1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Freescale MXS LRADC ADC driver
4 *
5 * Copyright (c) 2012 DENX Software Engineering, GmbH.
6 * Copyright (c) 2017 Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
7 *
8 * Authors:
9 *  Marek Vasut <marex@denx.de>
10 *  Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
11 */
12
13#include <linux/completion.h>
14#include <linux/device.h>
15#include <linux/err.h>
16#include <linux/interrupt.h>
17#include <linux/mfd/core.h>
18#include <linux/mfd/mxs-lradc.h>
19#include <linux/module.h>
20#include <linux/of_irq.h>
21#include <linux/platform_device.h>
22#include <linux/sysfs.h>
23
24#include <linux/iio/buffer.h>
25#include <linux/iio/iio.h>
26#include <linux/iio/trigger.h>
27#include <linux/iio/trigger_consumer.h>
28#include <linux/iio/triggered_buffer.h>
29#include <linux/iio/sysfs.h>
30
31/*
32 * Make this runtime configurable if necessary. Currently, if the buffered mode
33 * is enabled, the LRADC takes LRADC_DELAY_TIMER_LOOP samples of data before
34 * triggering IRQ. The sampling happens every (LRADC_DELAY_TIMER_PER / 2000)
35 * seconds. The result is that the samples arrive every 500mS.
36 */
37#define LRADC_DELAY_TIMER_PER	200
38#define LRADC_DELAY_TIMER_LOOP	5
39
40#define VREF_MV_BASE 1850
41
42static const char *mx23_lradc_adc_irq_names[] = {
43	"mxs-lradc-channel0",
44	"mxs-lradc-channel1",
45	"mxs-lradc-channel2",
46	"mxs-lradc-channel3",
47	"mxs-lradc-channel4",
48	"mxs-lradc-channel5",
49};
50
51static const char *mx28_lradc_adc_irq_names[] = {
52	"mxs-lradc-thresh0",
53	"mxs-lradc-thresh1",
54	"mxs-lradc-channel0",
55	"mxs-lradc-channel1",
56	"mxs-lradc-channel2",
57	"mxs-lradc-channel3",
58	"mxs-lradc-channel4",
59	"mxs-lradc-channel5",
60	"mxs-lradc-button0",
61	"mxs-lradc-button1",
62};
63
64static const u32 mxs_lradc_adc_vref_mv[][LRADC_MAX_TOTAL_CHANS] = {
65	[IMX23_LRADC] = {
66		VREF_MV_BASE,		/* CH0 */
67		VREF_MV_BASE,		/* CH1 */
68		VREF_MV_BASE,		/* CH2 */
69		VREF_MV_BASE,		/* CH3 */
70		VREF_MV_BASE,		/* CH4 */
71		VREF_MV_BASE,		/* CH5 */
72		VREF_MV_BASE * 2,	/* CH6 VDDIO */
73		VREF_MV_BASE * 4,	/* CH7 VBATT */
74		VREF_MV_BASE,		/* CH8 Temp sense 0 */
75		VREF_MV_BASE,		/* CH9 Temp sense 1 */
76		VREF_MV_BASE,		/* CH10 */
77		VREF_MV_BASE,		/* CH11 */
78		VREF_MV_BASE,		/* CH12 USB_DP */
79		VREF_MV_BASE,		/* CH13 USB_DN */
80		VREF_MV_BASE,		/* CH14 VBG */
81		VREF_MV_BASE * 4,	/* CH15 VDD5V */
82	},
83	[IMX28_LRADC] = {
84		VREF_MV_BASE,		/* CH0 */
85		VREF_MV_BASE,		/* CH1 */
86		VREF_MV_BASE,		/* CH2 */
87		VREF_MV_BASE,		/* CH3 */
88		VREF_MV_BASE,		/* CH4 */
89		VREF_MV_BASE,		/* CH5 */
90		VREF_MV_BASE,		/* CH6 */
91		VREF_MV_BASE * 4,	/* CH7 VBATT */
92		VREF_MV_BASE,		/* CH8 Temp sense 0 */
93		VREF_MV_BASE,		/* CH9 Temp sense 1 */
94		VREF_MV_BASE * 2,	/* CH10 VDDIO */
95		VREF_MV_BASE,		/* CH11 VTH */
96		VREF_MV_BASE * 2,	/* CH12 VDDA */
97		VREF_MV_BASE,		/* CH13 VDDD */
98		VREF_MV_BASE,		/* CH14 VBG */
99		VREF_MV_BASE * 4,	/* CH15 VDD5V */
100	},
101};
102
103enum mxs_lradc_divbytwo {
104	MXS_LRADC_DIV_DISABLED = 0,
105	MXS_LRADC_DIV_ENABLED,
106};
107
108struct mxs_lradc_scale {
109	unsigned int		integer;
110	unsigned int		nano;
111};
112
113struct mxs_lradc_adc {
