represent ADC characteristics.
118 * @dy: numerator slope to calculate the gain.
119 * @dx: denominator slope to calculate the gain.
120 * @gnd: A/D word of the ground reference used for the channel.
121 *
122 * Each ADC device has different offset and gain parameters which are
123 * computed to calibrate the device.
124 */
125struct vadc_linear_graph {
126	s32 dy;
127	s32 dx;
128	s32 gnd;
129};
130
131/**
132 * struct vadc_prescale_ratio - Represent scaling ratio for ADC input.
133 * @num: the inverse numerator of the gain applied to the input channel.
134 * @den: the inverse denominator of the gain applied to the input channel.
135 */
136struct vadc_prescale_ratio {
137	u32 num;
138	u32 den;
139};
140
141/**
142 * struct vadc_channel_prop - VADC channel property.
143 * @channel: channel number, refer to the channel list.
144 * @calibration: calibration type.
145 * @decimation: sampling rate supported for the channel.
146 * @prescale: channel scaling performed on the input signal.
147 * @hw_settle_time: the time between AMUX being configured and the
148 *	start of conversion.
149 * @avg_samples: ability to provide single result from the ADC
150 *	that is an average of multiple measurements.
151 */
152struct vadc_channel_prop {
153	unsigned int channel;
154	enum vadc_calibration calibration;
155	unsigned int decimation;
156	unsigned int prescale;
157	unsigned int hw_settle_time;
158	unsigned int avg_samples;
159};
160
161/**
162 * struct vadc_priv - VADC private structure.
163 * @regmap: pointer to struct regmap.
164 * @dev: pointer to struct device.
165 * @base: base address for the ADC peripheral.
166 * @nchannels: number of VADC channels.
167 * @chan_props: array of VADC channel properties.
168 * @iio_chans: array of IIO channels specification.
169 * @are_ref_measured: are reference points measured.
170 * @poll_eoc: use polling instead of interrupt.
171 * @complete: VADC result notification after interrupt is received.
172 * @graph: store parameters for calibration.
173 * @lock: ADC lock for access to the peripheral.
174 */
175struct vadc_priv {
176	struct regmap		 *regmap;
177	struct device		 *dev;
178	u16			 base;
179	unsigned int		 nchannels;
180	struct vadc_channel_prop *chan_props;
181	struct iio_chan_spec	 *iio_chans;
182	bool			 are_ref_measured;
183	bool			 poll_eoc;
184	struct completion	 complete;
185	struct vadc_linear_graph graph[2];
186	struct mutex		 lock;
187};
188
189static const struct vadc_prescale_ratio vadc_prescale_ratios[] = {
190	{.num =  1, .den =  1},
191	{.num =  1, .den =  3},
192	{.num =  1, .den =  4},
193	{.num =  1, .den =  6},
194	{.num =  1, .den = 20},
195	{.num =  1, .den =  8},
196	{.num = 10, .den = 81},
197	{.num =  1, .den = 10}
198};
199
200static int vadc_read(struct vadc_priv *vadc, u16 offset, u8 *data)
201{
202	return regmap_bulk_read(vadc->regmap, vadc->base + offset, data, 1);
203}
204
205static int vadc_write(struct vadc_priv *vadc, u16 offset, u8 data)
206{
207	return regmap_write(vadc->regmap, vadc->base + offset, data);
208}
209
210static int vadc_reset(struct vadc_priv *vadc)
211{
212	u8 data;
213	int ret;
214
215	ret = vadc_write(vadc, VADC_ACCESS, VADC_ACCESS_DATA);
216	if (ret)
217		return ret;
218
219	ret = vadc_read(vadc, VADC_PERH_RESET_CTL3, &data);
220	if (ret)
221		return ret;
222
223	ret = vadc_write(vadc, VADC_ACCESS, VADC_ACCESS_DATA);
224	if (ret)
