xref: /openbmc/linux/drivers/iio/adc/twl6030-gpadc.c (revision 161f4089)
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/init.h>
32 #include <linux/interrupt.h>
33 #include <linux/kernel.h>
34 #include <linux/module.h>
35 #include <linux/platform_device.h>
36 #include <linux/of_platform.h>
37 #include <linux/i2c/twl.h>
38 #include <linux/iio/iio.h>
39 #include <linux/iio/sysfs.h>
40 
41 #define DRIVER_NAME		"twl6030_gpadc"
42 
43 /*
44  * twl6030 per TRM has 17 channels, and twl6032 has 19 channels
45  * 2 test network channels are not used,
46  * 2 die temperature channels are not used either, as it is not
47  * defined how to convert ADC value to temperature
48  */
49 #define TWL6030_GPADC_USED_CHANNELS		13
50 #define TWL6030_GPADC_MAX_CHANNELS		15
51 #define TWL6032_GPADC_USED_CHANNELS		15
52 #define TWL6032_GPADC_MAX_CHANNELS		19
53 #define TWL6030_GPADC_NUM_TRIM_REGS		16
54 
55 #define TWL6030_GPADC_CTRL_P1			0x05
56 
57 #define TWL6032_GPADC_GPSELECT_ISB		0x07
58 #define TWL6032_GPADC_CTRL_P1			0x08
59 
60 #define TWL6032_GPADC_GPCH0_LSB			0x0d
61 #define TWL6032_GPADC_GPCH0_MSB			0x0e
62 
63 #define TWL6030_GPADC_CTRL_P1_SP1		BIT(3)
64 
65 #define TWL6030_GPADC_GPCH0_LSB			(0x29)
66 
67 #define TWL6030_GPADC_RT_SW1_EOC_MASK		BIT(5)
68 
69 #define TWL6030_GPADC_TRIM1			0xCD
70 
71 #define TWL6030_REG_TOGGLE1			0x90
72 #define TWL6030_GPADCS				BIT(1)
73 #define TWL6030_GPADCR				BIT(0)
74 
75 /**
76  * struct twl6030_chnl_calib - channel calibration
77  * @gain:		slope coefficient for ideal curve
78  * @gain_error:		gain error
79  * @offset_error:	offset of the real curve
80  */
81 struct twl6030_chnl_calib {
82 	s32 gain;
83 	s32 gain_error;
84 	s32 offset_error;
85 };
86 
87 /**
88  * struct twl6030_ideal_code - GPADC calibration parameters
89  * GPADC is calibrated in two points: close to the beginning and
90  * to the and of the measurable input range
91  *
92  * @channel:	channel number
93  * @code1:	ideal code for the input at the beginning
94  * @code2:	ideal code for at the end of the range
95  * @volt1:	voltage input at the beginning(low voltage)
96  * @volt2:	voltage input at the end(high voltage)
97  */
98 struct twl6030_ideal_code {
99 	int channel;
100 	u16 code1;
101 	u16 code2;
102 	u16 volt1;
103 	u16 volt2;
104 };
105 
106 struct twl6030_gpadc_data;
107 
108 /**
109  * struct twl6030_gpadc_platform_data - platform specific data
110  * @nchannels:		number of GPADC channels
111  * @iio_channels:	iio channels
112  * @twl6030_ideal:	pointer to calibration parameters
113  * @start_conversion:	pointer to ADC start conversion function
114  * @channel_to_reg	pointer to ADC function to convert channel to
115  *			register address for reading conversion result
116  * @calibrate:		pointer to calibration function
117  */
118 struct twl6030_gpadc_platform_data {
119 	const int nchannels;
120 	const struct iio_chan_spec *iio_channels;
121 	const struct twl6030_ideal_code *ideal;
122 	int (*start_conversion)(int channel);
123 	u8 (*channel_to_reg)(int channel);
124 	int (*calibrate)(struct twl6030_gpadc_data *gpadc);
125 };
126 
127 /**
128  * struct twl6030_gpadc_data - GPADC data
129  * @dev:		device pointer
130  * @lock:		mutual exclusion lock for the structure
131  * @irq_complete:	completion to signal end of conversion
132  * @twl6030_cal_tbl:	pointer to calibration data for each
133  *			channel with gain error and offset
134  * @pdata:		pointer to device specific data
135  */
136 struct twl6030_gpadc_data {
137 	struct device	*dev;
138 	struct mutex	lock;
139 	struct completion	irq_complete;
140 	struct twl6030_chnl_calib	*twl6030_cal_tbl;
141 	const struct twl6030_gpadc_platform_data *pdata;
142 };
143 
144 /*
145  * channels 11, 12, 13, 15 and 16 have no calibration data
146  * calibration offset is same for channels 1, 3, 4, 5
147  *
148  * The data is taken from GPADC_TRIM registers description.
