xref: /linux/drivers/iio/adc/twl6030-gpadc.c (revision 96ac6d435100450f0565708d9b885ea2a7400e0a)
1 /*
2  * TWL6030 GPADC module driver
3  *
4  * Copyright (C) 2009-2013 Texas Instruments Inc.
5  * Nishant Kamat <nskamat@ti.com>
6  * Balaji T K <balajitk@ti.com>
7  * Graeme Gregory <gg@slimlogic.co.uk>
8  * Girish S Ghongdemath <girishsg@ti.com>
9  * Ambresh K <ambresh@ti.com>
10  * Oleksandr Kozaruk <oleksandr.kozaruk@ti.com
11  *
12  * Based on twl4030-madc.c
13  * Copyright (C) 2008 Nokia Corporation
14  * Mikko Ylinen <mikko.k.ylinen@nokia.com>
15  *
16  * This program is free software; you can redistribute it and/or
17  * modify it under the terms of the GNU General Public License
18  * version 2 as published by the Free Software Foundation.
19  *
20  * This program is distributed in the hope that it will be useful, but
21  * WITHOUT ANY WARRANTY; without even the implied warranty of
22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
23  * General Public License for more details.
24  *
25  * You should have received a copy of the GNU General Public License
26  * along with this program; if not, write to the Free Software
27  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
28  * 02110-1301 USA
29  *
30  */
31 #include <linux/interrupt.h>
32 #include <linux/kernel.h>
33 #include <linux/module.h>
34 #include <linux/platform_device.h>
35 #include <linux/of_platform.h>
36 #include <linux/mfd/twl.h>
37 #include <linux/iio/iio.h>
38 #include <linux/iio/sysfs.h>
39 
40 #define DRIVER_NAME		"twl6030_gpadc"
41 
42 /*
43  * twl6030 per TRM has 17 channels, and twl6032 has 19 channels
44  * 2 test network channels are not used,
45  * 2 die temperature channels are not used either, as it is not
46  * defined how to convert ADC value to temperature
47  */
48 #define TWL6030_GPADC_USED_CHANNELS		13
49 #define TWL6030_GPADC_MAX_CHANNELS		15
50 #define TWL6032_GPADC_USED_CHANNELS		15
51 #define TWL6032_GPADC_MAX_CHANNELS		19
52 #define TWL6030_GPADC_NUM_TRIM_REGS		16
53 
54 #define TWL6030_GPADC_CTRL_P1			0x05
55 
56 #define TWL6032_GPADC_GPSELECT_ISB		0x07
57 #define TWL6032_GPADC_CTRL_P1			0x08
58 
59 #define TWL6032_GPADC_GPCH0_LSB			0x0d
60 #define TWL6032_GPADC_GPCH0_MSB			0x0e
61 
62 #define TWL6030_GPADC_CTRL_P1_SP1		BIT(3)
63 
64 #define TWL6030_GPADC_GPCH0_LSB			(0x29)
65 
66 #define TWL6030_GPADC_RT_SW1_EOC_MASK		BIT(5)
67 
68 #define TWL6030_GPADC_TRIM1			0xCD
69 
70 #define TWL6030_REG_TOGGLE1			0x90
71 #define TWL6030_GPADCS				BIT(1)
72 #define TWL6030_GPADCR				BIT(0)
73 
74 /**
75  * struct twl6030_chnl_calib - channel calibration
76  * @gain:		slope coefficient for ideal curve
77  * @gain_error:		gain error
78  * @offset_error:	offset of the real curve
79  */
80 struct twl6030_chnl_calib {
81 	s32 gain;
82 	s32 gain_error;
83 	s32 offset_error;
84 };
85 
86 /**
87  * struct twl6030_ideal_code - GPADC calibration parameters
88  * GPADC is calibrated in two points: close to the beginning and
89  * to the and of the measurable input range
90  *
91  * @channel:	channel number
92  * @code1:	ideal code for the input at the beginning
93  * @code2:	ideal code for at the end of the range
94  * @volt1:	voltage input at the beginning(low voltage)
95  * @volt2:	voltage input at the end(high voltage)
96  */
97 struct twl6030_ideal_code {
98 	int channel;
99 	u16 code1;
100 	u16 code2;
101 	u16 volt1;
102 	u16 volt2;
103 };
104 
105 struct twl6030_gpadc_data;
106 
107 /**
108  * struct twl6030_gpadc_platform_data - platform specific data
109  * @nchannels:		number of GPADC channels
110  * @iio_channels:	iio channels
111  * @twl6030_ideal:	pointer to calibration parameters
112  * @start_conversion:	pointer to ADC start conversion function
113  * @channel_to_reg	pointer to ADC function to convert channel to
114  *			register address for reading conversion result
115  * @calibrate:		pointer to calibration function
116  */
117 struct twl6030_gpadc_platform_data {
118 	const int nchannels;
119 	const struct iio_chan_spec *iio_channels;
120 	const struct twl6030_ideal_code *ideal;
121 	int (*start_conversion)(int channel);
122 	u8 (*channel_to_reg)(int channel);
123 	int (*calibrate)(struct twl6030_gpadc_data *gpadc);
124 };
125 
126 /**
127  * struct twl6030_gpadc_data - GPADC data
128  * @dev:		device pointer
129  * @lock:		mutual exclusion lock for the structure
130  * @irq_complete:	completion to signal end of conversion
131  * @twl6030_cal_tbl:	pointer to calibration data for each
132  *			channel with gain error and offset
133  * @pdata:		pointer to device specific data
134  */
135 struct twl6030_gpadc_data {
136 	struct device	*dev;
137 	struct mutex	lock;
138 	struct completion	irq_complete;
139 	struct twl6030_chnl_calib	*twl6030_cal_tbl;
140 	const struct twl6030_gpadc_platform_data *pdata;
141 };
142 
143 /*
144  * channels 11, 12, 13, 15 and 16 have no calibration data
145  * calibration offset is same for channels 1, 3, 4, 5
146  *
147  * The data is taken from GPADC_TRIM registers description.
