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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * AD714X CapTouch Programmable Controller driver supporting AD7142/3/7/8/7A
4 *
5 * Copyright 2009-2011 Analog Devices Inc.
6 */
7
8#include <linux/device.h>
9#include <linux/input.h>
10#include <linux/interrupt.h>
11#include <linux/slab.h>
12#include <linux/input/ad714x.h>
13#include <linux/module.h>
14#include "ad714x.h"
15
16#define AD714X_PWR_CTRL 0x0
17#define AD714X_STG_CAL_EN_REG 0x1
18#define AD714X_AMB_COMP_CTRL0_REG 0x2
19#define AD714X_PARTID_REG 0x17
20#define AD7142_PARTID 0xE620
21#define AD7143_PARTID 0xE630
22#define AD7147_PARTID 0x1470
23#define AD7148_PARTID 0x1480
24#define AD714X_STAGECFG_REG 0x80
25#define AD714X_SYSCFG_REG 0x0
26
27#define STG_LOW_INT_EN_REG 0x5
28#define STG_HIGH_INT_EN_REG 0x6
29#define STG_COM_INT_EN_REG 0x7
30#define STG_LOW_INT_STA_REG 0x8
31#define STG_HIGH_INT_STA_REG 0x9
32#define STG_COM_INT_STA_REG 0xA
33
34#define CDC_RESULT_S0 0xB
35#define CDC_RESULT_S1 0xC
36#define CDC_RESULT_S2 0xD
37#define CDC_RESULT_S3 0xE
38#define CDC_RESULT_S4 0xF
39#define CDC_RESULT_S5 0x10
40#define CDC_RESULT_S6 0x11
41#define CDC_RESULT_S7 0x12
42#define CDC_RESULT_S8 0x13
43#define CDC_RESULT_S9 0x14
44#define CDC_RESULT_S10 0x15
45#define CDC_RESULT_S11 0x16
46
47#define STAGE0_AMBIENT 0xF1
48#define STAGE1_AMBIENT 0x115
49#define STAGE2_AMBIENT 0x139
50#define STAGE3_AMBIENT 0x15D
51#define STAGE4_AMBIENT 0x181
52#define STAGE5_AMBIENT 0x1A5
53#define STAGE6_AMBIENT 0x1C9
54#define STAGE7_AMBIENT 0x1ED
55#define STAGE8_AMBIENT 0x211
56#define STAGE9_AMBIENT 0x234
57#define STAGE10_AMBIENT 0x259
58#define STAGE11_AMBIENT 0x27D
59
60#define PER_STAGE_REG_NUM 36
61#define STAGE_CFGREG_NUM 8
62#define SYS_CFGREG_NUM 8
63
64/*
65 * driver information which will be used to maintain the software flow
66 */
67enum ad714x_device_state { IDLE, JITTER, ACTIVE, SPACE };
68
69struct ad714x_slider_drv {
70 int highest_stage;
71 int abs_pos;
72 int flt_pos;
73 enum ad714x_device_state state;
74 struct input_dev *input;
75};
76
77struct ad714x_wheel_drv {
78 int abs_pos;
79 int flt_pos;
80 int pre_highest_stage;
81 int highest_stage;
82 enum ad714x_device_state state;
83 struct input_dev *input;
84};
85
86struct ad714x_touchpad_drv {
87 int x_highest_stage;
88 int x_flt_pos;
89 int x_abs_pos;
90 int y_highest_stage;
91 int y_flt_pos;
92 int y_abs_pos;
93 int left_ep;
94 int left_ep_val;
95 int right_ep;
96 int right_ep_val;
97 int top_ep;
98 int top_ep_val;
99 int bottom_ep;
100 int bottom_ep_val;
101 enum ad714x_device_state state;
102 struct input_dev *input;
103};
104
105struct ad714x_button_drv {
106 enum ad714x_device_state state;
107 /*
108 * Unlike slider/wheel/touchpad, all buttons point to
109 * same input_dev instance
110 */
111 struct input_dev *input;
112};
113
114struct ad714x_driver_data {
115 struct ad714x_slider_drv *slider;
116 struct ad714x_wheel_drv *wheel;
117 struct ad714x_touchpad_drv *touchpad;
118 struct ad714x_button_drv *button;
119};
120
121/*
122 * information to integrate all things which will be private data
123 * of spi/i2c device
124 */
125
126static void ad714x_use_com_int(struct ad714x_chip *ad714x,
127 int start_stage, int end_stage)
128{
129 unsigned short data;
130 unsigned short mask;
131
132 mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
133
134 ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