149  * GPADC_TRIM registers keep difference between the code measured
150  * at volt1 and volt2 input voltages and corresponding code1 and code2
151  */
152 static const struct twl6030_ideal_code
153 	twl6030_ideal[TWL6030_GPADC_USED_CHANNELS] = {
154 	[0] = { /* ch 0, external, battery type, resistor value */
155 		.channel = 0,
156 		.code1 = 116,
157 		.code2 = 745,
158 		.volt1 = 141,
159 		.volt2 = 910,
160 	},
161 	[1] = { /* ch 1, external, battery temperature, NTC resistor value */
162 		.channel = 1,
163 		.code1 = 82,
164 		.code2 = 900,
165 		.volt1 = 100,
166 		.volt2 = 1100,
167 	},
168 	[2] = { /* ch 2, external, audio accessory/general purpose */
169 		.channel = 2,
170 		.code1 = 55,
171 		.code2 = 818,
172 		.volt1 = 101,
173 		.volt2 = 1499,
174 	},
175 	[3] = { /* ch 3, external, general purpose */
176 		.channel = 3,
177 		.code1 = 82,
178 		.code2 = 900,
179 		.volt1 = 100,
180 		.volt2 = 1100,
181 	},
182 	[4] = { /* ch 4, external, temperature measurement/general purpose */
183 		.channel = 4,
184 		.code1 = 82,
185 		.code2 = 900,
186 		.volt1 = 100,
187 		.volt2 = 1100,
188 	},
189 	[5] = { /* ch 5, external, general purpose */
190 		.channel = 5,
191 		.code1 = 82,
192 		.code2 = 900,
193 		.volt1 = 100,
194 		.volt2 = 1100,
195 	},
196 	[6] = { /* ch 6, external, general purpose */
197 		.channel = 6,
198 		.code1 = 82,
199 		.code2 = 900,
200 		.volt1 = 100,
201 		.volt2 = 1100,
202 	},
203 	[7] = { /* ch 7, internal, main battery */
204 		.channel = 7,
205 		.code1 = 614,
206 		.code2 = 941,
207 		.volt1 = 3001,
208 		.volt2 = 4599,
209 	},
210 	[8] = { /* ch 8, internal, backup battery */
211 		.channel = 8,
212 		.code1 = 82,
213 		.code2 = 688,
214 		.volt1 = 501,
215 		.volt2 = 4203,
216 	},
217 	[9] = { /* ch 9, internal, external charger input */
218 		.channel = 9,
219 		.code1 = 182,
220 		.code2 = 818,
221 		.volt1 = 2001,
222 		.volt2 = 8996,
223 	},
224 	[10] = { /* ch 10, internal, VBUS */
225 		.channel = 10,
226 		.code1 = 149,
227 		.code2 = 818,
228 		.volt1 = 1001,
229 		.volt2 = 5497,
230 	},
231 	[11] = { /* ch 11, internal, VBUS charging current */
232 		.channel = 11,
233 	},
234 		/* ch 12, internal, Die temperature */
235 		/* ch 13, internal, Die temperature */
236 	[12] = { /* ch 14, internal, USB ID line */
237 		.channel = 14,
238 		.code1 = 48,
239 		.code2 = 714,
240 		.volt1 = 323,
241 		.volt2 = 4800,
242 	},
243 };
244 
245 static const struct twl6030_ideal_code
246 			twl6032_ideal[TWL6032_GPADC_USED_CHANNELS] = {
247 	[0] = { /* ch 0, external, battery type, resistor value */
248 		.channel = 0,
249 		.code1 = 1441,
250 		.code2 = 3276,
251 		.volt1 = 440,
252 		.volt2 = 1000,
253 	},
254 	[1] = { /* ch 1, external, battery temperature, NTC resistor value */
255 		.channel = 1,
256 		.code1 = 1441,
257 		.code2 = 3276,
258 		.volt1 = 440,
259 		.volt2 = 1000,
260 	},
261 	[2] = { /* ch 2, external, audio accessory/general purpose */
262 		.channel = 2,
263 		.code1 = 1441,
264 		.code2 = 3276,
265 		.volt1 = 660,
266 		.volt2 = 1500,
267 	},
268 	[3] = { /* ch 3, external, temperature with external diode/general