148  * GPADC_TRIM registers keep difference between the code measured
149  * at volt1 and volt2 input voltages and corresponding code1 and code2
150  */
151 static const struct twl6030_ideal_code
152 	twl6030_ideal[TWL6030_GPADC_USED_CHANNELS] = {
153 	[0] = { /* ch 0, external, battery type, resistor value */
154 		.channel = 0,
155 		.code1 = 116,
156 		.code2 = 745,
157 		.volt1 = 141,
158 		.volt2 = 910,
159 	},
160 	[1] = { /* ch 1, external, battery temperature, NTC resistor value */
161 		.channel = 1,
162 		.code1 = 82,
163 		.code2 = 900,
164 		.volt1 = 100,
165 		.volt2 = 1100,
166 	},
167 	[2] = { /* ch 2, external, audio accessory/general purpose */
168 		.channel = 2,
169 		.code1 = 55,
170 		.code2 = 818,
171 		.volt1 = 101,
172 		.volt2 = 1499,
173 	},
174 	[3] = { /* ch 3, external, general purpose */
175 		.channel = 3,
176 		.code1 = 82,
177 		.code2 = 900,
178 		.volt1 = 100,
179 		.volt2 = 1100,
180 	},
181 	[4] = { /* ch 4, external, temperature measurement/general purpose */
182 		.channel = 4,
183 		.code1 = 82,
184 		.code2 = 900,
185 		.volt1 = 100,
186 		.volt2 = 1100,
187 	},
188 	[5] = { /* ch 5, external, general purpose */
189 		.channel = 5,
190 		.code1 = 82,
191 		.code2 = 900,
192 		.volt1 = 100,
193 		.volt2 = 1100,
194 	},
195 	[6] = { /* ch 6, external, general purpose */
196 		.channel = 6,
197 		.code1 = 82,
198 		.code2 = 900,
199 		.volt1 = 100,
200 		.volt2 = 1100,
201 	},
202 	[7] = { /* ch 7, internal, main battery */
203 		.channel = 7,
204 		.code1 = 614,
205 		.code2 = 941,
206 		.volt1 = 3001,
207 		.volt2 = 4599,
208 	},
209 	[8] = { /* ch 8, internal, backup battery */
210 		.channel = 8,
211 		.code1 = 82,
212 		.code2 = 688,
213 		.volt1 = 501,
214 		.volt2 = 4203,
215 	},
216 	[9] = { /* ch 9, internal, external charger input */
217 		.channel = 9,
218 		.code1 = 182,
219 		.code2 = 818,
220 		.volt1 = 2001,
221 		.volt2 = 8996,
222 	},
223 	[10] = { /* ch 10, internal, VBUS */
224 		.channel = 10,
225 		.code1 = 149,
226 		.code2 = 818,
227 		.volt1 = 1001,
228 		.volt2 = 5497,
229 	},
230 	[11] = { /* ch 11, internal, VBUS charging current */
231 		.channel = 11,
232 	},
233 		/* ch 12, internal, Die temperature */
234 		/* ch 13, internal, Die temperature */
235 	[12] = { /* ch 14, internal, USB ID line */
236 		.channel = 14,
237 		.code1 = 48,
238 		.code2 = 714,
239 		.volt1 = 323,
240 		.volt2 = 4800,
241 	},
242 };
243 
244 static const struct twl6030_ideal_code
245 			twl6032_ideal[TWL6032_GPADC_USED_CHANNELS] = {
246 	[0] = { /* ch 0, external, battery type, resistor value */
247 		.channel = 0,
248 		.code1 = 1441,
249 		.code2 = 3276,
250 		.volt1 = 440,
251 		.volt2 = 1000,
252 	},
253 	[1] = { /* ch 1, external, battery temperature, NTC resistor value */
254 		.channel = 1,
255 		.code1 = 1441,
256 		.code2 = 3276,
257 		.volt1 = 440,
258 		.volt2 = 1000,
259 	},
260 	[2] = { /* ch 2, external, audio accessory/general purpose */
261 		.channel = 2,
262 		.code1 = 1441,
263 		.code2 = 3276,
264 		.volt1 = 660,
265 		.volt2 = 1500,
266 	},
267 	[3] = { /* ch 3, external, temperature with external diode/general
268 								purpose */
269 		.channel = 3,
270 		.code1 = 1441,
271 		.code2 = 3276,
272 		.volt1 = 440,
273 		.volt2 = 1000,
274 	},
275 	[4] = { /* ch 4, external, temperature measurement/general purpose */