114	struct mxs_lradc	*lradc;
115	struct device		*dev;
116
117	void __iomem		*base;
118	/* Maximum of 8 channels + 8 byte ts */
119	u32			buffer[10] __aligned(8);
120	struct iio_trigger	*trig;
121	struct completion	completion;
122	spinlock_t		lock;
123
124	const u32		*vref_mv;
125	struct mxs_lradc_scale	scale_avail[LRADC_MAX_TOTAL_CHANS][2];
126	unsigned long		is_divided;
127};
128
129
130/* Raw I/O operations */
131static int mxs_lradc_adc_read_single(struct iio_dev *iio_dev, int chan,
132				     int *val)
133{
134	struct mxs_lradc_adc *adc = iio_priv(iio_dev);
135	struct mxs_lradc *lradc = adc->lradc;
136	int ret;
137
138	/*
139	 * See if there is no buffered operation in progress. If there is simply
140	 * bail out. This can be improved to support both buffered and raw IO at
141	 * the same time, yet the code becomes horribly complicated. Therefore I
142	 * applied KISS principle here.
143	 */
144	ret = iio_device_claim_direct_mode(iio_dev);
145	if (ret)
146		return ret;
147
148	reinit_completion(&adc->completion);
149
150	/*
151	 * No buffered operation in progress, map the channel and trigger it.
152	 * Virtual channel 0 is always used here as the others are always not
153	 * used if doing raw sampling.
154	 */
155	if (lradc->soc == IMX28_LRADC)
156		writel(LRADC_CTRL1_LRADC_IRQ_EN(0),
157		       adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
158	writel(0x1, adc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
159
160	/* Enable / disable the divider per requirement */
161	if (test_bit(chan, &adc->is_divided))
162		writel(1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
163		       adc->base + LRADC_CTRL2 + STMP_OFFSET_REG_SET);
164	else
165		writel(1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
166		       adc->base + LRADC_CTRL2 + STMP_OFFSET_REG_CLR);
167
168	/* Clean the slot's previous content, then set new one. */
169	writel(LRADC_CTRL4_LRADCSELECT_MASK(0),
170	       adc->base + LRADC_CTRL4 + STMP_OFFSET_REG_CLR);
171	writel(chan, adc->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET);
172
173	writel(0, adc->base + LRADC_CH(0));
174
175	/* Enable the IRQ and start sampling the channel. */
176	writel(LRADC_CTRL1_LRADC_IRQ_EN(0),
177	       adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);
178	writel(BIT(0), adc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
179
180	/* Wait for completion on the channel, 1 second max. */
181	ret = wait_for_completion_killable_timeout(&adc->completion, HZ);
182	if (!ret)
183		ret = -ETIMEDOUT;
184	if (ret < 0)
185		goto err;
186
187	/* Read the data. */
188	*val = readl(adc->base + LRADC_CH(0)) & LRADC_CH_VALUE_MASK;
189	ret = IIO_VAL_INT;
190
191err:
192	writel(LRADC_CTRL1_LRADC_IRQ_EN(0),
193	       adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
194
195	iio_device_release_direct_mode(iio_dev);
196
197	return ret;
198}
199
200static int mxs_lradc_adc_read_temp(struct iio_dev *iio_dev, int *val)
201{
202	int ret, min, max;
203
204	ret = mxs_lradc_adc_read_single(iio_dev, 8, &min);
205	if (ret != IIO_VAL_INT)
206		return ret;
207
208	ret = mxs_lradc_adc_read_single(iio_dev, 9, &max);
209	if (ret != IIO_VAL_INT)
210		return ret;
211
212	*val = max - min;
213
