1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2017 Tony Lindgren <tony@atomide.com>
4 *
5 * Rewritten for Linux IIO framework with some code based on
6 * earlier driver found in the Motorola Linux kernel:
7 *
8 * Copyright (C) 2009-2010 Motorola, Inc.
9 */
10
11#include <linux/delay.h>
12#include <linux/device.h>
13#include <linux/err.h>
14#include <linux/init.h>
15#include <linux/interrupt.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/mod_devicetable.h>
19#include <linux/platform_device.h>
20#include <linux/property.h>
21#include <linux/regmap.h>
22
23#include <linux/iio/buffer.h>
24#include <linux/iio/driver.h>
25#include <linux/iio/iio.h>
26#include <linux/iio/kfifo_buf.h>
27#include <linux/mfd/motorola-cpcap.h>
28
29/* Register CPCAP_REG_ADCC1 bits */
30#define CPCAP_BIT_ADEN_AUTO_CLR		BIT(15)	/* Currently unused */
31#define CPCAP_BIT_CAL_MODE		BIT(14) /* Set with BIT_RAND0 */
32#define CPCAP_BIT_ADC_CLK_SEL1		BIT(13)	/* Currently unused */
33#define CPCAP_BIT_ADC_CLK_SEL0		BIT(12)	/* Currently unused */
34#define CPCAP_BIT_ATOX			BIT(11)
35#define CPCAP_BIT_ATO3			BIT(10)
36#define CPCAP_BIT_ATO2			BIT(9)
37#define CPCAP_BIT_ATO1			BIT(8)
38#define CPCAP_BIT_ATO0			BIT(7)
39#define CPCAP_BIT_ADA2			BIT(6)
40#define CPCAP_BIT_ADA1			BIT(5)
41#define CPCAP_BIT_ADA0			BIT(4)
42#define CPCAP_BIT_AD_SEL1		BIT(3)	/* Set for bank1 */
43#define CPCAP_BIT_RAND1			BIT(2)	/* Set for channel 16 & 17 */
44#define CPCAP_BIT_RAND0			BIT(1)	/* Set with CAL_MODE */
45#define CPCAP_BIT_ADEN			BIT(0)	/* Currently unused */
46
47#define CPCAP_REG_ADCC1_DEFAULTS	(CPCAP_BIT_ADEN_AUTO_CLR | \
48					 CPCAP_BIT_ADC_CLK_SEL0 |  \
49					 CPCAP_BIT_RAND1)
50
51/* Register CPCAP_REG_ADCC2 bits */
52#define CPCAP_BIT_CAL_FACTOR_ENABLE	BIT(15)	/* Currently unused */
53#define CPCAP_BIT_BATDETB_EN		BIT(14)	/* Currently unused */
54#define CPCAP_BIT_ADTRIG_ONESHOT	BIT(13)	/* Set for !TIMING_IMM */
55#define CPCAP_BIT_ASC			BIT(12)	/* Set for TIMING_IMM */
56#define CPCAP_BIT_ATOX_PS_FACTOR	BIT(11)
57#define CPCAP_BIT_ADC_PS_FACTOR1	BIT(10)
58#define CPCAP_BIT_ADC_PS_FACTOR0	BIT(9)
59#define CPCAP_BIT_AD4_SELECT		BIT(8)	/* Currently unused */
60#define CPCAP_BIT_ADC_BUSY		BIT(7)	/* Currently unused */
61#define CPCAP_BIT_THERMBIAS_EN		BIT(6)	/* Bias for AD0_BATTDETB */
62#define CPCAP_BIT_ADTRIG_DIS		BIT(5)	/* Disable interrupt */
63#define CPCAP_BIT_LIADC			BIT(4)	/* Currently unused */
64#define CPCAP_BIT_TS_REFEN		BIT(3)	/* Currently unused */
65#define CPCAP_BIT_TS_M2			BIT(2)	/* Currently unused */
66#define CPCAP_BIT_TS_M1			BIT(1)	/* Currently unused */
67#define CPCAP_BIT_TS_M0			BIT(0)	/* Currently unused */
68
69#define CPCAP_REG_ADCC2_DEFAULTS	(CPCAP_BIT_AD4_SELECT | \
70					 CPCAP_BIT_ADTRIG_DIS | \
71					 CPCAP_BIT_LIADC | \
72					 CPCAP_BIT_TS_M2 | \
73					 CPCAP_BIT_TS_M1)
74
75#define CPCAP_MAX_TEMP_LVL		27
76#define CPCAP_FOUR_POINT_TWO_ADC	801
77#define ST_ADC_CAL_CHRGI_HIGH_THRESHOLD	530
78#define ST_ADC_CAL_CHRGI_LOW_THRESHOLD	494
79#define ST_ADC_CAL_BATTI_HIGH_THRESHOLD	530
80#define ST_ADC_CAL_BATTI_LOW_THRESHOLD	494
81#define ST_ADC_CALIBRATE_DIFF_THRESHOLD	3
82
83#define CPCAP_ADC_MAX_RETRIES		5	/* Calibration */
84
85/*
86 * struct cpcap_adc_ato - timing settings for cpcap adc
87 *
88 * Unfortunately no cpcap documentation available, please document when
89 * using these.