276 		.channel = 4,
277 		.code1 = 1441,
278 		.code2 = 3276,
279 		.volt1 = 440,
280 		.volt2 = 1000,
281 	},
282 	[5] = { /* ch 5, external, general purpose */
283 		.channel = 5,
284 		.code1 = 1441,
285 		.code2 = 3276,
286 		.volt1 = 440,
287 		.volt2 = 1000,
288 	},
289 	[6] = { /* ch 6, external, general purpose */
290 		.channel = 6,
291 		.code1 = 1441,
292 		.code2 = 3276,
293 		.volt1 = 440,
294 		.volt2 = 1000,
295 	},
296 	[7] = { /* ch7, internal, system supply */
297 		.channel = 7,
298 		.code1 = 1441,
299 		.code2 = 3276,
300 		.volt1 = 2200,
301 		.volt2 = 5000,
302 	},
303 	[8] = { /* ch8, internal, backup battery */
304 		.channel = 8,
305 		.code1 = 1441,
306 		.code2 = 3276,
307 		.volt1 = 2200,
308 		.volt2 = 5000,
309 	},
310 	[9] = { /* ch 9, internal, external charger input */
311 		.channel = 9,
312 		.code1 = 1441,
313 		.code2 = 3276,
314 		.volt1 = 3960,
315 		.volt2 = 9000,
316 	},
317 	[10] = { /* ch10, internal, VBUS */
318 		.channel = 10,
319 		.code1 = 150,
320 		.code2 = 751,
321 		.volt1 = 1000,
322 		.volt2 = 5000,
323 	},
324 	[11] = { /* ch 11, internal, VBUS DC-DC output current */
325 		.channel = 11,
326 		.code1 = 1441,
327 		.code2 = 3276,
328 		.volt1 = 660,
329 		.volt2 = 1500,
330 	},
331 		/* ch 12, internal, Die temperature */
332 		/* ch 13, internal, Die temperature */
333 	[12] = { /* ch 14, internal, USB ID line */
334 		.channel = 14,
335 		.code1 = 1441,
336 		.code2 = 3276,
337 		.volt1 = 2420,
338 		.volt2 = 5500,
339 	},
340 		/* ch 15, internal, test network */
341 		/* ch 16, internal, test network */
342 	[13] = { /* ch 17, internal, battery charging current */
343 		.channel = 17,
344 	},
345 	[14] = { /* ch 18, internal, battery voltage */
346 		.channel = 18,
347 		.code1 = 1441,
348 		.code2 = 3276,
349 		.volt1 = 2200,
350 		.volt2 = 5000,
351 	},
352 };
353 
354 static inline int twl6030_gpadc_write(u8 reg, u8 val)
355 {
356 	return twl_i2c_write_u8(TWL6030_MODULE_GPADC, val, reg);
357 }
358 
359 static inline int twl6030_gpadc_read(u8 reg, u8 *val)
360 {
361 
362 	return twl_i2c_read(TWL6030_MODULE_GPADC, val, reg, 2);
363 }
364 
365 static int twl6030_gpadc_enable_irq(u8 mask)
366 {
367 	int ret;
368 
369 	ret = twl6030_interrupt_unmask(mask, REG_INT_MSK_LINE_B);
370 	if (ret < 0)
371 		return ret;
372 
373 	ret = twl6030_interrupt_unmask(mask, REG_INT_MSK_STS_B);
374 
375 	return ret;
376 }
377 
378 static void twl6030_gpadc_disable_irq(u8 mask)
379 {
380 	twl6030_interrupt_mask(mask, REG_INT_MSK_LINE_B);
381 	twl6030_interrupt_mask(mask, REG_INT_MSK_STS_B);
382 }
383 
384 static irqreturn_t twl6030_gpadc_irq_handler(int irq, void *indio_dev)
385 {
386 	struct twl6030_gpadc_data *gpadc = iio_priv(indio_dev);
387 
388 	complete(&gpadc->irq_complete);
389 
390 	return IRQ_HANDLED;
391 }
392 
393 static int twl6030_start_conversion(int channel)
394 {
395 	return twl6030_gpadc_write(TWL6030_GPADC_CTRL_P1,
396 					TWL6030_GPADC_CTRL_P1_SP1);
397 }
398 
399 static int twl6032_start_conversion(int channel)
400 {
401 	int ret;
402 
403 	ret = twl6030_gpadc_write(TWL6032_GPADC_GPSELECT_ISB, channel);
404 	if (ret)
405 		return ret;
406 
407 	return twl6030_gpadc_write(TWL6032_GPADC_CTRL_P1,
408 						TWL6030_GPADC_CTRL_P1_SP1);
409 }
410 
411 static u8 twl6030_channel_to_reg(int channel)
412 {
413 	return TWL6030_GPADC_GPCH0_LSB + 2 * channel;