269 								purpose */
270 		.channel = 3,
271 		.code1 = 1441,
272 		.code2 = 3276,
273 		.volt1 = 440,
274 		.volt2 = 1000,
275 	},
276 	[4] = { /* ch 4, external, temperature measurement/general purpose */
277 		.channel = 4,
278 		.code1 = 1441,
279 		.code2 = 3276,
280 		.volt1 = 440,
281 		.volt2 = 1000,
282 	},
283 	[5] = { /* ch 5, external, general purpose */
284 		.channel = 5,
285 		.code1 = 1441,
286 		.code2 = 3276,
287 		.volt1 = 440,
288 		.volt2 = 1000,
289 	},
290 	[6] = { /* ch 6, external, general purpose */
291 		.channel = 6,
292 		.code1 = 1441,
293 		.code2 = 3276,
294 		.volt1 = 440,
295 		.volt2 = 1000,
296 	},
297 	[7] = { /* ch7, internal, system supply */
298 		.channel = 7,
299 		.code1 = 1441,
300 		.code2 = 3276,
301 		.volt1 = 2200,
302 		.volt2 = 5000,
303 	},
304 	[8] = { /* ch8, internal, backup battery */
305 		.channel = 8,
306 		.code1 = 1441,
307 		.code2 = 3276,
308 		.volt1 = 2200,
309 		.volt2 = 5000,
310 	},
311 	[9] = { /* ch 9, internal, external charger input */
312 		.channel = 9,
313 		.code1 = 1441,
314 		.code2 = 3276,
315 		.volt1 = 3960,
316 		.volt2 = 9000,
317 	},
318 	[10] = { /* ch10, internal, VBUS */
319 		.channel = 10,
320 		.code1 = 150,
321 		.code2 = 751,
322 		.volt1 = 1000,
323 		.volt2 = 5000,
324 	},
325 	[11] = { /* ch 11, internal, VBUS DC-DC output current */
326 		.channel = 11,
327 		.code1 = 1441,
328 		.code2 = 3276,
329 		.volt1 = 660,
330 		.volt2 = 1500,
331 	},
332 		/* ch 12, internal, Die temperature */
333 		/* ch 13, internal, Die temperature */
334 	[12] = { /* ch 14, internal, USB ID line */
335 		.channel = 14,
336 		.code1 = 1441,
337 		.code2 = 3276,
338 		.volt1 = 2420,
339 		.volt2 = 5500,
340 	},
341 		/* ch 15, internal, test network */
342 		/* ch 16, internal, test network */
343 	[13] = { /* ch 17, internal, battery charging current */
344 		.channel = 17,
345 	},
346 	[14] = { /* ch 18, internal, battery voltage */
347 		.channel = 18,
348 		.code1 = 1441,
349 		.code2 = 3276,
350 		.volt1 = 2200,
351 		.volt2 = 5000,
352 	},
353 };
354 
355 static inline int twl6030_gpadc_write(u8 reg, u8 val)
356 {
357 	return twl_i2c_write_u8(TWL6030_MODULE_GPADC, val, reg);
358 }
359 
360 static inline int twl6030_gpadc_read(u8 reg, u8 *val)
361 {
362 
363 	return twl_i2c_read(TWL6030_MODULE_GPADC, val, reg, 2);
364 }
365 
366 static int twl6030_gpadc_enable_irq(u8 mask)
367 {
368 	int ret;
369 
370 	ret = twl6030_interrupt_unmask(mask, REG_INT_MSK_LINE_B);
371 	if (ret < 0)
372 		return ret;
373 
374 	ret = twl6030_interrupt_unmask(mask, REG_INT_MSK_STS_B);
375 
376 	return ret;
377 }
378 
379 static void twl6030_gpadc_disable_irq(u8 mask)
380 {
381 	twl6030_interrupt_mask(mask, REG_INT_MSK_LINE_B);
382 	twl6030_interrupt_mask(mask, REG_INT_MSK_STS_B);
383 }
384 
385 static irqreturn_t twl6030_gpadc_irq_handler(int irq, void *indio_dev)
386 {
387 	struct twl6030_gpadc_data *gpadc = iio_priv(indio_dev);
388 
389 	complete(&gpadc->irq_complete);
390 
391 	return IRQ_HANDLED;
392 }
393 
394 static int twl6030_start_conversion(int channel)
395 {
396 	return twl6030_gpadc_write(TWL6030_GPADC_CTRL_P1,
