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WIP FPC-III support
[linux/fpc-iii.git] / drivers / iio / adc / mxs-lradc-adc.c
blob30e29f44ebd2ee6bf3ac8bc950a8e043f44ae214
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
42 static 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
51 static 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
64 static 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
103 enum mxs_lradc_divbytwo {
104 MXS_LRADC_DIV_DISABLED = 0,
105 MXS_LRADC_DIV_ENABLED,
106 };
107
108 struct mxs_lradc_scale {
109 unsigned int integer;
110 unsigned int nano;
111 };
112
113 struct mxs_lradc_adc {
114 struct mxs_lradc *lradc;
115 struct device *dev;
116
117 void __iomem *base;
118 u32 buffer[10];
119 struct iio_trigger *trig;
120 struct completion completion;
121 spinlock_t lock;
122
123 const u32 *vref_mv;
124 struct mxs_lradc_scale scale_avail[LRADC_MAX_TOTAL_CHANS][2];
125 unsigned long is_divided;
126 };
127
128
129 /* Raw I/O operations */
130 static int mxs_lradc_adc_read_single(struct iio_dev *iio_dev, int chan,
131 int *val)
132 {
133 struct mxs_lradc_adc *adc = iio_priv(iio_dev);
134 struct mxs_lradc *lradc = adc->lradc;
135 int ret;
136
137 /*
138 * See if there is no buffered operation in progress. If there is simply
139 * bail out. This can be improved to support both buffered and raw IO at
140 * the same time, yet the code becomes horribly complicated. Therefore I
141 * applied KISS principle here.
142 */
143 ret = iio_device_claim_direct_mode(iio_dev);
144 if (ret)
145 return ret;
146
147 reinit_completion(&adc->completion);
148
149 /*
150 * No buffered operation in progress, map the channel and trigger it.
151 * Virtual channel 0 is always used here as the others are always not
152 * used if doing raw sampling.
153 */
154 if (lradc->soc == IMX28_LRADC)
155 writel(LRADC_CTRL1_LRADC_IRQ_EN(0),
156 adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
157 writel(0x1, adc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
158
159 /* Enable / disable the divider per requirement */
160 if (test_bit(chan, &adc->is_divided))
161 writel(1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
162 adc->base + LRADC_CTRL2 + STMP_OFFSET_REG_SET);
163 else
164 writel(1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
165 adc->base + LRADC_CTRL2 + STMP_OFFSET_REG_CLR);
166
167 /* Clean the slot's previous content, then set new one. */
168 writel(LRADC_CTRL4_LRADCSELECT_MASK(0),
169 adc->base + LRADC_CTRL4 + STMP_OFFSET_REG_CLR);
170 writel(chan, adc->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET);
171
172 writel(0, adc->base + LRADC_CH(0));
173
174 /* Enable the IRQ and start sampling the channel. */
175 writel(LRADC_CTRL1_LRADC_IRQ_EN(0),
176 adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);