214	return IIO_VAL_INT;
215}
216
217static int mxs_lradc_adc_read_raw(struct iio_dev *iio_dev,
218			      const struct iio_chan_spec *chan,
219			      int *val, int *val2, long m)
220{
221	struct mxs_lradc_adc *adc = iio_priv(iio_dev);
222
223	switch (m) {
224	case IIO_CHAN_INFO_RAW:
225		if (chan->type == IIO_TEMP)
226			return mxs_lradc_adc_read_temp(iio_dev, val);
227
228		return mxs_lradc_adc_read_single(iio_dev, chan->channel, val);
229
230	case IIO_CHAN_INFO_SCALE:
231		if (chan->type == IIO_TEMP) {
232			/*
233			 * From the datasheet, we have to multiply by 1.012 and
234			 * divide by 4
235			 */
236			*val = 0;
237			*val2 = 253000;
238			return IIO_VAL_INT_PLUS_MICRO;
239		}
240
241		*val = adc->vref_mv[chan->channel];
242		*val2 = chan->scan_type.realbits -
243			test_bit(chan->channel, &adc->is_divided);
244		return IIO_VAL_FRACTIONAL_LOG2;
245
246	case IIO_CHAN_INFO_OFFSET:
247		if (chan->type == IIO_TEMP) {
248			/*
249			 * The calculated value from the ADC is in Kelvin, we
250			 * want Celsius for hwmon so the offset is -273.15
251			 * The offset is applied before scaling so it is
252			 * actually -213.15 * 4 / 1.012 = -1079.644268
253			 */
254			*val = -1079;
255			*val2 = 644268;
256
257			return IIO_VAL_INT_PLUS_MICRO;
258		}
259
260		return -EINVAL;
261
262	default:
263		break;
264	}
265
266	return -EINVAL;
267}
268
269static int mxs_lradc_adc_write_raw(struct iio_dev *iio_dev,
270				   const struct iio_chan_spec *chan,
271				   int val, int val2, long m)
272{
273	struct mxs_lradc_adc *adc = iio_priv(iio_dev);
274	struct mxs_lradc_scale *scale_avail =
275			adc->scale_avail[chan->channel];
276	int ret;
277
278	ret = iio_device_claim_direct_mode(iio_dev);
279	if (ret)
280		return ret;
281
282	switch (m) {
283	case IIO_CHAN_INFO_SCALE:
284		ret = -EINVAL;
285		if (val == scale_avail[MXS_LRADC_DIV_DISABLED].integer &&
286		    val2 == scale_avail[MXS_LRADC_DIV_DISABLED].nano) {
287			/* divider by two disabled */
288			clear_bit(chan->channel, &adc->is_divided);
289			ret = 0;
290		} else if (val == scale_avail[MXS_LRADC_DIV_ENABLED].integer &&
291			   val2 == scale_avail[MXS_LRADC_DIV_ENABLED].nano) {
292			/* divider by two enabled */
293			set_bit(chan->channel, &adc->is_divided);
294			ret = 0;
295		}
296
297		break;
298	default:
299		ret = -EINVAL;
300		break;
301	}
302
303	iio_device_release_direct_mode(iio_dev);
304
305	return ret;
306}
307
308static int mxs_lradc_adc_write_raw_get_fmt(struct iio_dev *iio_dev,
309					   const struct iio_chan_spec *chan,
310					   long m)
311{
312	return IIO_VAL_INT_PLUS_NANO;
313}
314
315static ssize_t mxs_lradc_adc_show_scale_avail(struct device *dev,
316						 struct device_attribute *attr,
317						 char *buf)
318{
319	struct iio_dev *iio = dev_to_iio_dev(dev);
320	struct mxs_lradc_adc *adc = iio_priv(iio);
321	struct iio_dev_attr *iio_attr = to_iio_dev_attr(attr);
322	int i, ch, len = 0;
323
324	ch = iio_attr->address;
325	for (i = 0; i < ARRAY_SIZE(adc->scale_avail[ch]); i++)
326		len += sprintf(buf + len, "%u.%09u ",
327			       adc->scale_avail[ch][i].integer,
328			       adc->scale_avail[ch][i].nano);
329
330	len += sprintf(buf + len, "\n");
331
332	return len;
333}
334