397 					TWL6030_GPADC_CTRL_P1_SP1);
398 }
399 
400 static int twl6032_start_conversion(int channel)
401 {
402 	int ret;
403 
404 	ret = twl6030_gpadc_write(TWL6032_GPADC_GPSELECT_ISB, channel);
405 	if (ret)
406 		return ret;
407 
408 	return twl6030_gpadc_write(TWL6032_GPADC_CTRL_P1,
409 						TWL6030_GPADC_CTRL_P1_SP1);
410 }
411 
412 static u8 twl6030_channel_to_reg(int channel)
413 {
414 	return TWL6030_GPADC_GPCH0_LSB + 2 * channel;
415 }
416 
417 static u8 twl6032_channel_to_reg(int channel)
418 {
419 	/*
420 	 * for any prior chosen channel, when the conversion is ready
421 	 * the result is avalable in GPCH0_LSB, GPCH0_MSB.
422 	 */
423 
424 	return TWL6032_GPADC_GPCH0_LSB;
425 }
426 
427 static int twl6030_gpadc_lookup(const struct twl6030_ideal_code *ideal,
428 		int channel, int size)
429 {
430 	int i;
431 
432 	for (i = 0; i < size; i++)
433 		if (ideal[i].channel == channel)
434 			break;
435 
436 	return i;
437 }
438 
439 static int twl6030_channel_calibrated(const struct twl6030_gpadc_platform_data
440 		*pdata, int channel)
441 {
442 	const struct twl6030_ideal_code *ideal = pdata->ideal;
443 	int i;
444 
445 	i = twl6030_gpadc_lookup(ideal, channel, pdata->nchannels);
446 	/* not calibrated channels have 0 in all structure members */
447 	return pdata->ideal[i].code2;
448 }
449 
450 static int twl6030_gpadc_make_correction(struct twl6030_gpadc_data *gpadc,
451 		int channel, int raw_code)
452 {
453 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
454 	int corrected_code;
455 	int i;
456 
457 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
458 	corrected_code = ((raw_code * 1000) -
459 		gpadc->twl6030_cal_tbl[i].offset_error) /
460 		gpadc->twl6030_cal_tbl[i].gain_error;
461 
462 	return corrected_code;
463 }
464 
465 static int twl6030_gpadc_get_raw(struct twl6030_gpadc_data *gpadc,
466 		int channel, int *res)
467 {
468 	u8 reg = gpadc->pdata->channel_to_reg(channel);
469 	__le16 val;
470 	int raw_code;
471 	int ret;
472 
473 	ret = twl6030_gpadc_read(reg, (u8 *)&val);
474 	if (ret) {
475 		dev_dbg(gpadc->dev, "unable to read register 0x%X\n", reg);
476 		return ret;
477 	}
478 
479 	raw_code = le16_to_cpu(val);
480 	dev_dbg(gpadc->dev, "GPADC raw code: %d", raw_code);
481 
482 	if (twl6030_channel_calibrated(gpadc->pdata, channel))
483 		*res = twl6030_gpadc_make_correction(gpadc, channel, raw_code);
484 	else
485 		*res = raw_code;
486 
487 	return ret;
488 }
489 
490 static int twl6030_gpadc_get_processed(struct twl6030_gpadc_data *gpadc,
491 		int channel, int *val)
492 {
493 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
494 	int corrected_code;
495 	int channel_value;
496 	int i;
497 	int ret;
498 
499 	ret = twl6030_gpadc_get_raw(gpadc, channel, &corrected_code);
500 	if (ret)
501 		return ret;
502 
503 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
504 	channel_value = corrected_code *
505 			gpadc->twl6030_cal_tbl[i].gain;
506 
507 	/* Shift back into mV range */
508 	channel_value /= 1000;
509 
510 	dev_dbg(gpadc->dev, "GPADC corrected code: %d", corrected_code);
511 	dev_dbg(gpadc->dev, "GPADC value: %d", channel_value);
512 
513 	*val = channel_value;
