xref: /linux/drivers/iio/adc/twl6030-gpadc.c (revision 40d269c000bda9fcd276a0412a9cebd3f6e344c5)
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/mod_devicetable.h>
20 #include <linux/module.h>
21 #include <linux/platform_device.h>
22 #include <linux/property.h>
23 #include <linux/mfd/twl.h>
24 #include <linux/iio/iio.h>
25 #include <linux/iio/sysfs.h>
26 
27 #define DRIVER_NAME		"twl6030_gpadc"
28 
29 /*
30  * twl6030 per TRM has 17 channels, and twl6032 has 19 channels
31  * 2 test network channels are not used,
32  * 2 die temperature channels are not used either, as it is not
33  * defined how to convert ADC value to temperature
34  */
35 #define TWL6030_GPADC_USED_CHANNELS		13
36 #define TWL6030_GPADC_MAX_CHANNELS		15
37 #define TWL6032_GPADC_USED_CHANNELS		15
38 #define TWL6032_GPADC_MAX_CHANNELS		19
39 #define TWL6030_GPADC_NUM_TRIM_REGS		16
40 
41 #define TWL6030_GPADC_CTRL_P1			0x05
42 
43 #define TWL6032_GPADC_GPSELECT_ISB		0x07
44 #define TWL6032_GPADC_CTRL_P1			0x08
45 
46 #define TWL6032_GPADC_GPCH0_LSB			0x0d
47 #define TWL6032_GPADC_GPCH0_MSB			0x0e
48 
49 #define TWL6030_GPADC_CTRL_P1_SP1		BIT(3)
50 
51 #define TWL6030_GPADC_GPCH0_LSB			(0x29)
52 
53 #define TWL6030_GPADC_RT_SW1_EOC_MASK		BIT(5)
54 
55 #define TWL6030_GPADC_TRIM1			0xCD
56 
57 #define TWL6030_REG_TOGGLE1			0x90
58 #define TWL6030_GPADCS				BIT(1)
59 #define TWL6030_GPADCR				BIT(0)
60 
61 #define USB_VBUS_CTRL_SET			0x04
62 #define USB_ID_CTRL_SET				0x06
63 
64 #define TWL6030_MISC1				0xE4
65 #define VBUS_MEAS				0x01
66 #define ID_MEAS					0x01
67 
68 #define VAC_MEAS                0x04
69 #define VBAT_MEAS               0x02
70 #define BB_MEAS                 0x01
71 
72 
73 /**
74  * struct twl6030_chnl_calib - channel calibration
75  * @gain:		slope coefficient for ideal curve
76  * @gain_error:		gain error
77  * @offset_error:	offset of the real curve
78  */
79 struct twl6030_chnl_calib {
80 	s32 gain;
81 	s32 gain_error;
82 	s32 offset_error;
83 };
84 
85 /**
86  * struct twl6030_ideal_code - GPADC calibration parameters
87  * GPADC is calibrated in two points: close to the beginning and
88  * to the and of the measurable input range
89  *
90  * @channel:	channel number
91  * @code1:	ideal code for the input at the beginning
92  * @code2:	ideal code for at the end of the range
93  * @volt1:	voltage input at the beginning(low voltage)
94  * @volt2:	voltage input at the end(high voltage)
95  */
96 struct twl6030_ideal_code {
97 	int channel;
98 	u16 code1;
99 	u16 code2;
100 	u16 volt1;
101 	u16 volt2;
102 };
103 
104 struct twl6030_gpadc_data;
105 
106 /**
107  * struct twl6030_gpadc_platform_data - platform specific data
108  * @nchannels:		number of GPADC channels
109  * @iio_channels:	iio channels
110  * @ideal:		pointer to calibration parameters
111  * @start_conversion:	pointer to ADC start conversion function
112  * @channel_to_reg:	pointer to ADC function to convert channel to
113  *			register address for reading conversion result
114  * @calibrate:		pointer to calibration function
115  */
116 struct twl6030_gpadc_platform_data {
117 	const int nchannels;
118 	const struct iio_chan_spec *iio_channels;
119 	const struct twl6030_ideal_code *ideal;
120 	int (*start_conversion)(int channel);
121 	u8 (*channel_to_reg)(int channel);
122 	int (*calibrate)(struct twl6030_gpadc_data *gpadc);
123 };
124 
125 /**
126  * struct twl6030_gpadc_data - GPADC data
127  * @dev:		device pointer
128  * @lock:		mutual exclusion lock for the structure
129  * @irq_complete:	completion to signal end of conversion
130  * @twl6030_cal_tbl:	pointer to calibration data for each
131  *			channel with gain error and offset
132  * @pdata:		pointer to device specific data
133  */
134 struct twl6030_gpadc_data {
135 	struct device	*dev;
136 	struct mutex	lock;
137 	struct completion	irq_complete;
138 	struct twl6030_chnl_calib	*twl6030_cal_tbl;
139 	const struct twl6030_gpadc_platform_data *pdata;
140 };
141 
142 /*
143  * channels 11, 12, 13, 15 and 16 have no calibration data
144  * calibration offset is same for channels 1, 3, 4, 5
145  *
146  * The data is taken from GPADC_TRIM registers description.
