1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * palmas-adc.c -- TI PALMAS GPADC.
4 *
5 * Copyright (c) 2013, NVIDIA Corporation. All rights reserved.
6 *
7 * Author: Pradeep Goudagunta <pgoudagunta@nvidia.com>
8 */
9
10#include <linux/module.h>
11#include <linux/err.h>
12#include <linux/irq.h>
13#include <linux/interrupt.h>
14#include <linux/platform_device.h>
15#include <linux/slab.h>
16#include <linux/delay.h>
17#include <linux/pm.h>
18#include <linux/mfd/palmas.h>
19#include <linux/completion.h>
20#include <linux/of.h>
21#include <linux/iio/events.h>
22#include <linux/iio/iio.h>
23#include <linux/iio/machine.h>
24#include <linux/iio/driver.h>
25
26#define MOD_NAME "palmas-gpadc"
27#define PALMAS_ADC_CONVERSION_TIMEOUT	(msecs_to_jiffies(5000))
28#define PALMAS_TO_BE_CALCULATED 0
29#define PALMAS_GPADC_TRIMINVALID	-1
30
31struct palmas_gpadc_info {
32/* calibration codes and regs */
33	int x1;	/* lower ideal code */
34	int x2;	/* higher ideal code */
35	int v1;	/* expected lower volt reading */
36	int v2;	/* expected higher volt reading */
37	u8 trim1_reg;	/* register number for lower trim */
38	u8 trim2_reg;	/* register number for upper trim */
39	int gain;	/* calculated from above (after reading trim regs) */
40	int offset;	/* calculated from above (after reading trim regs) */
41	int gain_error;	/* calculated from above (after reading trim regs) */
42	bool is_uncalibrated;	/* if channel has calibration data */
43};
44
45#define PALMAS_ADC_INFO(_chan, _x1, _x2, _v1, _v2, _t1, _t2, _is_uncalibrated) \
46	[PALMAS_ADC_CH_##_chan] = { \
47		.x1 = _x1, \
48		.x2 = _x2, \
49		.v1 = _v1, \
50		.v2 = _v2, \
51		.gain = PALMAS_TO_BE_CALCULATED, \
52		.offset = PALMAS_TO_BE_CALCULATED, \
53		.gain_error = PALMAS_TO_BE_CALCULATED, \
54		.trim1_reg = PALMAS_GPADC_TRIM##_t1, \
55		.trim2_reg = PALMAS_GPADC_TRIM##_t2,  \
56		.is_uncalibrated = _is_uncalibrated \
57	}
58
59static struct palmas_gpadc_info palmas_gpadc_info[] = {
60	PALMAS_ADC_INFO(IN0, 2064, 3112, 630, 950, 1, 2, false),
61	PALMAS_ADC_INFO(IN1, 2064, 3112, 630, 950, 1, 2, false),
62	PALMAS_ADC_INFO(IN2, 2064, 3112, 1260, 1900, 3, 4, false),
63	PALMAS_ADC_INFO(IN3, 2064, 3112, 630, 950, 1, 2, false),
64	PALMAS_ADC_INFO(IN4, 2064, 3112, 630, 950, 1, 2, false),
65	PALMAS_ADC_INFO(IN5, 2064, 3112, 630, 950, 1, 2, false),
66	PALMAS_ADC_INFO(IN6, 2064, 3112, 2520, 3800, 5, 6, false),
67	PALMAS_ADC_INFO(IN7, 2064, 3112, 2520, 3800, 7, 8, false),
68	PALMAS_ADC_INFO(IN8, 2064, 3112, 3150, 4750, 9, 10, false),
69	PALMAS_ADC_INFO(IN9, 2064, 3112, 5670, 8550, 11, 12, false),
70	PALMAS_ADC_INFO(IN10, 2064, 3112, 3465, 5225, 13, 14, false),
71	PALMAS_ADC_INFO(IN11, 0, 0, 0, 0, INVALID, INVALID, true),
72	PALMAS_ADC_INFO(IN12, 0, 0, 0, 0, INVALID, INVALID, true),
73	PALMAS_ADC_INFO(IN13, 0, 0, 0, 0, INVALID, INVALID, true),
74	PALMAS_ADC_INFO(IN14, 2064, 3112, 3645, 5225, 15, 16, false),
75	PALMAS_ADC_INFO(IN15, 0, 0, 0, 0, INVALID, INVALID, true),
76};
77
78struct palmas_adc_event {
79	bool enabled;
80	int channel;
81	enum iio_event_direction direction;
82};
83
84struct palmas_gpadc_thresholds {
85	int high;
86	int low;
87};
88
89/*
90 * struct palmas_gpadc - the palmas_gpadc structure
91 * @ch0_current:	channel 0 current source setting
92 *			0: 0 uA
93 *			1: 5 uA
94 *			2: 15 uA
95 *			3: 20 uA
96 * @ch3_current:	channel 0 current source setting
97 *			0: 0 uA
98 *			1: 10 uA
99 *			2: 400 uA
100 *			3: 800 uA
101 * @extended_delay:	enable the gpadc extended delay mode
102 * @auto_conversion_period:	define the auto_conversion_period
103 * @lock:	Lock to protect the device state during a potential concurrent
104 *		read access from userspace. Reading a raw value requires a sequence
105 *		of register writes, then a wait for a completion callback,
106 *		and finally a register read, during which userspace could issue
107 *		another read request. This lock protects a read access from
108 *		ocurring before another one has finished.
109 *
110 * This is the palmas_gpadc structure to store run-time information
111 * and pointers for this driver instance.
