xref: /openbmc/linux/drivers/iio/adc/twl6030-gpadc.c (revision fcbd8037)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * TWL6030 GPADC module driver
4  *
5  * Copyright (C) 2009-2013 Texas Instruments Inc.
6  * Nishant Kamat <nskamat@ti.com>
7  * Balaji T K <balajitk@ti.com>
8  * Graeme Gregory <gg@slimlogic.co.uk>
9  * Girish S Ghongdemath <girishsg@ti.com>
10  * Ambresh K <ambresh@ti.com>
11  * Oleksandr Kozaruk <oleksandr.kozaruk@ti.com
12  *
13  * Based on twl4030-madc.c
14  * Copyright (C) 2008 Nokia Corporation
15  * Mikko Ylinen <mikko.k.ylinen@nokia.com>
16  */
17 #include <linux/interrupt.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/of_platform.h>
22 #include <linux/mfd/twl.h>
23 #include <linux/iio/iio.h>
24 #include <linux/iio/sysfs.h>
25 
26 #define DRIVER_NAME		"twl6030_gpadc"
27 
28 /*
29  * twl6030 per TRM has 17 channels, and twl6032 has 19 channels
30  * 2 test network channels are not used,
31  * 2 die temperature channels are not used either, as it is not
32  * defined how to convert ADC value to temperature
33  */
34 #define TWL6030_GPADC_USED_CHANNELS		13
35 #define TWL6030_GPADC_MAX_CHANNELS		15
36 #define TWL6032_GPADC_USED_CHANNELS		15
37 #define TWL6032_GPADC_MAX_CHANNELS		19
38 #define TWL6030_GPADC_NUM_TRIM_REGS		16
39 
40 #define TWL6030_GPADC_CTRL_P1			0x05
41 
42 #define TWL6032_GPADC_GPSELECT_ISB		0x07
43 #define TWL6032_GPADC_CTRL_P1			0x08
44 
45 #define TWL6032_GPADC_GPCH0_LSB			0x0d
46 #define TWL6032_GPADC_GPCH0_MSB			0x0e
47 
48 #define TWL6030_GPADC_CTRL_P1_SP1		BIT(3)
49 
50 #define TWL6030_GPADC_GPCH0_LSB			(0x29)
51 
52 #define TWL6030_GPADC_RT_SW1_EOC_MASK		BIT(5)
53 
54 #define TWL6030_GPADC_TRIM1			0xCD
55 
56 #define TWL6030_REG_TOGGLE1			0x90
57 #define TWL6030_GPADCS				BIT(1)
58 #define TWL6030_GPADCR				BIT(0)
59 
60 /**
61  * struct twl6030_chnl_calib - channel calibration
62  * @gain:		slope coefficient for ideal curve
63  * @gain_error:		gain error
64  * @offset_error:	offset of the real curve
65  */
66 struct twl6030_chnl_calib {
67 	s32 gain;
68 	s32 gain_error;
69 	s32 offset_error;
70 };
71 
72 /**
73  * struct twl6030_ideal_code - GPADC calibration parameters
74  * GPADC is calibrated in two points: close to the beginning and
75  * to the and of the measurable input range
76  *
77  * @channel:	channel number
78  * @code1:	ideal code for the input at the beginning
79  * @code2:	ideal code for at the end of the range
80  * @volt1:	voltage input at the beginning(low voltage)
81  * @volt2:	voltage input at the end(high voltage)
82  */
83 struct twl6030_ideal_code {
84 	int channel;
85 	u16 code1;
86 	u16 code2;
87 	u16 volt1;
88 	u16 volt2;
89 };
90 
91 struct twl6030_gpadc_data;
92 
93 /**
94  * struct twl6030_gpadc_platform_data - platform specific data
95  * @nchannels:		number of GPADC channels
96  * @iio_channels:	iio channels
97  * @twl6030_ideal:	pointer to calibration parameters
98  * @start_conversion:	pointer to ADC start conversion function
99  * @channel_to_reg	pointer to ADC function to convert channel to
100  *			register address for reading conversion result
101  * @calibrate:		pointer to calibration function
102  */
103 struct twl6030_gpadc_platform_data {
104 	const int nchannels;
105 	const struct iio_chan_spec *iio_channels;
106 	const struct twl6030_ideal_code *ideal;
107 	int (*start_conversion)(int channel);
108 	u8 (*channel_to_reg)(int channel);
109 	int (*calibrate)(struct twl6030_gpadc_data *gpadc);
110 };
111 
112 /**
113  * struct twl6030_gpadc_data - GPADC data
114  * @dev:		device pointer
115  * @lock:		mutual exclusion lock for the structure
116  * @irq_complete:	completion to signal end of conversion
117  * @twl6030_cal_tbl:	pointer to calibration data for each
118  *			channel with gain error and offset
119  * @pdata:		pointer to device specific data
120  */
121 struct twl6030_gpadc_data {
122 	struct device	*dev;
123 	struct mutex	lock;
124 	struct completion	irq_complete;
125 	struct twl6030_chnl_calib	*twl6030_cal_tbl;
126 	const struct twl6030_gpadc_platform_data *pdata;
127 };
128 
129 /*
130  * channels 11, 12, 13, 15 and 16 have no calibration data
131  * calibration offset is same for channels 1, 3, 4, 5
132  *
133  * The data is taken from GPADC_TRIM registers description.