147  * GPADC_TRIM registers keep difference between the code measured
148  * at volt1 and volt2 input voltages and corresponding code1 and code2
149  */
150 static const struct twl6030_ideal_code
151 	twl6030_ideal[TWL6030_GPADC_USED_CHANNELS] = {
152 	[0] = { /* ch 0, external, battery type, resistor value */
153 		.channel = 0,
154 		.code1 = 116,
155 		.code2 = 745,
156 		.volt1 = 141,
157 		.volt2 = 910,
158 	},
159 	[1] = { /* ch 1, external, battery temperature, NTC resistor value */
160 		.channel = 1,
161 		.code1 = 82,
162 		.code2 = 900,
163 		.volt1 = 100,
164 		.volt2 = 1100,
165 	},
166 	[2] = { /* ch 2, external, audio accessory/general purpose */
167 		.channel = 2,
168 		.code1 = 55,
169 		.code2 = 818,
170 		.volt1 = 101,
171 		.volt2 = 1499,
172 	},
173 	[3] = { /* ch 3, external, general purpose */
174 		.channel = 3,
175 		.code1 = 82,
176 		.code2 = 900,
177 		.volt1 = 100,
178 		.volt2 = 1100,
179 	},
180 	[4] = { /* ch 4, external, temperature measurement/general purpose */
181 		.channel = 4,
182 		.code1 = 82,
183 		.code2 = 900,
184 		.volt1 = 100,
185 		.volt2 = 1100,
186 	},
187 	[5] = { /* ch 5, external, general purpose */
188 		.channel = 5,
189 		.code1 = 82,
190 		.code2 = 900,
191 		.volt1 = 100,
192 		.volt2 = 1100,
193 	},
194 	[6] = { /* ch 6, external, general purpose */
195 		.channel = 6,
196 		.code1 = 82,
197 		.code2 = 900,
198 		.volt1 = 100,
199 		.volt2 = 1100,
200 	},
201 	[7] = { /* ch 7, internal, main battery */
202 		.channel = 7,
203 		.code1 = 614,
204 		.code2 = 941,
205 		.volt1 = 3001,
206 		.volt2 = 4599,
207 	},
208 	[8] = { /* ch 8, internal, backup battery */
209 		.channel = 8,
210 		.code1 = 82,
211 		.code2 = 688,
212 		.volt1 = 501,
213 		.volt2 = 4203,
214 	},
215 	[9] = { /* ch 9, internal, external charger input */
216 		.channel = 9,
217 		.code1 = 182,
218 		.code2 = 818,
219 		.volt1 = 2001,
220 		.volt2 = 8996,
221 	},
222 	[10] = { /* ch 10, internal, VBUS */
223 		.channel = 10,
224 		.code1 = 149,
225 		.code2 = 818,
226 		.volt1 = 1001,
227 		.volt2 = 5497,
228 	},
229 	[11] = { /* ch 11, internal, VBUS charging current */
230 		.channel = 11,
231 	},
232 		/* ch 12, internal, Die temperature */
233 		/* ch 13, internal, Die temperature */
234 	[12] = { /* ch 14, internal, USB ID line */
235 		.channel = 14,
236 		.code1 = 48,
237 		.code2 = 714,
238 		.volt1 = 323,
239 		.volt2 = 4800,
240 	},
241 };
242 
243 static const struct twl6030_ideal_code
244 			twl6032_ideal[TWL6032_GPADC_USED_CHANNELS] = {
245 	[0] = { /* ch 0, external, battery type, resistor value */
246 		.channel = 0,
247 		.code1 = 1441,
248 		.code2 = 3276,
249 		.volt1 = 440,
250 		.volt2 = 1000,
251 	},
252 	[1] = { /* ch 1, external, battery temperature, NTC resistor value */
253 		.channel = 1,
254 		.code1 = 1441,
255 		.code2 = 3276,
256 		.volt1 = 440,
257 		.volt2 = 1000,
258 	},
259 	[2] = { /* ch 2, external, audio accessory/general purpose */
260 		.channel = 2,
261 		.code1 = 1441,
262 		.code2 = 3276,
263 		.volt1 = 660,
264 		.volt2 = 1500,
265 	},
266 	[3] = { /* ch 3, external, temperature with external diode/general
267 								purpose */
268 		.channel = 3,
269 		.code1 = 1441,
270 		.code2 = 3276,
271 		.volt1 = 440,
272 		.volt2 = 1000,
273 	},
274 	[4] = { /* ch 4, external, temperature measurement/general purpose */
275 		.channel = 4,
276 		.code1 = 1441,
277 		.code2 = 3276,
278 		.volt1 = 440,
279 		.volt2 = 1000,
280 	},