135 data |= 1 << end_stage;
136 ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
137
138 ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
139 data &= ~mask;
140 ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
141}
142
143static void ad714x_use_thr_int(struct ad714x_chip *ad714x,
144 int start_stage, int end_stage)
145{
146 unsigned short data;
147 unsigned short mask;
148
149 mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
150
151 ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
152 data &= ~(1 << end_stage);
153 ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
154
155 ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
156 data |= mask;
157 ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
158}
159
160static int ad714x_cal_highest_stage(struct ad714x_chip *ad714x,
161 int start_stage, int end_stage)
162{
163 int max_res = 0;
164 int max_idx = 0;
165 int i;
166
167 for (i = start_stage; i <= end_stage; i++) {
168 if (ad714x->sensor_val[i] > max_res) {
169 max_res = ad714x->sensor_val[i];
170 max_idx = i;
171 }
172 }
173
174 return max_idx;
175}
176
177static int ad714x_cal_abs_pos(struct ad714x_chip *ad714x,
178 int start_stage, int end_stage,
179 int highest_stage, int max_coord)
180{
181 int a_param, b_param;
182
183 if (highest_stage == start_stage) {
184 a_param = ad714x->sensor_val[start_stage + 1];
185 b_param = ad714x->sensor_val[start_stage] +
186 ad714x->sensor_val[start_stage + 1];
187 } else if (highest_stage == end_stage) {
188 a_param = ad714x->sensor_val[end_stage] *
189 (end_stage - start_stage) +
190 ad714x->sensor_val[end_stage - 1] *
191 (end_stage - start_stage - 1);
192 b_param = ad714x->sensor_val[end_stage] +
193 ad714x->sensor_val[end_stage - 1];
194 } else {
195 a_param = ad714x->sensor_val[highest_stage] *
196 (highest_stage - start_stage) +
197 ad714x->sensor_val[highest_stage - 1] *
198 (highest_stage - start_stage - 1) +
199 ad714x->sensor_val[highest_stage + 1] *
200 (highest_stage - start_stage + 1);
201 b_param = ad714x->sensor_val[highest_stage] +
202 ad714x->sensor_val[highest_stage - 1] +
203 ad714x->sensor_val[highest_stage + 1];
204 }
205
206 return (max_coord / (end_stage - start_stage)) * a_param / b_param;
207}
208
209/*
210 * One button can connect to multi positive and negative of CDCs
211 * Multi-buttons can connect to same positive/negative of one CDC
212 */
213static void ad714x_button_state_machine(struct ad714x_chip *ad714x, int idx)
214{
215 struct ad714x_button_plat *hw = &ad714x->hw->button[idx];
216 struct ad714x_button_drv *sw = &ad714x->sw->button[idx];
217
218 switch (sw->state) {
219 case IDLE:
220 if (((ad714x->h_state & hw->h_mask) == hw->h_mask) &&
221 ((ad714x->l_state & hw->l_mask) == hw->l_mask)) {
222 dev_dbg(ad714x->dev, "button %d touched\n", idx);
223 input_report_key(sw->input, hw->keycode, 1);
224 input_sync(sw->input);
225 sw->state = ACTIVE;
226 }
227 break;
228
229 case ACTIVE:
230 if (((ad714x->h_state & hw->h_mask) != hw->h_mask) ||
231 ((ad714x->l_state & hw->l_mask) != hw->l_mask)) {
232 dev_dbg(ad714x->dev, "button %d released\n", idx);
233 input_report_key(sw->input, hw->keycode, 0);
234 input_sync(sw->input);
235 sw->state = IDLE;
236 }
237 break;
238
239 default:
240 break;
241 }
242}
243
244/*
245 * The response of a sensor is defined by the absolute number of codes
246 * between the current CDC value and the ambient value.
