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