281 	[5] = { /* ch 5, external, general purpose */
282 		.channel = 5,
283 		.code1 = 1441,
284 		.code2 = 3276,
285 		.volt1 = 440,
286 		.volt2 = 1000,
287 	},
288 	[6] = { /* ch 6, external, general purpose */
289 		.channel = 6,
290 		.code1 = 1441,
291 		.code2 = 3276,
292 		.volt1 = 440,
293 		.volt2 = 1000,
294 	},
295 	[7] = { /* ch7, internal, system supply */
296 		.channel = 7,
297 		.code1 = 1441,
298 		.code2 = 3276,
299 		.volt1 = 2200,
300 		.volt2 = 5000,
301 	},
302 	[8] = { /* ch8, internal, backup battery */
303 		.channel = 8,
304 		.code1 = 1441,
305 		.code2 = 3276,
306 		.volt1 = 2200,
307 		.volt2 = 5000,
308 	},
309 	[9] = { /* ch 9, internal, external charger input */
310 		.channel = 9,
311 		.code1 = 1441,
312 		.code2 = 3276,
313 		.volt1 = 3960,
314 		.volt2 = 9000,
315 	},
316 	[10] = { /* ch10, internal, VBUS */
317 		.channel = 10,
318 		.code1 = 150,
319 		.code2 = 751,
320 		.volt1 = 1000,
321 		.volt2 = 5000,
322 	},
323 	[11] = { /* ch 11, internal, VBUS DC-DC output current */
324 		.channel = 11,
325 		.code1 = 1441,
326 		.code2 = 3276,
327 		.volt1 = 660,
328 		.volt2 = 1500,
329 	},
330 		/* ch 12, internal, Die temperature */
331 		/* ch 13, internal, Die temperature */
332 	[12] = { /* ch 14, internal, USB ID line */
333 		.channel = 14,
334 		.code1 = 1441,
335 		.code2 = 3276,
336 		.volt1 = 2420,
337 		.volt2 = 5500,
338 	},
339 		/* ch 15, internal, test network */
340 		/* ch 16, internal, test network */
341 	[13] = { /* ch 17, internal, battery charging current */
342 		.channel = 17,
343 	},
344 	[14] = { /* ch 18, internal, battery voltage */
345 		.channel = 18,
346 		.code1 = 1441,
347 		.code2 = 3276,
348 		.volt1 = 2200,
349 		.volt2 = 5000,
350 	},
351 };
352 
353 static inline int twl6030_gpadc_write(u8 reg, u8 val)
354 {
355 	return twl_i2c_write_u8(TWL6030_MODULE_GPADC, val, reg);
356 }
357 
358 static inline int twl6030_gpadc_read(u8 reg, u8 *val)
359 {
360 
361 	return twl_i2c_read(TWL6030_MODULE_GPADC, val, reg, 2);
362 }
363 
364 static int twl6030_gpadc_enable_irq(u8 mask)
365 {
366 	int ret;
367 
368 	ret = twl6030_interrupt_unmask(mask, REG_INT_MSK_LINE_B);
369 	if (ret < 0)
370 		return ret;
371 
372 	ret = twl6030_interrupt_unmask(mask, REG_INT_MSK_STS_B);
373 
374 	return ret;
375 }
376 
377 static void twl6030_gpadc_disable_irq(u8 mask)
378 {
379 	twl6030_interrupt_mask(mask, REG_INT_MSK_LINE_B);
380 	twl6030_interrupt_mask(mask, REG_INT_MSK_STS_B);
381 }
382 
383 static irqreturn_t twl6030_gpadc_irq_handler(int irq, void *indio_dev)
384 {
385 	struct twl6030_gpadc_data *gpadc = iio_priv(indio_dev);
386 
387 	complete(&gpadc->irq_complete);
388 
389 	return IRQ_HANDLED;
390 }
391 
392 static int twl6030_start_conversion(int channel)
393 {
394 	return twl6030_gpadc_write(TWL6030_GPADC_CTRL_P1,
395 					TWL6030_GPADC_CTRL_P1_SP1);
396 }
397 
398 static int twl6032_start_conversion(int channel)
399 {
400 	int ret;
401 
402 	ret = twl6030_gpadc_write(TWL6032_GPADC_GPSELECT_ISB, channel);
403 	if (ret)
404 		return ret;
405 
406 	return twl6030_gpadc_write(TWL6032_GPADC_CTRL_P1,
407 						TWL6030_GPADC_CTRL_P1_SP1);
408 }
409 
410 static u8 twl6030_channel_to_reg(int channel)
411 {
412 	return TWL6030_GPADC_GPCH0_LSB + 2 * channel;
413 }
414 
415 static u8 twl6032_channel_to_reg(int channel)
416 {
417 	/*
418 	 * for any prior chosen channel, when the conversion is ready
419 	 * the result is avalable in GPCH0_LSB, GPCH0_MSB.