247 */
248static void ad714x_slider_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
249{
250 struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
251 int i;
252
253 ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
254 &ad714x->adc_reg[hw->start_stage],
255 hw->end_stage - hw->start_stage + 1);
256
257 for (i = hw->start_stage; i <= hw->end_stage; i++) {
258 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
259 &ad714x->amb_reg[i], 1);
260
261 ad714x->sensor_val[i] =
262 abs(ad714x->adc_reg[i] - ad714x->amb_reg[i]);
263 }
264}
265
266static void ad714x_slider_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
267{
268 struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
269 struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
270
271 sw->highest_stage = ad714x_cal_highest_stage(ad714x, hw->start_stage,
272 hw->end_stage);
273
274 dev_dbg(ad714x->dev, "slider %d highest_stage:%d\n", idx,
275 sw->highest_stage);
276}
277
278/*
279 * The formulae are very straight forward. It uses the sensor with the
280 * highest response and the 2 adjacent ones.
281 * When Sensor 0 has the highest response, only sensor 0 and sensor 1
282 * are used in the calculations. Similarly when the last sensor has the
283 * highest response, only the last sensor and the second last sensors
284 * are used in the calculations.
285 *
286 * For i= idx_of_peak_Sensor-1 to i= idx_of_peak_Sensor+1
287 * v += Sensor response(i)*i
288 * w += Sensor response(i)
289 * POS=(Number_of_Positions_Wanted/(Number_of_Sensors_Used-1)) *(v/w)
290 */
291static void ad714x_slider_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
292{
293 struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
294 struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
295
296 sw->abs_pos = ad714x_cal_abs_pos(ad714x, hw->start_stage, hw->end_stage,
297 sw->highest_stage, hw->max_coord);
298
299 dev_dbg(ad714x->dev, "slider %d absolute position:%d\n", idx,
300 sw->abs_pos);
301}
302
303/*
304 * To minimise the Impact of the noise on the algorithm, ADI developed a
305 * routine that filters the CDC results after they have been read by the
306 * host processor.
307 * The filter used is an Infinite Input Response(IIR) filter implemented
308 * in firmware and attenuates the noise on the CDC results after they've
309 * been read by the host processor.
310 * Filtered_CDC_result = (Filtered_CDC_result * (10 - Coefficient) +
311 * Latest_CDC_result * Coefficient)/10
312 */
313static void ad714x_slider_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
314{
315 struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
316
317 sw->flt_pos = (sw->flt_pos * (10 - 4) +
318 sw->abs_pos * 4)/10;
319
320 dev_dbg(ad714x->dev, "slider %d filter position:%d\n", idx,
321 sw->flt_pos);
322}
323
324static void ad714x_slider_use_com_int(struct ad714x_chip *ad714x, int idx)
325{
326 struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
327
328 ad714x_use_com_int(ad714x, hw->start_stage, hw->end_stage);
329}
330
331static void ad714x_slider_use_thr_int(struct ad714x_chip *ad714x, int idx)
332{
333 struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
334
335 ad714x_use_thr_int(ad714x, hw->start_stage, hw->end_stage);
336}
337
338static void ad714x_slider_state_machine(struct ad714x_chip *ad714x, int idx)
339{
340 struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
341 struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
342 unsigned short h_state, c_state;
343 unsigned short mask;
344
345 mask = ((1 << (hw->end_stage + 1)) - 1) - ((1 << hw->start_stage) - 1);
346
347 h_state = ad714x->h_state & mask;
348 c_state = ad714x->c_state & mask;
349
350 switch (sw->state) {
351 case IDLE:
352 if (h_state) {
353 sw->state = JITTER;
354 /* In End of Conversion interrupt mode, the AD714X
355 * continuously generates hardware interrupts.