112 */
113struct palmas_gpadc {
114	struct device			*dev;
115	struct palmas			*palmas;
116	u8				ch0_current;
117	u8				ch3_current;
118	bool				extended_delay;
119	int				irq;
120	int				irq_auto_0;
121	int				irq_auto_1;
122	struct palmas_gpadc_info	*adc_info;
123	struct completion		conv_completion;
124	struct palmas_adc_event		event0;
125	struct palmas_adc_event		event1;
126	struct palmas_gpadc_thresholds	thresholds[PALMAS_ADC_CH_MAX];
127	int				auto_conversion_period;
128	struct mutex			lock;
129};
130
131static struct palmas_adc_event *palmas_gpadc_get_event(struct palmas_gpadc *adc,
132						       int adc_chan,
133						       enum iio_event_direction dir)
134{
135	if (adc_chan == adc->event0.channel && dir == adc->event0.direction)
136		return &adc->event0;
137
138	if (adc_chan == adc->event1.channel && dir == adc->event1.direction)
139		return &adc->event1;
140
141	return NULL;
142}
143
144static bool palmas_gpadc_channel_is_freerunning(struct palmas_gpadc *adc,
145						int adc_chan)
146{
147	return palmas_gpadc_get_event(adc, adc_chan, IIO_EV_DIR_RISING) ||
148		palmas_gpadc_get_event(adc, adc_chan, IIO_EV_DIR_FALLING);
149}
150
151/*
152 * GPADC lock issue in AUTO mode.
153 * Impact: In AUTO mode, GPADC conversion can be locked after disabling AUTO
154 *	   mode feature.
155 * Details:
156 *	When the AUTO mode is the only conversion mode enabled, if the AUTO
157 *	mode feature is disabled with bit GPADC_AUTO_CTRL.  AUTO_CONV1_EN = 0
158 *	or bit GPADC_AUTO_CTRL.  AUTO_CONV0_EN = 0 during a conversion, the
159 *	conversion mechanism can be seen as locked meaning that all following
160 *	conversion will give 0 as a result.  Bit GPADC_STATUS.GPADC_AVAILABLE
161 *	will stay at 0 meaning that GPADC is busy.  An RT conversion can unlock
162 *	the GPADC.
163 *
164 * Workaround(s):
165 *	To avoid the lock mechanism, the workaround to follow before any stop
166 *	conversion request is:
167 *	Force the GPADC state machine to be ON by using the GPADC_CTRL1.
168 *		GPADC_FORCE bit = 1
169 *	Shutdown the GPADC AUTO conversion using
170 *		GPADC_AUTO_CTRL.SHUTDOWN_CONV[01] = 0.
171 *	After 100us, force the GPADC state machine to be OFF by using the
172 *		GPADC_CTRL1.  GPADC_FORCE bit = 0
173 */
174
175static int palmas_disable_auto_conversion(struct palmas_gpadc *adc)
176{
177	int ret;
178
179	ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
180			PALMAS_GPADC_CTRL1,
181			PALMAS_GPADC_CTRL1_GPADC_FORCE,
182			PALMAS_GPADC_CTRL1_GPADC_FORCE);
183	if (ret < 0) {
184		dev_err(adc->dev, "GPADC_CTRL1 update failed: %d\n", ret);
185		return ret;
186	}
187
188	ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
189			PALMAS_GPADC_AUTO_CTRL,
190			PALMAS_GPADC_AUTO_CTRL_SHUTDOWN_CONV1 |
191			PALMAS_GPADC_AUTO_CTRL_SHUTDOWN_CONV0,
192			0);
193	if (ret < 0) {
194		dev_err(adc->dev, "AUTO_CTRL update failed: %d\n", ret);
195		return ret;
196	}
197
198	udelay(100);
199
200	ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
201			PALMAS_GPADC_CTRL1,
202			PALMAS_GPADC_CTRL1_GPADC_FORCE, 0);
203	if (ret < 0)
204		dev_err(adc->dev, "GPADC_CTRL1 update failed: %d\n", ret);
205
206	return ret;
207}
208
209static irqreturn_t palmas_gpadc_irq(int irq, void *data)
210{
211	struct palmas_gpadc *adc = data;
212
213	complete(&adc->conv_completion);
214
215	return IRQ_HANDLED;
216}
217
218static irqreturn_t palmas_gpadc_irq_auto(int irq, void *data)
219{
220	struct iio_dev *indio_dev = data;
221	struct palmas_gpadc *adc = iio_priv(indio_dev);
222	struct palmas_adc_event *ev;
223
224	dev_dbg(adc->dev, "Threshold interrupt %d occurs\n", irq);
225	palmas_disable_auto_conversion(adc);
226
227	ev = (irq == adc->irq_auto_0) ? &adc->event0 : &adc->event1;
228	if (ev->channel != -1) {
229		enum iio_event_direction dir;
230		u64 code;
231
232		dir = ev->direction;
233		code = IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, ev->channel,
234					    IIO_EV_TYPE_THRESH, dir);
235		iio_push_event(indio_dev, code, iio_get_time_ns(indio_dev));
236	}
237
238	return IRQ_HANDLED;
239}
240
241static int palmas_gpadc_start_mask_interrupt(struct palmas_gpadc *adc,
242						bool mask)
243{
244	int ret;
245
246	if (!mask)
247		ret = palmas_update_bits(adc->palmas, PALMAS_INTERRUPT_BASE,