90 */
91struct cpcap_adc_ato {
92	unsigned short ato_in;
93	unsigned short atox_in;
94	unsigned short adc_ps_factor_in;
95	unsigned short atox_ps_factor_in;
96	unsigned short ato_out;
97	unsigned short atox_out;
98	unsigned short adc_ps_factor_out;
99	unsigned short atox_ps_factor_out;
100};
101
102/**
103 * struct cpcap-adc - cpcap adc device driver data
104 * @reg: cpcap regmap
105 * @dev: struct device
106 * @vendor: cpcap vendor
107 * @irq: interrupt
108 * @lock: mutex
109 * @ato: request timings
110 * @wq_data_avail: work queue
111 * @done: work done
112 */
113struct cpcap_adc {
114	struct regmap *reg;
115	struct device *dev;
116	u16 vendor;
117	int irq;
118	struct mutex lock;	/* ADC register access lock */
119	const struct cpcap_adc_ato *ato;
120	wait_queue_head_t wq_data_avail;
121	bool done;
122};
123
124/*
125 * enum cpcap_adc_channel - cpcap adc channels
126 */
127enum cpcap_adc_channel {
128	/* Bank0 channels */
129	CPCAP_ADC_AD0,		/* Battery temperature */
130	CPCAP_ADC_BATTP,	/* Battery voltage */
131	CPCAP_ADC_VBUS,		/* USB VBUS voltage */
132	CPCAP_ADC_AD3,		/* Die temperature when charging */
133	CPCAP_ADC_BPLUS_AD4,	/* Another battery or system voltage */
134	CPCAP_ADC_CHG_ISENSE,	/* Calibrated charge current */
135	CPCAP_ADC_BATTI,	/* Calibrated system current */
136	CPCAP_ADC_USB_ID,	/* USB OTG ID, unused on droid 4? */
137
138	/* Bank1 channels */
139	CPCAP_ADC_AD8,		/* Seems unused */
140	CPCAP_ADC_AD9,		/* Seems unused */
141	CPCAP_ADC_LICELL,	/* Maybe system voltage? Always 3V */
142	CPCAP_ADC_HV_BATTP,	/* Another battery detection? */
143	CPCAP_ADC_TSX1_AD12,	/* Seems unused, for touchscreen? */
144	CPCAP_ADC_TSX2_AD13,	/* Seems unused, for touchscreen? */
145	CPCAP_ADC_TSY1_AD14,	/* Seems unused, for touchscreen? */
146	CPCAP_ADC_TSY2_AD15,	/* Seems unused, for touchscreen? */
147
148	/* Remuxed channels using bank0 entries */
149	CPCAP_ADC_BATTP_PI16,	/* Alternative mux mode for BATTP */
150	CPCAP_ADC_BATTI_PI17,	/* Alternative mux mode for BATTI */
151
152	CPCAP_ADC_CHANNEL_NUM,
153};
154
155/*
156 * enum cpcap_adc_timing - cpcap adc timing options
157 *
158 * CPCAP_ADC_TIMING_IMM seems to be immediate with no timings.
159 * Please document when using.
160 */
161enum cpcap_adc_timing {
162	CPCAP_ADC_TIMING_IMM,
163	CPCAP_ADC_TIMING_IN,
164	CPCAP_ADC_TIMING_OUT,
165};
166
167/**
168 * struct cpcap_adc_phasing_tbl - cpcap phasing table
169 * @offset: offset in the phasing table
170 * @multiplier: multiplier in the phasing table
171 * @divider: divider in the phasing table
172 * @min: minimum value
173 * @max: maximum value
174 */
175struct cpcap_adc_phasing_tbl {
176	short offset;
177	unsigned short multiplier;
178	unsigned short divider;
179	short min;
180	short max;
181};
182
183/**
184 * struct cpcap_adc_conversion_tbl - cpcap conversion table
185 * @conv_type: conversion type
186 * @align_offset: align offset
187 * @conv_offset: conversion offset
188 * @cal_offset: calibration offset
189 * @multiplier: conversion multiplier
190 * @divider: conversion divider
191 */
192struct cpcap_adc_conversion_tbl {
193	enum iio_chan_info_enum conv_type;
194	int align_offset;
195	int conv_offset;
196	int cal_offset;
197	int multiplier;
198	int divider;
199};
200
201/**
202 * struct cpcap_adc_request - cpcap adc request
203 * @channel: request channel
204 * @phase_tbl: channel phasing table
205 * @conv_tbl: channel conversion table
206 * @bank_index: channel index within the bank
207 * @timing: timing settings
208 * @result: result
209 */
210struct cpcap_adc_request {
211	int channel;
212	const struct cpcap_adc_phasing_tbl *phase_tbl;
213	const struct cpcap_adc_conversion_tbl *conv_tbl;
214	int bank_index;
215	enum cpcap_adc_timing timing;
216	int result;
217};
218
219/* Phasing table for channels. Note that channels 16 & 17 use BATTP and BATTI */
220static const struct cpcap_adc_phasing_tbl bank_phasing[] = {
221	/* Bank0 */
222	[CPCAP_ADC_AD0] =          {0, 0x80, 0x80,    0, 1023},
223	[CPCAP_ADC_BATTP] =        {0, 0x80, 0x80,    0, 1023},