335#define SHOW_SCALE_AVAILABLE_ATTR(ch)\
336	IIO_DEVICE_ATTR(in_voltage##ch##_scale_available, 0444,\
337			mxs_lradc_adc_show_scale_avail, NULL, ch)
338
339static SHOW_SCALE_AVAILABLE_ATTR(0);
340static SHOW_SCALE_AVAILABLE_ATTR(1);
341static SHOW_SCALE_AVAILABLE_ATTR(2);
342static SHOW_SCALE_AVAILABLE_ATTR(3);
343static SHOW_SCALE_AVAILABLE_ATTR(4);
344static SHOW_SCALE_AVAILABLE_ATTR(5);
345static SHOW_SCALE_AVAILABLE_ATTR(6);
346static SHOW_SCALE_AVAILABLE_ATTR(7);
347static SHOW_SCALE_AVAILABLE_ATTR(10);
348static SHOW_SCALE_AVAILABLE_ATTR(11);
349static SHOW_SCALE_AVAILABLE_ATTR(12);
350static SHOW_SCALE_AVAILABLE_ATTR(13);
351static SHOW_SCALE_AVAILABLE_ATTR(14);
352static SHOW_SCALE_AVAILABLE_ATTR(15);
353
354static struct attribute *mxs_lradc_adc_attributes[] = {
355	&iio_dev_attr_in_voltage0_scale_available.dev_attr.attr,
356	&iio_dev_attr_in_voltage1_scale_available.dev_attr.attr,
357	&iio_dev_attr_in_voltage2_scale_available.dev_attr.attr,
358	&iio_dev_attr_in_voltage3_scale_available.dev_attr.attr,
359	&iio_dev_attr_in_voltage4_scale_available.dev_attr.attr,
360	&iio_dev_attr_in_voltage5_scale_available.dev_attr.attr,
361	&iio_dev_attr_in_voltage6_scale_available.dev_attr.attr,
362	&iio_dev_attr_in_voltage7_scale_available.dev_attr.attr,
363	&iio_dev_attr_in_voltage10_scale_available.dev_attr.attr,
364	&iio_dev_attr_in_voltage11_scale_available.dev_attr.attr,
365	&iio_dev_attr_in_voltage12_scale_available.dev_attr.attr,
366	&iio_dev_attr_in_voltage13_scale_available.dev_attr.attr,
367	&iio_dev_attr_in_voltage14_scale_available.dev_attr.attr,
368	&iio_dev_attr_in_voltage15_scale_available.dev_attr.attr,
369	NULL
370};
371
372static const struct attribute_group mxs_lradc_adc_attribute_group = {
373	.attrs = mxs_lradc_adc_attributes,
374};
375
376static const struct iio_info mxs_lradc_adc_iio_info = {
377	.read_raw		= mxs_lradc_adc_read_raw,
378	.write_raw		= mxs_lradc_adc_write_raw,
379	.write_raw_get_fmt	= mxs_lradc_adc_write_raw_get_fmt,
380	.attrs			= &mxs_lradc_adc_attribute_group,
381};
382
383/* IRQ Handling */
384static irqreturn_t mxs_lradc_adc_handle_irq(int irq, void *data)
385{
386	struct iio_dev *iio = data;
387	struct mxs_lradc_adc *adc = iio_priv(iio);
388	struct mxs_lradc *lradc = adc->lradc;
389	unsigned long reg = readl(adc->base + LRADC_CTRL1);
390	unsigned long flags;
391
392	if (!(reg & mxs_lradc_irq_mask(lradc)))
393		return IRQ_NONE;
394
395	if (iio_buffer_enabled(iio)) {
396		if (reg & lradc->buffer_vchans) {
397			spin_lock_irqsave(&adc->lock, flags);
398			iio_trigger_poll(iio->trig);
399			spin_unlock_irqrestore(&adc->lock, flags);
400		}
401	} else if (reg & LRADC_CTRL1_LRADC_IRQ(0)) {
402		complete(&adc->completion);
403	}
404
405	writel(reg & mxs_lradc_irq_mask(lradc),
406	       adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
407
408	return IRQ_HANDLED;
409}
410
411
412/* Trigger handling */
413static irqreturn_t mxs_lradc_adc_trigger_handler(int irq, void *p)
414{
415	struct iio_poll_func *pf = p;
416	struct iio_dev *iio = pf->indio_dev;
417	struct mxs_lradc_adc *adc = iio_priv(iio);
418	const u32 chan_value = LRADC_CH_ACCUMULATE |
419		((LRADC_DELAY_TIMER_LOOP - 1) << LRADC_CH_NUM_SAMPLES_OFFSET);
420	unsigned int i, j = 0;
421