420 	 */
421 
422 	return TWL6032_GPADC_GPCH0_LSB;
423 }
424 
425 static int twl6030_gpadc_lookup(const struct twl6030_ideal_code *ideal,
426 		int channel, int size)
427 {
428 	int i;
429 
430 	for (i = 0; i < size; i++)
431 		if (ideal[i].channel == channel)
432 			break;
433 
434 	return i;
435 }
436 
437 static int twl6030_channel_calibrated(const struct twl6030_gpadc_platform_data
438 		*pdata, int channel)
439 {
440 	const struct twl6030_ideal_code *ideal = pdata->ideal;
441 	int i;
442 
443 	i = twl6030_gpadc_lookup(ideal, channel, pdata->nchannels);
444 	/* not calibrated channels have 0 in all structure members */
445 	return pdata->ideal[i].code2;
446 }
447 
448 static int twl6030_gpadc_make_correction(struct twl6030_gpadc_data *gpadc,
449 		int channel, int raw_code)
450 {
451 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
452 	int corrected_code;
453 	int i;
454 
455 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
456 	corrected_code = ((raw_code * 1000) -
457 		gpadc->twl6030_cal_tbl[i].offset_error) /
458 		gpadc->twl6030_cal_tbl[i].gain_error;
459 
460 	return corrected_code;
461 }
462 
463 static int twl6030_gpadc_get_raw(struct twl6030_gpadc_data *gpadc,
464 		int channel, int *res)
465 {
466 	u8 reg = gpadc->pdata->channel_to_reg(channel);
467 	__le16 val;
468 	int raw_code;
469 	int ret;
470 
471 	ret = twl6030_gpadc_read(reg, (u8 *)&val);
472 	if (ret) {
473 		dev_dbg(gpadc->dev, "unable to read register 0x%X\n", reg);
474 		return ret;
475 	}
476 
477 	raw_code = le16_to_cpu(val);
478 	dev_dbg(gpadc->dev, "GPADC raw code: %d", raw_code);
479 
480 	if (twl6030_channel_calibrated(gpadc->pdata, channel))
481 		*res = twl6030_gpadc_make_correction(gpadc, channel, raw_code);
482 	else
483 		*res = raw_code;
484 
485 	return ret;
486 }
487 
488 static int twl6030_gpadc_get_processed(struct twl6030_gpadc_data *gpadc,
489 		int channel, int *val)
490 {
491 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
492 	int corrected_code;
493 	int channel_value;
494 	int i;
495 	int ret;
496 
497 	ret = twl6030_gpadc_get_raw(gpadc, channel, &corrected_code);
498 	if (ret)
499 		return ret;
500 
501 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
502 	channel_value = corrected_code *
503 			gpadc->twl6030_cal_tbl[i].gain;
504 
505 	/* Shift back into mV range */
506 	channel_value /= 1000;
507 
508 	dev_dbg(gpadc->dev, "GPADC corrected code: %d", corrected_code);
509 	dev_dbg(gpadc->dev, "GPADC value: %d", channel_value);
510 
511 	*val = channel_value;
512 
513 	return ret;
514 }
515 
516 static int twl6030_gpadc_read_raw(struct iio_dev *indio_dev,
517 			     const struct iio_chan_spec *chan,
518 			     int *val, int *val2, long mask)
519 {
520 	struct twl6030_gpadc_data *gpadc = iio_priv(indio_dev);
521 	int ret;
522 	long timeout;
523 
524 	mutex_lock(&gpadc->lock);
525 
526 	ret = gpadc->pdata->start_conversion(chan->channel);
527 	if (ret) {
528 		dev_err(gpadc->dev, "failed to start conversion\n");
529 		goto err;
530 	}
531 	/* wait for conversion to complete */
532 	timeout = wait_for_completion_interruptible_timeout(
533 				&gpadc->irq_complete, msecs_to_jiffies(5000));
534 	if (timeout == 0) {
535 		ret = -ETIMEDOUT;
536 		goto err;
537 	} else if (timeout < 0) {
538 		ret = -EINTR;
539 		goto err;
540 	}
541 
542 	switch (mask) {
543 	case IIO_CHAN_INFO_RAW:
544 		ret = twl6030_gpadc_get_raw(gpadc, chan->channel, val);
545 		ret = ret ? -EIO : IIO_VAL_INT;
546 		break;
547 
548 	case IIO_CHAN_INFO_PROCESSED:
549 		ret = twl6030_gpadc_get_processed(gpadc, chan->channel, val);
550 		ret = ret ? -EIO : IIO_VAL_INT;
551 		break;
552 
553 	default:
554 		break;
555 	}
556 err:
557 	mutex_unlock(&gpadc->lock);
558 
559 	return ret;
560 }
561 
562 /*
563  * The GPADC channels are calibrated using a two point calibration method.