414 }
415 
416 static u8 twl6032_channel_to_reg(int channel)
417 {
418 	/*
419 	 * for any prior chosen channel, when the conversion is ready
420 	 * the result is avalable in GPCH0_LSB, GPCH0_MSB.
421 	 */
422 
423 	return TWL6032_GPADC_GPCH0_LSB;
424 }
425 
426 static int twl6030_gpadc_lookup(const struct twl6030_ideal_code *ideal,
427 		int channel, int size)
428 {
429 	int i;
430 
431 	for (i = 0; i < size; i++)
432 		if (ideal[i].channel == channel)
433 			break;
434 
435 	return i;
436 }
437 
438 static int twl6030_channel_calibrated(const struct twl6030_gpadc_platform_data
439 		*pdata, int channel)
440 {
441 	const struct twl6030_ideal_code *ideal = pdata->ideal;
442 	int i;
443 
444 	i = twl6030_gpadc_lookup(ideal, channel, pdata->nchannels);
445 	/* not calibrated channels have 0 in all structure members */
446 	return pdata->ideal[i].code2;
447 }
448 
449 static int twl6030_gpadc_make_correction(struct twl6030_gpadc_data *gpadc,
450 		int channel, int raw_code)
451 {
452 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
453 	int corrected_code;
454 	int i;
455 
456 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
457 	corrected_code = ((raw_code * 1000) -
458 		gpadc->twl6030_cal_tbl[i].offset_error) /
459 		gpadc->twl6030_cal_tbl[i].gain_error;
460 
461 	return corrected_code;
462 }
463 
464 static int twl6030_gpadc_get_raw(struct twl6030_gpadc_data *gpadc,
465 		int channel, int *res)
466 {
467 	u8 reg = gpadc->pdata->channel_to_reg(channel);
468 	__le16 val;
469 	int raw_code;
470 	int ret;
471 
472 	ret = twl6030_gpadc_read(reg, (u8 *)&val);
473 	if (ret) {
474 		dev_dbg(gpadc->dev, "unable to read register 0x%X\n", reg);
475 		return ret;
476 	}
477 
478 	raw_code = le16_to_cpu(val);
479 	dev_dbg(gpadc->dev, "GPADC raw code: %d", raw_code);
480 
481 	if (twl6030_channel_calibrated(gpadc->pdata, channel))
482 		*res = twl6030_gpadc_make_correction(gpadc, channel, raw_code);
483 	else
484 		*res = raw_code;
485 
486 	return ret;
487 }
488 
489 static int twl6030_gpadc_get_processed(struct twl6030_gpadc_data *gpadc,
490 		int channel, int *val)
491 {
492 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
493 	int corrected_code;
494 	int channel_value;
495 	int i;
496 	int ret;
497 
498 	ret = twl6030_gpadc_get_raw(gpadc, channel, &corrected_code);
499 	if (ret)
500 		return ret;
501 
502 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
503 	channel_value = corrected_code *
504 			gpadc->twl6030_cal_tbl[i].gain;
505 
506 	/* Shift back into mV range */
507 	channel_value /= 1000;
508 
509 	dev_dbg(gpadc->dev, "GPADC corrected code: %d", corrected_code);
510 	dev_dbg(gpadc->dev, "GPADC value: %d", channel_value);
511 
512 	*val = channel_value;
513 
514 	return ret;
515 }
516 
517 static int twl6030_gpadc_read_raw(struct iio_dev *indio_dev,
518 			     const struct iio_chan_spec *chan,
519 			     int *val, int *val2, long mask)
520 {
521 	struct twl6030_gpadc_data *gpadc = iio_priv(indio_dev);
522 	int ret;
523 	long timeout;
524 
525 	mutex_lock(&gpadc->lock);
526 
527 	ret = gpadc->pdata->start_conversion(chan->channel);
528 	if (ret) {
529 		dev_err(gpadc->dev, "failed to start conversion\n");
530 		goto err;
531 	}
532 	/* wait for conversion to complete */
533 	timeout = wait_for_completion_interruptible_timeout(
534 				&gpadc->irq_complete, msecs_to_jiffies(5000));