356 */
357 ad714x_slider_use_com_int(ad714x, idx);
358 dev_dbg(ad714x->dev, "slider %d touched\n", idx);
359 }
360 break;
361
362 case JITTER:
363 if (c_state == mask) {
364 ad714x_slider_cal_sensor_val(ad714x, idx);
365 ad714x_slider_cal_highest_stage(ad714x, idx);
366 ad714x_slider_cal_abs_pos(ad714x, idx);
367 sw->flt_pos = sw->abs_pos;
368 sw->state = ACTIVE;
369 }
370 break;
371
372 case ACTIVE:
373 if (c_state == mask) {
374 if (h_state) {
375 ad714x_slider_cal_sensor_val(ad714x, idx);
376 ad714x_slider_cal_highest_stage(ad714x, idx);
377 ad714x_slider_cal_abs_pos(ad714x, idx);
378 ad714x_slider_cal_flt_pos(ad714x, idx);
379 input_report_abs(sw->input, ABS_X, sw->flt_pos);
380 input_report_key(sw->input, BTN_TOUCH, 1);
381 } else {
382 /* When the user lifts off the sensor, configure
383 * the AD714X back to threshold interrupt mode.
384 */
385 ad714x_slider_use_thr_int(ad714x, idx);
386 sw->state = IDLE;
387 input_report_key(sw->input, BTN_TOUCH, 0);
388 dev_dbg(ad714x->dev, "slider %d released\n",
389 idx);
390 }
391 input_sync(sw->input);
392 }
393 break;
394
395 default:
396 break;
397 }
398}
399
400/*
401 * When the scroll wheel is activated, we compute the absolute position based
402 * on the sensor values. To calculate the position, we first determine the
403 * sensor that has the greatest response among the 8 sensors that constitutes
404 * the scrollwheel. Then we determined the 2 sensors on either sides of the
405 * sensor with the highest response and we apply weights to these sensors.
406 */
407static void ad714x_wheel_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
408{
409 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
410 struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
411
412 sw->pre_highest_stage = sw->highest_stage;
413 sw->highest_stage = ad714x_cal_highest_stage(ad714x, hw->start_stage,
414 hw->end_stage);
415
416 dev_dbg(ad714x->dev, "wheel %d highest_stage:%d\n", idx,
417 sw->highest_stage);
418}
419
420static void ad714x_wheel_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
421{
422 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
423 int i;
424
425 ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
426 &ad714x->adc_reg[hw->start_stage],
427 hw->end_stage - hw->start_stage + 1);
428
429 for (i = hw->start_stage; i <= hw->end_stage; i++) {
430 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
431 &ad714x->amb_reg[i], 1);
432 if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
433 ad714x->sensor_val[i] =
434 ad714x->adc_reg[i] - ad714x->amb_reg[i];
435 else
436 ad714x->sensor_val[i] = 0;
437 }
438}
439
440/*
441 * When the scroll wheel is activated, we compute the absolute position based
442 * on the sensor values. To calculate the position, we first determine the
443 * sensor that has the greatest response among the sensors that constitutes
444 * the scrollwheel. Then we determined the sensors on either sides of the
445 * sensor with the highest response and we apply weights to these sensors. The
446 * result of this computation gives us the mean value.