564  * The channels measured with two known values: volt1 and volt2, and
565  * ideal corresponding output codes are known: code1, code2.
566  * The difference(d1, d2) between ideal and measured codes stored in trim
567  * registers.
568  * The goal is to find offset and gain of the real curve for each calibrated
569  * channel.
570  * gain: k = 1 + ((d2 - d1) / (x2 - x1))
571  * offset: b = d1 + (k - 1) * x1
572  */
573 static void twl6030_calibrate_channel(struct twl6030_gpadc_data *gpadc,
574 		int channel, int d1, int d2)
575 {
576 	int b, k, gain, x1, x2, i;
577 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
578 
579 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
580 
581 	/* Gain */
582 	gain = ((ideal[i].volt2 - ideal[i].volt1) * 1000) /
583 		(ideal[i].code2 - ideal[i].code1);
584 
585 	x1 = ideal[i].code1;
586 	x2 = ideal[i].code2;
587 
588 	/* k - real curve gain */
589 	k = 1000 + (((d2 - d1) * 1000) / (x2 - x1));
590 
591 	/* b - offset of the real curve gain */
592 	b = (d1 * 1000) - (k - 1000) * x1;
593 
594 	gpadc->twl6030_cal_tbl[i].gain = gain;
595 	gpadc->twl6030_cal_tbl[i].gain_error = k;
596 	gpadc->twl6030_cal_tbl[i].offset_error = b;
597 
598 	dev_dbg(gpadc->dev, "GPADC d1   for Chn: %d = %d\n", channel, d1);
599 	dev_dbg(gpadc->dev, "GPADC d2   for Chn: %d = %d\n", channel, d2);
600 	dev_dbg(gpadc->dev, "GPADC x1   for Chn: %d = %d\n", channel, x1);
601 	dev_dbg(gpadc->dev, "GPADC x2   for Chn: %d = %d\n", channel, x2);
602 	dev_dbg(gpadc->dev, "GPADC Gain for Chn: %d = %d\n", channel, gain);
603 	dev_dbg(gpadc->dev, "GPADC k    for Chn: %d = %d\n", channel, k);
604 	dev_dbg(gpadc->dev, "GPADC b    for Chn: %d = %d\n", channel, b);
605 }
606 
607 static inline int twl6030_gpadc_get_trim_offset(s8 d)
608 {
609 	/*
610 	 * XXX NOTE!
611 	 * bit 0 - sign, bit 7 - reserved, 6..1 - trim value
612 	 * though, the documentation states that trim value
613 	 * is absolute value, the correct conversion results are
614 	 * obtained if the value is interpreted as 2's complement.
615 	 */
616 	__u32 temp = ((d & 0x7f) >> 1) | ((d & 1) << 6);
617 
618 	return sign_extend32(temp, 6);
619 }
620 
621 static int twl6030_calibration(struct twl6030_gpadc_data *gpadc)
622 {
623 	int ret;
624 	int chn;
625 	u8 trim_regs[TWL6030_GPADC_NUM_TRIM_REGS];
626 	s8 d1, d2;
627 
628 	/*
629 	 * for calibration two measurements have been performed at
630 	 * factory, for some channels, during the production test and
631 	 * have been stored in registers. This two stored values are
632 	 * used to correct the measurements. The values represent
633 	 * offsets for the given input from the output on ideal curve.