177 writel(BIT(0), adc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
178
179 /* Wait for completion on the channel, 1 second max. */
180 ret = wait_for_completion_killable_timeout(&adc->completion, HZ);
181 if (!ret)
182 ret = -ETIMEDOUT;
183 if (ret < 0)
184 goto err;
185
186 /* Read the data. */
187 *val = readl(adc->base + LRADC_CH(0)) & LRADC_CH_VALUE_MASK;
188 ret = IIO_VAL_INT;
189
190 err:
191 writel(LRADC_CTRL1_LRADC_IRQ_EN(0),
192 adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
193
194 iio_device_release_direct_mode(iio_dev);
195
196 return ret;
197 }
198
199 static int mxs_lradc_adc_read_temp(struct iio_dev *iio_dev, int *val)
200 {
201 int ret, min, max;
202
203 ret = mxs_lradc_adc_read_single(iio_dev, 8, &min);
204 if (ret != IIO_VAL_INT)
205 return ret;
206
207 ret = mxs_lradc_adc_read_single(iio_dev, 9, &max);
208 if (ret != IIO_VAL_INT)
209 return ret;
210
211 *val = max - min;
212
213 return IIO_VAL_INT;
214 }
215
216 static int mxs_lradc_adc_read_raw(struct iio_dev *iio_dev,
217 const struct iio_chan_spec *chan,
218 int *val, int *val2, long m)
219 {
220 struct mxs_lradc_adc *adc = iio_priv(iio_dev);
221
222 switch (m) {
223 case IIO_CHAN_INFO_RAW:
224 if (chan->type == IIO_TEMP)
225 return mxs_lradc_adc_read_temp(iio_dev, val);
226
227 return mxs_lradc_adc_read_single(iio_dev, chan->channel, val);
228
229 case IIO_CHAN_INFO_SCALE:
230 if (chan->type == IIO_TEMP) {
231 /*
232 * From the datasheet, we have to multiply by 1.012 and
233 * divide by 4
234 */
235 *val = 0;
236 *val2 = 253000;
237 return IIO_VAL_INT_PLUS_MICRO;
238 }
239
240 *val = adc->vref_mv[chan->channel];
241 *val2 = chan->scan_type.realbits -
242 test_bit(chan->channel, &adc->is_divided);
243 return IIO_VAL_FRACTIONAL_LOG2;
244
245 case IIO_CHAN_INFO_OFFSET:
246 if (chan->type == IIO_TEMP) {
247 /*
248 * The calculated value from the ADC is in Kelvin, we
249 * want Celsius for hwmon so the offset is -273.15
250 * The offset is applied before scaling so it is
251 * actually -213.15 * 4 / 1.012 = -1079.644268
252 */
253 *val = -1079;
254 *val2 = 644268;
255
256 return IIO_VAL_INT_PLUS_MICRO;
257 }
258
259 return -EINVAL;
260
261 default:
262 break;
263 }
264
265 return -EINVAL;
266 }
267
268 static int mxs_lradc_adc_write_raw(struct iio_dev *iio_dev,
269 const struct iio_chan_spec *chan,
270 int val, int val2, long m)
271 {
272 struct mxs_lradc_adc *adc = iio_priv(iio_dev);
273 struct mxs_lradc_scale *scale_avail =
274 adc->scale_avail[chan->channel];
275 int ret;
276
277 ret = iio_device_claim_direct_mode(iio_dev);
278 if (ret)
279 return ret;
280
281 switch (m) {
282 case IIO_CHAN_INFO_SCALE:
283 ret = -EINVAL;
284 if (val == scale_avail[MXS_LRADC_DIV_DISABLED].integer &&
285 val2 == scale_avail[MXS_LRADC_DIV_DISABLED].nano) {
286 /* divider by two disabled */
287 clear_bit(chan->channel, &adc->is_divided);
288 ret = 0;