224	[CPCAP_ADC_VBUS] =         {0, 0x80, 0x80,    0, 1023},
225	[CPCAP_ADC_AD3] =          {0, 0x80, 0x80,    0, 1023},
226	[CPCAP_ADC_BPLUS_AD4] =    {0, 0x80, 0x80,    0, 1023},
227	[CPCAP_ADC_CHG_ISENSE] =   {0, 0x80, 0x80, -512,  511},
228	[CPCAP_ADC_BATTI] =        {0, 0x80, 0x80, -512,  511},
229	[CPCAP_ADC_USB_ID] =       {0, 0x80, 0x80,    0, 1023},
230
231	/* Bank1 */
232	[CPCAP_ADC_AD8] =          {0, 0x80, 0x80,    0, 1023},
233	[CPCAP_ADC_AD9] =          {0, 0x80, 0x80,    0, 1023},
234	[CPCAP_ADC_LICELL] =       {0, 0x80, 0x80,    0, 1023},
235	[CPCAP_ADC_HV_BATTP] =     {0, 0x80, 0x80,    0, 1023},
236	[CPCAP_ADC_TSX1_AD12] =    {0, 0x80, 0x80,    0, 1023},
237	[CPCAP_ADC_TSX2_AD13] =    {0, 0x80, 0x80,    0, 1023},
238	[CPCAP_ADC_TSY1_AD14] =    {0, 0x80, 0x80,    0, 1023},
239	[CPCAP_ADC_TSY2_AD15] =    {0, 0x80, 0x80,    0, 1023},
240};
241
242/*
243 * Conversion table for channels. Updated during init based on calibration.
244 * Here too channels 16 & 17 use BATTP and BATTI.
245 */
246static struct cpcap_adc_conversion_tbl bank_conversion[] = {
247	/* Bank0 */
248	[CPCAP_ADC_AD0] = {
249		IIO_CHAN_INFO_PROCESSED,    0,    0, 0,     1,    1,
250	},
251	[CPCAP_ADC_BATTP] = {
252		IIO_CHAN_INFO_PROCESSED,    0, 2400, 0,  2300, 1023,
253	},
254	[CPCAP_ADC_VBUS] = {
255		IIO_CHAN_INFO_PROCESSED,    0,    0, 0, 10000, 1023,
256	},
257	[CPCAP_ADC_AD3] = {
258		IIO_CHAN_INFO_PROCESSED,    0,    0, 0,     1,    1,
259		},
260	[CPCAP_ADC_BPLUS_AD4] = {
261		IIO_CHAN_INFO_PROCESSED,    0, 2400, 0,  2300, 1023,
262	},
263	[CPCAP_ADC_CHG_ISENSE] = {
264		IIO_CHAN_INFO_PROCESSED, -512,    2, 0,  5000, 1023,
265	},
266	[CPCAP_ADC_BATTI] = {
267		IIO_CHAN_INFO_PROCESSED, -512,    2, 0,  5000, 1023,
268	},
269	[CPCAP_ADC_USB_ID] = {
270		IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
271	},
272
273	/* Bank1 */
274	[CPCAP_ADC_AD8] = {
275		IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
276	},
277	[CPCAP_ADC_AD9] = {
278		IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
279	},
280	[CPCAP_ADC_LICELL] = {
281		IIO_CHAN_INFO_PROCESSED,    0,    0, 0,  3400, 1023,
282	},
283	[CPCAP_ADC_HV_BATTP] = {
284		IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
285	},
286	[CPCAP_ADC_TSX1_AD12] = {
287		IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
288	},
289	[CPCAP_ADC_TSX2_AD13] = {
290		IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
291	},
292	[CPCAP_ADC_TSY1_AD14] = {
293		IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
294	},
295	[CPCAP_ADC_TSY2_AD15] = {
296		IIO_CHAN_INFO_RAW,          0,    0, 0,     1,    1,
297	},
298};
299
300/*
301 * Temperature lookup table of register values to milliCelcius.
302 * REVISIT: Check the duplicate 0x3ff entry in a freezer
303 */
304static const int temp_map[CPCAP_MAX_TEMP_LVL][2] = {
305	{ 0x03ff, -40000 },
306	{ 0x03ff, -35000 },
307	{ 0x03ef, -30000 },
308	{ 0x03b2, -25000 },
309	{ 0x036c, -20000 },
310	{ 0x0320, -15000 },
311	{ 0x02d0, -10000 },
312	{ 0x027f, -5000 },
313	{ 0x022f, 0 },
314	{ 0x01e4, 5000 },
315	{ 0x019f, 10000 },
316	{ 0x0161, 15000 },
317	{ 0x012b, 20000 },
318	{ 0x00fc, 25000 },
319	{ 0x00d4, 30000 },
320	{ 0x00b2, 35000 },
321	{ 0x0095, 40000 },
322	{ 0x007d, 45000 },
323	{ 0x0069, 50000 },
324	{ 0x0059, 55000 },
325	{ 0x004b, 60000 },
326	{ 0x003f, 65000 },
327	{ 0x0036, 70000 },
328	{ 0x002e, 75000 },
329	{ 0x0027, 80000 },
330	{ 0x0022, 85000 },
331	{ 0x001d, 90000 },
332};
333
334#define CPCAP_CHAN(_type, _index, _address, _datasheet_name) {	\
335	.type = (_type), \
336	.address = (_address), \
337	.indexed = 1, \
338	.channel = (_index), \
339	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
340			      BIT(IIO_CHAN_INFO_PROCESSED), \
341	.scan_index = (_index), \
342	.scan_type = { \
343		.sign = 'u', \
344		.realbits = 10, \
345		.storagebits = 16, \
346		.endianness = IIO_CPU, \
347	}, \
348	.datasheet_name = (_datasheet_name), \
349}
350
351/*
352 * The datasheet names are from Motorola mapphone Linux kernel except
353 * for the last two which might be uncalibrated charge voltage and
354 * current.