634 	 */
635 	ret = twl_i2c_read(TWL6030_MODULE_ID2, trim_regs,
636 			TWL6030_GPADC_TRIM1, TWL6030_GPADC_NUM_TRIM_REGS);
637 	if (ret < 0) {
638 		dev_err(gpadc->dev, "calibration failed\n");
639 		return ret;
640 	}
641 
642 	for (chn = 0; chn < TWL6030_GPADC_MAX_CHANNELS; chn++) {
643 
644 		switch (chn) {
645 		case 0:
646 			d1 = trim_regs[0];
647 			d2 = trim_regs[1];
648 			break;
649 		case 1:
650 		case 3:
651 		case 4:
652 		case 5:
653 		case 6:
654 			d1 = trim_regs[4];
655 			d2 = trim_regs[5];
656 			break;
657 		case 2:
658 			d1 = trim_regs[12];
659 			d2 = trim_regs[13];
660 			break;
661 		case 7:
662 			d1 = trim_regs[6];
663 			d2 = trim_regs[7];
664 			break;
665 		case 8:
666 			d1 = trim_regs[2];
667 			d2 = trim_regs[3];
668 			break;
669 		case 9:
670 			d1 = trim_regs[8];
671 			d2 = trim_regs[9];
672 			break;
673 		case 10:
674 			d1 = trim_regs[10];
675 			d2 = trim_regs[11];
676 			break;
677 		case 14:
678 			d1 = trim_regs[14];
679 			d2 = trim_regs[15];
680 			break;
681 		default:
682 			continue;
683 		}
684 
685 		d1 = twl6030_gpadc_get_trim_offset(d1);
686 		d2 = twl6030_gpadc_get_trim_offset(d2);
687 
688 		twl6030_calibrate_channel(gpadc, chn, d1, d2);
689 	}
690 
691 	return 0;
692 }
693 
694 static int twl6032_get_trim_value(u8 *trim_regs, unsigned int reg0,
695 		unsigned int reg1, unsigned int mask0, unsigned int mask1,
696 		unsigned int shift0)
697 {
698 	int val;
699 
700 	val = (trim_regs[reg0] & mask0) << shift0;
701 	val |= (trim_regs[reg1] & mask1) >> 1;
702 	if (trim_regs[reg1] & 0x01)
703 		val = -val;
704 
705 	return val;
706 }
707 
708 static int twl6032_calibration(struct twl6030_gpadc_data *gpadc)
709 {
710 	int chn, d1 = 0, d2 = 0, temp;
711 	u8 trim_regs[TWL6030_GPADC_NUM_TRIM_REGS];
712 	int ret;
713 
714 	ret = twl_i2c_read(TWL6030_MODULE_ID2, trim_regs,
715 			TWL6030_GPADC_TRIM1, TWL6030_GPADC_NUM_TRIM_REGS);
716 	if (ret < 0) {
717 		dev_err(gpadc->dev, "calibration failed\n");
718 		return ret;
719 	}
720 
721 	/*
722 	 * Loop to calculate the value needed for returning voltages from
723 	 * GPADC not values.
724 	 *
725 	 * gain is calculated to 3 decimal places fixed point.
726 	 */
727 	for (chn = 0; chn < TWL6032_GPADC_MAX_CHANNELS; chn++) {
728 
729 		switch (chn) {
730 		case 0:
731 		case 1:
732 		case 2:
733 		case 3:
734 		case 4:
735 		case 5:
736 		case 6:
737 		case 11:
738 		case 14:
739 			d1 = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
740 								0x06, 2);
741 			d2 = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
742 								0x06, 2);
743 			break;
744 		case 8:
745 			temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
746 								0x06, 2);
747 			d1 = temp + twl6032_get_trim_value(trim_regs, 7, 6,
748 								0x18, 0x1E, 1);
749 
750 			temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3F,
751 								0x06, 2);
752 			d2 = temp + twl6032_get_trim_value(trim_regs, 9, 7,
753 								0x1F, 0x06, 2);
754 			break;
755 		case 9:
756 			temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
757 								0x06, 2);
758 			d1 = temp + twl6032_get_trim_value(trim_regs, 13, 11,
759 								0x18, 0x1E, 1);
760 
761 			temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
762 								0x06, 2);
763 			d2 = temp + twl6032_get_trim_value(trim_regs, 15, 13,
764 								0x1F, 0x06, 1);
765 			break;
766 		case 10:
767 			d1 = twl6032_get_trim_value(trim_regs, 10, 8, 0x0f,
768 								0x0E, 3);
769 			d2 = twl6032_get_trim_value(trim_regs, 14, 12, 0x0f,
770 								0x0E, 3);
771 			break;
772 		case 7:
773 		case 18:
774 			temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
775 								0x06, 2);
776 
777 			d1 = (trim_regs[4] & 0x7E) >> 1;
778 			if (trim_regs[4] & 0x01)
779 				d1 = -d1;
780 			d1 += temp;
781 
782 			temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
783 								0x06, 2);
784 
785 			d2 = (trim_regs[5] & 0xFE) >> 1;
786 			if (trim_regs[5] & 0x01)
787 				d2 = -d2;
788 
789 			d2 += temp;