225		return ret;
226
227	data |= VADC_FOLLOW_WARM_RB;
228
229	return vadc_write(vadc, VADC_PERH_RESET_CTL3, data);
230}
231
232static int vadc_set_state(struct vadc_priv *vadc, bool state)
233{
234	return vadc_write(vadc, VADC_EN_CTL1, state ? VADC_EN_CTL1_SET : 0);
235}
236
237static void vadc_show_status(struct vadc_priv *vadc)
238{
239	u8 mode, sta1, chan, dig, en, req;
240	int ret;
241
242	ret = vadc_read(vadc, VADC_MODE_CTL, &mode);
243	if (ret)
244		return;
245
246	ret = vadc_read(vadc, VADC_ADC_DIG_PARAM, &dig);
247	if (ret)
248		return;
249
250	ret = vadc_read(vadc, VADC_ADC_CH_SEL_CTL, &chan);
251	if (ret)
252		return;
253
254	ret = vadc_read(vadc, VADC_CONV_REQ, &req);
255	if (ret)
256		return;
257
258	ret = vadc_read(vadc, VADC_STATUS1, &sta1);
259	if (ret)
260		return;
261
262	ret = vadc_read(vadc, VADC_EN_CTL1, &en);
263	if (ret)
264		return;
265
266	dev_err(vadc->dev,
267		"mode:%02x en:%02x chan:%02x dig:%02x req:%02x sta1:%02x\n",
268		mode, en, chan, dig, req, sta1);
269}
270
271static int vadc_configure(struct vadc_priv *vadc,
272			  struct vadc_channel_prop *prop)
273{
274	u8 decimation, mode_ctrl;
275	int ret;
276
277	/* Mode selection */
278	mode_ctrl = (VADC_OP_MODE_NORMAL << VADC_OP_MODE_SHIFT) |
279		     VADC_ADC_TRIM_EN | VADC_AMUX_TRIM_EN;
280	ret = vadc_write(vadc, VADC_MODE_CTL, mode_ctrl);
281	if (ret)
282		return ret;
283
284	/* Channel selection */
285	ret = vadc_write(vadc, VADC_ADC_CH_SEL_CTL, prop->channel);
286	if (ret)
287		return ret;
288
289	/* Digital parameter setup */
290	decimation = prop->decimation << VADC_ADC_DIG_DEC_RATIO_SEL_SHIFT;
291	ret = vadc_write(vadc, VADC_ADC_DIG_PARAM, decimation);
292	if (ret)
293		return ret;
294
295	/* HW settle time delay */
296	ret = vadc_write(vadc, VADC_HW_SETTLE_DELAY, prop->hw_settle_time);
297	if (ret)
298		return ret;
299
300	ret = vadc_write(vadc, VADC_FAST_AVG_CTL, prop->avg_samples);
301	if (ret)
302		return ret;
303
304	if (prop->avg_samples)
305		ret = vadc_write(vadc, VADC_FAST_AVG_EN, VADC_FAST_AVG_EN_SET);
306	else
307		ret = vadc_write(vadc, VADC_FAST_AVG_EN, 0);
308
309	return ret;
310}
311
312static int vadc_poll_wait_eoc(struct vadc_priv *vadc, unsigned int interval_us)
313{
314	unsigned int count, retry;
315	u8 sta1;
316	int ret;
317
318	retry = interval_us / VADC_CONV_TIME_MIN_US;
319
320	for (count = 0; count < retry; count++) {
321		ret = vadc_read(vadc, VADC_STATUS1, &sta1);
322		if (ret)
323			return ret;
324
325		sta1 &= VADC_STATUS1_REQ_STS_EOC_MASK;
326		if (sta1 == VADC_STATUS1_EOC)
327			return 0;
328
329		usleep_range(VADC_CONV_TIME_MIN_US, VADC_CONV_TIME_MAX_US);
330	}
331
332	vadc_show_status(vadc);
333
334	return -ETIMEDOUT;
335}
336
337static int vadc_read_result(struct vadc_priv *vadc, u16 *data)
338{
339	int ret;
340
341	ret = regmap_bulk_read(vadc->regmap, vadc->base + VADC_DATA, data, 2);
342	if (ret)
343		return ret;
344
345	*data = clamp_t(u16, *data, VADC_MIN_ADC_CODE, VADC_MAX_ADC_CODE);
346
347	return 0;
348}
349
350static struct vadc_channel_prop *vadc_get_channel(struct vadc_priv *vadc,
351						  unsigned int num)
352{
353	unsigned int i;
354
355	for (i = 0; i < vadc->nchannels; i++)
356		if (vadc->chan_props[i].channel == num)
357			return &vadc->chan_props[i];
358
359	dev_dbg(vadc->dev, "no such channel %02x\n", num);
360
361	return NULL;
362}
363
364static int vadc_do_conversion(struct vadc_priv *vadc,