248					PALMAS_INT3_MASK,
249					PALMAS_INT3_MASK_GPADC_EOC_SW, 0);
250	else
251		ret = palmas_update_bits(adc->palmas, PALMAS_INTERRUPT_BASE,
252					PALMAS_INT3_MASK,
253					PALMAS_INT3_MASK_GPADC_EOC_SW,
254					PALMAS_INT3_MASK_GPADC_EOC_SW);
255	if (ret < 0)
256		dev_err(adc->dev, "GPADC INT MASK update failed: %d\n", ret);
257
258	return ret;
259}
260
261static int palmas_gpadc_enable(struct palmas_gpadc *adc, int adc_chan,
262			       int enable)
263{
264	unsigned int mask, val;
265	int ret;
266
267	if (enable) {
268		val = (adc->extended_delay
269			<< PALMAS_GPADC_RT_CTRL_EXTEND_DELAY_SHIFT);
270		ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
271					PALMAS_GPADC_RT_CTRL,
272					PALMAS_GPADC_RT_CTRL_EXTEND_DELAY, val);
273		if (ret < 0) {
274			dev_err(adc->dev, "RT_CTRL update failed: %d\n", ret);
275			return ret;
276		}
277
278		mask = (PALMAS_GPADC_CTRL1_CURRENT_SRC_CH0_MASK |
279			PALMAS_GPADC_CTRL1_CURRENT_SRC_CH3_MASK |
280			PALMAS_GPADC_CTRL1_GPADC_FORCE);
281		val = (adc->ch0_current
282			<< PALMAS_GPADC_CTRL1_CURRENT_SRC_CH0_SHIFT);
283		val |= (adc->ch3_current
284			<< PALMAS_GPADC_CTRL1_CURRENT_SRC_CH3_SHIFT);
285		val |= PALMAS_GPADC_CTRL1_GPADC_FORCE;
286		ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
287				PALMAS_GPADC_CTRL1, mask, val);
288		if (ret < 0) {
289			dev_err(adc->dev,
290				"Failed to update current setting: %d\n", ret);
291			return ret;
292		}
293
294		mask = (PALMAS_GPADC_SW_SELECT_SW_CONV0_SEL_MASK |
295			PALMAS_GPADC_SW_SELECT_SW_CONV_EN);
296		val = (adc_chan | PALMAS_GPADC_SW_SELECT_SW_CONV_EN);
297		ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
298				PALMAS_GPADC_SW_SELECT, mask, val);
299		if (ret < 0) {
300			dev_err(adc->dev, "SW_SELECT update failed: %d\n", ret);
301			return ret;
302		}
303	} else {
304		ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
305				PALMAS_GPADC_SW_SELECT, 0);
306		if (ret < 0)
307			dev_err(adc->dev, "SW_SELECT write failed: %d\n", ret);
308
309		ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
310				PALMAS_GPADC_CTRL1,
311				PALMAS_GPADC_CTRL1_GPADC_FORCE, 0);
312		if (ret < 0) {
313			dev_err(adc->dev, "CTRL1 update failed: %d\n", ret);
314			return ret;
315		}
316	}
317
318	return ret;
319}
320
321static int palmas_gpadc_read_prepare(struct palmas_gpadc *adc, int adc_chan)
322{
323	int ret;
324
325	if (palmas_gpadc_channel_is_freerunning(adc, adc_chan))
326		return 0; /* ADC already running */
327
328	ret = palmas_gpadc_enable(adc, adc_chan, true);
329	if (ret < 0)
330		return ret;
331
332	return palmas_gpadc_start_mask_interrupt(adc, 0);
333}
334
335static void palmas_gpadc_read_done(struct palmas_gpadc *adc, int adc_chan)
336{
337	palmas_gpadc_start_mask_interrupt(adc, 1);
338	palmas_gpadc_enable(adc, adc_chan, false);
339}
340
341static int palmas_gpadc_calibrate(struct palmas_gpadc *adc, int adc_chan)
342{
343	int k;
344	int d1;
345	int d2;
346	int ret;
347	int gain;
348	int x1 =  adc->adc_info[adc_chan].x1;
349	int x2 =  adc->adc_info[adc_chan].x2;
350	int v1 = adc->adc_info[adc_chan].v1;
351	int v2 = adc->adc_info[adc_chan].v2;
352
353	ret = palmas_read(adc->palmas, PALMAS_TRIM_GPADC_BASE,
354				adc->adc_info[adc_chan].trim1_reg, &d1);
355	if (ret < 0) {
356		dev_err(adc->dev, "TRIM read failed: %d\n", ret);
357		goto scrub;
358	}
359
360	ret = palmas_read(adc->palmas, PALMAS_TRIM_GPADC_BASE,
361				adc->adc_info[adc_chan].trim2_reg, &d2);
362	if (ret < 0) {
363		dev_err(adc->dev, "TRIM read failed: %d\n", ret);
364		goto scrub;
365	}
366
367	/* gain error calculation */
368	k = (1000 + (1000 * (d2 - d1)) / (x2 - x1));
369
370	/* gain calculation */
371	gain = ((v2 - v1) * 1000) / (x2 - x1);
372
373	adc->adc_info[adc_chan].gain_error = k;
374	adc->adc_info[adc_chan].gain = gain;
375	/* offset Calculation */
376	adc->adc_info[adc_chan].offset = (d1 * 1000) - ((k - 1000) * x1);
377
378scrub:
379	return ret;
380}
381
382static int palmas_gpadc_start_conversion(struct palmas_gpadc *adc, int adc_chan)
383{
384	unsigned int val;
385	int ret;
386
387	if (palmas_gpadc_channel_is_freerunning(adc, adc_chan)) {
388		int event = (adc_chan == adc->event0.channel) ? 0 : 1;
389		unsigned int reg = (event == 0) ?