790 			break;
791 		default:
792 			/* No data for other channels */
793 			continue;
794 		}
795 
796 		twl6030_calibrate_channel(gpadc, chn, d1, d2);
797 	}
798 
799 	return 0;
800 }
801 
802 #define TWL6030_GPADC_CHAN(chn, _type, chan_info) {	\
803 	.type = _type,					\
804 	.channel = chn,					\
805 	.info_mask_separate = BIT(chan_info),		\
806 	.indexed = 1,					\
807 }
808 
809 static const struct iio_chan_spec twl6030_gpadc_iio_channels[] = {
810 	TWL6030_GPADC_CHAN(0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
811 	TWL6030_GPADC_CHAN(1, IIO_TEMP, IIO_CHAN_INFO_RAW),
812 	TWL6030_GPADC_CHAN(2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
813 	TWL6030_GPADC_CHAN(3, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
814 	TWL6030_GPADC_CHAN(4, IIO_TEMP, IIO_CHAN_INFO_RAW),
815 	TWL6030_GPADC_CHAN(5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
816 	TWL6030_GPADC_CHAN(6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
817 	TWL6030_GPADC_CHAN(7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
818 	TWL6030_GPADC_CHAN(8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
819 	TWL6030_GPADC_CHAN(9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
820 	TWL6030_GPADC_CHAN(10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
821 	TWL6030_GPADC_CHAN(11, IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
822 	TWL6030_GPADC_CHAN(14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
823 };
824 
825 static const struct iio_chan_spec twl6032_gpadc_iio_channels[] = {
826 	TWL6030_GPADC_CHAN(0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
827 	TWL6030_GPADC_CHAN(1, IIO_TEMP, IIO_CHAN_INFO_RAW),
828 	TWL6030_GPADC_CHAN(2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
829 	TWL6030_GPADC_CHAN(3, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
830 	TWL6030_GPADC_CHAN(4, IIO_TEMP, IIO_CHAN_INFO_RAW),
831 	TWL6030_GPADC_CHAN(5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
832 	TWL6030_GPADC_CHAN(6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
833 	TWL6030_GPADC_CHAN(7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
834 	TWL6030_GPADC_CHAN(8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
835 	TWL6030_GPADC_CHAN(9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
836 	TWL6030_GPADC_CHAN(10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
837 	TWL6030_GPADC_CHAN(11, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
838 	TWL6030_GPADC_CHAN(14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
839 	TWL6030_GPADC_CHAN(17, IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
840 	TWL6030_GPADC_CHAN(18, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
841 };
842 
843 static const struct iio_info twl6030_gpadc_iio_info = {
844 	.read_raw = &twl6030_gpadc_read_raw,
845 };
846 
847 static const struct twl6030_gpadc_platform_data twl6030_pdata = {
848 	.iio_channels = twl6030_gpadc_iio_channels,
849 	.nchannels = TWL6030_GPADC_USED_CHANNELS,
850 	.ideal = twl6030_ideal,
851 	.start_conversion = twl6030_start_conversion,
852 	.channel_to_reg = twl6030_channel_to_reg,
853 	.calibrate = twl6030_calibration,
854 };
855 
856 static const struct twl6030_gpadc_platform_data twl6032_pdata = {
857 	.iio_channels = twl6032_gpadc_iio_channels,
858 	.nchannels = TWL6032_GPADC_USED_CHANNELS,
859 	.ideal = twl6032_ideal,
860 	.start_conversion = twl6032_start_conversion,
861 	.channel_to_reg = twl6032_channel_to_reg,
862 	.calibrate = twl6032_calibration,
863 };
864 
865 static const struct of_device_id of_twl6030_match_tbl[] = {
866 	{
867 		.compatible = "ti,twl6030-gpadc",
868 		.data = &twl6030_pdata,
869 	},
870 	{
871 		.compatible = "ti,twl6032-gpadc",
872 		.data = &twl6032_pdata,
873 	},
874 	{ /* end */ }
875 };
876 MODULE_DEVICE_TABLE(of, of_twl6030_match_tbl);
877 
878 static int twl6030_gpadc_probe(struct platform_device *pdev)
879 {
880 	struct device *dev = &pdev->dev;
881 	struct twl6030_gpadc_data *gpadc;