365			      struct vadc_channel_prop *prop, u16 *data)
366{
367	unsigned int timeout;
368	int ret;
369
370	mutex_lock(&vadc->lock);
371
372	ret = vadc_configure(vadc, prop);
373	if (ret)
374		goto unlock;
375
376	if (!vadc->poll_eoc)
377		reinit_completion(&vadc->complete);
378
379	ret = vadc_set_state(vadc, true);
380	if (ret)
381		goto unlock;
382
383	ret = vadc_write(vadc, VADC_CONV_REQ, VADC_CONV_REQ_SET);
384	if (ret)
385		goto err_disable;
386
387	timeout = BIT(prop->avg_samples) * VADC_CONV_TIME_MIN_US * 2;
388
389	if (vadc->poll_eoc) {
390		ret = vadc_poll_wait_eoc(vadc, timeout);
391	} else {
392		ret = wait_for_completion_timeout(&vadc->complete, timeout);
393		if (!ret) {
394			ret = -ETIMEDOUT;
395			goto err_disable;
396		}
397
398		/* Double check conversion status */
399		ret = vadc_poll_wait_eoc(vadc, VADC_CONV_TIME_MIN_US);
400		if (ret)
401			goto err_disable;
402	}
403
404	ret = vadc_read_result(vadc, data);
405
406err_disable:
407	vadc_set_state(vadc, false);
408	if (ret)
409		dev_err(vadc->dev, "conversion failed\n");
410unlock:
411	mutex_unlock(&vadc->lock);
412	return ret;
413}
414
415static int vadc_measure_ref_points(struct vadc_priv *vadc)
416{
417	struct vadc_channel_prop *prop;
418	u16 read_1, read_2;
419	int ret;
420
421	vadc->graph[VADC_CALIB_RATIOMETRIC].dx = VADC_RATIOMETRIC_RANGE_UV;
422	vadc->graph[VADC_CALIB_ABSOLUTE].dx = VADC_ABSOLUTE_RANGE_UV;
423
424	prop = vadc_get_channel(vadc, VADC_REF_1250MV);
425	ret = vadc_do_conversion(vadc, prop, &read_1);
426	if (ret)
427		goto err;
428
429	/* Try with buffered 625mV channel first */
430	prop = vadc_get_channel(vadc, VADC_SPARE1);
431	if (!prop)
432		prop = vadc_get_channel(vadc, VADC_REF_625MV);
433
434	ret = vadc_do_conversion(vadc, prop, &read_2);
435	if (ret)
436		goto err;
437
438	if (read_1 == read_2) {
439		ret = -EINVAL;
440		goto err;
441	}
442
443	vadc->graph[VADC_CALIB_ABSOLUTE].dy = read_1 - read_2;
444	vadc->graph[VADC_CALIB_ABSOLUTE].gnd = read_2;
445
446	/* Ratiometric calibration */
447	prop = vadc_get_channel(vadc, VADC_VDD_VADC);
448	ret = vadc_do_conversion(vadc, prop, &read_1);
449	if (ret)
450		goto err;
451
452	prop = vadc_get_channel(vadc, VADC_GND_REF);
453	ret = vadc_do_conversion(vadc, prop, &read_2);
454	if (ret)
455		goto err;
456
457	if (read_1 == read_2) {
458		ret = -EINVAL;
459		goto err;
460	}
461
462	vadc->graph[VADC_CALIB_RATIOMETRIC].dy = read_1 - read_2;
463	vadc->graph[VADC_CALIB_RATIOMETRIC].gnd = read_2;
464err:
465	if (ret)
466		dev_err(vadc->dev, "measure reference points failed\n");
467
468	return ret;
469}
470
471static s32 vadc_calibrate(struct vadc_priv *vadc,
472			  const struct vadc_channel_prop *prop, u16 adc_code)
473{
474	const struct vadc_prescale_ratio *prescale;
475	s64 voltage;
476
477	voltage = adc_code - vadc->graph[prop->calibration].gnd;
478	voltage *= vadc->graph[prop->calibration].dx;
479	voltage = div64_s64(voltage, vadc->graph[prop->calibration].dy);
480
481	if (prop->calibration == VADC_CALIB_ABSOLUTE)
482		voltage += vadc->graph[prop->calibration].dx;
483
484	if (voltage < 0)
485		voltage = 0;
486
487	prescale = &vadc_prescale_ratios[prop->prescale];
488
489	voltage = voltage * prescale->den;
490
491	return div64_s64(voltage, prescale->num);
492}
493
494static int vadc_decimation_from_dt(u32 value)
495{
496	if (!is_power_of_2(value) || value < VADC_DECIMATION_MIN ||