535 	if (timeout == 0) {
536 		ret = -ETIMEDOUT;
537 		goto err;
538 	} else if (timeout < 0) {
539 		ret = -EINTR;
540 		goto err;
541 	}
542 
543 	switch (mask) {
544 	case IIO_CHAN_INFO_RAW:
545 		ret = twl6030_gpadc_get_raw(gpadc, chan->channel, val);
546 		ret = ret ? -EIO : IIO_VAL_INT;
547 		break;
548 
549 	case IIO_CHAN_INFO_PROCESSED:
550 		ret = twl6030_gpadc_get_processed(gpadc, chan->channel, val);
551 		ret = ret ? -EIO : IIO_VAL_INT;
552 		break;
553 
554 	default:
555 		break;
556 	}
557 err:
558 	mutex_unlock(&gpadc->lock);
559 
560 	return ret;
561 }
562 
563 /*
564  * The GPADC channels are calibrated using a two point calibration method.
565  * The channels measured with two known values: volt1 and volt2, and
566  * ideal corresponding output codes are known: code1, code2.
567  * The difference(d1, d2) between ideal and measured codes stored in trim
568  * registers.
569  * The goal is to find offset and gain of the real curve for each calibrated
570  * channel.
571  * gain: k = 1 + ((d2 - d1) / (x2 - x1))
572  * offset: b = d1 + (k - 1) * x1
573  */
574 static void twl6030_calibrate_channel(struct twl6030_gpadc_data *gpadc,
575 		int channel, int d1, int d2)
576 {
577 	int b, k, gain, x1, x2, i;
578 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
579 
580 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
581 
582 	/* Gain */
583 	gain = ((ideal[i].volt2 - ideal[i].volt1) * 1000) /
584 		(ideal[i].code2 - ideal[i].code1);
585 
586 	x1 = ideal[i].code1;
587 	x2 = ideal[i].code2;
588 
589 	/* k - real curve gain */
590 	k = 1000 + (((d2 - d1) * 1000) / (x2 - x1));
591 
592 	/* b - offset of the real curve gain */
593 	b = (d1 * 1000) - (k - 1000) * x1;
594 
595 	gpadc->twl6030_cal_tbl[i].gain = gain;
596 	gpadc->twl6030_cal_tbl[i].gain_error = k;
597 	gpadc->twl6030_cal_tbl[i].offset_error = b;
598 
599 	dev_dbg(gpadc->dev, "GPADC d1   for Chn: %d = %d\n", channel, d1);
600 	dev_dbg(gpadc->dev, "GPADC d2   for Chn: %d = %d\n", channel, d2);
601 	dev_dbg(gpadc->dev, "GPADC x1   for Chn: %d = %d\n", channel, x1);
602 	dev_dbg(gpadc->dev, "GPADC x2   for Chn: %d = %d\n", channel, x2);
603 	dev_dbg(gpadc->dev, "GPADC Gain for Chn: %d = %d\n", channel, gain);
604 	dev_dbg(gpadc->dev, "GPADC k    for Chn: %d = %d\n", channel, k);
605 	dev_dbg(gpadc->dev, "GPADC b    for Chn: %d = %d\n", channel, b);
606 }
607 
608 static inline int twl6030_gpadc_get_trim_offset(s8 d)
609 {
610 	/*
611 	 * XXX NOTE!
612 	 * bit 0 - sign, bit 7 - reserved, 6..1 - trim value
613 	 * though, the documentation states that trim value
614 	 * is absolute value, the correct conversion results are
615 	 * obtained if the value is interpreted as 2's complement.
616 	 */
617 	__u32 temp = ((d & 0x7f) >> 1) | ((d & 1) << 6);
618 
619 	return sign_extend32(temp, 6);
620 }
621 
622 static int twl6030_calibration(struct twl6030_gpadc_data *gpadc)
623 {
624 	int ret;
625 	int chn;
626 	u8 trim_regs[TWL6030_GPADC_NUM_TRIM_REGS];
627 	s8 d1, d2;
628 
629 	/*
630 	 * for calibration two measurements have been performed at
631 	 * factory, for some channels, during the production test and
632 	 * have been stored in registers. This two stored values are
633 	 * used to correct the measurements. The values represent
634 	 * offsets for the given input from the output on ideal curve.