289 } else if (val == scale_avail[MXS_LRADC_DIV_ENABLED].integer &&
290 val2 == scale_avail[MXS_LRADC_DIV_ENABLED].nano) {
291 /* divider by two enabled */
292 set_bit(chan->channel, &adc->is_divided);
293 ret = 0;
294 }
295
296 break;
297 default:
298 ret = -EINVAL;
299 break;
300 }
301
302 iio_device_release_direct_mode(iio_dev);
303
304 return ret;
305 }
306
307 static int mxs_lradc_adc_write_raw_get_fmt(struct iio_dev *iio_dev,
308 const struct iio_chan_spec *chan,
309 long m)
310 {
311 return IIO_VAL_INT_PLUS_NANO;
312 }
313
314 static ssize_t mxs_lradc_adc_show_scale_avail(struct device *dev,
315 struct device_attribute *attr,
316 char *buf)
317 {
318 struct iio_dev *iio = dev_to_iio_dev(dev);
319 struct mxs_lradc_adc *adc = iio_priv(iio);
320 struct iio_dev_attr *iio_attr = to_iio_dev_attr(attr);
321 int i, ch, len = 0;
322
323 ch = iio_attr->address;
324 for (i = 0; i < ARRAY_SIZE(adc->scale_avail[ch]); i++)
325 len += sprintf(buf + len, "%u.%09u ",
326 adc->scale_avail[ch][i].integer,
327 adc->scale_avail[ch][i].nano);
328
329 len += sprintf(buf + len, "\n");
330
331 return len;
332 }
333
334 #define SHOW_SCALE_AVAILABLE_ATTR(ch)\
335 IIO_DEVICE_ATTR(in_voltage##ch##_scale_available, 0444,\
336 mxs_lradc_adc_show_scale_avail, NULL, ch)
337
338 static SHOW_SCALE_AVAILABLE_ATTR(0);
339 static SHOW_SCALE_AVAILABLE_ATTR(1);
340 static SHOW_SCALE_AVAILABLE_ATTR(2);
341 static SHOW_SCALE_AVAILABLE_ATTR(3);
342 static SHOW_SCALE_AVAILABLE_ATTR(4);
343 static SHOW_SCALE_AVAILABLE_ATTR(5);
344 static SHOW_SCALE_AVAILABLE_ATTR(6);
345 static SHOW_SCALE_AVAILABLE_ATTR(7);
346 static SHOW_SCALE_AVAILABLE_ATTR(10);
347 static SHOW_SCALE_AVAILABLE_ATTR(11);
348 static SHOW_SCALE_AVAILABLE_ATTR(12);
349 static SHOW_SCALE_AVAILABLE_ATTR(13);
350 static SHOW_SCALE_AVAILABLE_ATTR(14);
351 static SHOW_SCALE_AVAILABLE_ATTR(15);
352
353 static struct attribute *mxs_lradc_adc_attributes[] = {
354 &iio_dev_attr_in_voltage0_scale_available.dev_attr.attr,
355 &iio_dev_attr_in_voltage1_scale_available.dev_attr.attr,
356 &iio_dev_attr_in_voltage2_scale_available.dev_attr.attr,
357 &iio_dev_attr_in_voltage3_scale_available.dev_attr.attr,
358 &iio_dev_attr_in_voltage4_scale_available.dev_attr.attr,
359 &iio_dev_attr_in_voltage5_scale_available.dev_attr.attr,
360 &iio_dev_attr_in_voltage6_scale_available.dev_attr.attr,
361 &iio_dev_attr_in_voltage7_scale_available.dev_attr.attr,
362 &iio_dev_attr_in_voltage10_scale_available.dev_attr.attr,
363 &iio_dev_attr_in_voltage11_scale_available.dev_attr.attr,
364 &iio_dev_attr_in_voltage12_scale_available.dev_attr.attr,
365 &iio_dev_attr_in_voltage13_scale_available.dev_attr.attr,
366 &iio_dev_attr_in_voltage14_scale_available.dev_attr.attr,
367 &iio_dev_attr_in_voltage15_scale_available.dev_attr.attr,
368 NULL
369 };
370
371 static const struct attribute_group mxs_lradc_adc_attribute_group = {