497	    value > VADC_DECIMATION_MAX)
498		return -EINVAL;
499
500	return __ffs64(value / VADC_DECIMATION_MIN);
501}
502
503static int vadc_prescaling_from_dt(u32 num, u32 den)
504{
505	unsigned int pre;
506
507	for (pre = 0; pre < ARRAY_SIZE(vadc_prescale_ratios); pre++)
508		if (vadc_prescale_ratios[pre].num == num &&
509		    vadc_prescale_ratios[pre].den == den)
510			break;
511
512	if (pre == ARRAY_SIZE(vadc_prescale_ratios))
513		return -EINVAL;
514
515	return pre;
516}
517
518static int vadc_hw_settle_time_from_dt(u32 value)
519{
520	if ((value <= 1000 && value % 100) || (value > 1000 && value % 2000))
521		return -EINVAL;
522
523	if (value <= 1000)
524		value /= 100;
525	else
526		value = value / 2000 + 10;
527
528	return value;
529}
530
531static int vadc_avg_samples_from_dt(u32 value)
532{
533	if (!is_power_of_2(value) || value > VADC_AVG_SAMPLES_MAX)
534		return -EINVAL;
535
536	return __ffs64(value);
537}
538
539static int vadc_read_raw(struct iio_dev *indio_dev,
540			 struct iio_chan_spec const *chan, int *val, int *val2,
541			 long mask)
542{
543	struct vadc_priv *vadc = iio_priv(indio_dev);
544	struct vadc_channel_prop *prop;
545	u16 adc_code;
546	int ret;
547
548	switch (mask) {
549	case IIO_CHAN_INFO_PROCESSED:
550		prop = &vadc->chan_props[chan->address];
551		ret = vadc_do_conversion(vadc, prop, &adc_code);
552		if (ret)
553			break;
554
555		*val = vadc_calibrate(vadc, prop, adc_code);
556
557		/* 2mV/K, return milli Celsius */
558		*val /= 2;
559		*val -= KELVINMIL_CELSIUSMIL;
560		return IIO_VAL_INT;
561	case IIO_CHAN_INFO_RAW:
562		prop = &vadc->chan_props[chan->address];
563		ret = vadc_do_conversion(vadc, prop, &adc_code);
564		if (ret)
565			break;
566
567		*val = vadc_calibrate(vadc, prop, adc_code);
568		return IIO_VAL_INT;
569	case IIO_CHAN_INFO_SCALE:
570		*val = 0;
571		*val2 = 1000;
572		return IIO_VAL_INT_PLUS_MICRO;
573	default:
574		ret = -EINVAL;
575		break;
576	}
577
578	return ret;
579}
580
581static int vadc_of_xlate(struct iio_dev *indio_dev,
582			 const struct of_phandle_args *iiospec)
583{
584	struct vadc_priv *vadc = iio_priv(indio_dev);
585	unsigned int i;
586
587	for (i = 0; i < vadc->nchannels; i++)
588		if (vadc->iio_chans[i].channel == iiospec->args[0])
589			return i;
590
591	return -EINVAL;
592}
593
594static const struct iio_info vadc_info = {
595	.read_raw = vadc_read_raw,
596	.of_xlate = vadc_of_xlate,
597	.driver_module = THIS_MODULE,
598};
599
600struct vadc_channels {
601	const char *datasheet_name;
602	unsigned int prescale_index;
603	enum iio_chan_type type;
604	long info_mask;
605};
606
607#define VADC_CHAN(_dname, _type, _mask, _pre)				\
608	[VADC_##_dname] = {						\
609		.datasheet_name = __stringify(_dname),			\
610		.prescale_index = _pre,					\
611		.type = _type,						\
612		.info_mask = _mask					\
613	},								\
614
615#define VADC_CHAN_TEMP(_dname, _pre)					\
616	VADC_CHAN(_dname, IIO_TEMP, BIT(IIO_CHAN_INFO_PROCESSED), _pre)	\
617
618#define VADC_CHAN_VOLT(_dname, _pre)					\
619	VADC_CHAN(_dname, IIO_VOLTAGE,					\
620		  BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),	\
621		  _pre)							\
622
623/*
624 * The array represents all possible ADC channels found in the supported PMICs.
625 * Every index in the array is equal to the channel number per datasheet. The
626 * gaps in the array should be treated as reserved channels.