390			PALMAS_GPADC_AUTO_CONV0_LSB :
391			PALMAS_GPADC_AUTO_CONV1_LSB;
392
393		ret = palmas_bulk_read(adc->palmas, PALMAS_GPADC_BASE,
394					reg, &val, 2);
395		if (ret < 0) {
396			dev_err(adc->dev, "AUTO_CONV%x_LSB read failed: %d\n",
397				event, ret);
398			return ret;
399		}
400	} else {
401		init_completion(&adc->conv_completion);
402		ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
403					PALMAS_GPADC_SW_SELECT,
404					PALMAS_GPADC_SW_SELECT_SW_START_CONV0,
405					PALMAS_GPADC_SW_SELECT_SW_START_CONV0);
406		if (ret < 0) {
407			dev_err(adc->dev, "SELECT_SW_START write failed: %d\n", ret);
408			return ret;
409		}
410
411		ret = wait_for_completion_timeout(&adc->conv_completion,
412					PALMAS_ADC_CONVERSION_TIMEOUT);
413		if (ret == 0) {
414			dev_err(adc->dev, "conversion not completed\n");
415			return -ETIMEDOUT;
416		}
417
418		ret = palmas_bulk_read(adc->palmas, PALMAS_GPADC_BASE,
419					PALMAS_GPADC_SW_CONV0_LSB, &val, 2);
420		if (ret < 0) {
421			dev_err(adc->dev, "SW_CONV0_LSB read failed: %d\n", ret);
422			return ret;
423		}
424	}
425
426	ret = val & 0xFFF;
427
428	return ret;
429}
430
431static int palmas_gpadc_get_calibrated_code(struct palmas_gpadc *adc,
432						int adc_chan, int val)
433{
434	if (!adc->adc_info[adc_chan].is_uncalibrated)
435		val  = (val*1000 - adc->adc_info[adc_chan].offset) /
436					adc->adc_info[adc_chan].gain_error;
437
438	if (val < 0) {
439		if (val < -10)
440			dev_err(adc->dev, "Mismatch with calibration var = %d\n", val);
441		return 0;
442	}
443
444	val = (val * adc->adc_info[adc_chan].gain) / 1000;
445
446	return val;
447}
448
449/*
450 * The high and low threshold values are calculated based on the advice given
451 * in TI Application Report SLIA087A, "Guide to Using the GPADC in PS65903x,
452 * TPS65917-Q1, TPS65919-Q1, and TPS65916 Devices". This document recommend
453 * taking ADC tolerances into account and is based on the device integral non-
454 * linearity (INL), offset error and gain error:
455 *
456 *   raw high threshold = (ideal threshold + INL) * gain error + offset error
457 *
458 * The gain error include both gain error, as specified in the datasheet, and
459 * the gain error drift. These paramenters vary depending on device and whether
460 * the channel is calibrated (trimmed) or not.
461 */
462static int palmas_gpadc_threshold_with_tolerance(int val, const int INL,
463						 const int gain_error,
464						 const int offset_error)
465{
466	val = ((val + INL) * (1000 + gain_error)) / 1000 + offset_error;
467
468	return clamp(val, 0, 0xFFF);
469}
470
471/*
472 * The values below are taken from the datasheet of TWL6035, TWL6037.
473 * todo: get max INL, gain error, and offset error from OF.
474 */
475static int palmas_gpadc_get_high_threshold_raw(struct palmas_gpadc *adc,
476					       struct palmas_adc_event *ev)
477{
478	const int adc_chan = ev->channel;
479	int val = adc->thresholds[adc_chan].high;
480	/* integral nonlinearity, measured in LSB */
481	const int max_INL = 2;
482	/* measured in LSB */
483	int max_offset_error;
484	/* 0.2% when calibrated */
485	int max_gain_error = 2;
486
487	val = (val * 1000) / adc->adc_info[adc_chan].gain;
488
489	if (adc->adc_info[adc_chan].is_uncalibrated) {
490		/* 2% worse */
491		max_gain_error += 20;
492		max_offset_error = 36;
493	} else {
494		val = (val * adc->adc_info[adc_chan].gain_error +
495		       adc->adc_info[adc_chan].offset) /
496			1000;
497		max_offset_error = 2;
498	}
499
500	return palmas_gpadc_threshold_with_tolerance(val,
501						     max_INL,
502						     max_gain_error,
503						     max_offset_error);
504}
505
506/*
507 * The values below are taken from the datasheet of TWL6035, TWL6037.
508 * todo: get min INL, gain error, and offset error from OF.
509 */
510static int palmas_gpadc_get_low_threshold_raw(struct palmas_gpadc *adc,
511					      struct palmas_adc_event *ev)
512{
513	const int adc_chan = ev->channel;
514	int val = adc->thresholds[adc_chan].low;
515	/* integral nonlinearity, measured in LSB */
516	const int min_INL = -2;
517	/* measured in LSB */
518	int min_offset_error;
519	/* -0.6% when calibrated */
520	int min_gain_error = -6;
521
522	val = (val * 1000) / adc->adc_info[adc_chan].gain;
523
524        if (adc->adc_info[adc_chan].is_uncalibrated) {
525		/* 2% worse */
526		min_gain_error -= 20;
527		min_offset_error = -36;
528        } else {
529		val = (val * adc->adc_info[adc_chan].gain_error -
530		       adc->adc_info[adc_chan].offset) /
531			1000;
532		min_offset_error = -2;
533        }
534
535	return palmas_gpadc_threshold_with_tolerance(val,
536						     min_INL,
537						     min_gain_error,
538						     min_offset_error);
539}
540
541static int palmas_gpadc_read_raw(struct iio_dev *indio_dev,
542	struct iio_chan_spec const *chan, int *val, int *val2, long mask)
543{
544	struct  palmas_gpadc *adc = iio_priv(indio_dev);
545	int adc_chan = chan->channel;
546	int ret = 0;
547
548	if (adc_chan >= PALMAS_ADC_CH_MAX)
549		return -EINVAL;
550
551	mutex_lock(&adc->lock);
552
553	switch (mask) {
554	case IIO_CHAN_INFO_RAW:
555	case IIO_CHAN_INFO_PROCESSED:
556		ret = palmas_gpadc_read_prepare(adc, adc_chan);
557		if (ret < 0)
558			goto out;
559
560		ret = palmas_gpadc_start_conversion(adc, adc_chan);
561		if (ret < 0) {
562			dev_err(adc->dev,
563			"ADC start conversion failed\n");
564			goto out;
565		}
566
567		if (mask == IIO_CHAN_INFO_PROCESSED)
568			ret = palmas_gpadc_get_calibrated_code(
569							adc, adc_chan, ret);
570
571		*val = ret;
572
573		ret = IIO_VAL_INT;
574		goto out;
575	}
576
577	mutex_unlock(&adc->lock);
578	return ret;
579
580out:
581	palmas_gpadc_read_done(adc, adc_chan);
582	mutex_unlock(&adc->lock);
583
584	return ret;
585}
586
587static int palmas_gpadc_read_event_config(struct iio_dev *indio_dev,
588					  const struct iio_chan_spec *chan,
589					  enum iio_event_type type,
590					  enum iio_event_direction dir)
591{
592	struct palmas_gpadc *adc = iio_priv(indio_dev);
593	int adc_chan = chan->channel;
594	int ret = 0;
595
596	if (adc_chan >= PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)
597		return -EINVAL;
598
599	mutex_lock(&adc->lock);
600
601	if (palmas_gpadc_get_event(adc, adc_chan, dir))
602		ret = 1;
603
604	mutex_unlock(&adc->lock);
605
606	return ret;
607}
608
609static int palmas_adc_configure_events(struct palmas_gpadc *adc);
610static int palmas_adc_reset_events(struct palmas_gpadc *adc);
611
612static int palmas_gpadc_reconfigure_event_channels(struct palmas_gpadc *adc)
613{
614	return (adc->event0.enabled || adc->event1.enabled) ?