447 */
448
449static void ad714x_wheel_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
450{
451 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
452 struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
453 int stage_num = hw->end_stage - hw->start_stage + 1;
454 int first_before, highest, first_after;
455 int a_param, b_param;
456
457 first_before = (sw->highest_stage + stage_num - 1) % stage_num;
458 highest = sw->highest_stage;
459 first_after = (sw->highest_stage + stage_num + 1) % stage_num;
460
461 a_param = ad714x->sensor_val[highest] *
462 (highest - hw->start_stage) +
463 ad714x->sensor_val[first_before] *
464 (highest - hw->start_stage - 1) +
465 ad714x->sensor_val[first_after] *
466 (highest - hw->start_stage + 1);
467 b_param = ad714x->sensor_val[highest] +
468 ad714x->sensor_val[first_before] +
469 ad714x->sensor_val[first_after];
470
471 sw->abs_pos = ((hw->max_coord / (hw->end_stage - hw->start_stage)) *
472 a_param) / b_param;
473
474 if (sw->abs_pos > hw->max_coord)
475 sw->abs_pos = hw->max_coord;
476 else if (sw->abs_pos < 0)
477 sw->abs_pos = 0;
478}
479
480static void ad714x_wheel_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
481{
482 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
483 struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
484 if (((sw->pre_highest_stage == hw->end_stage) &&
485 (sw->highest_stage == hw->start_stage)) ||
486 ((sw->pre_highest_stage == hw->start_stage) &&
487 (sw->highest_stage == hw->end_stage)))
488 sw->flt_pos = sw->abs_pos;
489 else
490 sw->flt_pos = ((sw->flt_pos * 30) + (sw->abs_pos * 71)) / 100;
491
492 if (sw->flt_pos > hw->max_coord)
493 sw->flt_pos = hw->max_coord;
494}
495
496static void ad714x_wheel_use_com_int(struct ad714x_chip *ad714x, int idx)
497{
498 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
499
500 ad714x_use_com_int(ad714x, hw->start_stage, hw->end_stage);
501}
502
503static void ad714x_wheel_use_thr_int(struct ad714x_chip *ad714x, int idx)
504{
505 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
506
507 ad714x_use_thr_int(ad714x, hw->start_stage, hw->end_stage);
508}
509
510static void ad714x_wheel_state_machine(struct ad714x_chip *ad714x, int idx)
511{
512 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
513 struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
514 unsigned short h_state, c_state;
515 unsigned short mask;
516
517 mask = ((1 << (hw->end_stage + 1)) - 1) - ((1 << hw->start_stage) - 1);
518
519 h_state = ad714x->h_state & mask;
520 c_state = ad714x->c_state & mask;
521
522 switch (sw->state) {
523 case IDLE:
524 if (h_state) {
525 sw->state = JITTER;
526 /* In End of Conversion interrupt mode, the AD714X
527 * continuously generates hardware interrupts.
528 */
529 ad714x_wheel_use_com_int(ad714x, idx);
530 dev_dbg(ad714x->dev, "wheel %d touched\n", idx);
531 }
532 break;
533
534 case JITTER:
535 if (c_state == mask) {
536 ad714x_wheel_cal_sensor_val(ad714x, idx);
537 ad714x_wheel_cal_highest_stage(ad714x, idx);
538 ad714x_wheel_cal_abs_pos(ad714x, idx);
539 sw->flt_pos = sw->abs_pos;
540 sw->state = ACTIVE;
541 }
542 break;
543
544 case ACTIVE:
545 if (c_state == mask) {
546 if (h_state) {
547 ad714x_wheel_cal_sensor_val(ad714x, idx);
548 ad714x_wheel_cal_highest_stage(ad714x, idx);
549 ad714x_wheel_cal_abs_pos(ad714x, idx);
550 ad714x_wheel_cal_flt_pos(ad714x, idx);
551 input_report_abs(sw->input, ABS_WHEEL,
552 sw->flt_pos);
553 input_report_key(sw->input, BTN_TOUCH, 1);
554 } else {
555 /* When the user lifts off the sensor, configure
556 * the AD714X back to threshold interrupt mode.