627 */
628static const struct vadc_channels vadc_chans[] = {
629	VADC_CHAN_VOLT(USBIN, 4)
630	VADC_CHAN_VOLT(DCIN, 4)
631	VADC_CHAN_VOLT(VCHG_SNS, 3)
632	VADC_CHAN_VOLT(SPARE1_03, 1)
633	VADC_CHAN_VOLT(USB_ID_MV, 1)
634	VADC_CHAN_VOLT(VCOIN, 1)
635	VADC_CHAN_VOLT(VBAT_SNS, 1)
636	VADC_CHAN_VOLT(VSYS, 1)
637	VADC_CHAN_TEMP(DIE_TEMP, 0)
638	VADC_CHAN_VOLT(REF_625MV, 0)
639	VADC_CHAN_VOLT(REF_1250MV, 0)
640	VADC_CHAN_VOLT(CHG_TEMP, 0)
641	VADC_CHAN_VOLT(SPARE1, 0)
642	VADC_CHAN_VOLT(SPARE2, 0)
643	VADC_CHAN_VOLT(GND_REF, 0)
644	VADC_CHAN_VOLT(VDD_VADC, 0)
645
646	VADC_CHAN_VOLT(P_MUX1_1_1, 0)
647	VADC_CHAN_VOLT(P_MUX2_1_1, 0)
648	VADC_CHAN_VOLT(P_MUX3_1_1, 0)
649	VADC_CHAN_VOLT(P_MUX4_1_1, 0)
650	VADC_CHAN_VOLT(P_MUX5_1_1, 0)
651	VADC_CHAN_VOLT(P_MUX6_1_1, 0)
652	VADC_CHAN_VOLT(P_MUX7_1_1, 0)
653	VADC_CHAN_VOLT(P_MUX8_1_1, 0)
654	VADC_CHAN_VOLT(P_MUX9_1_1, 0)
655	VADC_CHAN_VOLT(P_MUX10_1_1, 0)
656	VADC_CHAN_VOLT(P_MUX11_1_1, 0)
657	VADC_CHAN_VOLT(P_MUX12_1_1, 0)
658	VADC_CHAN_VOLT(P_MUX13_1_1, 0)
659	VADC_CHAN_VOLT(P_MUX14_1_1, 0)
660	VADC_CHAN_VOLT(P_MUX15_1_1, 0)
661	VADC_CHAN_VOLT(P_MUX16_1_1, 0)
662
663	VADC_CHAN_VOLT(P_MUX1_1_3, 1)
664	VADC_CHAN_VOLT(P_MUX2_1_3, 1)
665	VADC_CHAN_VOLT(P_MUX3_1_3, 1)
666	VADC_CHAN_VOLT(P_MUX4_1_3, 1)
667	VADC_CHAN_VOLT(P_MUX5_1_3, 1)
668	VADC_CHAN_VOLT(P_MUX6_1_3, 1)
669	VADC_CHAN_VOLT(P_MUX7_1_3, 1)
670	VADC_CHAN_VOLT(P_MUX8_1_3, 1)
671	VADC_CHAN_VOLT(P_MUX9_1_3, 1)
672	VADC_CHAN_VOLT(P_MUX10_1_3, 1)
673	VADC_CHAN_VOLT(P_MUX11_1_3, 1)
674	VADC_CHAN_VOLT(P_MUX12_1_3, 1)
675	VADC_CHAN_VOLT(P_MUX13_1_3, 1)
676	VADC_CHAN_VOLT(P_MUX14_1_3, 1)
677	VADC_CHAN_VOLT(P_MUX15_1_3, 1)
678	VADC_CHAN_VOLT(P_MUX16_1_3, 1)
679
680	VADC_CHAN_VOLT(LR_MUX1_BAT_THERM, 0)
681	VADC_CHAN_VOLT(LR_MUX2_BAT_ID, 0)
682	VADC_CHAN_VOLT(LR_MUX3_XO_THERM, 0)
683	VADC_CHAN_VOLT(LR_MUX4_AMUX_THM1, 0)
684	VADC_CHAN_VOLT(LR_MUX5_AMUX_THM2, 0)
685	VADC_CHAN_VOLT(LR_MUX6_AMUX_THM3, 0)
686	VADC_CHAN_VOLT(LR_MUX7_HW_ID, 0)
687	VADC_CHAN_VOLT(LR_MUX8_AMUX_THM4, 0)
688	VADC_CHAN_VOLT(LR_MUX9_AMUX_THM5, 0)
689	VADC_CHAN_VOLT(LR_MUX10_USB_ID, 0)
690	VADC_CHAN_VOLT(AMUX_PU1, 0)
691	VADC_CHAN_VOLT(AMUX_PU2, 0)
692	VADC_CHAN_VOLT(LR_MUX3_BUF_XO_THERM, 0)
693
694	VADC_CHAN_VOLT(LR_MUX1_PU1_BAT_THERM, 0)
695	VADC_CHAN_VOLT(LR_MUX2_PU1_BAT_ID, 0)
696	VADC_CHAN_VOLT(LR_MUX3_PU1_XO_THERM, 0)
697	VADC_CHAN_VOLT(LR_MUX4_PU1_AMUX_THM1, 0)
698	VADC_CHAN_VOLT(LR_MUX5_PU1_AMUX_THM2, 0)
699	VADC_CHAN_VOLT(LR_MUX6_PU1_AMUX_THM3, 0)
700	VADC_CHAN_VOLT(LR_MUX7_PU1_AMUX_HW_ID, 0)
701	VADC_CHAN_VOLT(LR_MUX8_PU1_AMUX_THM4, 0)
702	VADC_CHAN_VOLT(LR_MUX9_PU1_AMUX_THM5, 0)
703	VADC_CHAN_VOLT(LR_MUX10_PU1_AMUX_USB_ID, 0)
704	VADC_CHAN_VOLT(LR_MUX3_BUF_PU1_XO_THERM, 0)
705
706	VADC_CHAN_VOLT(LR_MUX1_PU2_BAT_THERM, 0)
707	VADC_CHAN_VOLT(LR_MUX2_PU2_BAT_ID, 0)
708	VADC_CHAN_VOLT(LR_MUX3_PU2_XO_THERM, 0)