514 
515 	return ret;
516 }
517 
518 static int twl6030_gpadc_read_raw(struct iio_dev *indio_dev,
519 			     const struct iio_chan_spec *chan,
520 			     int *val, int *val2, long mask)
521 {
522 	struct twl6030_gpadc_data *gpadc = iio_priv(indio_dev);
523 	int ret;
524 	long timeout;
525 
526 	mutex_lock(&gpadc->lock);
527 
528 	ret = gpadc->pdata->start_conversion(chan->channel);
529 	if (ret) {
530 		dev_err(gpadc->dev, "failed to start conversion\n");
531 		goto err;
532 	}
533 	/* wait for conversion to complete */
534 	timeout = wait_for_completion_interruptible_timeout(
535 				&gpadc->irq_complete, msecs_to_jiffies(5000));
536 	if (timeout == 0) {
537 		ret = -ETIMEDOUT;
538 		goto err;
539 	} else if (timeout < 0) {
540 		ret = -EINTR;
541 		goto err;
542 	}
543 
544 	switch (mask) {
545 	case IIO_CHAN_INFO_RAW:
546 		ret = twl6030_gpadc_get_raw(gpadc, chan->channel, val);
547 		ret = ret ? -EIO : IIO_VAL_INT;
548 		break;
549 
550 	case IIO_CHAN_INFO_PROCESSED:
551 		ret = twl6030_gpadc_get_processed(gpadc, chan->channel, val);
552 		ret = ret ? -EIO : IIO_VAL_INT;
553 		break;
554 
555 	default:
556 		break;
557 	}
558 err:
559 	mutex_unlock(&gpadc->lock);
560 
561 	return ret;
562 }
563 
564 /*
565  * The GPADC channels are calibrated using a two point calibration method.
566  * The channels measured with two known values: volt1 and volt2, and
567  * ideal corresponding output codes are known: code1, code2.
568  * The difference(d1, d2) between ideal and measured codes stored in trim
569  * registers.
570  * The goal is to find offset and gain of the real curve for each calibrated
571  * channel.
572  * gain: k = 1 + ((d2 - d1) / (x2 - x1))
573  * offset: b = d1 + (k - 1) * x1
574  */
575 static void twl6030_calibrate_channel(struct twl6030_gpadc_data *gpadc,
576 		int channel, int d1, int d2)
577 {
578 	int b, k, gain, x1, x2, i;
579 	const struct twl6030_ideal_code *ideal = gpadc->pdata->ideal;
580 
581 	i = twl6030_gpadc_lookup(ideal, channel, gpadc->pdata->nchannels);
582 
583 	/* Gain */
584 	gain = ((ideal[i].volt2 - ideal[i].volt1) * 1000) /
585 		(ideal[i].code2 - ideal[i].code1);
586 
587 	x1 = ideal[i].code1;
588 	x2 = ideal[i].code2;
589 
590 	/* k - real curve gain */
591 	k = 1000 + (((d2 - d1) * 1000) / (x2 - x1));
592 
593 	/* b - offset of the real curve gain */
594 	b = (d1 * 1000) - (k - 1000) * x1;
595 
596 	gpadc->twl6030_cal_tbl[i].gain = gain;
597 	gpadc->twl6030_cal_tbl[i].gain_error = k;
598 	gpadc->twl6030_cal_tbl[i].offset_error = b;
599 
600 	dev_dbg(gpadc->dev, "GPADC d1   for Chn: %d = %d\n", channel, d1);
601 	dev_dbg(gpadc->dev, "GPADC d2   for Chn: %d = %d\n", channel, d2);
602 	dev_dbg(gpadc->dev, "GPADC x1   for Chn: %d = %d\n", channel, x1);
603 	dev_dbg(gpadc->dev, "GPADC x2   for Chn: %d = %d\n", channel, x2);
604 	dev_dbg(gpadc->dev, "GPADC Gain for Chn: %d = %d\n", channel, gain);
605 	dev_dbg(gpadc->dev, "GPADC k    for Chn: %d = %d\n", channel, k);
606 	dev_dbg(gpadc->dev, "GPADC b    for Chn: %d = %d\n", channel, b);
607 }
608 
609 static inline int twl6030_gpadc_get_trim_offset(s8 d)
610 {
611 	/*
612 	 * XXX NOTE!