557 */
558 ad714x_wheel_use_thr_int(ad714x, idx);
559 sw->state = IDLE;
560 input_report_key(sw->input, BTN_TOUCH, 0);
561
562 dev_dbg(ad714x->dev, "wheel %d released\n",
563 idx);
564 }
565 input_sync(sw->input);
566 }
567 break;
568
569 default:
570 break;
571 }
572}
573
574static void touchpad_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
575{
576 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
577 int i;
578
579 ad714x->read(ad714x, CDC_RESULT_S0 + hw->x_start_stage,
580 &ad714x->adc_reg[hw->x_start_stage],
581 hw->x_end_stage - hw->x_start_stage + 1);
582
583 for (i = hw->x_start_stage; i <= hw->x_end_stage; i++) {
584 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
585 &ad714x->amb_reg[i], 1);
586 if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
587 ad714x->sensor_val[i] =
588 ad714x->adc_reg[i] - ad714x->amb_reg[i];
589 else
590 ad714x->sensor_val[i] = 0;
591 }
592}
593
594static void touchpad_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
595{
596 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
597 struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
598
599 sw->x_highest_stage = ad714x_cal_highest_stage(ad714x,
600 hw->x_start_stage, hw->x_end_stage);
601 sw->y_highest_stage = ad714x_cal_highest_stage(ad714x,
602 hw->y_start_stage, hw->y_end_stage);
603
604 dev_dbg(ad714x->dev,
605 "touchpad %d x_highest_stage:%d, y_highest_stage:%d\n",
606 idx, sw->x_highest_stage, sw->y_highest_stage);
607}
608
609/*
610 * If 2 fingers are touching the sensor then 2 peaks can be observed in the
611 * distribution.
612 * The arithmetic doesn't support to get absolute coordinates for multi-touch
613 * yet.
614 */
615static int touchpad_check_second_peak(struct ad714x_chip *ad714x, int idx)
616{
617 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
618 struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
619 int i;
620
621 for (i = hw->x_start_stage; i < sw->x_highest_stage; i++) {
622 if ((ad714x->sensor_val[i] - ad714x->sensor_val[i + 1])
623 > (ad714x->sensor_val[i + 1] / 10))
624 return 1;
625 }
626
627 for (i = sw->x_highest_stage; i < hw->x_end_stage; i++) {
628 if ((ad714x->sensor_val[i + 1] - ad714x->sensor_val[i])
629 > (ad714x->sensor_val[i] / 10))
630 return 1;
631 }
632
633 for (i = hw->y_start_stage; i < sw->y_highest_stage; i++) {
634 if ((ad714x->sensor_val[i] - ad714x->sensor_val[i + 1])
635 > (ad714x->sensor_val[i + 1] / 10))
636 return 1;
637 }
638
639 for (i = sw->y_highest_stage; i < hw->y_end_stage; i++) {
640 if ((ad714x->sensor_val[i + 1] - ad714x->sensor_val[i])
641 > (ad714x->sensor_val[i] / 10))
642 return 1;
643 }
644
645 return 0;
646}
647
648/*
649 * If only one finger is used to activate the touch pad then only 1 peak will be
650 * registered in the distribution. This peak and the 2 adjacent sensors will be
651 * used in the calculation of the absolute position. This will prevent hand
652 * shadows to affect the absolute position calculation.
653 */
654static void touchpad_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
655{
656 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
657 struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
658
659 sw->x_abs_pos = ad714x_cal_abs_pos(ad714x, hw->x_start_stage,
660 hw->x_end_stage, sw->x_highest_stage, hw->x_max_coord);
661 sw->y_abs_pos = ad714x_cal_abs_pos(ad714x, hw->y_start_stage,
662 hw->y_end_stage, sw->y_highest_stage, hw->y_max_coord);
663
664 dev_dbg(ad714x->dev, "touchpad %d absolute position:(%d, %d)\n", idx,
665 sw->x_abs_pos, sw->y_abs_pos);
666}
667
668static void touchpad_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
669{
670 struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
671
672 sw->x_flt_pos = (sw->x_flt_pos * (10 - 4) +
673 sw->x_abs_pos * 4)/10;
674 sw->y_flt_pos = (sw->y_flt_pos * (10 - 4) +
675 sw->y_abs_pos * 4)/10;
676
677 dev_dbg(ad714x->dev, "touchpad %d filter position:(%d, %d)\n",
678 idx, sw->x_flt_pos, sw->y_flt_pos);
679}
680
681/*
682 * To prevent distortion from showing in the absolute position, it is
683 * necessary to detect the end points. When endpoints are detected, the
684 * driver stops updating the status variables with absolute positions.