709	VADC_CHAN_VOLT(LR_MUX4_PU2_AMUX_THM1, 0)
710	VADC_CHAN_VOLT(LR_MUX5_PU2_AMUX_THM2, 0)
711	VADC_CHAN_VOLT(LR_MUX6_PU2_AMUX_THM3, 0)
712	VADC_CHAN_VOLT(LR_MUX7_PU2_AMUX_HW_ID, 0)
713	VADC_CHAN_VOLT(LR_MUX8_PU2_AMUX_THM4, 0)
714	VADC_CHAN_VOLT(LR_MUX9_PU2_AMUX_THM5, 0)
715	VADC_CHAN_VOLT(LR_MUX10_PU2_AMUX_USB_ID, 0)
716	VADC_CHAN_VOLT(LR_MUX3_BUF_PU2_XO_THERM, 0)
717
718	VADC_CHAN_VOLT(LR_MUX1_PU1_PU2_BAT_THERM, 0)
719	VADC_CHAN_VOLT(LR_MUX2_PU1_PU2_BAT_ID, 0)
720	VADC_CHAN_VOLT(LR_MUX3_PU1_PU2_XO_THERM, 0)
721	VADC_CHAN_VOLT(LR_MUX4_PU1_PU2_AMUX_THM1, 0)
722	VADC_CHAN_VOLT(LR_MUX5_PU1_PU2_AMUX_THM2, 0)
723	VADC_CHAN_VOLT(LR_MUX6_PU1_PU2_AMUX_THM3, 0)
724	VADC_CHAN_VOLT(LR_MUX7_PU1_PU2_AMUX_HW_ID, 0)
725	VADC_CHAN_VOLT(LR_MUX8_PU1_PU2_AMUX_THM4, 0)
726	VADC_CHAN_VOLT(LR_MUX9_PU1_PU2_AMUX_THM5, 0)
727	VADC_CHAN_VOLT(LR_MUX10_PU1_PU2_AMUX_USB_ID, 0)
728	VADC_CHAN_VOLT(LR_MUX3_BUF_PU1_PU2_XO_THERM, 0)
729};
730
731static int vadc_get_dt_channel_data(struct device *dev,
732				    struct vadc_channel_prop *prop,
733				    struct device_node *node)
734{
735	const char *name = node->name;
736	u32 chan, value, varr[2];
737	int ret;
738
739	ret = of_property_read_u32(node, "reg", &chan);
740	if (ret) {
741		dev_err(dev, "invalid channel number %s\n", name);
742		return ret;
743	}
744
745	if (chan > VADC_CHAN_MAX || chan < VADC_CHAN_MIN) {
746		dev_err(dev, "%s invalid channel number %d\n", name, chan);
747		return -EINVAL;
748	}
749
750	/* the channel has DT description */
751	prop->channel = chan;
752
753	ret = of_property_read_u32(node, "qcom,decimation", &value);
754	if (!ret) {
755		ret = vadc_decimation_from_dt(value);
756		if (ret < 0) {
757			dev_err(dev, "%02x invalid decimation %d\n",
758				chan, value);
759			return ret;
760		}
761		prop->decimation = ret;
762	} else {
763		prop->decimation = VADC_DEF_DECIMATION;
764	}
765
766	ret = of_property_read_u32_array(node, "qcom,pre-scaling", varr, 2);
767	if (!ret) {
768		ret = vadc_prescaling_from_dt(varr[0], varr[1]);
769		if (ret < 0) {
770			dev_err(dev, "%02x invalid pre-scaling <%d %d>\n",
771				chan, varr[0], varr[1]);
772			return ret;
773		}
774		prop->prescale = ret;
775	} else {
776		prop->prescale = vadc_chans[prop->channel].prescale_index;
777	}
778
779	ret = of_property_read_u32(node, "qcom,hw-settle-time", &value);
780	if (!ret) {
781		ret = vadc_hw_settle_time_from_dt(value);
782		if (ret < 0) {
783			dev_err(dev, "%02x invalid hw-settle-time %d us\n",
784				chan, value);
785			return ret;
786		}
787		prop->hw_settle_time = ret;
788	} else {
789		prop->hw_settle_time = VADC_DEF_HW_SETTLE_TIME;
790	}
791
792	ret = of_property_read_u32(node, "qcom,avg-samples", &value);
793	if (!ret) {
794		ret = vadc_avg_samples_from_dt(value);
795		if (ret < 0) {
796			dev_err(dev, "%02x invalid avg-samples %d\n",
797				chan, value);