635 	 */
636 	ret = twl_i2c_read(TWL6030_MODULE_ID2, trim_regs,
637 			TWL6030_GPADC_TRIM1, TWL6030_GPADC_NUM_TRIM_REGS);
638 	if (ret < 0) {
639 		dev_err(gpadc->dev, "calibration failed\n");
640 		return ret;
641 	}
642 
643 	for (chn = 0; chn < TWL6030_GPADC_MAX_CHANNELS; chn++) {
644 
645 		switch (chn) {
646 		case 0:
647 			d1 = trim_regs[0];
648 			d2 = trim_regs[1];
649 			break;
650 		case 1:
651 		case 3:
652 		case 4:
653 		case 5:
654 		case 6:
655 			d1 = trim_regs[4];
656 			d2 = trim_regs[5];
657 			break;
658 		case 2:
659 			d1 = trim_regs[12];
660 			d2 = trim_regs[13];
661 			break;
662 		case 7:
663 			d1 = trim_regs[6];
664 			d2 = trim_regs[7];
665 			break;
666 		case 8:
667 			d1 = trim_regs[2];
668 			d2 = trim_regs[3];
669 			break;
670 		case 9:
671 			d1 = trim_regs[8];
672 			d2 = trim_regs[9];
673 			break;
674 		case 10:
675 			d1 = trim_regs[10];
676 			d2 = trim_regs[11];
677 			break;
678 		case 14:
679 			d1 = trim_regs[14];
680 			d2 = trim_regs[15];
681 			break;
682 		default:
683 			continue;
684 		}
685 
686 		d1 = twl6030_gpadc_get_trim_offset(d1);
687 		d2 = twl6030_gpadc_get_trim_offset(d2);
688 
689 		twl6030_calibrate_channel(gpadc, chn, d1, d2);
690 	}
691 
692 	return 0;
693 }
694 
695 static int twl6032_get_trim_value(u8 *trim_regs, unsigned int reg0,
696 		unsigned int reg1, unsigned int mask0, unsigned int mask1,
697 		unsigned int shift0)
698 {
699 	int val;
700 
701 	val = (trim_regs[reg0] & mask0) << shift0;
702 	val |= (trim_regs[reg1] & mask1) >> 1;
703 	if (trim_regs[reg1] & 0x01)
704 		val = -val;
705 
706 	return val;
707 }
708 
709 static int twl6032_calibration(struct twl6030_gpadc_data *gpadc)
710 {
711 	int chn, d1 = 0, d2 = 0, temp;
712 	u8 trim_regs[TWL6030_GPADC_NUM_TRIM_REGS];
713 	int ret;
714 
715 	ret = twl_i2c_read(TWL6030_MODULE_ID2, trim_regs,
716 			TWL6030_GPADC_TRIM1, TWL6030_GPADC_NUM_TRIM_REGS);
717 	if (ret < 0) {
718 		dev_err(gpadc->dev, "calibration failed\n");
719 		return ret;
720 	}
721 
722 	/*
723 	 * Loop to calculate the value needed for returning voltages from
724 	 * GPADC not values.
725 	 *
726 	 * gain is calculated to 3 decimal places fixed point.
727 	 */
728 	for (chn = 0; chn < TWL6032_GPADC_MAX_CHANNELS; chn++) {
729 
730 		switch (chn) {
731 		case 0:
732 		case 1:
733 		case 2:
734 		case 3:
735 		case 4:
736 		case 5:
737 		case 6:
738 		case 11:
739 		case 14:
740 			d1 = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
741 								0x06, 2);
742 			d2 = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
743 								0x06, 2);
744 			break;
745 		case 8:
746 			temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
747 								0x06, 2);
748 			d1 = temp + twl6032_get_trim_value(trim_regs, 7, 6,
749 								0x18, 0x1E, 1);
750 
751 			temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3F,
752 								0x06, 2);
753 			d2 = temp + twl6032_get_trim_value(trim_regs, 9, 7,
754 								0x1F, 0x06, 2);
755 			break;
756 		case 9:
757 			temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
758 								0x06, 2);
759 			d1 = temp + twl6032_get_trim_value(trim_regs, 13, 11,
760 								0x18, 0x1E, 1);
761 
762 			temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
763 								0x06, 2);
764 			d2 = temp + twl6032_get_trim_value(trim_regs, 15, 13,
765 								0x1F, 0x06, 1);
766 			break;
767 		case 10:
768 			d1 = twl6032_get_trim_value(trim_regs, 10, 8, 0x0f,
769 								0x0E, 3);
770 			d2 = twl6032_get_trim_value(trim_regs, 14, 12, 0x0f,
771 								0x0E, 3);
772 			break;
773 		case 7:
774 		case 18:
775 			temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
776 								0x06, 2);
777 
778 			d1 = (trim_regs[4] & 0x7E) >> 1;
779 			if (trim_regs[4] & 0x01)
780 				d1 = -d1;
781 			d1 += temp;
782 
783 			temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