422	for_each_set_bit(i, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {
423		adc->buffer[j] = readl(adc->base + LRADC_CH(j));
424		writel(chan_value, adc->base + LRADC_CH(j));
425		adc->buffer[j] &= LRADC_CH_VALUE_MASK;
426		adc->buffer[j] /= LRADC_DELAY_TIMER_LOOP;
427		j++;
428	}
429
430	iio_push_to_buffers_with_timestamp(iio, adc->buffer, pf->timestamp);
431
432	iio_trigger_notify_done(iio->trig);
433
434	return IRQ_HANDLED;
435}
436
437static int mxs_lradc_adc_configure_trigger(struct iio_trigger *trig, bool state)
438{
439	struct iio_dev *iio = iio_trigger_get_drvdata(trig);
440	struct mxs_lradc_adc *adc = iio_priv(iio);
441	const u32 st = state ? STMP_OFFSET_REG_SET : STMP_OFFSET_REG_CLR;
442
443	writel(LRADC_DELAY_KICK, adc->base + (LRADC_DELAY(0) + st));
444
445	return 0;
446}
447
448static const struct iio_trigger_ops mxs_lradc_adc_trigger_ops = {
449	.set_trigger_state = &mxs_lradc_adc_configure_trigger,
450};
451
452static int mxs_lradc_adc_trigger_init(struct iio_dev *iio)
453{
454	int ret;
455	struct iio_trigger *trig;
456	struct mxs_lradc_adc *adc = iio_priv(iio);
457
458	trig = devm_iio_trigger_alloc(&iio->dev, "%s-dev%i", iio->name,
459				      iio_device_id(iio));
460	if (!trig)
461		return -ENOMEM;
462
463	trig->dev.parent = adc->dev;
464	iio_trigger_set_drvdata(trig, iio);
465	trig->ops = &mxs_lradc_adc_trigger_ops;
466
467	ret = iio_trigger_register(trig);
468	if (ret)
469		return ret;
470
471	adc->trig = trig;
472
473	return 0;
474}
475
476static void mxs_lradc_adc_trigger_remove(struct iio_dev *iio)
477{
478	struct mxs_lradc_adc *adc = iio_priv(iio);
479
480	iio_trigger_unregister(adc->trig);
481}
482
483static int mxs_lradc_adc_buffer_preenable(struct iio_dev *iio)
484{
485	struct mxs_lradc_adc *adc = iio_priv(iio);
486	struct mxs_lradc *lradc = adc->lradc;
487	int chan, ofs = 0;
488	unsigned long enable = 0;
489	u32 ctrl4_set = 0;
490	u32 ctrl4_clr = 0;
491	u32 ctrl1_irq = 0;
492	const u32 chan_value = LRADC_CH_ACCUMULATE |
493		((LRADC_DELAY_TIMER_LOOP - 1) << LRADC_CH_NUM_SAMPLES_OFFSET);
494
495	if (lradc->soc == IMX28_LRADC)
496		writel(lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
497		       adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
498	writel(lradc->buffer_vchans,
499	       adc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
500
501	for_each_set_bit(chan, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {
502		ctrl4_set |= chan << LRADC_CTRL4_LRADCSELECT_OFFSET(ofs);
503		ctrl4_clr |= LRADC_CTRL4_LRADCSELECT_MASK(ofs);
504		ctrl1_irq |= LRADC_CTRL1_LRADC_IRQ_EN(ofs);
505		writel(chan_value, adc->base + LRADC_CH(ofs));
506		bitmap_set(&enable, ofs, 1);
507		ofs++;
508	}
509
510	writel(LRADC_DELAY_TRIGGER_LRADCS_MASK | LRADC_DELAY_KICK,
511	       adc->base + LRADC_DELAY(0) + STMP_OFFSET_REG_CLR);
512	writel(ctrl4_clr, adc->base + LRADC_CTRL4 + STMP_OFFSET_REG_CLR);
513	writel(ctrl4_set, adc->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET);
514	writel(ctrl1_irq, adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);
515	writel(enable << LRADC_DELAY_TRIGGER_LRADCS_OFFSET,
516	       adc->base + LRADC_DELAY(0) + STMP_OFFSET_REG_SET);
517
518	return 0;
519}
520