798			return ret;
799		}
800		prop->avg_samples = ret;
801	} else {
802		prop->avg_samples = VADC_DEF_AVG_SAMPLES;
803	}
804
805	if (of_property_read_bool(node, "qcom,ratiometric"))
806		prop->calibration = VADC_CALIB_RATIOMETRIC;
807	else
808		prop->calibration = VADC_CALIB_ABSOLUTE;
809
810	dev_dbg(dev, "%02x name %s\n", chan, name);
811
812	return 0;
813}
814
815static int vadc_get_dt_data(struct vadc_priv *vadc, struct device_node *node)
816{
817	const struct vadc_channels *vadc_chan;
818	struct iio_chan_spec *iio_chan;
819	struct vadc_channel_prop prop;
820	struct device_node *child;
821	unsigned int index = 0;
822	int ret;
823
824	vadc->nchannels = of_get_available_child_count(node);
825	if (!vadc->nchannels)
826		return -EINVAL;
827
828	vadc->iio_chans = devm_kcalloc(vadc->dev, vadc->nchannels,
829				       sizeof(*vadc->iio_chans), GFP_KERNEL);
830	if (!vadc->iio_chans)
831		return -ENOMEM;
832
833	vadc->chan_props = devm_kcalloc(vadc->dev, vadc->nchannels,
834					sizeof(*vadc->chan_props), GFP_KERNEL);
835	if (!vadc->chan_props)
836		return -ENOMEM;
837
838	iio_chan = vadc->iio_chans;
839
840	for_each_available_child_of_node(node, child) {
841		ret = vadc_get_dt_channel_data(vadc->dev, &prop, child);
842		if (ret) {
843			of_node_put(child);
844			return ret;
845		}
846
847		vadc->chan_props[index] = prop;
848
849		vadc_chan = &vadc_chans[prop.channel];
850
851		iio_chan->channel = prop.channel;
852		iio_chan->datasheet_name = vadc_chan->datasheet_name;
853		iio_chan->info_mask_separate = vadc_chan->info_mask;
854		iio_chan->type = vadc_chan->type;
855		iio_chan->indexed = 1;
856		iio_chan->address = index++;
857
858		iio_chan++;
859	}
860
861	/* These channels are mandatory, they are used as reference points */
862	if (!vadc_get_channel(vadc, VADC_REF_1250MV)) {
863		dev_err(vadc->dev, "Please define 1.25V channel\n");
864		return -ENODEV;
865	}
866
867	if (!vadc_get_channel(vadc, VADC_REF_625MV)) {
868		dev_err(vadc->dev, "Please define 0.625V channel\n");
869		return -ENODEV;
870	}
871
872	if (!vadc_get_channel(vadc, VADC_VDD_VADC)) {
873		dev_err(vadc->dev, "Please define VDD channel\n");
874		return -ENODEV;
875	}
876
877	if (!vadc_get_channel(vadc, VADC_GND_REF)) {
878		dev_err(vadc->dev, "Please define GND channel\n");
879		return -ENODEV;
880	}
881
882	return 0;
883}
884
885static irqreturn_t vadc_isr(int irq, void *dev_id)
886{
887	struct vadc_priv *vadc = dev_id;
888
889	complete(&vadc->complete);
890
891	return IRQ_HANDLED;
892}
893
894static int vadc_check_revision(struct vadc_priv *vadc)
895{
896	u8 val;
897	int ret;
898
899	ret = vadc_read(vadc, VADC_PERPH_TYPE, &val);
900	if (ret)
901		return ret;
902
903	if (val < VADC_PERPH_TYPE_ADC) {
904		dev_err(vadc->dev, "%d is not ADC\n", val);
905		return -ENODEV;
906	}
907
908	ret = vadc_read(vadc, VADC_PERPH_SUBTYPE, &val);
