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/i2c/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 */
80struct 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 */
97struct twl6030_ideal_code {
98	int channel;
99	u16 code1;
100	u16 code2;
101	u16 volt1;
102	u16 volt2;
103};
104
105struct 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 */
117struct 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 */
135struct 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 */
151static 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
244static 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
354static inline int twl6030_gpadc_write(u8 reg, u8 val)
355{
356	return twl_i2c_write_u8(TWL6030_MODULE_GPADC, val, reg);
357}
358
359static inline int twl6030_gpadc_read(u8 reg, u8 *val)
360{
361
362	return twl_i2c_read(TWL6030_MODULE_GPADC, val, reg, 2);
363}
364
365static 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
378static 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
384static 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
393static int twl6030_start_conversion(int channel)
394{
395	return twl6030_gpadc_write(TWL6030_GPADC_CTRL_P1,
396					TWL6030_GPADC_CTRL_P1_SP1);
397}
398
399static 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
411static u8 twl6030_channel_to_reg(int channel)
412{
413	return TWL6030_GPADC_GPCH0_LSB + 2 * channel;
414}
415
416static 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
426static 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
438static 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
449static 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
464static 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
489static 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
517static 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	}
557err:
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 */
574static 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
608static 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
622static 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
695static 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
709static 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
810static 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
826static 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
844static const struct iio_info twl6030_gpadc_iio_info = {
845	.read_raw = &twl6030_gpadc_read_raw,
846	.driver_module = THIS_MODULE,
847};
848
849static const struct twl6030_gpadc_platform_data twl6030_pdata = {
850	.iio_channels = twl6030_gpadc_iio_channels,
851	.nchannels = TWL6030_GPADC_USED_CHANNELS,
852	.ideal = twl6030_ideal,
853	.start_conversion = twl6030_start_conversion,
854	.channel_to_reg = twl6030_channel_to_reg,
855	.calibrate = twl6030_calibration,
856};
857
858static const struct twl6030_gpadc_platform_data twl6032_pdata = {
859	.iio_channels = twl6032_gpadc_iio_channels,
860	.nchannels = TWL6032_GPADC_USED_CHANNELS,
861	.ideal = twl6032_ideal,
862	.start_conversion = twl6032_start_conversion,
863	.channel_to_reg = twl6032_channel_to_reg,
864	.calibrate = twl6032_calibration,
865};
866
867static const struct of_device_id of_twl6030_match_tbl[] = {
868	{
869		.compatible = "ti,twl6030-gpadc",
870		.data = &twl6030_pdata,
871	},
872	{
873		.compatible = "ti,twl6032-gpadc",
874		.data = &twl6032_pdata,
875	},
876	{ /* end */ }
877};
878
879static 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_kzalloc(dev,
902					sizeof(*gpadc->twl6030_cal_tbl) *
903					pdata->nchannels, GFP_KERNEL);
904	if (!gpadc->twl6030_cal_tbl)
905		return -ENOMEM;
906
907	gpadc->dev = dev;
908	gpadc->pdata = pdata;
909
910	platform_set_drvdata(pdev, indio_dev);
911	mutex_init(&gpadc->lock);
912	init_completion(&gpadc->irq_complete);
913
914	ret = pdata->calibrate(gpadc);
915	if (ret < 0) {
916		dev_err(&pdev->dev, "failed to read calibration registers\n");
917		return ret;
918	}
919
920	irq = platform_get_irq(pdev, 0);
921	if (irq < 0) {
922		dev_err(&pdev->dev, "failed to get irq\n");
923		return irq;
924	}
925
926	ret = devm_request_threaded_irq(dev, irq, NULL,
927				twl6030_gpadc_irq_handler,
928				IRQF_ONESHOT, "twl6030_gpadc", indio_dev);
929
930	ret = twl6030_gpadc_enable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK);
931	if (ret < 0) {
932		dev_err(&pdev->dev, "failed to enable GPADC interrupt\n");
933		return ret;
934	}
935
936	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS,
937					TWL6030_REG_TOGGLE1);
938	if (ret < 0) {
939		dev_err(&pdev->dev, "failed to enable GPADC module\n");
940		return ret;
941	}
942
943	indio_dev->name = DRIVER_NAME;
944	indio_dev->dev.parent = dev;
945	indio_dev->info = &twl6030_gpadc_iio_info;
946	indio_dev->modes = INDIO_DIRECT_MODE;
947	indio_dev->channels = pdata->iio_channels;
948	indio_dev->num_channels = pdata->nchannels;
949
950	return iio_device_register(indio_dev);
951}
952
953static int twl6030_gpadc_remove(struct platform_device *pdev)
954{
955	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
956
957	twl6030_gpadc_disable_irq(TWL6030_GPADC_RT_SW1_EOC_MASK);
958	iio_device_unregister(indio_dev);
959
960	return 0;
961}
962
963#ifdef CONFIG_PM_SLEEP
964static int twl6030_gpadc_suspend(struct device *pdev)
965{
966	int ret;
967
968	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCR,
969				TWL6030_REG_TOGGLE1);
970	if (ret)
971		dev_err(pdev, "error resetting GPADC (%d)!\n", ret);
972
973	return 0;
974};
975
976static int twl6030_gpadc_resume(struct device *pdev)
977{
978	int ret;
979
980	ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS,
981				TWL6030_REG_TOGGLE1);
982	if (ret)
983		dev_err(pdev, "error setting GPADC (%d)!\n", ret);
984
985	return 0;
986};
987#endif
988
989static SIMPLE_DEV_PM_OPS(twl6030_gpadc_pm_ops, twl6030_gpadc_suspend,
990					twl6030_gpadc_resume);
991
992static struct platform_driver twl6030_gpadc_driver = {
993	.probe		= twl6030_gpadc_probe,
994	.remove		= twl6030_gpadc_remove,
995	.driver		= {
996		.name	= DRIVER_NAME,
997		.pm	= &twl6030_gpadc_pm_ops,
998		.of_match_table = of_twl6030_match_tbl,
999	},
1000};
1001
1002module_platform_driver(twl6030_gpadc_driver);
1003
1004MODULE_ALIAS("platform:" DRIVER_NAME);
1005MODULE_AUTHOR("Balaji T K <balajitk@ti.com>");
1006MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
1007MODULE_AUTHOR("Oleksandr Kozaruk <oleksandr.kozaruk@ti.com");
1008MODULE_DESCRIPTION("twl6030 ADC driver");
1009MODULE_LICENSE("GPL");
1010