784 								0x06, 2);
785 
786 			d2 = (trim_regs[5] & 0xFE) >> 1;
787 			if (trim_regs[5] & 0x01)
788 				d2 = -d2;
789 
790 			d2 += temp;
791 			break;
792 		default:
793 			/* No data for other channels */
794 			continue;
795 		}
796 
797 		twl6030_calibrate_channel(gpadc, chn, d1, d2);
798 	}
799 
800 	return 0;
801 }
802 
803 #define TWL6030_GPADC_CHAN(chn, _type, chan_info) {	\
804 	.type = _type,					\
805 	.channel = chn,					\
806 	.info_mask_separate = BIT(chan_info),		\
807 	.indexed = 1,					\
808 }
809 
810 static const struct iio_chan_spec twl6030_gpadc_iio_channels[] = {
811 	TWL6030_GPADC_CHAN(0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
812 	TWL6030_GPADC_CHAN(1, IIO_TEMP, IIO_CHAN_INFO_RAW),
813 	TWL6030_GPADC_CHAN(2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
814 	TWL6030_GPADC_CHAN(3, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
815 	TWL6030_GPADC_CHAN(4, IIO_TEMP, IIO_CHAN_INFO_RAW),
816 	TWL6030_GPADC_CHAN(5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
817 	TWL6030_GPADC_CHAN(6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
818 	TWL6030_GPADC_CHAN(7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
819 	TWL6030_GPADC_CHAN(8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
820 	TWL6030_GPADC_CHAN(9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
821 	TWL6030_GPADC_CHAN(10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
822 	TWL6030_GPADC_CHAN(11, IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
823 	TWL6030_GPADC_CHAN(14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
824 };
825 
826 static const struct iio_chan_spec twl6032_gpadc_iio_channels[] = {
827 	TWL6030_GPADC_CHAN(0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
828 	TWL6030_GPADC_CHAN(1, IIO_TEMP, IIO_CHAN_INFO_RAW),
829 	TWL6030_GPADC_CHAN(2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
830 	TWL6030_GPADC_CHAN(3, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
831 	TWL6030_GPADC_CHAN(4, IIO_TEMP, IIO_CHAN_INFO_RAW),
832 	TWL6030_GPADC_CHAN(5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
833 	TWL6030_GPADC_CHAN(6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
834 	TWL6030_GPADC_CHAN(7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
835 	TWL6030_GPADC_CHAN(8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
836 	TWL6030_GPADC_CHAN(9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
837 	TWL6030_GPADC_CHAN(10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
838 	TWL6030_GPADC_CHAN(11, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
839 	TWL6030_GPADC_CHAN(14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
840 	TWL6030_GPADC_CHAN(17, IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
841 	TWL6030_GPADC_CHAN(18, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
842 };
843 
844 static const struct iio_info twl6030_gpadc_iio_info = {
845 	.read_raw = &twl6030_gpadc_read_raw,
846 };
847 
848 static const struct twl6030_gpadc_platform_data twl6030_pdata = {
849 	.iio_channels = twl6030_gpadc_iio_channels,
850 	.nchannels = TWL6030_GPADC_USED_CHANNELS,
851 	.ideal = twl6030_ideal,
852 	.start_conversion = twl6030_start_conversion,
853 	.channel_to_reg = twl6030_channel_to_reg,
854 	.calibrate = twl6030_calibration,
855 };
856 
857 static const struct twl6030_gpadc_platform_data twl6032_pdata = {
858 	.iio_channels = twl6032_gpadc_iio_channels,
859 	.nchannels = TWL6032_GPADC_USED_CHANNELS,
860 	.ideal = twl6032_ideal,
861 	.start_conversion = twl6032_start_conversion,
862 	.channel_to_reg = twl6032_channel_to_reg,
863 	.calibrate = twl6032_calibration,
864 };
865 
866 static const struct of_device_id of_twl6030_match_tbl[] = {
867 	{
868 		.compatible = "ti,twl6030-gpadc",
869 		.data = &twl6030_pdata,
870 	},
871 	{
872 		.compatible = "ti,twl6032-gpadc",
873 		.data = &twl6032_pdata,