372 .attrs = mxs_lradc_adc_attributes,
373 };
374
375 static const struct iio_info mxs_lradc_adc_iio_info = {
376 .read_raw = mxs_lradc_adc_read_raw,
377 .write_raw = mxs_lradc_adc_write_raw,
378 .write_raw_get_fmt = mxs_lradc_adc_write_raw_get_fmt,
379 .attrs = &mxs_lradc_adc_attribute_group,
380 };
381
382 /* IRQ Handling */
383 static irqreturn_t mxs_lradc_adc_handle_irq(int irq, void *data)
384 {
385 struct iio_dev *iio = data;
386 struct mxs_lradc_adc *adc = iio_priv(iio);
387 struct mxs_lradc *lradc = adc->lradc;
388 unsigned long reg = readl(adc->base + LRADC_CTRL1);
389 unsigned long flags;
390
391 if (!(reg & mxs_lradc_irq_mask(lradc)))
392 return IRQ_NONE;
393
394 if (iio_buffer_enabled(iio)) {
395 if (reg & lradc->buffer_vchans) {
396 spin_lock_irqsave(&adc->lock, flags);
397 iio_trigger_poll(iio->trig);
398 spin_unlock_irqrestore(&adc->lock, flags);
399 }
400 } else if (reg & LRADC_CTRL1_LRADC_IRQ(0)) {
401 complete(&adc->completion);
402 }
403
404 writel(reg & mxs_lradc_irq_mask(lradc),
405 adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
406
407 return IRQ_HANDLED;
408 }
409
410
411 /* Trigger handling */
412 static irqreturn_t mxs_lradc_adc_trigger_handler(int irq, void *p)
413 {
414 struct iio_poll_func *pf = p;
415 struct iio_dev *iio = pf->indio_dev;
416 struct mxs_lradc_adc *adc = iio_priv(iio);
417 const u32 chan_value = LRADC_CH_ACCUMULATE |
418 ((LRADC_DELAY_TIMER_LOOP - 1) << LRADC_CH_NUM_SAMPLES_OFFSET);
419 unsigned int i, j = 0;
420
421 for_each_set_bit(i, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {
422 adc->buffer[j] = readl(adc->base + LRADC_CH(j));
423 writel(chan_value, adc->base + LRADC_CH(j));
424 adc->buffer[j] &= LRADC_CH_VALUE_MASK;
425 adc->buffer[j] /= LRADC_DELAY_TIMER_LOOP;
426 j++;
427 }
428
429 iio_push_to_buffers_with_timestamp(iio, adc->buffer, pf->timestamp);
430
431 iio_trigger_notify_done(iio->trig);
432
433 return IRQ_HANDLED;
434 }
435
436 static int mxs_lradc_adc_configure_trigger(struct iio_trigger *trig, bool state)
437 {
438 struct iio_dev *iio = iio_trigger_get_drvdata(trig);
439 struct mxs_lradc_adc *adc = iio_priv(iio);
440 const u32 st = state ? STMP_OFFSET_REG_SET : STMP_OFFSET_REG_CLR;
441
442 writel(LRADC_DELAY_KICK, adc->base + (LRADC_DELAY(0) + st));
443
444 return 0;
445 }
446
447 static const struct iio_trigger_ops mxs_lradc_adc_trigger_ops = {
448 .set_trigger_state = &mxs_lradc_adc_configure_trigger,
449 };
450
451 static int mxs_lradc_adc_trigger_init(struct iio_dev *iio)
452 {
453 int ret;
454 struct iio_trigger *trig;
455 struct mxs_lradc_adc *adc = iio_priv(iio);
456
457 trig = devm_iio_trigger_alloc(&iio->dev, "%s-dev%i", iio->name,
458 iio->id);
459 if (!trig)
460 return -ENOMEM;
461
462 trig->dev.parent = adc->dev;
463 iio_trigger_set_drvdata(trig, iio);