134  * GPADC_TRIM registers keep difference between the code measured
135  * at volt1 and volt2 input voltages and corresponding code1 and code2
136  */
137 static const struct twl6030_ideal_code
138 	twl6030_ideal[TWL6030_GPADC_USED_CHANNELS] = {
139 	[0] = { /* ch 0, external, battery type, resistor value */
140 		.channel = 0,
141 		.code1 = 116,
142 		.code2 = 745,
143 		.volt1 = 141,
144 		.volt2 = 910,
145 	},
146 	[1] = { /* ch 1, external, battery temperature, NTC resistor value */
147 		.channel = 1,
148 		.code1 = 82,
149 		.code2 = 900,
150 		.volt1 = 100,
151 		.volt2 = 1100,
152 	},
153 	[2] = { /* ch 2, external, audio accessory/general purpose */
154 		.channel = 2,
155 		.code1 = 55,
156 		.code2 = 818,
157 		.volt1 = 101,
158 		.volt2 = 1499,
159 	},
160 	[3] = { /* ch 3, external, general purpose */
161 		.channel = 3,
162 		.code1 = 82,
163 		.code2 = 900,
164 		.volt1 = 100,
165 		.volt2 = 1100,
166 	},
167 	[4] = { /* ch 4, external, temperature measurement/general purpose */
168 		.channel = 4,
169 		.code1 = 82,
170 		.code2 = 900,
171 		.volt1 = 100,
172 		.volt2 = 1100,
173 	},
174 	[5] = { /* ch 5, external, general purpose */
175 		.channel = 5,
176 		.code1 = 82,
177 		.code2 = 900,
178 		.volt1 = 100,
179 		.volt2 = 1100,
180 	},
181 	[6] = { /* ch 6, external, general purpose */
182 		.channel = 6,
183 		.code1 = 82,
184 		.code2 = 900,
185 		.volt1 = 100,
186 		.volt2 = 1100,
187 	},
188 	[7] = { /* ch 7, internal, main battery */
189 		.channel = 7,
190 		.code1 = 614,
191 		.code2 = 941,
192 		.volt1 = 3001,
193 		.volt2 = 4599,
194 	},
195 	[8] = { /* ch 8, internal, backup battery */
196 		.channel = 8,
197 		.code1 = 82,
198 		.code2 = 688,
199 		.volt1 = 501,
200 		.volt2 = 4203,
201 	},
202 	[9] = { /* ch 9, internal, external charger input */
203 		.channel = 9,
204 		.code1 = 182,
205 		.code2 = 818,
206 		.volt1 = 2001,
207 		.volt2 = 8996,
208 	},
209 	[10] = { /* ch 10, internal, VBUS */
210 		.channel = 10,
211 		.code1 = 149,
212 		.code2 = 818,
213 		.volt1 = 1001,
214 		.volt2 = 5497,
215 	},
216 	[11] = { /* ch 11, internal, VBUS charging current */
217 		.channel = 11,
218 	},
219 		/* ch 12, internal, Die temperature */
220 		/* ch 13, internal, Die temperature */
221 	[12] = { /* ch 14, internal, USB ID line */
222 		.channel = 14,
223 		.code1 = 48,
224 		.code2 = 714,
225 		.volt1 = 323,
226 		.volt2 = 4800,
227 	},
228 };
229 
230 static const struct twl6030_ideal_code
231 			twl6032_ideal[TWL6032_GPADC_USED_CHANNELS] = {
232 	[0] = { /* ch 0, external, battery type, resistor value */
233 		.channel = 0,
234 		.code1 = 1441,
235 		.code2 = 3276,
236 		.volt1 = 440,
237 		.volt2 = 1000,
238 	},
239 	[1] = { /* ch 1, external, battery temperature, NTC resistor value */
240 		.channel = 1,
241 		.code1 = 1441,
242 		.code2 = 3276,
243 		.volt1 = 440,
244 		.volt2 = 1000,
245 	},
246 	[2] = { /* ch 2, external, audio accessory/general purpose */
247 		.channel = 2,
248 		.code1 = 1441,
249 		.code2 = 3276,
250 		.volt1 = 660,
251 		.volt2 = 1500,
252 	},
253 	[3] = { /* ch 3, external, temperature with external diode/general
254 								purpose */
255 		.channel = 3,
256 		.code1 = 1441,
257 		.code2 = 3276,
258 		.volt1 = 440,
259 		.volt2 = 1000,
260 	},
261 	[4] = { /* ch 4, external, temperature measurement/general purpose */
262 		.channel = 4,
263 		.code1 = 1441,
264 		.code2 = 3276,
265 		.volt1 = 440,
266 		.volt2 = 1000,
267 	},