615		palmas_adc_configure_events(adc) :
616		palmas_adc_reset_events(adc);
617}
618
619static int palmas_gpadc_enable_event_config(struct palmas_gpadc *adc,
620					    const struct iio_chan_spec *chan,
621					    enum iio_event_direction dir)
622{
623	struct palmas_adc_event *ev;
624	int adc_chan = chan->channel;
625
626	if (palmas_gpadc_get_event(adc, adc_chan, dir))
627		/* already enabled */
628		return 0;
629
630	if (adc->event0.channel == -1) {
631		ev = &adc->event0;
632	} else if (adc->event1.channel == -1) {
633		/* event0 has to be the lowest channel */
634		if (adc_chan < adc->event0.channel) {
635			adc->event1 = adc->event0;
636			ev = &adc->event0;
637		} else {
638			ev = &adc->event1;
639		}
640	} else { /* both AUTO channels already in use */
641		dev_warn(adc->dev, "event0 - %d, event1 - %d\n",
642			 adc->event0.channel, adc->event1.channel);
643		return -EBUSY;
644	}
645
646	ev->enabled = true;
647	ev->channel = adc_chan;
648	ev->direction = dir;
649
650	return palmas_gpadc_reconfigure_event_channels(adc);
651}
652
653static int palmas_gpadc_disable_event_config(struct palmas_gpadc *adc,
654					     const struct iio_chan_spec *chan,
655					     enum iio_event_direction dir)
656{
657	int adc_chan = chan->channel;
658	struct palmas_adc_event *ev = palmas_gpadc_get_event(adc, adc_chan, dir);
659
660	if (!ev)
661		return 0;
662
663	if (ev == &adc->event0) {
664		adc->event0 = adc->event1;
665		ev = &adc->event1;
666	}
667
668	ev->enabled = false;
669	ev->channel = -1;
670	ev->direction = IIO_EV_DIR_NONE;
671
672	return palmas_gpadc_reconfigure_event_channels(adc);
673}
674
675static int palmas_gpadc_write_event_config(struct iio_dev *indio_dev,
676					   const struct iio_chan_spec *chan,
677					   enum iio_event_type type,
678					   enum iio_event_direction dir,
679					   int state)
680{
681	struct palmas_gpadc *adc = iio_priv(indio_dev);
682	int adc_chan = chan->channel;
683	int ret;
684
685	if (adc_chan >= PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)
686		return -EINVAL;
687
688	mutex_lock(&adc->lock);
689
690	if (state)
691		ret = palmas_gpadc_enable_event_config(adc, chan, dir);
692	else
693		ret = palmas_gpadc_disable_event_config(adc, chan, dir);
694
695	mutex_unlock(&adc->lock);
696
697	return ret;
698}
699
700static int palmas_gpadc_read_event_value(struct iio_dev *indio_dev,
701					 const struct iio_chan_spec *chan,
702					 enum iio_event_type type,
703					 enum iio_event_direction dir,
704					 enum iio_event_info info,
705					 int *val, int *val2)
706{
707	struct palmas_gpadc *adc = iio_priv(indio_dev);
708	int adc_chan = chan->channel;
709	int ret;
710
711	if (adc_chan >= PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)
712		return -EINVAL;
713
714	mutex_lock(&adc->lock);
715
716	switch (info) {
717	case IIO_EV_INFO_VALUE:
718		*val = (dir == IIO_EV_DIR_RISING) ?