874 	},
875 	{ /* end */ }
876 };
877 MODULE_DEVICE_TABLE(of, of_twl6030_match_tbl);
878 
879 static int twl6030_gpadc_probe(struct platform_device *pdev)
880 {
881 	struct device *dev = &pdev->dev;
882 	struct twl6030_gpadc_data *gpadc;
883 	const struct twl6030_gpadc_platform_data *pdata;
884 	const struct of_device_id *match;
885 	struct iio_dev *indio_dev;
886 	int irq;
887 	int ret;
888 
889 	match = of_match_device(of_twl6030_match_tbl, dev);
890 	if (!match)
891 		return -EINVAL;
892 
893 	pdata = match->data;
894 
895 	indio_dev = devm_iio_device_alloc(dev, sizeof(*gpadc));
896 	if (!indio_dev)
897 		return -ENOMEM;
898 
899 	gpadc = iio_priv(indio_dev);
900 
901 	gpadc->twl6030_cal_tbl = devm_kcalloc(dev,
902 					pdata->nchannels,
903 					sizeof(*gpadc->twl6030_cal_tbl),
904 					GFP_KERNEL);
905 	if (!gpadc->twl6030_cal_tbl)
906 		return -ENOMEM;
907 
908 	gpadc->dev = dev;
909 	gpadc->pdata = pdata;
910 
911 	platform_set_drvdata(pdev, indio_dev);
912 	mutex_init(&gpadc->lock);
913 	init_completion(&gpadc->irq_complete);
914 
915 	ret = pdata->calibrate(gpadc);
916 	if (ret < 0) {
917 		dev_err(&pdev->dev, "failed to read calibration registers\n");
918 		return ret;
919 	}
920 
921 	irq = platform_get_irq(pdev, 0);
922 	if (irq < 0) {
923 		dev_err(&pdev->dev, "failed to get irq\n");
924 		return irq;
925 	}
926 
927 	ret = devm_request_threaded_irq(dev, irq, NULL,
928 				twl6030_gpadc_irq_handler,
929 				IRQF_ONESHOT, "twl6030_gpadc", indio_dev);
930 
931 	ret = twl6030_gpadc_enable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK);
932 	if (ret < 0) {
933 		dev_err(&pdev->dev, "failed to enable GPADC interrupt\n");
934 		return ret;
935 	}
936 
937 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS,
938 					TWL6030_REG_TOGGLE1);
939 	if (ret < 0) {
940 		dev_err(&pdev->dev, "failed to enable GPADC module\n");
941 		return ret;
942 	}
943 
944 	indio_dev->name = DRIVER_NAME;
945 	indio_dev->dev.parent = dev;
946 	indio_dev->info = &twl6030_gpadc_iio_info;
947 	indio_dev->modes = INDIO_DIRECT_MODE;
948 	indio_dev->channels = pdata->iio_channels;
949 	indio_dev->num_channels = pdata->nchannels;
950 
951 	return iio_device_register(indio_dev);
952 }
953 
954 static int twl6030_gpadc_remove(struct platform_device *pdev)
955 {
956 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
957 
958 	twl6030_gpadc_disable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK);
959 	iio_device_unregister(indio_dev);
960 
961 	return 0;
962 }
963 
964 #ifdef CONFIG_PM_SLEEP
965 static int twl6030_gpadc_suspend(struct device *pdev)
966 {
967 	int ret;
968 
969 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCR,
970 				TWL6030_REG_TOGGLE1);
971 	if (ret)
972 		dev_err(pdev, "error resetting GPADC (%d)!\n", ret);
973 
974 	return 0;
975 };
976 
977 static int twl6030_gpadc_resume(struct device *pdev)
978 {
979 	int ret;
980 
981 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS,
982 				TWL6030_REG_TOGGLE1);
983 	if (ret)
984 		dev_err(pdev, "error setting GPADC (%d)!\n", ret);
985 
986 	return 0;
987 };
988 #endif
989 
990 static SIMPLE_DEV_PM_OPS(twl6030_gpadc_pm_ops, twl6030_gpadc_suspend,
991 					twl6030_gpadc_resume);
992 
993 static struct platform_driver twl6030_gpadc_driver = {
994 	.probe		= twl6030_gpadc_probe,
995 	.remove		= twl6030_gpadc_remove,
996 	.driver		= {
997 		.name	= DRIVER_NAME,
998 		.pm	= &twl6030_gpadc_pm_ops,
999 		.of_match_table = of_twl6030_match_tbl,
1000 	},
1001 };
1002 
1003 module_platform_driver(twl6030_gpadc_driver);
1004 
1005 MODULE_ALIAS("platform:" DRIVER_NAME);
1006 MODULE_AUTHOR("Balaji T K <balajitk@ti.com>");
1007 MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
1008 MODULE_AUTHOR("Oleksandr Kozaruk <oleksandr.kozaruk@ti.com");
1009 MODULE_DESCRIPTION("twl6030 ADC driver");
1010 MODULE_LICENSE("GPL");
1011