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, dir: IIO_EV_DIR_RISING) ||
148 palmas_gpadc_get_event(adc, adc_chan, dir: 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(palmas: 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(palmas: 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 val: 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(palmas: adc->palmas, PALMAS_GPADC_BASE,
201 PALMAS_GPADC_CTRL1,
202 PALMAS_GPADC_CTRL1_GPADC_FORCE, val: 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, ev_code: code, timestamp: 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(palmas: adc->palmas, PALMAS_INTERRUPT_BASE,
248 PALMAS_INT3_MASK,
249 PALMAS_INT3_MASK_GPADC_EOC_SW, val: 0);
250 else
251 ret = palmas_update_bits(palmas: 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(palmas: 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(palmas: 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(palmas: 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(palmas: adc->palmas, PALMAS_GPADC_BASE,
305 PALMAS_GPADC_SW_SELECT, value: 0);
306 if (ret < 0)
307 dev_err(adc->dev, "SW_SELECT write failed: %d\n", ret);
308
309 ret = palmas_update_bits(palmas: adc->palmas, PALMAS_GPADC_BASE,
310 PALMAS_GPADC_CTRL1,
311 PALMAS_GPADC_CTRL1_GPADC_FORCE, val: 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, enable: true);
329 if (ret < 0)
330 return ret;
331
332 return palmas_gpadc_start_mask_interrupt(adc, mask: 0);
333}
334
335static void palmas_gpadc_read_done(struct palmas_gpadc *adc, int adc_chan)
336{
337 palmas_gpadc_start_mask_interrupt(adc, mask: 1);
338 palmas_gpadc_enable(adc, adc_chan, enable: 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(palmas: adc->palmas, PALMAS_TRIM_GPADC_BASE,
354 reg: adc->adc_info[adc_chan].trim1_reg, val: &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(palmas: adc->palmas, PALMAS_TRIM_GPADC_BASE,
361 reg: adc->adc_info[adc_chan].trim2_reg, val: &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(palmas: adc->palmas, PALMAS_GPADC_BASE,
394 reg, val: &val, val_count: 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(x: &adc->conv_completion);
402 ret = palmas_update_bits(palmas: 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(x: &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(palmas: adc->palmas, PALMAS_GPADC_BASE,
419 PALMAS_GPADC_SW_CONV0_LSB, val: &val, val_count: 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 INL: max_INL,
502 gain_error: max_gain_error,
503 offset_error: 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 INL: min_INL,
537 gain_error: min_gain_error,
538 offset_error: 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, val: ret);
570
571 *val = ret;
572
573 ret = IIO_VAL_INT;
574 goto out;
575 }
576
577 mutex_unlock(lock: &adc->lock);
578 return ret;
579
580out:
581 palmas_gpadc_read_done(adc, adc_chan);
582 mutex_unlock(lock: &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(lock: &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(lock: &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(lock: &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(lock: &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(dev: &pdev->dev, size: sizeof(*gp_data), GFP_KERNEL);
840 if (!gp_data)
841 return -ENOMEM;
842
843 ret = of_property_read_u32(np, propname: "ti,channel0-current-microamp", out_value: &pval);
844 if (!ret)
845 gp_data->ch0_current = pval;
846
847 ret = of_property_read_u32(np, propname: "ti,channel3-current-microamp", out_value: &pval);
848 if (!ret)
849 gp_data->ch3_current = pval;
850
851 gp_data->extended_delay = of_property_read_bool(np,
852 propname: "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(dev: 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: &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(parent: &pdev->dev, sizeof_priv: 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(dev: pdev->dev.parent);
896 adc->adc_info = palmas_gpadc_info;
897
898 mutex_init(&adc->lock);
899
900 init_completion(x: &adc->conv_completion);
901 platform_set_drvdata(pdev, data: indio_dev);
902
903 adc->auto_conversion_period = gpadc_pdata->auto_conversion_period_ms;
904 adc->irq = palmas_irq_get_virq(palmas: adc->palmas, irq: PALMAS_GPADC_EOC_SW_IRQ);
905 if (adc->irq < 0)
906 return dev_err_probe(dev: adc->dev, err: adc->irq, fmt: "get virq failed\n");
907
908 ret = devm_request_threaded_irq(dev: &pdev->dev, irq: adc->irq, NULL,
909 thread_fn: palmas_gpadc_irq,
910 IRQF_ONESHOT, devname: dev_name(dev: adc->dev),
911 dev_id: adc);
912 if (ret < 0)
913 return dev_err_probe(dev: adc->dev, err: ret,
914 fmt: "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(dev: &pdev->dev, irq: adc->irq_auto_0, NULL,
921 thread_fn: palmas_gpadc_irq_auto, IRQF_ONESHOT,
922 devname: "palmas-adc-auto-0", dev_id: indio_dev);
923 if (ret < 0)
924 return dev_err_probe(dev: adc->dev, err: ret,
925 fmt: "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(dev: &pdev->dev, irq: adc->irq_auto_1, NULL,
933 thread_fn: palmas_gpadc_irq_auto, IRQF_ONESHOT,
934 devname: "palmas-adc-auto-1", dev_id: indio_dev);
935 if (ret < 0)
936 return dev_err_probe(dev: adc->dev, err: ret,
937 fmt: "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(dev: adc->dev, err: ret,
978 fmt: "iio_device_register() failed\n");
979
980 device_set_wakeup_capable(dev: &pdev->dev, capable: 1);
981 for (i = 0; i < PALMAS_ADC_CH_MAX; i++) {
982 if (!(adc->adc_info[i].is_uncalibrated))
983 palmas_gpadc_calibrate(adc, adc_chan: 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(palmas: adc->palmas, PALMAS_GPADC_BASE,
1010 PALMAS_GPADC_AUTO_CTRL,
1011 PALMAS_GPADC_AUTO_CTRL_COUNTER_CONV_MASK,
1012 val: 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(palmas: adc->palmas, PALMAS_GPADC_BASE,
1039 PALMAS_GPADC_THRES_CONV0_LSB, value: 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(palmas: adc->palmas, PALMAS_GPADC_BASE,
1047 PALMAS_GPADC_THRES_CONV0_MSB,
1048 value: ((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(palmas: adc->palmas, PALMAS_GPADC_BASE,
1076 PALMAS_GPADC_THRES_CONV1_LSB, value: 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(palmas: adc->palmas, PALMAS_GPADC_BASE,
1084 PALMAS_GPADC_THRES_CONV1_MSB,
1085 value: ((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(palmas: adc->palmas, PALMAS_GPADC_BASE,
1094 PALMAS_GPADC_AUTO_SELECT, value: (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(palmas: 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, val: 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(palmas: adc->palmas, PALMAS_GPADC_BASE,
1115 PALMAS_GPADC_AUTO_SELECT, value: 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(irq: adc->irq_auto_0);
1138
1139 if (adc->event1.enabled)
1140 enable_irq_wake(irq: 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(irq: adc->irq_auto_0);
1155
1156 if (adc->event1.enabled)
1157 disable_irq_wake(irq: 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

source code of linux/drivers/iio/adc/palmas_gpadc.c