719			adc->thresholds[adc_chan].high :
720			adc->thresholds[adc_chan].low;
721		ret = IIO_VAL_INT;
722		break;
723	default:
724		ret = -EINVAL;
725		break;
726	}
727
728	mutex_unlock(&adc->lock);
729
730	return ret;
731}
732
733static int palmas_gpadc_write_event_value(struct iio_dev *indio_dev,
734					  const struct iio_chan_spec *chan,
735					  enum iio_event_type type,
736					  enum iio_event_direction dir,
737					  enum iio_event_info info,
738					  int val, int val2)
739{
740	struct palmas_gpadc *adc = iio_priv(indio_dev);
741	int adc_chan = chan->channel;
742	int old;
743	int ret;
744
745	if (adc_chan >= PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)
746		return -EINVAL;
747
748	mutex_lock(&adc->lock);
749	switch (info) {
750	case IIO_EV_INFO_VALUE:
751		if (val < 0 || val > 0xFFF) {
752			ret = -EINVAL;
753			goto out_unlock;
754		}
755		if (dir == IIO_EV_DIR_RISING) {
756			old = adc->thresholds[adc_chan].high;
757			adc->thresholds[adc_chan].high = val;
758		} else {
759			old = adc->thresholds[adc_chan].low;
760			adc->thresholds[adc_chan].low = val;
761		}
762		ret = 0;
763		break;
764	default:
765		ret = -EINVAL;
766		goto out_unlock;
767	}
768
769	if (val != old && palmas_gpadc_get_event(adc, adc_chan, dir))
770		ret = palmas_gpadc_reconfigure_event_channels(adc);
771
772out_unlock:
773	mutex_unlock(&adc->lock);
774
775	return ret;
776}
777
778static const struct iio_info palmas_gpadc_iio_info = {
779	.read_raw = palmas_gpadc_read_raw,
780	.read_event_config = palmas_gpadc_read_event_config,
781	.write_event_config = palmas_gpadc_write_event_config,
782	.read_event_value = palmas_gpadc_read_event_value,
783	.write_event_value = palmas_gpadc_write_event_value,
784};
785
786static const struct iio_event_spec palmas_gpadc_events[] = {
787	{
788		.type = IIO_EV_TYPE_THRESH,
789		.dir = IIO_EV_DIR_RISING,
790		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
791				BIT(IIO_EV_INFO_ENABLE),
792	}, {
793		.type = IIO_EV_TYPE_THRESH,
794		.dir = IIO_EV_DIR_FALLING,
795		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
796				BIT(IIO_EV_INFO_ENABLE),
797	},
798};
799
800#define PALMAS_ADC_CHAN_IIO(chan, _type, chan_info)	\
801{							\
802	.datasheet_name = PALMAS_DATASHEET_NAME(chan),	\
803	.type = _type,					\
804	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |	\
805			BIT(chan_info),			\
806	.indexed = 1,					\
807	.channel = PALMAS_ADC_CH_##chan,		\
808	.event_spec = palmas_gpadc_events,		\
809	.num_event_specs = ARRAY_SIZE(palmas_gpadc_events)	\
810}
811
812static const struct iio_chan_spec palmas_gpadc_iio_channel[] = {
813	PALMAS_ADC_CHAN_IIO(IN0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
814	PALMAS_ADC_CHAN_IIO(IN1, IIO_TEMP, IIO_CHAN_INFO_RAW),
815	PALMAS_ADC_CHAN_IIO(IN2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
816	PALMAS_ADC_CHAN_IIO(IN3, IIO_TEMP, IIO_CHAN_INFO_RAW),
817	PALMAS_ADC_CHAN_IIO(IN4, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
818	PALMAS_ADC_CHAN_IIO(IN5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
819	PALMAS_ADC_CHAN_IIO(IN6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
820	PALMAS_ADC_CHAN_IIO(IN7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
821	PALMAS_ADC_CHAN_IIO(IN8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
822	PALMAS_ADC_CHAN_IIO(IN9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
823	PALMAS_ADC_CHAN_IIO(IN10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
824	PALMAS_ADC_CHAN_IIO(IN11, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
825	PALMAS_ADC_CHAN_IIO(IN12, IIO_TEMP, IIO_CHAN_INFO_RAW),
826	PALMAS_ADC_CHAN_IIO(IN13, IIO_TEMP, IIO_CHAN_INFO_RAW),
827	PALMAS_ADC_CHAN_IIO(IN14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
828	PALMAS_ADC_CHAN_IIO(IN15, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
829};
830
831static int palmas_gpadc_get_adc_dt_data(struct platform_device *pdev,
832	struct palmas_gpadc_platform_data **gpadc_pdata)
833{
834	struct device_node *np = pdev->dev.of_node;
835	struct palmas_gpadc_platform_data *gp_data;
836	int ret;
837	u32 pval;
838
839	gp_data = devm_kzalloc(&pdev->dev, sizeof(*gp_data), GFP_KERNEL);
840	if (!gp_data)
841		return -ENOMEM;
842
843	ret = of_property_read_u32(np, "ti,channel0-current-microamp", &pval);
844	if (!ret)
845		gp_data->ch0_current = pval;
846
847	ret = of_property_read_u32(np, "ti,channel3-current-microamp", &pval);
848	if (!ret)
849		gp_data->ch3_current = pval;
850
851	gp_data->extended_delay = of_property_read_bool(np,
852					"ti,enable-extended-delay");
853
854	*gpadc_pdata = gp_data;
855
856	return 0;
857}
858
859static void palmas_gpadc_reset(void *data)
860{
861	struct palmas_gpadc *adc = data;
862	if (adc->event0.enabled || adc->event1.enabled)
863		palmas_adc_reset_events(adc);
864}
865