355 */
356static const struct iio_chan_spec cpcap_adc_channels[] = {
357	/* Bank0 */
358	CPCAP_CHAN(IIO_TEMP,    0, CPCAP_REG_ADCD0,  "battdetb"),
359	CPCAP_CHAN(IIO_VOLTAGE, 1, CPCAP_REG_ADCD1,  "battp"),
360	CPCAP_CHAN(IIO_VOLTAGE, 2, CPCAP_REG_ADCD2,  "vbus"),
361	CPCAP_CHAN(IIO_TEMP,    3, CPCAP_REG_ADCD3,  "ad3"),
362	CPCAP_CHAN(IIO_VOLTAGE, 4, CPCAP_REG_ADCD4,  "ad4"),
363	CPCAP_CHAN(IIO_CURRENT, 5, CPCAP_REG_ADCD5,  "chg_isense"),
364	CPCAP_CHAN(IIO_CURRENT, 6, CPCAP_REG_ADCD6,  "batti"),
365	CPCAP_CHAN(IIO_VOLTAGE, 7, CPCAP_REG_ADCD7,  "usb_id"),
366
367	/* Bank1 */
368	CPCAP_CHAN(IIO_CURRENT, 8, CPCAP_REG_ADCD0,  "ad8"),
369	CPCAP_CHAN(IIO_VOLTAGE, 9, CPCAP_REG_ADCD1,  "ad9"),
370	CPCAP_CHAN(IIO_VOLTAGE, 10, CPCAP_REG_ADCD2, "licell"),
371	CPCAP_CHAN(IIO_VOLTAGE, 11, CPCAP_REG_ADCD3, "hv_battp"),
372	CPCAP_CHAN(IIO_VOLTAGE, 12, CPCAP_REG_ADCD4, "tsx1_ad12"),
373	CPCAP_CHAN(IIO_VOLTAGE, 13, CPCAP_REG_ADCD5, "tsx2_ad13"),
374	CPCAP_CHAN(IIO_VOLTAGE, 14, CPCAP_REG_ADCD6, "tsy1_ad14"),
375	CPCAP_CHAN(IIO_VOLTAGE, 15, CPCAP_REG_ADCD7, "tsy2_ad15"),
376
377	/* There are two registers with multiplexed functionality */
378	CPCAP_CHAN(IIO_VOLTAGE, 16, CPCAP_REG_ADCD0, "chg_vsense"),
379	CPCAP_CHAN(IIO_CURRENT, 17, CPCAP_REG_ADCD1, "batti2"),
380};
381
382static irqreturn_t cpcap_adc_irq_thread(int irq, void *data)
383{
384	struct iio_dev *indio_dev = data;
385	struct cpcap_adc *ddata = iio_priv(indio_dev);
386	int error;
387
388	error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
389				   CPCAP_BIT_ADTRIG_DIS,
390				   CPCAP_BIT_ADTRIG_DIS);
391	if (error)
392		return IRQ_NONE;
393
394	ddata->done = true;
395	wake_up_interruptible(&ddata->wq_data_avail);
396
397	return IRQ_HANDLED;
398}
399
400/* ADC calibration functions */
401static void cpcap_adc_setup_calibrate(struct cpcap_adc *ddata,
402				      enum cpcap_adc_channel chan)
403{
404	unsigned int value = 0;
405	unsigned long timeout = jiffies + msecs_to_jiffies(3000);
406	int error;
407
408	if ((chan != CPCAP_ADC_CHG_ISENSE) &&
409	    (chan != CPCAP_ADC_BATTI))
410		return;
411
412	value |= CPCAP_BIT_CAL_MODE | CPCAP_BIT_RAND0;
413	value |= ((chan << 4) &
414		  (CPCAP_BIT_ADA2 | CPCAP_BIT_ADA1 | CPCAP_BIT_ADA0));
415
416	error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC1,
417				   CPCAP_BIT_CAL_MODE | CPCAP_BIT_ATOX |
418				   CPCAP_BIT_ATO3 | CPCAP_BIT_ATO2 |
419				   CPCAP_BIT_ATO1 | CPCAP_BIT_ATO0 |
420				   CPCAP_BIT_ADA2 | CPCAP_BIT_ADA1 |
421				   CPCAP_BIT_ADA0 | CPCAP_BIT_AD_SEL1 |
422				   CPCAP_BIT_RAND1 | CPCAP_BIT_RAND0,
423				   value);
424	if (error)
425		return;
426
427	error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
428				   CPCAP_BIT_ATOX_PS_FACTOR |
429				   CPCAP_BIT_ADC_PS_FACTOR1 |
430				   CPCAP_BIT_ADC_PS_FACTOR0,
431				   0);
432	if (error)
433		return;
434
435	error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
436				   CPCAP_BIT_ADTRIG_DIS,
437				   CPCAP_BIT_ADTRIG_DIS);
438	if (error)
439		return;
440
441	error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
442				   CPCAP_BIT_ASC,
443				   CPCAP_BIT_ASC);
444	if (error)
445		return;
446
447	do {
448		schedule_timeout_uninterruptible(1);
449		error = regmap_read(ddata->reg, CPCAP_REG_ADCC2, &value);
450		if (error)
451			return;
452	} while ((value & CPCAP_BIT_ASC) && time_before(jiffies, timeout));
453
454	if (value & CPCAP_BIT_ASC)
455		dev_err(ddata->dev,
456			"Timeout waiting for calibration to complete\n");
457
458	error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC1,
459				   CPCAP_BIT_CAL_MODE, 0);
460	if (error)
461		return;
462}
463
464static int cpcap_adc_calibrate_one(struct cpcap_adc *ddata,
465				   int channel,
466				   u16 calibration_register,
467				   int lower_threshold,
468				   int upper_threshold)
469{