268 	[5] = { /* ch 5, external, general purpose */
269 		.channel = 5,
270 		.code1 = 1441,
271 		.code2 = 3276,
272 		.volt1 = 440,
273 		.volt2 = 1000,
274 	},
275 	[6] = { /* ch 6, external, general purpose */
276 		.channel = 6,
277 		.code1 = 1441,
278 		.code2 = 3276,
279 		.volt1 = 440,
280 		.volt2 = 1000,
281 	},
282 	[7] = { /* ch7, internal, system supply */
283 		.channel = 7,
284 		.code1 = 1441,
285 		.code2 = 3276,
286 		.volt1 = 2200,
287 		.volt2 = 5000,
288 	},
289 	[8] = { /* ch8, internal, backup battery */
290 		.channel = 8,
291 		.code1 = 1441,
292 		.code2 = 3276,
293 		.volt1 = 2200,
294 		.volt2 = 5000,
295 	},
296 	[9] = { /* ch 9, internal, external charger input */
297 		.channel = 9,
298 		.code1 = 1441,
299 		.code2 = 3276,
300 		.volt1 = 3960,
301 		.volt2 = 9000,
302 	},
303 	[10] = { /* ch10, internal, VBUS */
304 		.channel = 10,
305 		.code1 = 150,
306 		.code2 = 751,
307 		.volt1 = 1000,
308 		.volt2 = 5000,
309 	},
310 	[11] = { /* ch 11, internal, VBUS DC-DC output current */
311 		.channel = 11,
312 		.code1 = 1441,
313 		.code2 = 3276,
314 		.volt1 = 660,
315 		.volt2 = 1500,
316 	},
317 		/* ch 12, internal, Die temperature */
318 		/* ch 13, internal, Die temperature */
319 	[12] = { /* ch 14, internal, USB ID line */
320 		.channel = 14,
321 		.code1 = 1441,
322 		.code2 = 3276,
323 		.volt1 = 2420,
324 		.volt2 = 5500,
325 	},
326 		/* ch 15, internal, test network */
327 		/* ch 16, internal, test network */
328 	[13] = { /* ch 17, internal, battery charging current */
329 		.channel = 17,
330 	},
331 	[14] = { /* ch 18, internal, battery voltage */
332 		.channel = 18,
333 		.code1 = 1441,
334 		.code2 = 3276,
335 		.volt1 = 2200,
336 		.volt2 = 5000,
337 	},
338 };
339 
340 static inline int twl6030_gpadc_write(u8 reg, u8 val)
341 {
342 	return twl_i2c_write_u8(TWL6030_MODULE_GPADC, val, reg);
343 }
344 
345 static inline int twl6030_gpadc_read(u8 reg, u8 *val)
346 {
347 
348 	return twl_i2c_read(TWL6030_MODULE_GPADC, val, reg, 2);
349 }
350 
351 static int twl6030_gpadc_enable_irq(u8 mask)
352 {
353 	int ret;
354 
355 	ret = twl6030_interrupt_unmask(mask, REG_INT_MSK_LINE_B);
356 	if (ret < 0)
357 		return ret;
358 
359 	ret = twl6030_interrupt_unmask(mask, REG_INT_MSK_STS_B);
360 
361 	return ret;
362 }
363 
364 static void twl6030_gpadc_disable_irq(u8 mask)
365 {
366 	twl6030_interrupt_mask(mask, REG_INT_MSK_LINE_B);
367 	twl6030_interrupt_mask(mask, REG_INT_MSK_STS_B);
368 }
369 
370 static irqreturn_t twl6030_gpadc_irq_handler(int irq, void *indio_dev)
371 {
372 	struct twl6030_gpadc_data *gpadc = iio_priv(indio_dev);
373 
374 	complete(&gpadc->irq_complete);
375 
376 	return IRQ_HANDLED;
377 }
378 
379 static int twl6030_start_conversion(int channel)
380 {
381 	return twl6030_gpadc_write(TWL6030_GPADC_CTRL_P1,
382 					TWL6030_GPADC_CTRL_P1_SP1);
383 }
384 
385 static int twl6032_start_conversion(int channel)
386 {
387 	int ret;
388 
389 	ret = twl6030_gpadc_write(TWL6032_GPADC_GPSELECT_ISB, channel);
390 	if (ret)
391 		return ret;
392 
393 	return twl6030_gpadc_write(TWL6032_GPADC_CTRL_P1,
394 						TWL6030_GPADC_CTRL_P1_SP1);
395 }
396 
397 static u8 twl6030_channel_to_reg(int channel)
398 {
399 	return TWL6030_GPADC_GPCH0_LSB + 2 * channel;
400 }
401 
402 static u8 twl6032_channel_to_reg(int channel)
403 {
404 	/*
405 	 * for any prior chosen channel, when the conversion is ready
406 	 * the result is avalable in GPCH0_LSB, GPCH0_MSB.