866static int palmas_gpadc_probe(struct platform_device *pdev)
867{
868	struct palmas_gpadc *adc;
869	struct palmas_platform_data *pdata;
870	struct palmas_gpadc_platform_data *gpadc_pdata = NULL;
871	struct iio_dev *indio_dev;
872	int ret, i;
873
874	pdata = dev_get_platdata(pdev->dev.parent);
875
876	if (pdata && pdata->gpadc_pdata)
877		gpadc_pdata = pdata->gpadc_pdata;
878
879	if (!gpadc_pdata && pdev->dev.of_node) {
880		ret = palmas_gpadc_get_adc_dt_data(pdev, &gpadc_pdata);
881		if (ret < 0)
882			return ret;
883	}
884	if (!gpadc_pdata)
885		return -EINVAL;
886
887	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc));
888	if (!indio_dev) {
889		dev_err(&pdev->dev, "iio_device_alloc failed\n");
890		return -ENOMEM;
891	}
892
893	adc = iio_priv(indio_dev);
894	adc->dev = &pdev->dev;
895	adc->palmas = dev_get_drvdata(pdev->dev.parent);
896	adc->adc_info = palmas_gpadc_info;
897
898	mutex_init(&adc->lock);
899
900	init_completion(&adc->conv_completion);
901	platform_set_drvdata(pdev, indio_dev);
902
903	adc->auto_conversion_period = gpadc_pdata->auto_conversion_period_ms;
904	adc->irq = palmas_irq_get_virq(adc->palmas, PALMAS_GPADC_EOC_SW_IRQ);
905	if (adc->irq < 0)
906		return dev_err_probe(adc->dev, adc->irq, "get virq failed\n");
907
908	ret = devm_request_threaded_irq(&pdev->dev, adc->irq, NULL,
909					palmas_gpadc_irq,
910					IRQF_ONESHOT, dev_name(adc->dev),
911					adc);
912	if (ret < 0)
913		return dev_err_probe(adc->dev, ret,
914				     "request irq %d failed\n", adc->irq);
915
916	adc->irq_auto_0 = platform_get_irq(pdev, 1);
917	if (adc->irq_auto_0 < 0)
918		return adc->irq_auto_0;
919
920	ret = devm_request_threaded_irq(&pdev->dev, adc->irq_auto_0, NULL,
921					palmas_gpadc_irq_auto, IRQF_ONESHOT,
922					"palmas-adc-auto-0", indio_dev);
923	if (ret < 0)
924		return dev_err_probe(adc->dev, ret,
925				     "request auto0 irq %d failed\n",
926				     adc->irq_auto_0);
927
928	adc->irq_auto_1 = platform_get_irq(pdev, 2);
929	if (adc->irq_auto_1 < 0)
930		return adc->irq_auto_1;
931
932	ret = devm_request_threaded_irq(&pdev->dev, adc->irq_auto_1, NULL,
933					palmas_gpadc_irq_auto, IRQF_ONESHOT,
934					"palmas-adc-auto-1", indio_dev);
935	if (ret < 0)
936		return dev_err_probe(adc->dev, ret,
937				     "request auto1 irq %d failed\n",
938				     adc->irq_auto_1);
939
940	adc->event0.enabled = false;
941	adc->event0.channel = -1;
942	adc->event0.direction = IIO_EV_DIR_NONE;
943	adc->event1.enabled = false;
944	adc->event1.channel = -1;
945	adc->event1.direction = IIO_EV_DIR_NONE;
946
947	/* set the current source 0 (value 0/5/15/20 uA => 0..3) */
948	if (gpadc_pdata->ch0_current <= 1)
949		adc->ch0_current = PALMAS_ADC_CH0_CURRENT_SRC_0;
950	else if (gpadc_pdata->ch0_current <= 5)
951		adc->ch0_current = PALMAS_ADC_CH0_CURRENT_SRC_5;
952	else if (gpadc_pdata->ch0_current <= 15)
953		adc->ch0_current = PALMAS_ADC_CH0_CURRENT_SRC_15;
954	else
955		adc->ch0_current = PALMAS_ADC_CH0_CURRENT_SRC_20;
956
957	/* set the current source 3 (value 0/10/400/800 uA => 0..3) */
958	if (gpadc_pdata->ch3_current <= 1)
959		adc->ch3_current = PALMAS_ADC_CH3_CURRENT_SRC_0;
960	else if (gpadc_pdata->ch3_current <= 10)
961		adc->ch3_current = PALMAS_ADC_CH3_CURRENT_SRC_10;
962	else if (gpadc_pdata->ch3_current <= 400)
963		adc->ch3_current = PALMAS_ADC_CH3_CURRENT_SRC_400;
964	else
965		adc->ch3_current = PALMAS_ADC_CH3_CURRENT_SRC_800;
966
967	adc->extended_delay = gpadc_pdata->extended_delay;
968
969	indio_dev->name = MOD_NAME;
970	indio_dev->info = &palmas_gpadc_iio_info;
971	indio_dev->modes = INDIO_DIRECT_MODE;
972	indio_dev->channels = palmas_gpadc_iio_channel;
973	indio_dev->num_channels = ARRAY_SIZE(palmas_gpadc_iio_channel);
974
975	ret = devm_iio_device_register(&pdev->dev, indio_dev);
976	if (ret < 0)
977		return dev_err_probe(adc->dev, ret,
978				     "iio_device_register() failed\n");
979
980	device_set_wakeup_capable(&pdev->dev, 1);
981	for (i = 0; i < PALMAS_ADC_CH_MAX; i++) {
982		if (!(adc->adc_info[i].is_uncalibrated))
983			palmas_gpadc_calibrate(adc, i);
984	}
985
986	ret = devm_add_action(&pdev->dev, palmas_gpadc_reset, adc);
987	if (ret)
988		return ret;
989
990	return 0;
991}
992
993static int palmas_adc_configure_events(struct palmas_gpadc *adc)
994{
995	int adc_period, conv;
996	int i;
997	int ch0 = 0, ch1 = 0;
998	int thres;
999	int ret;
1000
1001	adc_period = adc->auto_conversion_period;
1002	for (i = 0; i < 16; ++i) {
1003		if (((1000 * (1 << i)) / 32) >= adc_period)
1004			break;
1005	}
1006	if (i > 0)
1007		i--;
1008	adc_period = i;
1009	ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
1010			PALMAS_GPADC_AUTO_CTRL,
1011			PALMAS_GPADC_AUTO_CTRL_COUNTER_CONV_MASK,
1012			adc_period);
1013	if (ret < 0) {
1014		dev_err(adc->dev, "AUTO_CTRL write failed: %d\n", ret);
1015		return ret;