470	unsigned int calibration_data[2];
471	unsigned short cal_data_diff;
472	int i, error;
473
474	for (i = 0; i < CPCAP_ADC_MAX_RETRIES; i++) {
475		calibration_data[0]  = 0;
476		calibration_data[1]  = 0;
477		cal_data_diff = 0;
478		cpcap_adc_setup_calibrate(ddata, channel);
479		error = regmap_read(ddata->reg, calibration_register,
480				    &calibration_data[0]);
481		if (error)
482			return error;
483		cpcap_adc_setup_calibrate(ddata, channel);
484		error = regmap_read(ddata->reg, calibration_register,
485				    &calibration_data[1]);
486		if (error)
487			return error;
488
489		if (calibration_data[0] > calibration_data[1])
490			cal_data_diff =
491				calibration_data[0] - calibration_data[1];
492		else
493			cal_data_diff =
494				calibration_data[1] - calibration_data[0];
495
496		if (((calibration_data[1] >= lower_threshold) &&
497		     (calibration_data[1] <= upper_threshold) &&
498		     (cal_data_diff <= ST_ADC_CALIBRATE_DIFF_THRESHOLD)) ||
499		    (ddata->vendor == CPCAP_VENDOR_TI)) {
500			bank_conversion[channel].cal_offset =
501				((short)calibration_data[1] * -1) + 512;
502			dev_dbg(ddata->dev, "ch%i calibration complete: %i\n",
503				channel, bank_conversion[channel].cal_offset);
504			break;
505		}
506		usleep_range(5000, 10000);
507	}
508
509	return 0;
510}
511
512static int cpcap_adc_calibrate(struct cpcap_adc *ddata)
513{
514	int error;
515
516	error = cpcap_adc_calibrate_one(ddata, CPCAP_ADC_CHG_ISENSE,
517					CPCAP_REG_ADCAL1,
518					ST_ADC_CAL_CHRGI_LOW_THRESHOLD,
519					ST_ADC_CAL_CHRGI_HIGH_THRESHOLD);
520	if (error)
521		return error;
522
523	error = cpcap_adc_calibrate_one(ddata, CPCAP_ADC_BATTI,
524					CPCAP_REG_ADCAL2,
525					ST_ADC_CAL_BATTI_LOW_THRESHOLD,
526					ST_ADC_CAL_BATTI_HIGH_THRESHOLD);
527	if (error)
528		return error;
529
530	return 0;
531}
532
533/* ADC setup, read and scale functions */
534static void cpcap_adc_setup_bank(struct cpcap_adc *ddata,
535				 struct cpcap_adc_request *req)
536{
537	const struct cpcap_adc_ato *ato = ddata->ato;
538	unsigned short value1 = 0;
539	unsigned short value2 = 0;
540	int error;
541
542	if (!ato)
543		return;
544
545	switch (req->channel) {
546	case CPCAP_ADC_AD0:
547		value2 |= CPCAP_BIT_THERMBIAS_EN;
548		error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
549					   CPCAP_BIT_THERMBIAS_EN,
550					   value2);
551		if (error)
552			return;
553		usleep_range(800, 1000);
554		break;
555	case CPCAP_ADC_AD8 ... CPCAP_ADC_TSY2_AD15:
556		value1 |= CPCAP_BIT_AD_SEL1;
557		break;
558	case CPCAP_ADC_BATTP_PI16 ... CPCAP_ADC_BATTI_PI17:
559		value1 |= CPCAP_BIT_RAND1;
560	default:
561		break;
562	}
563
564	switch (req->timing) {
565	case CPCAP_ADC_TIMING_IN:
566		value1 |= ato->ato_in;
567		value1 |= ato->atox_in;
568		value2 |= ato->adc_ps_factor_in;
569		value2 |= ato->atox_ps_factor_in;
570		break;
571	case CPCAP_ADC_TIMING_OUT:
572		value1 |= ato->ato_out;
573		value1 |= ato->atox_out;
574		value2 |= ato->adc_ps_factor_out;
575		value2 |= ato->atox_ps_factor_out;
576		break;
577
578	case CPCAP_ADC_TIMING_IMM:
579	default:
580		break;
581	}
582
583	error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC1,
584				   CPCAP_BIT_CAL_MODE | CPCAP_BIT_ATOX |
585				   CPCAP_BIT_ATO3 | CPCAP_BIT_ATO2 |
586				   CPCAP_BIT_ATO1 | CPCAP_BIT_ATO0 |
587				   CPCAP_BIT_ADA2 | CPCAP_BIT_ADA1 |
588				   CPCAP_BIT_ADA0 | CPCAP_BIT_AD_SEL1 |
589				   CPCAP_BIT_RAND1 | CPCAP_BIT_RAND0,
590				   value1);
591	if (error)
592		return;
593
594	error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
595				   CPCAP_BIT_ATOX_PS_FACTOR |
596				   CPCAP_BIT_ADC_PS_FACTOR1 |
597				   CPCAP_BIT_ADC_PS_FACTOR0 |
598				   CPCAP_BIT_THERMBIAS_EN,
599				   value2);
600	if (error)
601		return;
602
603	if (req->timing == CPCAP_ADC_TIMING_IMM) {