407 	 */
408 
409 	return TWL6032_GPADC_GPCH0_LSB;
410 }
411 
412 static int twl6030_gpadc_lookup(const struct twl6030_ideal_code *ideal,
413 		int channel, int size)
414 {
415 	int i;
416 
417 	for (i = 0; i < size; i++)
418 		if (ideal[i].channel == channel)
419 			break;
420 
421 	return i;
422 }
423 
424 static int twl6030_channel_calibrated(const struct twl6030_gpadc_platform_data
425 		*pdata, int channel)
426 {
427 	const struct twl6030_ideal_code *ideal = pdata->ideal;
428 	int i;
429 
430 	i = twl6030_gpadc_lookup(ideal, channel, pdata->nchannels);
431 	/* not calibrated channels have 0 in all structure members */
432 	return pdata->ideal[i].code2;
433 }
434 
435 static int twl6030_gpadc_make_correction(struct twl6030_gpadc_data *gpadc,
436 		int channel, int raw_code)
437 {
438 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
439 	int corrected_code;
440 	int i;
441 
442 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
443 	corrected_code = ((raw_code * 1000) -
444 		gpadc->twl6030_cal_tbl[i].offset_error) /
445 		gpadc->twl6030_cal_tbl[i].gain_error;
446 
447 	return corrected_code;
448 }
449 
450 static int twl6030_gpadc_get_raw(struct twl6030_gpadc_data *gpadc,
451 		int channel, int *res)
452 {
453 	u8 reg = gpadc->pdata->channel_to_reg(channel);
454 	__le16 val;
455 	int raw_code;
456 	int ret;
457 
458 	ret = twl6030_gpadc_read(reg, (u8 *)&val);
459 	if (ret) {
460 		dev_dbg(gpadc->dev, "unable to read register 0x%X\n", reg);
461 		return ret;
462 	}
463 
464 	raw_code = le16_to_cpu(val);
465 	dev_dbg(gpadc->dev, "GPADC raw code: %d", raw_code);
466 
467 	if (twl6030_channel_calibrated(gpadc->pdata, channel))
468 		*res = twl6030_gpadc_make_correction(gpadc, channel, raw_code);
469 	else
470 		*res = raw_code;
471 
472 	return ret;
473 }
474 
475 static int twl6030_gpadc_get_processed(struct twl6030_gpadc_data *gpadc,
476 		int channel, int *val)
477 {
478 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
479 	int corrected_code;
480 	int channel_value;
481 	int i;
482 	int ret;
483 
484 	ret = twl6030_gpadc_get_raw(gpadc, channel, &corrected_code);
485 	if (ret)
486 		return ret;
487 
488 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
489 	channel_value = corrected_code *
490 			gpadc->twl6030_cal_tbl[i].gain;
491 
492 	/* Shift back into mV range */
493 	channel_value /= 1000;
494 
495 	dev_dbg(gpadc->dev, "GPADC corrected code: %d", corrected_code);
496 	dev_dbg(gpadc->dev, "GPADC value: %d", channel_value);
497 
498 	*val = channel_value;
499 
500 	return ret;
501 }
502 
503 static int twl6030_gpadc_read_raw(struct iio_dev *indio_dev,
504 			     const struct iio_chan_spec *chan,
505 			     int *val, int *val2, long mask)
506 {
507 	struct twl6030_gpadc_data *gpadc = iio_priv(indio_dev);
508 	int ret;
509 	long timeout;
510 
511 	mutex_lock(&gpadc->lock);
512 
513 	ret = gpadc->pdata->start_conversion(chan->channel);
514 	if (ret) {
515 		dev_err(gpadc->dev, "failed to start conversion\n");
516 		goto err;
517 	}
518 	/* wait for conversion to complete */
519 	timeout = wait_for_completion_interruptible_timeout(
520 				&gpadc->irq_complete, msecs_to_jiffies(5000));
521 	if (timeout == 0) {
522 		ret = -ETIMEDOUT;
523 		goto err;
524 	} else if (timeout < 0) {
525 		ret = -EINTR;
526 		goto err;
527 	}
528 
529 	switch (mask) {
530 	case IIO_CHAN_INFO_RAW:
531 		ret = twl6030_gpadc_get_raw(gpadc, chan->channel, val);
532 		ret = ret ? -EIO : IIO_VAL_INT;
533 		break;
534 
535 	case IIO_CHAN_INFO_PROCESSED:
536 		ret = twl6030_gpadc_get_processed(gpadc, chan->channel, val);
537 		ret = ret ? -EIO : IIO_VAL_INT;
538 		break;
539 
540 	default:
541 		break;
542 	}
543 err:
544 	mutex_unlock(&gpadc->lock);
545 
546 	return ret;
547 }
548 
549 /*
550  * The GPADC channels are calibrated using a two point calibration method.