1016	}
1017
1018	conv = 0;
1019	if (adc->event0.enabled) {
1020		struct palmas_adc_event *ev = &adc->event0;
1021		int polarity;
1022
1023		ch0 = ev->channel;
1024		conv |= PALMAS_GPADC_AUTO_CTRL_AUTO_CONV0_EN;
1025		switch (ev->direction) {
1026		case IIO_EV_DIR_RISING:
1027			thres = palmas_gpadc_get_high_threshold_raw(adc, ev);
1028			polarity = 0;
1029			break;
1030		case IIO_EV_DIR_FALLING:
1031			thres = palmas_gpadc_get_low_threshold_raw(adc, ev);
1032			polarity = PALMAS_GPADC_THRES_CONV0_MSB_THRES_CONV0_POL;
1033			break;
1034		default:
1035			return -EINVAL;
1036		}
1037
1038		ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
1039				PALMAS_GPADC_THRES_CONV0_LSB, thres & 0xFF);
1040		if (ret < 0) {
1041			dev_err(adc->dev,
1042				"THRES_CONV0_LSB write failed: %d\n", ret);
1043			return ret;
1044		}
1045
1046		ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
1047				PALMAS_GPADC_THRES_CONV0_MSB,
1048				((thres >> 8) & 0xF) | polarity);
1049		if (ret < 0) {
1050			dev_err(adc->dev,
1051				"THRES_CONV0_MSB write failed: %d\n", ret);
1052			return ret;
1053		}
1054	}
1055
1056	if (adc->event1.enabled) {
1057		struct palmas_adc_event *ev = &adc->event1;
1058		int polarity;
1059
1060		ch1 = ev->channel;
1061		conv |= PALMAS_GPADC_AUTO_CTRL_AUTO_CONV1_EN;
1062		switch (ev->direction) {
1063		case IIO_EV_DIR_RISING:
1064			thres = palmas_gpadc_get_high_threshold_raw(adc, ev);
1065			polarity = 0;
1066			break;
1067		case IIO_EV_DIR_FALLING:
1068			thres = palmas_gpadc_get_low_threshold_raw(adc, ev);
1069			polarity = PALMAS_GPADC_THRES_CONV1_MSB_THRES_CONV1_POL;
1070			break;
1071		default:
1072			return -EINVAL;
1073		}
1074
1075		ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
1076				PALMAS_GPADC_THRES_CONV1_LSB, thres & 0xFF);
1077		if (ret < 0) {
1078			dev_err(adc->dev,
1079				"THRES_CONV1_LSB write failed: %d\n", ret);
1080			return ret;
1081		}
1082
1083		ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
1084				PALMAS_GPADC_THRES_CONV1_MSB,
1085				((thres >> 8) & 0xF) | polarity);
1086		if (ret < 0) {
1087			dev_err(adc->dev,
1088				"THRES_CONV1_MSB write failed: %d\n", ret);
1089			return ret;
1090		}
1091	}
1092
1093	ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
1094			PALMAS_GPADC_AUTO_SELECT, (ch1 << 4) | ch0);
1095	if (ret < 0) {
1096		dev_err(adc->dev, "AUTO_SELECT write failed: %d\n", ret);
1097		return ret;
1098	}
1099
1100	ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
1101			PALMAS_GPADC_AUTO_CTRL,
1102			PALMAS_GPADC_AUTO_CTRL_AUTO_CONV1_EN |
1103			PALMAS_GPADC_AUTO_CTRL_AUTO_CONV0_EN, conv);
1104	if (ret < 0)
1105		dev_err(adc->dev, "AUTO_CTRL write failed: %d\n", ret);
1106
1107	return ret;
1108}
1109
1110static int palmas_adc_reset_events(struct palmas_gpadc *adc)
1111{
1112	int ret;
1113
1114	ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
1115			PALMAS_GPADC_AUTO_SELECT, 0);
1116	if (ret < 0) {
1117		dev_err(adc->dev, "AUTO_SELECT write failed: %d\n", ret);
1118		return ret;
1119	}
1120
1121	ret = palmas_disable_auto_conversion(adc);
1122	if (ret < 0)
1123		dev_err(adc->dev, "Disable auto conversion failed: %d\n", ret);
1124
1125	return ret;
1126}
1127
1128static int palmas_gpadc_suspend(struct device *dev)
1129{
1130	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1131	struct palmas_gpadc *adc = iio_priv(indio_dev);
1132
1133	if (!device_may_wakeup(dev))
1134		return 0;
1135
1136	if (adc->event0.enabled)
1137		enable_irq_wake(adc->irq_auto_0);
1138
1139	if (adc->event1.enabled)
1140		enable_irq_wake(adc->irq_auto_1);
1141
1142	return 0;
1143}
1144
1145static int palmas_gpadc_resume(struct device *dev)
1146{
1147	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1148	struct palmas_gpadc *adc = iio_priv(indio_dev);
1149
1150	if (!device_may_wakeup(dev))
1151		return 0;
1152
1153	if (adc->event0.enabled)
1154		disable_irq_wake(adc->irq_auto_0);
1155
1156	if (adc->event1.enabled)
1157		disable_irq_wake(adc->irq_auto_1);
1158
1159	return 0;
1160};
1161
1162static DEFINE_SIMPLE_DEV_PM_OPS(palmas_pm_ops, palmas_gpadc_suspend,
1163				palmas_gpadc_resume);
1164
1165static const struct of_device_id of_palmas_gpadc_match_tbl[] = {
1166	{ .compatible = "ti,palmas-gpadc", },
1167	{ /* end */ }
1168};
1169MODULE_DEVICE_TABLE(of, of_palmas_gpadc_match_tbl);
1170
1171static struct platform_driver palmas_gpadc_driver = {
1172	.probe = palmas_gpadc_probe,
1173	.driver = {
1174		.name = MOD_NAME,
1175		.pm = pm_sleep_ptr(&palmas_pm_ops),
1176		.of_match_table = of_palmas_gpadc_match_tbl,
1177	},
1178};
1179module_platform_driver(palmas_gpadc_driver);
1180
1181MODULE_DESCRIPTION("palmas GPADC driver");
1182MODULE_AUTHOR("Pradeep Goudagunta<pgoudagunta@nvidia.com>");
1183MODULE_ALIAS("platform:palmas-gpadc");
1184MODULE_LICENSE("GPL v2");
1185