521static int mxs_lradc_adc_buffer_postdisable(struct iio_dev *iio)
522{
523	struct mxs_lradc_adc *adc = iio_priv(iio);
524	struct mxs_lradc *lradc = adc->lradc;
525
526	writel(LRADC_DELAY_TRIGGER_LRADCS_MASK | LRADC_DELAY_KICK,
527	       adc->base + LRADC_DELAY(0) + STMP_OFFSET_REG_CLR);
528
529	writel(lradc->buffer_vchans,
530	       adc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
531	if (lradc->soc == IMX28_LRADC)
532		writel(lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
533		       adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
534
535	return 0;
536}
537
538static bool mxs_lradc_adc_validate_scan_mask(struct iio_dev *iio,
539					     const unsigned long *mask)
540{
541	struct mxs_lradc_adc *adc = iio_priv(iio);
542	struct mxs_lradc *lradc = adc->lradc;
543	const int map_chans = bitmap_weight(mask, LRADC_MAX_TOTAL_CHANS);
544	int rsvd_chans = 0;
545	unsigned long rsvd_mask = 0;
546
547	if (lradc->use_touchbutton)
548		rsvd_mask |= CHAN_MASK_TOUCHBUTTON;
549	if (lradc->touchscreen_wire == MXS_LRADC_TOUCHSCREEN_4WIRE)
550		rsvd_mask |= CHAN_MASK_TOUCHSCREEN_4WIRE;
551	if (lradc->touchscreen_wire == MXS_LRADC_TOUCHSCREEN_5WIRE)
552		rsvd_mask |= CHAN_MASK_TOUCHSCREEN_5WIRE;
553
554	if (lradc->use_touchbutton)
555		rsvd_chans++;
556	if (lradc->touchscreen_wire)
557		rsvd_chans += 2;
558
559	/* Test for attempts to map channels with special mode of operation. */
560	if (bitmap_intersects(mask, &rsvd_mask, LRADC_MAX_TOTAL_CHANS))
561		return false;
562
563	/* Test for attempts to map more channels then available slots. */
564	if (map_chans + rsvd_chans > LRADC_MAX_MAPPED_CHANS)
565		return false;
566
567	return true;
568}
569
570static const struct iio_buffer_setup_ops mxs_lradc_adc_buffer_ops = {
571	.preenable = &mxs_lradc_adc_buffer_preenable,
572	.postdisable = &mxs_lradc_adc_buffer_postdisable,
573	.validate_scan_mask = &mxs_lradc_adc_validate_scan_mask,
574};
575
576/* Driver initialization */
577#define MXS_ADC_CHAN(idx, chan_type, name) {			\
578	.type = (chan_type),					\
579	.indexed = 1,						\
580	.scan_index = (idx),					\
581	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
582			      BIT(IIO_CHAN_INFO_SCALE),		\
583	.channel = (idx),					\
584	.address = (idx),					\
585	.scan_type = {						\
586		.sign = 'u',					\
587		.realbits = LRADC_RESOLUTION,			\
588		.storagebits = 32,				\
589	},							\
590	.datasheet_name = (name),				\
591}
592
593static const struct iio_chan_spec mx23_lradc_chan_spec[] = {
594	MXS_ADC_CHAN(0, IIO_VOLTAGE, "LRADC0"),
595	MXS_ADC_CHAN(1, IIO_VOLTAGE, "LRADC1"),
596	MXS_ADC_CHAN(2, IIO_VOLTAGE, "LRADC2"),
597	MXS_ADC_CHAN(3, IIO_VOLTAGE, "LRADC3"),
598	MXS_ADC_CHAN(4, IIO_VOLTAGE, "LRADC4"),
599	MXS_ADC_CHAN(5, IIO_VOLTAGE, "LRADC5"),
600	MXS_ADC_CHAN(6, IIO_VOLTAGE, "VDDIO"),
601	MXS_ADC_CHAN(7, IIO_VOLTAGE, "VBATT"),
602	/* Combined Temperature sensors */
603	{
604		.type = IIO_TEMP,
605		.indexed = 1,
606		.scan_index = 8,
607		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
608				      BIT(IIO_CHAN_INFO_OFFSET) |
609				      BIT(IIO_CHAN_INFO_SCALE),
610		.channel = 8,
611		.scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,},
612		.datasheet_name = "TEMP_DIE",
613	},
614	/* Hidden channel to keep indexes */