464 trig->ops = &mxs_lradc_adc_trigger_ops;
465
466 ret = iio_trigger_register(trig);
467 if (ret)
468 return ret;
469
470 adc->trig = trig;
471
472 return 0;
473 }
474
475 static void mxs_lradc_adc_trigger_remove(struct iio_dev *iio)
476 {
477 struct mxs_lradc_adc *adc = iio_priv(iio);
478
479 iio_trigger_unregister(adc->trig);
480 }
481
482 static int mxs_lradc_adc_buffer_preenable(struct iio_dev *iio)
483 {
484 struct mxs_lradc_adc *adc = iio_priv(iio);
485 struct mxs_lradc *lradc = adc->lradc;
486 int chan, ofs = 0;
487 unsigned long enable = 0;
488 u32 ctrl4_set = 0;
489 u32 ctrl4_clr = 0;
490 u32 ctrl1_irq = 0;
491 const u32 chan_value = LRADC_CH_ACCUMULATE |
492 ((LRADC_DELAY_TIMER_LOOP - 1) << LRADC_CH_NUM_SAMPLES_OFFSET);
493
494 if (lradc->soc == IMX28_LRADC)
495 writel(lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
496 adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
497 writel(lradc->buffer_vchans,
498 adc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
499
500 for_each_set_bit(chan, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {
501 ctrl4_set |= chan << LRADC_CTRL4_LRADCSELECT_OFFSET(ofs);
502 ctrl4_clr |= LRADC_CTRL4_LRADCSELECT_MASK(ofs);
503 ctrl1_irq |= LRADC_CTRL1_LRADC_IRQ_EN(ofs);
504 writel(chan_value, adc->base + LRADC_CH(ofs));
505 bitmap_set(&enable, ofs, 1);
506 ofs++;
507 }
508
509 writel(LRADC_DELAY_TRIGGER_LRADCS_MASK | LRADC_DELAY_KICK,
510 adc->base + LRADC_DELAY(0) + STMP_OFFSET_REG_CLR);
511 writel(ctrl4_clr, adc->base + LRADC_CTRL4 + STMP_OFFSET_REG_CLR);
512 writel(ctrl4_set, adc->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET);
513 writel(ctrl1_irq, adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);
514 writel(enable << LRADC_DELAY_TRIGGER_LRADCS_OFFSET,
515 adc->base + LRADC_DELAY(0) + STMP_OFFSET_REG_SET);
516
517 return 0;
518 }
519
520 static int mxs_lradc_adc_buffer_postdisable(struct iio_dev *iio)
521 {
522 struct mxs_lradc_adc *adc = iio_priv(iio);
523 struct mxs_lradc *lradc = adc->lradc;
524
525 writel(LRADC_DELAY_TRIGGER_LRADCS_MASK | LRADC_DELAY_KICK,
526 adc->base + LRADC_DELAY(0) + STMP_OFFSET_REG_CLR);
527
528 writel(lradc->buffer_vchans,
529 adc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
530 if (lradc->soc == IMX28_LRADC)
531 writel(lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
532 adc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
533
534 return 0;
535 }
536
537 static bool mxs_lradc_adc_validate_scan_mask(struct iio_dev *iio,
538 const unsigned long *mask)
539 {
540 struct mxs_lradc_adc *adc = iio_priv(iio);
541 struct mxs_lradc *lradc = adc->lradc;
542 const int map_chans = bitmap_weight(mask, LRADC_MAX_TOTAL_CHANS);
543 int rsvd_chans = 0;
544 unsigned long rsvd_mask = 0;
545
546 if (lradc->use_touchbutton)
547 rsvd_mask |= CHAN_MASK_TOUCHBUTTON;
548 if (lradc->touchscreen_wire == MXS_LRADC_TOUCHSCREEN_4WIRE)