551  * The channels measured with two known values: volt1 and volt2, and
552  * ideal corresponding output codes are known: code1, code2.
553  * The difference(d1, d2) between ideal and measured codes stored in trim
554  * registers.
555  * The goal is to find offset and gain of the real curve for each calibrated
556  * channel.
557  * gain: k = 1 + ((d2 - d1) / (x2 - x1))
558  * offset: b = d1 + (k - 1) * x1
559  */
560 static void twl6030_calibrate_channel(struct twl6030_gpadc_data *gpadc,
561 		int channel, int d1, int d2)
562 {
563 	int b, k, gain, x1, x2, i;
564 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
565 
566 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
567 
568 	/* Gain */
569 	gain = ((ideal[i].volt2 - ideal[i].volt1) * 1000) /
570 		(ideal[i].code2 - ideal[i].code1);
571 
572 	x1 = ideal[i].code1;
573 	x2 = ideal[i].code2;
574 
575 	/* k - real curve gain */
576 	k = 1000 + (((d2 - d1) * 1000) / (x2 - x1));
577 
578 	/* b - offset of the real curve gain */
579 	b = (d1 * 1000) - (k - 1000) * x1;
580 
581 	gpadc->twl6030_cal_tbl[i].gain = gain;
582 	gpadc->twl6030_cal_tbl[i].gain_error = k;
583 	gpadc->twl6030_cal_tbl[i].offset_error = b;
584 
585 	dev_dbg(gpadc->dev, "GPADC d1   for Chn: %d = %d\n", channel, d1);
586 	dev_dbg(gpadc->dev, "GPADC d2   for Chn: %d = %d\n", channel, d2);
587 	dev_dbg(gpadc->dev, "GPADC x1   for Chn: %d = %d\n", channel, x1);
588 	dev_dbg(gpadc->dev, "GPADC x2   for Chn: %d = %d\n", channel, x2);
589 	dev_dbg(gpadc->dev, "GPADC Gain for Chn: %d = %d\n", channel, gain);
590 	dev_dbg(gpadc->dev, "GPADC k    for Chn: %d = %d\n", channel, k);
591 	dev_dbg(gpadc->dev, "GPADC b    for Chn: %d = %d\n", channel, b);
592 }
593 
594 static inline int twl6030_gpadc_get_trim_offset(s8 d)
595 {
596 	/*
597 	 * XXX NOTE!
598 	 * bit 0 - sign, bit 7 - reserved, 6..1 - trim value
599 	 * though, the documentation states that trim value
600 	 * is absolute value, the correct conversion results are
601 	 * obtained if the value is interpreted as 2's complement.
602 	 */
603 	__u32 temp = ((d & 0x7f) >> 1) | ((d & 1) << 6);
604 
605 	return sign_extend32(temp, 6);
606 }
607 
608 static int twl6030_calibration(struct twl6030_gpadc_data *gpadc)
609 {
610 	int ret;
611 	int chn;
612 	u8 trim_regs[TWL6030_GPADC_NUM_TRIM_REGS];
613 	s8 d1, d2;
614 
615 	/*
616 	 * for calibration two measurements have been performed at
617 	 * factory, for some channels, during the production test and
618 	 * have been stored in registers. This two stored values are
619 	 * used to correct the measurements. The values represent
620 	 * offsets for the given input from the output on ideal curve.