615	{
616		.type = IIO_TEMP,
617		.indexed = 1,
618		.scan_index = -1,
619		.channel = 9,
620	},
621	MXS_ADC_CHAN(10, IIO_VOLTAGE, NULL),
622	MXS_ADC_CHAN(11, IIO_VOLTAGE, NULL),
623	MXS_ADC_CHAN(12, IIO_VOLTAGE, "USB_DP"),
624	MXS_ADC_CHAN(13, IIO_VOLTAGE, "USB_DN"),
625	MXS_ADC_CHAN(14, IIO_VOLTAGE, "VBG"),
626	MXS_ADC_CHAN(15, IIO_VOLTAGE, "VDD5V"),
627};
628
629static const struct iio_chan_spec mx28_lradc_chan_spec[] = {
630	MXS_ADC_CHAN(0, IIO_VOLTAGE, "LRADC0"),
631	MXS_ADC_CHAN(1, IIO_VOLTAGE, "LRADC1"),
632	MXS_ADC_CHAN(2, IIO_VOLTAGE, "LRADC2"),
633	MXS_ADC_CHAN(3, IIO_VOLTAGE, "LRADC3"),
634	MXS_ADC_CHAN(4, IIO_VOLTAGE, "LRADC4"),
635	MXS_ADC_CHAN(5, IIO_VOLTAGE, "LRADC5"),
636	MXS_ADC_CHAN(6, IIO_VOLTAGE, "LRADC6"),
637	MXS_ADC_CHAN(7, IIO_VOLTAGE, "VBATT"),
638	/* Combined Temperature sensors */
639	{
640		.type = IIO_TEMP,
641		.indexed = 1,
642		.scan_index = 8,
643		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
644				      BIT(IIO_CHAN_INFO_OFFSET) |
645				      BIT(IIO_CHAN_INFO_SCALE),
646		.channel = 8,
647		.scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,},
648		.datasheet_name = "TEMP_DIE",
649	},
650	/* Hidden channel to keep indexes */
651	{
652		.type = IIO_TEMP,
653		.indexed = 1,
654		.scan_index = -1,
655		.channel = 9,
656	},
657	MXS_ADC_CHAN(10, IIO_VOLTAGE, "VDDIO"),
658	MXS_ADC_CHAN(11, IIO_VOLTAGE, "VTH"),
659	MXS_ADC_CHAN(12, IIO_VOLTAGE, "VDDA"),
660	MXS_ADC_CHAN(13, IIO_VOLTAGE, "VDDD"),
661	MXS_ADC_CHAN(14, IIO_VOLTAGE, "VBG"),
662	MXS_ADC_CHAN(15, IIO_VOLTAGE, "VDD5V"),
663};
664
665static void mxs_lradc_adc_hw_init(struct mxs_lradc_adc *adc)
666{
667	/* The ADC always uses DELAY CHANNEL 0. */
668	const u32 adc_cfg =
669		(1 << (LRADC_DELAY_TRIGGER_DELAYS_OFFSET + 0)) |
670		(LRADC_DELAY_TIMER_PER << LRADC_DELAY_DELAY_OFFSET);
671
672	/* Configure DELAY CHANNEL 0 for generic ADC sampling. */
673	writel(adc_cfg, adc->base + LRADC_DELAY(0));
674
675	/*
676	 * Start internal temperature sensing by clearing bit
677	 * HW_LRADC_CTRL2_TEMPSENSE_PWD. This bit can be left cleared
678	 * after power up.
679	 */
680	writel(0, adc->base + LRADC_CTRL2);
681}
682
683static void mxs_lradc_adc_hw_stop(struct mxs_lradc_adc *adc)
684{
685	writel(0, adc->base + LRADC_DELAY(0));
686}
687
688static int mxs_lradc_adc_probe(struct platform_device *pdev)
689{
690	struct device *dev = &pdev->dev;
691	struct mxs_lradc *lradc = dev_get_drvdata(dev->parent);
692	struct mxs_lradc_adc *adc;
693	struct iio_dev *iio;
694	struct resource *iores;
695	int ret, irq, virq, i, s, n;
696	u64 scale_uv;
697	const char **irq_name;
698
699	/* Allocate the IIO device. */
700	iio = devm_iio_device_alloc(dev, sizeof(*adc));
701	if (!iio) {
702		dev_err(dev, "Failed to allocate IIO device\n");
703		return -ENOMEM;
704	}
705
706	adc = iio_priv(iio);
707	adc->lradc = lradc;
708	adc->dev = dev;
709
710	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
711	if (!iores)
712		return -EINVAL;
713
714	adc->base = devm_ioremap(dev, iores->start, resource_size(iores));
715	if (!adc->base)
716		return -ENOMEM;
717
718	init_completion(&adc->completion);
719	spin_lock_init(&adc->lock);
720
721	platform_set_drvdata(pdev, iio);
722
723	iio->name = pdev->name;