549 rsvd_mask |= CHAN_MASK_TOUCHSCREEN_4WIRE;
550 if (lradc->touchscreen_wire == MXS_LRADC_TOUCHSCREEN_5WIRE)
551 rsvd_mask |= CHAN_MASK_TOUCHSCREEN_5WIRE;
552
553 if (lradc->use_touchbutton)
554 rsvd_chans++;
555 if (lradc->touchscreen_wire)
556 rsvd_chans += 2;
557
558 /* Test for attempts to map channels with special mode of operation. */
559 if (bitmap_intersects(mask, &rsvd_mask, LRADC_MAX_TOTAL_CHANS))
560 return false;
561
562 /* Test for attempts to map more channels then available slots. */
563 if (map_chans + rsvd_chans > LRADC_MAX_MAPPED_CHANS)
564 return false;
565
566 return true;
567 }
568
569 static const struct iio_buffer_setup_ops mxs_lradc_adc_buffer_ops = {
570 .preenable = &mxs_lradc_adc_buffer_preenable,
571 .postdisable = &mxs_lradc_adc_buffer_postdisable,
572 .validate_scan_mask = &mxs_lradc_adc_validate_scan_mask,
573 };
574
575 /* Driver initialization */
576 #define MXS_ADC_CHAN(idx, chan_type, name) { \
577 .type = (chan_type), \
578 .indexed = 1, \
579 .scan_index = (idx), \
580 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
581 BIT(IIO_CHAN_INFO_SCALE), \
582 .channel = (idx), \
583 .address = (idx), \
584 .scan_type = { \
585 .sign = 'u', \
586 .realbits = LRADC_RESOLUTION, \
587 .storagebits = 32, \
588 }, \
589 .datasheet_name = (name), \
590 }
591
592 static const struct iio_chan_spec mx23_lradc_chan_spec[] = {
593 MXS_ADC_CHAN(0, IIO_VOLTAGE, "LRADC0"),
594 MXS_ADC_CHAN(1, IIO_VOLTAGE, "LRADC1"),
595 MXS_ADC_CHAN(2, IIO_VOLTAGE, "LRADC2"),
596 MXS_ADC_CHAN(3, IIO_VOLTAGE, "LRADC3"),
597 MXS_ADC_CHAN(4, IIO_VOLTAGE, "LRADC4"),
598 MXS_ADC_CHAN(5, IIO_VOLTAGE, "LRADC5"),
599 MXS_ADC_CHAN(6, IIO_VOLTAGE, "VDDIO"),
600 MXS_ADC_CHAN(7, IIO_VOLTAGE, "VBATT"),
601 /* Combined Temperature sensors */
602 {
603 .type = IIO_TEMP,
604 .indexed = 1,
605 .scan_index = 8,
606 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
607 BIT(IIO_CHAN_INFO_OFFSET) |
608 BIT(IIO_CHAN_INFO_SCALE),
609 .channel = 8,
610 .scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,},
611 .datasheet_name = "TEMP_DIE",
612 },
613 /* Hidden channel to keep indexes */
614 {
615 .type = IIO_TEMP,
616 .indexed = 1,
617 .scan_index = -1,
618 .channel = 9,
619 },
620 MXS_ADC_CHAN(10, IIO_VOLTAGE, NULL),
621 MXS_ADC_CHAN(11, IIO_VOLTAGE, NULL),
622 MXS_ADC_CHAN(12, IIO_VOLTAGE, "USB_DP"),
623 MXS_ADC_CHAN(13, IIO_VOLTAGE, "USB_DN"),
624 MXS_ADC_CHAN(14, IIO_VOLTAGE, "VBG"),
625 MXS_ADC_CHAN(15, IIO_VOLTAGE, "VDD5V"),
626 };
627
628 static const struct iio_chan_spec mx28_lradc_chan_spec[] = {
629 MXS_ADC_CHAN(0, IIO_VOLTAGE, "LRADC0"),
630 MXS_ADC_CHAN(1, IIO_VOLTAGE, "LRADC1"),
631 MXS_ADC_CHAN(2, IIO_VOLTAGE, "LRADC2"),
632 MXS_ADC_CHAN(3, IIO_VOLTAGE, "LRADC3"),
633 MXS_ADC_CHAN(4, IIO_VOLTAGE, "LRADC4"),
634 MXS_ADC_CHAN(5, IIO_VOLTAGE, "LRADC5"),