613 	 * bit 0 - sign, bit 7 - reserved, 6..1 - trim value
614 	 * though, the documentation states that trim value
615 	 * is absolute value, the correct conversion results are
616 	 * obtained if the value is interpreted as 2's complement.
617 	 */
618 	__u32 temp = ((d & 0x7f) >> 1) | ((d & 1) << 6);
619 
620 	return sign_extend32(temp, 6);
621 }
622 
623 static int twl6030_calibration(struct twl6030_gpadc_data *gpadc)
624 {
625 	int ret;
626 	int chn;
627 	u8 trim_regs[TWL6030_GPADC_NUM_TRIM_REGS];
628 	s8 d1, d2;
629 
630 	/*
631 	 * for calibration two measurements have been performed at
632 	 * factory, for some channels, during the production test and
633 	 * have been stored in registers. This two stored values are
634 	 * used to correct the measurements. The values represent
635 	 * offsets for the given input from the output on ideal curve.
636 	 */
637 	ret = twl_i2c_read(TWL6030_MODULE_ID2, trim_regs,
638 			TWL6030_GPADC_TRIM1, TWL6030_GPADC_NUM_TRIM_REGS);
639 	if (ret < 0) {
640 		dev_err(gpadc->dev, "calibration failed\n");
641 		return ret;
642 	}
643 
644 	for (chn = 0; chn < TWL6030_GPADC_MAX_CHANNELS; chn++) {
645 
646 		switch (chn) {
647 		case 0:
648 			d1 = trim_regs[0];
649 			d2 = trim_regs[1];
650 			break;
651 		case 1:
652 		case 3:
653 		case 4:
654 		case 5:
655 		case 6:
656 			d1 = trim_regs[4];
657 			d2 = trim_regs[5];
658 			break;
659 		case 2:
660 			d1 = trim_regs[12];
661 			d2 = trim_regs[13];
662 			break;
663 		case 7:
664 			d1 = trim_regs[6];
665 			d2 = trim_regs[7];
666 			break;
667 		case 8:
668 			d1 = trim_regs[2];
669 			d2 = trim_regs[3];
670 			break;
671 		case 9:
672 			d1 = trim_regs[8];
673 			d2 = trim_regs[9];
674 			break;
675 		case 10:
676 			d1 = trim_regs[10];
677 			d2 = trim_regs[11];
678 			break;
679 		case 14:
680 			d1 = trim_regs[14];
681 			d2 = trim_regs[15];
682 			break;
683 		default:
684 			continue;
685 		}
686 
687 		d1 = twl6030_gpadc_get_trim_offset(d1);
688 		d2 = twl6030_gpadc_get_trim_offset(d2);
689 
690 		twl6030_calibrate_channel(gpadc, chn, d1, d2);
691 	}
692 
693 	return 0;
694 }
695 
696 static int twl6032_get_trim_value(u8 *trim_regs, unsigned int reg0,
697 		unsigned int reg1, unsigned int mask0, unsigned int mask1,
698 		unsigned int shift0)
699 {
700 	int val;
701 
702 	val = (trim_regs[reg0] & mask0) << shift0;
703 	val |= (trim_regs[reg1] & mask1) >> 1;
704 	if (trim_regs[reg1] & 0x01)
705 		val = -val;
706 
707 	return val;
708 }
709 
710 static int twl6032_calibration(struct twl6030_gpadc_data *gpadc)
711 {
712 	int chn, d1 = 0, d2 = 0, temp;
713 	u8 trim_regs[TWL6030_GPADC_NUM_TRIM_REGS];
714 	int ret;
715 
716 	ret = twl_i2c_read(TWL6030_MODULE_ID2, trim_regs,
717 			TWL6030_GPADC_TRIM1, TWL6030_GPADC_NUM_TRIM_REGS);
718 	if (ret < 0) {
719 		dev_err(gpadc->dev, "calibration failed\n");
720 		return ret;
721 	}
722 
723 	/*
724 	 * Loop to calculate the value needed for returning voltages from
725 	 * GPADC not values.