882 	const struct twl6030_gpadc_platform_data *pdata;
883 	struct iio_dev *indio_dev;
884 	int irq;
885 	int ret;
886 
887 	pdata = device_get_match_data(&pdev->dev);
888 	if (!pdata)
889 		return -EINVAL;
890 
891 	indio_dev = devm_iio_device_alloc(dev, sizeof(*gpadc));
892 	if (!indio_dev)
893 		return -ENOMEM;
894 
895 	gpadc = iio_priv(indio_dev);
896 
897 	gpadc->twl6030_cal_tbl = devm_kcalloc(dev,
898 					pdata->nchannels,
899 					sizeof(*gpadc->twl6030_cal_tbl),
900 					GFP_KERNEL);
901 	if (!gpadc->twl6030_cal_tbl)
902 		return -ENOMEM;
903 
904 	gpadc->dev = dev;
905 	gpadc->pdata = pdata;
906 
907 	platform_set_drvdata(pdev, indio_dev);
908 	mutex_init(&gpadc->lock);
909 	init_completion(&gpadc->irq_complete);
910 
911 	ret = pdata->calibrate(gpadc);
912 	if (ret < 0) {
913 		dev_err(dev, "failed to read calibration registers\n");
914 		return ret;
915 	}
916 
917 	irq = platform_get_irq(pdev, 0);
918 	if (irq < 0)
919 		return irq;
920 
921 	ret = devm_request_threaded_irq(dev, irq, NULL,
922 				twl6030_gpadc_irq_handler,
923 				IRQF_ONESHOT, "twl6030_gpadc", indio_dev);
924 	if (ret)
925 		return ret;
926 
927 	ret = twl6030_gpadc_enable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK);
928 	if (ret < 0) {
929 		dev_err(dev, "failed to enable GPADC interrupt\n");
930 		return ret;
931 	}
932 
933 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS,
934 					TWL6030_REG_TOGGLE1);
935 	if (ret < 0) {
936 		dev_err(dev, "failed to enable GPADC module\n");
937 		return ret;
938 	}
939 
940 	ret = twl_i2c_write_u8(TWL_MODULE_USB, VBUS_MEAS, USB_VBUS_CTRL_SET);
941 	if (ret < 0) {
942 		dev_err(dev, "failed to wire up inputs\n");
943 		return ret;
944 	}
945 
946 	ret = twl_i2c_write_u8(TWL_MODULE_USB, ID_MEAS, USB_ID_CTRL_SET);
947 	if (ret < 0) {
948 		dev_err(dev, "failed to wire up inputs\n");
949 		return ret;
950 	}
951 
952 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID0,
953 				VBAT_MEAS | BB_MEAS | VAC_MEAS,
954 				TWL6030_MISC1);
955 	if (ret < 0) {
956 		dev_err(dev, "failed to wire up inputs\n");
957 		return ret;
958 	}
959 
960 	indio_dev->name = DRIVER_NAME;
961 	indio_dev->info = &twl6030_gpadc_iio_info;
962 	indio_dev->modes = INDIO_DIRECT_MODE;
963 	indio_dev->channels = pdata->iio_channels;
964 	indio_dev->num_channels = pdata->nchannels;
965 
966 	return iio_device_register(indio_dev);
967 }
968 
969 static void twl6030_gpadc_remove(struct platform_device *pdev)
970 {
971 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
972 
973 	twl6030_gpadc_disable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK);
974 	iio_device_unregister(indio_dev);
975 }
976 
977 static int twl6030_gpadc_suspend(struct device *pdev)
978 {
979 	int ret;
980 
981 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCR,
982 				TWL6030_REG_TOGGLE1);
983 	if (ret)
984 		dev_err(pdev, "error resetting GPADC (%d)!\n", ret);
985 
986 	return 0;
987 };
988 
989 static int twl6030_gpadc_resume(struct device *pdev)
990 {
991 	int ret;
992 
993 	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS,
994 				TWL6030_REG_TOGGLE1);
995 	if (ret)
996 		dev_err(pdev, "error setting GPADC (%d)!\n", ret);
997 
998 	return 0;
999 };
1000 
1001 static DEFINE_SIMPLE_DEV_PM_OPS(twl6030_gpadc_pm_ops, twl6030_gpadc_suspend,
1002 				twl6030_gpadc_resume);
1003 
1004 static struct platform_driver twl6030_gpadc_driver = {
1005 	.probe		= twl6030_gpadc_probe,
1006 	.remove_new	= twl6030_gpadc_remove,
1007 	.driver		= {
1008 		.name	= DRIVER_NAME,
1009 		.pm	= pm_sleep_ptr(&twl6030_gpadc_pm_ops),
1010 		.of_match_table = of_twl6030_match_tbl,
1011 	},
1012 };
1013 
1014 module_platform_driver(twl6030_gpadc_driver);
1015 
1016 MODULE_ALIAS("platform:" DRIVER_NAME);
1017 MODULE_AUTHOR("Balaji T K <balajitk@ti.com>");
1018 MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
1019 MODULE_AUTHOR("Oleksandr Kozaruk <oleksandr.kozaruk@ti.com");
1020 MODULE_DESCRIPTION("twl6030 ADC driver");
1021 MODULE_LICENSE("GPL");
1022