621 	 */
622 	ret = twl_i2c_read(TWL6030_MODULE_ID2, trim_regs,
623 			TWL6030_GPADC_TRIM1, TWL6030_GPADC_NUM_TRIM_REGS);
624 	if (ret < 0) {
625 		dev_err(gpadc->dev, "calibration failed\n");
626 		return ret;
627 	}
628 
629 	for (chn = 0; chn < TWL6030_GPADC_MAX_CHANNELS; chn++) {
630 
631 		switch (chn) {
632 		case 0:
633 			d1 = trim_regs[0];
634 			d2 = trim_regs[1];
635 			break;
636 		case 1:
637 		case 3:
638 		case 4:
639 		case 5:
640 		case 6:
641 			d1 = trim_regs[4];
642 			d2 = trim_regs[5];
643 			break;
644 		case 2:
645 			d1 = trim_regs[12];
646 			d2 = trim_regs[13];
647 			break;
648 		case 7:
649 			d1 = trim_regs[6];
650 			d2 = trim_regs[7];
651 			break;
652 		case 8:
653 			d1 = trim_regs[2];
654 			d2 = trim_regs[3];
655 			break;
656 		case 9:
657 			d1 = trim_regs[8];
658 			d2 = trim_regs[9];
659 			break;
660 		case 10:
661 			d1 = trim_regs[10];
662 			d2 = trim_regs[11];
663 			break;
664 		case 14:
665 			d1 = trim_regs[14];
666 			d2 = trim_regs[15];
667 			break;
668 		default:
669 			continue;
670 		}
671 
672 		d1 = twl6030_gpadc_get_trim_offset(d1);
673 		d2 = twl6030_gpadc_get_trim_offset(d2);
674 
675 		twl6030_calibrate_channel(gpadc, chn, d1, d2);
676 	}
677 
678 	return 0;
679 }
680 
681 static int twl6032_get_trim_value(u8 *trim_regs, unsigned int reg0,
682 		unsigned int reg1, unsigned int mask0, unsigned int mask1,
683 		unsigned int shift0)
684 {
685 	int val;
686 
687 	val = (trim_regs[reg0] & mask0) << shift0;
688 	val |= (trim_regs[reg1] & mask1) >> 1;
689 	if (trim_regs[reg1] & 0x01)
690 		val = -val;
691 
692 	return val;
693 }
694 
695 static int twl6032_calibration(struct twl6030_gpadc_data *gpadc)
696 {
697 	int chn, d1 = 0, d2 = 0, temp;
698 	u8 trim_regs[TWL6030_GPADC_NUM_TRIM_REGS];
699 	int ret;
700 
701 	ret = twl_i2c_read(TWL6030_MODULE_ID2, trim_regs,
702 			TWL6030_GPADC_TRIM1, TWL6030_GPADC_NUM_TRIM_REGS);
703 	if (ret < 0) {
704 		dev_err(gpadc->dev, "calibration failed\n");
705 		return ret;
706 	}
707 
708 	/*
709 	 * Loop to calculate the value needed for returning voltages from
710 	 * GPADC not values.
711 	 *
712 	 * gain is calculated to 3 decimal places fixed point.
713 	 */
714 	for (chn = 0; chn < TWL6032_GPADC_MAX_CHANNELS; chn++) {
715 
716 		switch (chn) {
717 		case 0:
718 		case 1:
719 		case 2:
720 		case 3:
721 		case 4:
722 		case 5:
723 		case 6:
724 		case 11:
725 		case 14:
726 			d1 = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
727 								0x06, 2);
728 			d2 = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
729 								0x06, 2);
730 			break;
731 		case 8:
732 			temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
733 								0x06, 2);
734 			d1 = temp + twl6032_get_trim_value(trim_regs, 7, 6,
735 								0x18, 0x1E, 1);
736 
737 			temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3F,
738 								0x06, 2);
739 			d2 = temp + twl6032_get_trim_value(trim_regs, 9, 7,
740 								0x1F, 0x06, 2);
741 			break;
742 		case 9:
743 			temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
744 								0x06, 2);
745 			d1 = temp + twl6032_get_trim_value(trim_regs, 13, 11,
746 								0x18, 0x1E, 1);
747 
748 			temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
749 								0x06, 2);
750 			d2 = temp + twl6032_get_trim_value(trim_regs, 15, 13,
751 								0x1F, 0x06, 1);
752 			break;
753 		case 10:
754 			d1 = twl6032_get_trim_value(trim_regs, 10, 8, 0x0f,
755 								0x0E, 3);
756 			d2 = twl6032_get_trim_value(trim_regs, 14, 12, 0x0f,
757 								0x0E, 3);
758 			break;
759 		case 7:
760 		case 18:
761 			temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
762 								0x06, 2);
763 
764 			d1 = (trim_regs[4] & 0x7E) >> 1;
765 			if (trim_regs[4] & 0x01)
766 				d1 = -d1;
767 			d1 += temp;
768 
769 			temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