635 MXS_ADC_CHAN(6, IIO_VOLTAGE, "LRADC6"),
636 MXS_ADC_CHAN(7, IIO_VOLTAGE, "VBATT"),
637 /* Combined Temperature sensors */
638 {
639 .type = IIO_TEMP,
640 .indexed = 1,
641 .scan_index = 8,
642 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
643 BIT(IIO_CHAN_INFO_OFFSET) |
644 BIT(IIO_CHAN_INFO_SCALE),
645 .channel = 8,
646 .scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,},
647 .datasheet_name = "TEMP_DIE",
648 },
649 /* Hidden channel to keep indexes */
650 {
651 .type = IIO_TEMP,
652 .indexed = 1,
653 .scan_index = -1,
654 .channel = 9,
655 },
656 MXS_ADC_CHAN(10, IIO_VOLTAGE, "VDDIO"),
657 MXS_ADC_CHAN(11, IIO_VOLTAGE, "VTH"),
658 MXS_ADC_CHAN(12, IIO_VOLTAGE, "VDDA"),
659 MXS_ADC_CHAN(13, IIO_VOLTAGE, "VDDD"),
660 MXS_ADC_CHAN(14, IIO_VOLTAGE, "VBG"),
661 MXS_ADC_CHAN(15, IIO_VOLTAGE, "VDD5V"),
662 };
663
664 static void mxs_lradc_adc_hw_init(struct mxs_lradc_adc *adc)
665 {
666 /* The ADC always uses DELAY CHANNEL 0. */
667 const u32 adc_cfg =
668 (1 << (LRADC_DELAY_TRIGGER_DELAYS_OFFSET + 0)) |
669 (LRADC_DELAY_TIMER_PER << LRADC_DELAY_DELAY_OFFSET);
670
671 /* Configure DELAY CHANNEL 0 for generic ADC sampling. */
672 writel(adc_cfg, adc->base + LRADC_DELAY(0));
673
674 /*
675 * Start internal temperature sensing by clearing bit
676 * HW_LRADC_CTRL2_TEMPSENSE_PWD. This bit can be left cleared
677 * after power up.
678 */
679 writel(0, adc->base + LRADC_CTRL2);
680 }
681
682 static void mxs_lradc_adc_hw_stop(struct mxs_lradc_adc *adc)
683 {
684 writel(0, adc->base + LRADC_DELAY(0));
685 }
686
687 static int mxs_lradc_adc_probe(struct platform_device *pdev)
688 {
689 struct device *dev = &pdev->dev;
690 struct mxs_lradc *lradc = dev_get_drvdata(dev->parent);
691 struct mxs_lradc_adc *adc;
692 struct iio_dev *iio;
693 struct resource *iores;
694 int ret, irq, virq, i, s, n;
695 u64 scale_uv;
696 const char **irq_name;
697
698 /* Allocate the IIO device. */
699 iio = devm_iio_device_alloc(dev, sizeof(*adc));
700 if (!iio) {
701 dev_err(dev, "Failed to allocate IIO device\n");
702 return -ENOMEM;
703 }
704
705 adc = iio_priv(iio);
706 adc->lradc = lradc;
707 adc->dev = dev;
708
709 iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
710 if (!iores)
711 return -EINVAL;
712
713 adc->base = devm_ioremap(dev, iores->start, resource_size(iores));
714 if (!adc->base)
715 return -ENOMEM;
716
717 init_completion(&adc->completion);
718 spin_lock_init(&adc->lock);
719
720 platform_set_drvdata(pdev, iio);
721
722 iio->name = pdev->name;
723 iio->dev.of_node = dev->parent->of_node;
724 iio->info = &mxs_lradc_adc_iio_info;
725 iio->modes = INDIO_DIRECT_MODE;
726 iio->masklength = LRADC_MAX_TOTAL_CHANS;
727
728 if (lradc->soc == IMX23_LRADC) {
729 iio->channels = mx23_lradc_chan_spec;
730 iio->num_channels = ARRAY_SIZE(mx23_lradc_chan_spec);
731 irq_name = mx23_lradc_adc_irq_names;