724	iio->dev.of_node = dev->parent->of_node;
725	iio->info = &mxs_lradc_adc_iio_info;
726	iio->modes = INDIO_DIRECT_MODE;
727	iio->masklength = LRADC_MAX_TOTAL_CHANS;
728
729	if (lradc->soc == IMX23_LRADC) {
730		iio->channels = mx23_lradc_chan_spec;
731		iio->num_channels = ARRAY_SIZE(mx23_lradc_chan_spec);
732		irq_name = mx23_lradc_adc_irq_names;
733		n = ARRAY_SIZE(mx23_lradc_adc_irq_names);
734	} else {
735		iio->channels = mx28_lradc_chan_spec;
736		iio->num_channels = ARRAY_SIZE(mx28_lradc_chan_spec);
737		irq_name = mx28_lradc_adc_irq_names;
738		n = ARRAY_SIZE(mx28_lradc_adc_irq_names);
739	}
740
741	ret = stmp_reset_block(adc->base);
742	if (ret)
743		return ret;
744
745	for (i = 0; i < n; i++) {
746		irq = platform_get_irq_byname(pdev, irq_name[i]);
747		if (irq < 0)
748			return irq;
749
750		virq = irq_of_parse_and_map(dev->parent->of_node, irq);
751
752		ret = devm_request_irq(dev, virq, mxs_lradc_adc_handle_irq,
753				       0, irq_name[i], iio);
754		if (ret)
755			return ret;
756	}
757
758	ret = mxs_lradc_adc_trigger_init(iio);
759	if (ret)
760		return ret;
761
762	ret = iio_triggered_buffer_setup(iio, &iio_pollfunc_store_time,
763					 &mxs_lradc_adc_trigger_handler,
764					 &mxs_lradc_adc_buffer_ops);
765	if (ret)
766		goto err_trig;
767
768	adc->vref_mv = mxs_lradc_adc_vref_mv[lradc->soc];
769
770	/* Populate available ADC input ranges */
771	for (i = 0; i < LRADC_MAX_TOTAL_CHANS; i++) {
772		for (s = 0; s < ARRAY_SIZE(adc->scale_avail[i]); s++) {
773			/*
774			 * [s=0] = optional divider by two disabled (default)
775			 * [s=1] = optional divider by two enabled
776			 *
777			 * The scale is calculated by doing:
778			 *   Vref >> (realbits - s)
779			 * which multiplies by two on the second component
780			 * of the array.
781			 */
782			scale_uv = ((u64)adc->vref_mv[i] * 100000000) >>
783				   (LRADC_RESOLUTION - s);
784			adc->scale_avail[i][s].nano =
785					do_div(scale_uv, 100000000) * 10;
786			adc->scale_avail[i][s].integer = scale_uv;
787		}
788	}
789
790	/* Configure the hardware. */
791	mxs_lradc_adc_hw_init(adc);
792
793	/* Register IIO device. */
794	ret = iio_device_register(iio);
795	if (ret) {
796		dev_err(dev, "Failed to register IIO device\n");
797		goto err_dev;
798	}
799
800	return 0;
801
802err_dev:
803	mxs_lradc_adc_hw_stop(adc);
804	iio_triggered_buffer_cleanup(iio);
805err_trig:
806	mxs_lradc_adc_trigger_remove(iio);
807	return ret;
808}
809
810static void mxs_lradc_adc_remove(struct platform_device *pdev)
811{
812	struct iio_dev *iio = platform_get_drvdata(pdev);
813	struct mxs_lradc_adc *adc = iio_priv(iio);
814
815	iio_device_unregister(iio);
816	mxs_lradc_adc_hw_stop(adc);
817	iio_triggered_buffer_cleanup(iio);
818	mxs_lradc_adc_trigger_remove(iio);
819}
820
821static struct platform_driver mxs_lradc_adc_driver = {
822	.driver = {
823		.name	= "mxs-lradc-adc",
824	},
825	.probe	= mxs_lradc_adc_probe,
826	.remove_new = mxs_lradc_adc_remove,
827};
828module_platform_driver(mxs_lradc_adc_driver);
829
830MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
831MODULE_DESCRIPTION("Freescale MXS LRADC driver general purpose ADC driver");
832MODULE_LICENSE("GPL");
833MODULE_ALIAS("platform:mxs-lradc-adc");
834