770 								0x06, 2);
771 
772 			d2 = (trim_regs[5] & 0xFE) >> 1;
773 			if (trim_regs[5] & 0x01)
774 				d2 = -d2;
775 
776 			d2 += temp;
777 			break;
778 		default:
779 			/* No data for other channels */
780 			continue;
781 		}
782 
783 		twl6030_calibrate_channel(gpadc, chn, d1, d2);
784 	}
785 
786 	return 0;
787 }
788 
789 #define TWL6030_GPADC_CHAN(chn, _type, chan_info) {	\
790 	.type = _type,					\
791 	.channel = chn,					\
792 	.info_mask_separate = BIT(chan_info),		\
793 	.indexed = 1,					\
794 }
795 
796 static const struct iio_chan_spec twl6030_gpadc_iio_channels[] = {
797 	TWL6030_GPADC_CHAN(0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
798 	TWL6030_GPADC_CHAN(1, IIO_TEMP, IIO_CHAN_INFO_RAW),
799 	TWL6030_GPADC_CHAN(2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
800 	TWL6030_GPADC_CHAN(3, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
801 	TWL6030_GPADC_CHAN(4, IIO_TEMP, IIO_CHAN_INFO_RAW),
802 	TWL6030_GPADC_CHAN(5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
803 	TWL6030_GPADC_CHAN(6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
804 	TWL6030_GPADC_CHAN(7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
805 	TWL6030_GPADC_CHAN(8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
806 	TWL6030_GPADC_CHAN(9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
807 	TWL6030_GPADC_CHAN(10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
808 	TWL6030_GPADC_CHAN(11, IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
809 	TWL6030_GPADC_CHAN(14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
810 };
811 
812 static const struct iio_chan_spec twl6032_gpadc_iio_channels[] = {
813 	TWL6030_GPADC_CHAN(0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
814 	TWL6030_GPADC_CHAN(1, IIO_TEMP, IIO_CHAN_INFO_RAW),
815 	TWL6030_GPADC_CHAN(2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
816 	TWL6030_GPADC_CHAN(3, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
817 	TWL6030_GPADC_CHAN(4, IIO_TEMP, IIO_CHAN_INFO_RAW),
818 	TWL6030_GPADC_CHAN(5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
819 	TWL6030_GPADC_CHAN(6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
820 	TWL6030_GPADC_CHAN(7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
821 	TWL6030_GPADC_CHAN(8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
822 	TWL6030_GPADC_CHAN(9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
823 	TWL6030_GPADC_CHAN(10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
824 	TWL6030_GPADC_CHAN(11, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
825 	TWL6030_GPADC_CHAN(14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
826 	TWL6030_GPADC_CHAN(17, IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
827 	TWL6030_GPADC_CHAN(18, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
828 };
829 
830 static const struct iio_info twl6030_gpadc_iio_info = {
831 	.read_raw = &twl6030_gpadc_read_raw,
832 };
833 
834 static const struct twl6030_gpadc_platform_data twl6030_pdata = {
835 	.iio_channels = twl6030_gpadc_iio_channels,
836 	.nchannels = TWL6030_GPADC_USED_CHANNELS,
837 	.ideal = twl6030_ideal,
838 	.start_conversion = twl6030_start_conversion,
839 	.channel_to_reg = twl6030_channel_to_reg,
840 	.calibrate = twl6030_calibration,
841 };
842 
843 static const struct twl6030_gpadc_platform_data twl6032_pdata = {
844 	.iio_channels = twl6032_gpadc_iio_channels,
845 	.nchannels = TWL6032_GPADC_USED_CHANNELS,
846 	.ideal = twl6032_ideal,
847 	.start_conversion = twl6032_start_conversion,
848 	.channel_to_reg = twl6032_channel_to_reg,
849 	.calibrate = twl6032_calibration,
850 };
851 
852 static const struct of_device_id of_twl6030_match_tbl[] = {
853 	{
854 		.compatible = "ti,twl6030-gpadc",
855 		.data = &twl6030_pdata,
856 	},
857 	{