604		error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
605					   CPCAP_BIT_ADTRIG_DIS,
606					   CPCAP_BIT_ADTRIG_DIS);
607		if (error)
608			return;
609
610		error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
611					   CPCAP_BIT_ASC,
612					   CPCAP_BIT_ASC);
613		if (error)
614			return;
615	} else {
616		error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
617					   CPCAP_BIT_ADTRIG_ONESHOT,
618					   CPCAP_BIT_ADTRIG_ONESHOT);
619		if (error)
620			return;
621
622		error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
623					   CPCAP_BIT_ADTRIG_DIS, 0);
624		if (error)
625			return;
626	}
627}
628
629static int cpcap_adc_start_bank(struct cpcap_adc *ddata,
630				struct cpcap_adc_request *req)
631{
632	int i, error;
633
634	req->timing = CPCAP_ADC_TIMING_IMM;
635	ddata->done = false;
636
637	for (i = 0; i < CPCAP_ADC_MAX_RETRIES; i++) {
638		cpcap_adc_setup_bank(ddata, req);
639		error = wait_event_interruptible_timeout(ddata->wq_data_avail,
640							 ddata->done,
641							 msecs_to_jiffies(50));
642		if (error > 0)
643			return 0;
644
645		if (error == 0) {
646			error = -ETIMEDOUT;
647			continue;
648		}
649
650		if (error < 0)
651			return error;
652	}
653
654	return error;
655}
656
657static int cpcap_adc_stop_bank(struct cpcap_adc *ddata)
658{
659	int error;
660
661	error = regmap_update_bits(ddata->reg, CPCAP_REG_ADCC1,
662				   0xffff,
663				   CPCAP_REG_ADCC1_DEFAULTS);
664	if (error)
665		return error;
666
667	return regmap_update_bits(ddata->reg, CPCAP_REG_ADCC2,
668				  0xffff,
669				  CPCAP_REG_ADCC2_DEFAULTS);
670}
671
672static void cpcap_adc_phase(struct cpcap_adc_request *req)
673{
674	const struct cpcap_adc_conversion_tbl *conv_tbl = req->conv_tbl;
675	const struct cpcap_adc_phasing_tbl *phase_tbl = req->phase_tbl;
676	int index = req->channel;
677
678	/* Remuxed channels 16 and 17 use BATTP and BATTI entries */
679	switch (req->channel) {
680	case CPCAP_ADC_BATTP:
681	case CPCAP_ADC_BATTP_PI16:
682		index = req->bank_index;
683		req->result -= phase_tbl[index].offset;
684		req->result -= CPCAP_FOUR_POINT_TWO_ADC;
685		req->result *= phase_tbl[index].multiplier;
686		if (phase_tbl[index].divider == 0)
687			return;
688		req->result /= phase_tbl[index].divider;
689		req->result += CPCAP_FOUR_POINT_TWO_ADC;
690		break;
691	case CPCAP_ADC_BATTI_PI17:
692		index = req->bank_index;
693		fallthrough;
694	default:
695		req->result += conv_tbl[index].cal_offset;
696		req->result += conv_tbl[index].align_offset;
697		req->result *= phase_tbl[index].multiplier;
698		if (phase_tbl[index].divider == 0)
699			return;
700		req->result /= phase_tbl[index].divider;
701		req->result += phase_tbl[index].offset;
702		break;
703	}
704
705	if (req->result < phase_tbl[index].min)
706		req->result = phase_tbl[index].min;
707	else if (req->result > phase_tbl[index].max)
708		req->result = phase_tbl[index].max;
709}
710
711/* Looks up temperatures in a table and calculates averages if needed */
712static int cpcap_adc_table_to_millicelcius(unsigned short value)
713{
714	int i, result = 0, alpha;
715
716	if (value <= temp_map[CPCAP_MAX_TEMP_LVL - 1][0])
717		return temp_map[CPCAP_MAX_TEMP_LVL - 1][1];
718
719	if (value >= temp_map[0][0])
720		return temp_map[0][1];
721
722	for (i = 0; i < CPCAP_MAX_TEMP_LVL - 1; i++) {
723		if ((value <= temp_map[i][0]) &&
724		    (value >= temp_map[i + 1][0])) {
725			if (value == temp_map[i][0]) {
726				result = temp_map[i][1];
727			} else if (value == temp_map[i + 1][0]) {
728				result = temp_map[i + 1][1];
729			} else {
730				alpha = ((value - temp_map[i][0]) * 1000) /
731					(temp_map[i + 1][0] - temp_map[i][0]);
732
733				result = temp_map[i][1] +
734					((alpha * (temp_map[i + 1][1] -
735						 temp_map[i][1])) / 1000);
736			}
737			break;