726 	 *
727 	 * gain is calculated to 3 decimal places fixed point.
728 	 */
729 	for (chn = 0; chn < TWL6032_GPADC_MAX_CHANNELS; chn++) {
730 
731 		switch (chn) {
732 		case 0:
733 		case 1:
734 		case 2:
735 		case 3:
736 		case 4:
737 		case 5:
738 		case 6:
739 		case 11:
740 		case 14:
741 			d1 = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
742 								0x06, 2);
743 			d2 = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
744 								0x06, 2);
745 			break;
746 		case 8:
747 			temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
748 								0x06, 2);
749 			d1 = temp + twl6032_get_trim_value(trim_regs, 7, 6,
750 								0x18, 0x1E, 1);
751 
752 			temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3F,
753 								0x06, 2);
754 			d2 = temp + twl6032_get_trim_value(trim_regs, 9, 7,
755 								0x1F, 0x06, 2);
756 			break;
757 		case 9:
758 			temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
759 								0x06, 2);
760 			d1 = temp + twl6032_get_trim_value(trim_regs, 13, 11,
761 								0x18, 0x1E, 1);
762 
763 			temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
764 								0x06, 2);
765 			d2 = temp + twl6032_get_trim_value(trim_regs, 15, 13,
766 								0x1F, 0x06, 1);
767 			break;
768 		case 10:
769 			d1 = twl6032_get_trim_value(trim_regs, 10, 8, 0x0f,
770 								0x0E, 3);
771 			d2 = twl6032_get_trim_value(trim_regs, 14, 12, 0x0f,
772 								0x0E, 3);
773 			break;
774 		case 7:
775 		case 18:
776 			temp = twl6032_get_trim_value(trim_regs, 2, 0, 0x1f,
777 								0x06, 2);
778 
779 			d1 = (trim_regs[4] & 0x7E) >> 1;
780 			if (trim_regs[4] & 0x01)
781 				d1 = -d1;
782 			d1 += temp;
783 
784 			temp = twl6032_get_trim_value(trim_regs, 3, 1, 0x3f,
785 								0x06, 2);
786 
787 			d2 = (trim_regs[5] & 0xFE) >> 1;
788 			if (trim_regs[5] & 0x01)
789 				d2 = -d2;
790 
791 			d2 += temp;
792 			break;
793 		default:
794 			/* No data for other channels */
795 			continue;
796 		}
797 
798 		twl6030_calibrate_channel(gpadc, chn, d1, d2);
799 	}
800 
801 	return 0;
802 }
803 
804 #define TWL6030_GPADC_CHAN(chn, _type, chan_info) {	\
805 	.type = _type,					\
806 	.channel = chn,					\
807 	.info_mask_separate = BIT(chan_info),		\
808 	.indexed = 1,					\
809 }
810 
811 static const struct iio_chan_spec twl6030_gpadc_iio_channels[] = {
812 	TWL6030_GPADC_CHAN(0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
813 	TWL6030_GPADC_CHAN(1, IIO_TEMP, IIO_CHAN_INFO_RAW),
814 	TWL6030_GPADC_CHAN(2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
815 	TWL6030_GPADC_CHAN(3, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
816 	TWL6030_GPADC_CHAN(4, IIO_TEMP, IIO_CHAN_INFO_RAW),
817 	TWL6030_GPADC_CHAN(5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
818 	TWL6030_GPADC_CHAN(6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
819 	TWL6030_GPADC_CHAN(7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
820 	TWL6030_GPADC_CHAN(8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
821 	TWL6030_GPADC_CHAN(9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
822 	TWL6030_GPADC_CHAN(10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
823 	TWL6030_GPADC_CHAN(11, IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
824 	TWL6030_GPADC_CHAN(14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
825 };
826 
827 static const struct iio_chan_spec twl6032_gpadc_iio_channels[] = {
828 	TWL6030_GPADC_CHAN(0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