732 n = ARRAY_SIZE(mx23_lradc_adc_irq_names);
733 } else {
734 iio->channels = mx28_lradc_chan_spec;
735 iio->num_channels = ARRAY_SIZE(mx28_lradc_chan_spec);
736 irq_name = mx28_lradc_adc_irq_names;
737 n = ARRAY_SIZE(mx28_lradc_adc_irq_names);
738 }
739
740 ret = stmp_reset_block(adc->base);
741 if (ret)
742 return ret;
743
744 for (i = 0; i < n; i++) {
745 irq = platform_get_irq_byname(pdev, irq_name[i]);
746 if (irq < 0)
747 return irq;
748
749 virq = irq_of_parse_and_map(dev->parent->of_node, irq);
750
751 ret = devm_request_irq(dev, virq, mxs_lradc_adc_handle_irq,
752 0, irq_name[i], iio);
753 if (ret)
754 return ret;
755 }
756
757 ret = mxs_lradc_adc_trigger_init(iio);
758 if (ret)
759 goto err_trig;
760
761 ret = iio_triggered_buffer_setup(iio, &iio_pollfunc_store_time,
762 &mxs_lradc_adc_trigger_handler,
763 &mxs_lradc_adc_buffer_ops);
764 if (ret)
765 return ret;
766
767 adc->vref_mv = mxs_lradc_adc_vref_mv[lradc->soc];
768
769 /* Populate available ADC input ranges */
770 for (i = 0; i < LRADC_MAX_TOTAL_CHANS; i++) {
771 for (s = 0; s < ARRAY_SIZE(adc->scale_avail[i]); s++) {
772 /*
773 * [s=0] = optional divider by two disabled (default)
774 * [s=1] = optional divider by two enabled
775 *
776 * The scale is calculated by doing:
777 * Vref >> (realbits - s)
778 * which multiplies by two on the second component
779 * of the array.
780 */
781 scale_uv = ((u64)adc->vref_mv[i] * 100000000) >>
782 (LRADC_RESOLUTION - s);
783 adc->scale_avail[i][s].nano =
784 do_div(scale_uv, 100000000) * 10;
785 adc->scale_avail[i][s].integer = scale_uv;
786 }
787 }
788
789 /* Configure the hardware. */
790 mxs_lradc_adc_hw_init(adc);
791
792 /* Register IIO device. */
793 ret = iio_device_register(iio);
794 if (ret) {
795 dev_err(dev, "Failed to register IIO device\n");
796 goto err_dev;
797 }
798
799 return 0;
800
801 err_dev:
802 mxs_lradc_adc_hw_stop(adc);
803 mxs_lradc_adc_trigger_remove(iio);
804 err_trig:
805 iio_triggered_buffer_cleanup(iio);
806 return ret;
807 }
808
809 static int mxs_lradc_adc_remove(struct platform_device *pdev)
810 {
811 struct iio_dev *iio = platform_get_drvdata(pdev);
812 struct mxs_lradc_adc *adc = iio_priv(iio);
813
814 iio_device_unregister(iio);
815 mxs_lradc_adc_hw_stop(adc);
816 mxs_lradc_adc_trigger_remove(iio);
817 iio_triggered_buffer_cleanup(iio);
818
819 return 0;
820 }
821
822 static struct platform_driver mxs_lradc_adc_driver = {
823 .driver = {
824 .name = "mxs-lradc-adc",
825 },
826 .probe = mxs_lradc_adc_probe,
827 .remove = mxs_lradc_adc_remove,
828 };
829 module_platform_driver(mxs_lradc_adc_driver);
830
831 MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
832 MODULE_DESCRIPTION("Freescale MXS LRADC driver general purpose ADC driver");
833 MODULE_LICENSE("GPL");
834 MODULE_ALIAS("platform:mxs-lradc-adc");
Linux with added FPC-III support