909	if (ret)
910		return ret;
911
912	if (val < VADC_PERPH_SUBTYPE_VADC) {
913		dev_err(vadc->dev, "%d is not VADC\n", val);
914		return -ENODEV;
915	}
916
917	ret = vadc_read(vadc, VADC_REVISION2, &val);
918	if (ret)
919		return ret;
920
921	if (val < VADC_REVISION2_SUPPORTED_VADC) {
922		dev_err(vadc->dev, "revision %d not supported\n", val);
923		return -ENODEV;
924	}
925
926	return 0;
927}
928
929static int vadc_probe(struct platform_device *pdev)
930{
931	struct device_node *node = pdev->dev.of_node;
932	struct device *dev = &pdev->dev;
933	struct iio_dev *indio_dev;
934	struct vadc_priv *vadc;
935	struct regmap *regmap;
936	int ret, irq_eoc;
937	u32 reg;
938
939	regmap = dev_get_regmap(dev->parent, NULL);
940	if (!regmap)
941		return -ENODEV;
942
943	ret = of_property_read_u32(node, "reg", &reg);
944	if (ret < 0)
945		return ret;
946
947	indio_dev = devm_iio_device_alloc(dev, sizeof(*vadc));
948	if (!indio_dev)
949		return -ENOMEM;
950
951	vadc = iio_priv(indio_dev);
952	vadc->regmap = regmap;
953	vadc->dev = dev;
954	vadc->base = reg;
955	vadc->are_ref_measured = false;
956	init_completion(&vadc->complete);
957	mutex_init(&vadc->lock);
958
959	ret = vadc_check_revision(vadc);
960	if (ret)
961		return ret;
962
963	ret = vadc_get_dt_data(vadc, node);
964	if (ret)
965		return ret;
966
967	irq_eoc = platform_get_irq(pdev, 0);
968	if (irq_eoc < 0) {
969		if (irq_eoc == -EPROBE_DEFER || irq_eoc == -EINVAL)
970			return irq_eoc;
971		vadc->poll_eoc = true;
972	} else {
973		ret = devm_request_irq(dev, irq_eoc, vadc_isr, 0,
974				       "spmi-vadc", vadc);
975		if (ret)
976			return ret;
977	}
978
979	ret = vadc_reset(vadc);
980	if (ret) {
981		dev_err(dev, "reset failed\n");
982		return ret;
983	}
984
985	ret = vadc_measure_ref_points(vadc);
986	if (ret)
987		return ret;
988
989	indio_dev->dev.parent = dev;
990	indio_dev->dev.of_node = node;
991	indio_dev->name = pdev->name;
992	indio_dev->modes = INDIO_DIRECT_MODE;
993	indio_dev->info = &vadc_info;
994	indio_dev->channels = vadc->iio_chans;
995	indio_dev->num_channels = vadc->nchannels;
996
997	return devm_iio_device_register(dev, indio_dev);
998}
999
1000static const struct of_device_id vadc_match_table[] = {
1001	{ .compatible = "qcom,spmi-vadc" },
1002	{ }
1003};
1004MODULE_DEVICE_TABLE(of, vadc_match_table);
1005
1006static struct platform_driver vadc_driver = {
1007	.driver = {
1008		   .name = "qcom-spmi-vadc",
1009		   .of_match_table = vadc_match_table,
1010	},
1011	.probe = vadc_probe,
1012};
1013module_platform_driver(vadc_driver);
1014
1015MODULE_ALIAS("platform:qcom-spmi-vadc");
1016MODULE_DESCRIPTION("Qualcomm SPMI PMIC voltage ADC driver");
1017MODULE_LICENSE("GPL v2");
1018MODULE_AUTHOR("Stanimir Varbanov <svarbanov@mm-sol.com>");
1019MODULE_AUTHOR("Ivan T. Ivanov <iivanov@mm-sol.com>");
1020