738		}
739	}
740
741	return result;
742}
743
744static void cpcap_adc_convert(struct cpcap_adc_request *req)
745{
746	const struct cpcap_adc_conversion_tbl *conv_tbl = req->conv_tbl;
747	int index = req->channel;
748
749	/* Remuxed channels 16 and 17 use BATTP and BATTI entries */
750	switch (req->channel) {
751	case CPCAP_ADC_BATTP_PI16:
752		index = CPCAP_ADC_BATTP;
753		break;
754	case CPCAP_ADC_BATTI_PI17:
755		index = CPCAP_ADC_BATTI;
756		break;
757	default:
758		break;
759	}
760
761	/* No conversion for raw channels */
762	if (conv_tbl[index].conv_type == IIO_CHAN_INFO_RAW)
763		return;
764
765	/* Temperatures use a lookup table instead of conversion table */
766	if ((req->channel == CPCAP_ADC_AD0) ||
767	    (req->channel == CPCAP_ADC_AD3)) {
768		req->result =
769			cpcap_adc_table_to_millicelcius(req->result);
770
771		return;
772	}
773
774	/* All processed channels use a conversion table */
775	req->result *= conv_tbl[index].multiplier;
776	if (conv_tbl[index].divider == 0)
777		return;
778	req->result /= conv_tbl[index].divider;
779	req->result += conv_tbl[index].conv_offset;
780}
781
782/*
783 * REVISIT: Check if timed sampling can use multiple channels at the
784 * same time. If not, replace channel_mask with just channel.
785 */
786static int cpcap_adc_read_bank_scaled(struct cpcap_adc *ddata,
787				      struct cpcap_adc_request *req)
788{
789	int calibration_data, error, addr;
790
791	if (ddata->vendor == CPCAP_VENDOR_TI) {
792		error = regmap_read(ddata->reg, CPCAP_REG_ADCAL1,
793				    &calibration_data);
794		if (error)
795			return error;
796		bank_conversion[CPCAP_ADC_CHG_ISENSE].cal_offset =
797			((short)calibration_data * -1) + 512;
798
799		error = regmap_read(ddata->reg, CPCAP_REG_ADCAL2,
800				    &calibration_data);
801		if (error)
802			return error;
803		bank_conversion[CPCAP_ADC_BATTI].cal_offset =
804			((short)calibration_data * -1) + 512;
805	}
806
807	addr = CPCAP_REG_ADCD0 + req->bank_index * 4;
808
809	error = regmap_read(ddata->reg, addr, &req->result);
810	if (error)
811		return error;
812
813	req->result &= 0x3ff;
814	cpcap_adc_phase(req);
815	cpcap_adc_convert(req);
816
817	return 0;
818}
819
820static int cpcap_adc_init_request(struct cpcap_adc_request *req,
821				  int channel)
822{
823	req->channel = channel;
824	req->phase_tbl = bank_phasing;
825	req->conv_tbl = bank_conversion;
826
827	switch (channel) {
828	case CPCAP_ADC_AD0 ... CPCAP_ADC_USB_ID:
829		req->bank_index = channel;
830		break;
831	case CPCAP_ADC_AD8 ... CPCAP_ADC_TSY2_AD15:
832		req->bank_index = channel - 8;
833		break;
834	case CPCAP_ADC_BATTP_PI16:
835		req->bank_index = CPCAP_ADC_BATTP;
836		break;
837	case CPCAP_ADC_BATTI_PI17:
838		req->bank_index = CPCAP_ADC_BATTI;
839		break;
840	default:
841		return -EINVAL;
842	}
843
844	return 0;
845}
846
847static int cpcap_adc_read_st_die_temp(struct cpcap_adc *ddata,
848				      int addr, int *val)
849{
850	int error;
851
852	error = regmap_read(ddata->reg, addr, val);
853	if (error)
854		return error;
855
856	*val -= 282;
857	*val *= 114;
858	*val += 25000;
859
860	return 0;
861}
862
863static int cpcap_adc_read(struct iio_dev *indio_dev,
864			  struct iio_chan_spec const *chan,
865			  int *val, int *val2, long mask)
866{
867	struct cpcap_adc *ddata = iio_priv(indio_dev);
868	struct cpcap_adc_request req;
869	int error;
870
871	error = cpcap_adc_init_request(&req, chan->channel);
872	if (error)
873		return error;
874
875	switch (mask) {
876	case IIO_CHAN_INFO_RAW:
877		mutex_lock(&ddata->lock);
878		error = cpcap_adc_start_bank(ddata, &req);
879		if (error)
880			goto err_unlock;
881		error = regmap_read(ddata->reg, chan->address, val);
882		if (error)
883			goto err_unlock;
884		error = cpcap_adc_stop_bank(ddata);
885		if (error)
886			goto err_unlock;