858 		.compatible = "ti,twl6032-gpadc",
859 		.data = &twl6032_pdata,
860 	},
861 	{ /* end */ }
862 };
863 MODULE_DEVICE_TABLE(of, of_twl6030_match_tbl);
864 
865 static int twl6030_gpadc_probe(struct platform_device *pdev)
866 {
867 	struct device *dev = &pdev->dev;
868 	struct twl6030_gpadc_data *gpadc;
869 	const struct twl6030_gpadc_platform_data *pdata;
870 	const struct of_device_id *match;
871 	struct iio_dev *indio_dev;
872 	int irq;
873 	int ret;
874 
875 	match = of_match_device(of_twl6030_match_tbl, dev);
876 	if (!match)
877 		return -EINVAL;
878 
879 	pdata = match->data;
880 
881 	indio_dev = devm_iio_device_alloc(dev, sizeof(*gpadc));
882 	if (!indio_dev)
883 		return -ENOMEM;
884 
885 	gpadc = iio_priv(indio_dev);
886 
887 	gpadc->twl6030_cal_tbl = devm_kcalloc(dev,
888 					pdata->nchannels,
889 					sizeof(*gpadc->twl6030_cal_tbl),
890 					GFP_KERNEL);
891 	if (!gpadc->twl6030_cal_tbl)
892 		return -ENOMEM;
893 
894 	gpadc->dev = dev;
895 	gpadc->pdata = pdata;
896 
897 	platform_set_drvdata(pdev, indio_dev);
898 	mutex_init(&gpadc->lock);
899 	init_completion(&gpadc->irq_complete);
900 
901 	ret = pdata->calibrate(gpadc);
902 	if (ret < 0) {
903 		dev_err(&pdev->dev, "failed to read calibration registers\n");
904 		return ret;
905 	}
906 
907 	irq = platform_get_irq(pdev, 0);
908 	if (irq < 0)
909 		return irq;
910 
911 	ret = devm_request_threaded_irq(dev, irq, NULL,
912 				twl6030_gpadc_irq_handler,
913 				IRQF_ONESHOT, "twl6030_gpadc", indio_dev);
914 
915 	ret = twl6030_gpadc_enable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK);
916 	if (ret < 0) {
917 		dev_err(&pdev->dev, "failed to enable GPADC interrupt\n");
918 		return ret;
919 	}
920 
921 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS,
922 					TWL6030_REG_TOGGLE1);
923 	if (ret < 0) {
924 		dev_err(&pdev->dev, "failed to enable GPADC module\n");
925 		return ret;
926 	}
927 
928 	indio_dev->name = DRIVER_NAME;
929 	indio_dev->dev.parent = dev;
930 	indio_dev->info = &twl6030_gpadc_iio_info;
931 	indio_dev->modes = INDIO_DIRECT_MODE;
932 	indio_dev->channels = pdata->iio_channels;
933 	indio_dev->num_channels = pdata->nchannels;
934 
935 	return iio_device_register(indio_dev);
936 }
937 
938 static int twl6030_gpadc_remove(struct platform_device *pdev)
939 {
940 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
941 
942 	twl6030_gpadc_disable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK);
943 	iio_device_unregister(indio_dev);
944 
945 	return 0;
946 }
947 
948 #ifdef CONFIG_PM_SLEEP
949 static int twl6030_gpadc_suspend(struct device *pdev)
950 {
951 	int ret;
952 
953 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCR,
954 				TWL6030_REG_TOGGLE1);
955 	if (ret)
956 		dev_err(pdev, "error resetting GPADC (%d)!\n", ret);
957 
958 	return 0;
959 };
960 
961 static int twl6030_gpadc_resume(struct device *pdev)
962 {
963 	int ret;
964 
965 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS,
966 				TWL6030_REG_TOGGLE1);
967 	if (ret)
968 		dev_err(pdev, "error setting GPADC (%d)!\n", ret);
969 
970 	return 0;
971 };
972 #endif
973 
974 static SIMPLE_DEV_PM_OPS(twl6030_gpadc_pm_ops, twl6030_gpadc_suspend,
975 					twl6030_gpadc_resume);
976 
977 static struct platform_driver twl6030_gpadc_driver = {
978 	.probe		= twl6030_gpadc_probe,
979 	.remove		= twl6030_gpadc_remove,
980 	.driver		= {
981 		.name	= DRIVER_NAME,
982 		.pm	= &twl6030_gpadc_pm_ops,
983 		.of_match_table = of_twl6030_match_tbl,
984 	},
985 };
986 
987 module_platform_driver(twl6030_gpadc_driver);
988 
989 MODULE_ALIAS("platform:" DRIVER_NAME);
990 MODULE_AUTHOR("Balaji T K <balajitk@ti.com>");
991 MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
992 MODULE_AUTHOR("Oleksandr Kozaruk <oleksandr.kozaruk@ti.com");
993 MODULE_DESCRIPTION("twl6030 ADC driver");
994 MODULE_LICENSE("GPL");
995