829 	TWL6030_GPADC_CHAN(1, IIO_TEMP, IIO_CHAN_INFO_RAW),
830 	TWL6030_GPADC_CHAN(2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
831 	TWL6030_GPADC_CHAN(3, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
832 	TWL6030_GPADC_CHAN(4, IIO_TEMP, IIO_CHAN_INFO_RAW),
833 	TWL6030_GPADC_CHAN(5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
834 	TWL6030_GPADC_CHAN(6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
835 	TWL6030_GPADC_CHAN(7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
836 	TWL6030_GPADC_CHAN(8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
837 	TWL6030_GPADC_CHAN(9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
838 	TWL6030_GPADC_CHAN(10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
839 	TWL6030_GPADC_CHAN(11, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
840 	TWL6030_GPADC_CHAN(14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
841 	TWL6030_GPADC_CHAN(17, IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
842 	TWL6030_GPADC_CHAN(18, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
843 };
844 
845 static const struct iio_info twl6030_gpadc_iio_info = {
846 	.read_raw = &twl6030_gpadc_read_raw,
847 	.driver_module = THIS_MODULE,
848 };
849 
850 static const struct twl6030_gpadc_platform_data twl6030_pdata = {
851 	.iio_channels = twl6030_gpadc_iio_channels,
852 	.nchannels = TWL6030_GPADC_USED_CHANNELS,
853 	.ideal = twl6030_ideal,
854 	.start_conversion = twl6030_start_conversion,
855 	.channel_to_reg = twl6030_channel_to_reg,
856 	.calibrate = twl6030_calibration,
857 };
858 
859 static const struct twl6030_gpadc_platform_data twl6032_pdata = {
860 	.iio_channels = twl6032_gpadc_iio_channels,
861 	.nchannels = TWL6032_GPADC_USED_CHANNELS,
862 	.ideal = twl6032_ideal,
863 	.start_conversion = twl6032_start_conversion,
864 	.channel_to_reg = twl6032_channel_to_reg,
865 	.calibrate = twl6032_calibration,
866 };
867 
868 static const struct of_device_id of_twl6030_match_tbl[] = {
869 	{
870 		.compatible = "ti,twl6030-gpadc",
871 		.data = &twl6030_pdata,
872 	},
873 	{
874 		.compatible = "ti,twl6032-gpadc",
875 		.data = &twl6032_pdata,
876 	},
877 	{ /* end */ }
878 };
879 
880 static int twl6030_gpadc_probe(struct platform_device *pdev)
881 {
882 	struct device *dev = &pdev->dev;
883 	struct twl6030_gpadc_data *gpadc;
884 	const struct twl6030_gpadc_platform_data *pdata;
885 	const struct of_device_id *match;
886 	struct iio_dev *indio_dev;
887 	int irq;
888 	int ret;
889 
890 	match = of_match_device(of_twl6030_match_tbl, dev);
891 	if (!match)
892 		return -EINVAL;
893 
894 	pdata = match->data;
895 
896 	indio_dev = devm_iio_device_alloc(dev, sizeof(*gpadc));
897 	if (!indio_dev)
898 		return -ENOMEM;
899 
900 	gpadc = iio_priv(indio_dev);
901 
902 	gpadc->twl6030_cal_tbl = devm_kzalloc(dev,
903 					sizeof(*gpadc->twl6030_cal_tbl) *
904 					pdata->nchannels, 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 reseting 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 		.owner	= THIS_MODULE,
999 		.pm	= &twl6030_gpadc_pm_ops,
1000 		.of_match_table = of_twl6030_match_tbl,
1001 	},
1002 };
1003 
1004 module_platform_driver(twl6030_gpadc_driver);
1005 
1006 MODULE_ALIAS("platform: " DRIVER_NAME);
1007 MODULE_AUTHOR("Balaji T K <balajitk@ti.com>");
1008 MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
1009 MODULE_AUTHOR("Oleksandr Kozaruk <oleksandr.kozaruk@ti.com");
1010 MODULE_DESCRIPTION("twl6030 ADC driver");
1011 MODULE_LICENSE("GPL");
1012