887		mutex_unlock(&ddata->lock);
888		break;
889	case IIO_CHAN_INFO_PROCESSED:
890		mutex_lock(&ddata->lock);
891		error = cpcap_adc_start_bank(ddata, &req);
892		if (error)
893			goto err_unlock;
894		if ((ddata->vendor == CPCAP_VENDOR_ST) &&
895		    (chan->channel == CPCAP_ADC_AD3)) {
896			error = cpcap_adc_read_st_die_temp(ddata,
897							   chan->address,
898							   &req.result);
899			if (error)
900				goto err_unlock;
901		} else {
902			error = cpcap_adc_read_bank_scaled(ddata, &req);
903			if (error)
904				goto err_unlock;
905		}
906		error = cpcap_adc_stop_bank(ddata);
907		if (error)
908			goto err_unlock;
909		mutex_unlock(&ddata->lock);
910		*val = req.result;
911		break;
912	default:
913		return -EINVAL;
914	}
915
916	return IIO_VAL_INT;
917
918err_unlock:
919	mutex_unlock(&ddata->lock);
920	dev_err(ddata->dev, "error reading ADC: %i\n", error);
921
922	return error;
923}
924
925static const struct iio_info cpcap_adc_info = {
926	.read_raw = &cpcap_adc_read,
927};
928
929/*
930 * Configuration for Motorola mapphone series such as droid 4.
931 * Copied from the Motorola mapphone kernel tree.
932 */
933static const struct cpcap_adc_ato mapphone_adc = {
934	.ato_in = 0x0480,
935	.atox_in = 0,
936	.adc_ps_factor_in = 0x0200,
937	.atox_ps_factor_in = 0,
938	.ato_out = 0,
939	.atox_out = 0,
940	.adc_ps_factor_out = 0,
941	.atox_ps_factor_out = 0,
942};
943
944static const struct of_device_id cpcap_adc_id_table[] = {
945	{
946		.compatible = "motorola,cpcap-adc",
947	},
948	{
949		.compatible = "motorola,mapphone-cpcap-adc",
950		.data = &mapphone_adc,
951	},
952	{ /* sentinel */ },
953};
954MODULE_DEVICE_TABLE(of, cpcap_adc_id_table);
955
956static int cpcap_adc_probe(struct platform_device *pdev)
957{
958	struct cpcap_adc *ddata;
959	struct iio_dev *indio_dev;
960	int error;
961
962	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*ddata));
963	if (!indio_dev) {
964		dev_err(&pdev->dev, "failed to allocate iio device\n");
965
966		return -ENOMEM;
967	}
968	ddata = iio_priv(indio_dev);
969	ddata->ato = device_get_match_data(&pdev->dev);
970	if (!ddata->ato)
971		return -ENODEV;
972	ddata->dev = &pdev->dev;
973
974	mutex_init(&ddata->lock);
975	init_waitqueue_head(&ddata->wq_data_avail);
976
977	indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
978	indio_dev->channels = cpcap_adc_channels;
979	indio_dev->num_channels = ARRAY_SIZE(cpcap_adc_channels);
980	indio_dev->name = dev_name(&pdev->dev);
981	indio_dev->info = &cpcap_adc_info;
982
983	ddata->reg = dev_get_regmap(pdev->dev.parent, NULL);
984	if (!ddata->reg)
985		return -ENODEV;
986
987	error = cpcap_get_vendor(ddata->dev, ddata->reg, &ddata->vendor);
988	if (error)
989		return error;
990
991	platform_set_drvdata(pdev, indio_dev);
992
993	ddata->irq = platform_get_irq_byname(pdev, "adcdone");
994	if (ddata->irq < 0)
995		return -ENODEV;
996
997	error = devm_request_threaded_irq(&pdev->dev, ddata->irq, NULL,
998					  cpcap_adc_irq_thread,
999					  IRQF_TRIGGER_NONE | IRQF_ONESHOT,
1000					  "cpcap-adc", indio_dev);
1001	if (error) {
1002		dev_err(&pdev->dev, "could not get irq: %i\n",
1003			error);
1004
1005		return error;
1006	}
1007
1008	error = cpcap_adc_calibrate(ddata);
1009	if (error)
1010		return error;
1011
1012	dev_info(&pdev->dev, "CPCAP ADC device probed\n");
1013
1014	return devm_iio_device_register(&pdev->dev, indio_dev);
1015}
1016
1017static struct platform_driver cpcap_adc_driver = {
1018	.driver = {
1019		.name = "cpcap_adc",
1020		.of_match_table = cpcap_adc_id_table,
1021	},
1022	.probe = cpcap_adc_probe,
1023};
1024
1025module_platform_driver(cpcap_adc_driver);
1026
1027MODULE_ALIAS("platform:cpcap_adc");
1028MODULE_DESCRIPTION("CPCAP ADC driver");
1029MODULE_AUTHOR("Tony Lindgren <tony@atomide.com");
1030MODULE_LICENSE("GPL v2");
1031