685 * End points are detected on the 4 edges of the touchpad sensor. The
686 * method to detect them is the same for all 4.
687 * To detect the end points, the firmware computes the difference in
688 * percent between the sensor on the edge and the adjacent one. The
689 * difference is calculated in percent in order to make the end point
690 * detection independent of the pressure.
691 */
692
693#define LEFT_END_POINT_DETECTION_LEVEL 550
694#define RIGHT_END_POINT_DETECTION_LEVEL 750
695#define LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL 850
696#define TOP_END_POINT_DETECTION_LEVEL 550
697#define BOTTOM_END_POINT_DETECTION_LEVEL 950
698#define TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL 700
699static int touchpad_check_endpoint(struct ad714x_chip *ad714x, int idx)
700{
701 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
702 struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
703 int percent_sensor_diff;
704
705 /* left endpoint detect */
706 percent_sensor_diff = (ad714x->sensor_val[hw->x_start_stage] -
707 ad714x->sensor_val[hw->x_start_stage + 1]) * 100 /
708 ad714x->sensor_val[hw->x_start_stage + 1];
709 if (!sw->left_ep) {
710 if (percent_sensor_diff >= LEFT_END_POINT_DETECTION_LEVEL) {
711 sw->left_ep = 1;
712 sw->left_ep_val =
713 ad714x->sensor_val[hw->x_start_stage + 1];
714 }
715 } else {
716 if ((percent_sensor_diff < LEFT_END_POINT_DETECTION_LEVEL) &&
717 (ad714x->sensor_val[hw->x_start_stage + 1] >
718 LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL + sw->left_ep_val))
719 sw->left_ep = 0;
720 }
721
722 /* right endpoint detect */
723 percent_sensor_diff = (ad714x->sensor_val[hw->x_end_stage] -
724 ad714x->sensor_val[hw->x_end_stage - 1]) * 100 /
725 ad714x->sensor_val[hw->x_end_stage - 1];
726 if (!sw->right_ep) {
727 if (percent_sensor_diff >= RIGHT_END_POINT_DETECTION_LEVEL) {
728 sw->right_ep = 1;
729 sw->right_ep_val =
730 ad714x->sensor_val[hw->x_end_stage - 1];
731 }
732 } else {
733 if ((percent_sensor_diff < RIGHT_END_POINT_DETECTION_LEVEL) &&
734 (ad714x->sensor_val[hw->x_end_stage - 1] >
735 LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL + sw->right_ep_val))
736 sw->right_ep = 0;
737 }
738
739 /* top endpoint detect */
740 percent_sensor_diff = (ad714x->sensor_val[hw->y_start_stage] -
741 ad714x->sensor_val[hw->y_start_stage + 1]) * 100 /
742 ad714x->sensor_val[hw->y_start_stage + 1];
743 if (!sw->top_ep) {
744 if (percent_sensor_diff >= TOP_END_POINT_DETECTION_LEVEL) {
745 sw->top_ep = 1;
746 sw->top_ep_val =
747 ad714x->sensor_val[hw->y_start_stage + 1];
748 }
749 } else {
750 if ((percent_sensor_diff < TOP_END_POINT_DETECTION_LEVEL) &&
751 (ad714x->sensor_val[hw->y_start_stage + 1] >
752 TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL + sw->top_ep_val))
753 sw->top_ep = 0;
754 }
755
756 /* bottom endpoint detect */
757 percent_sensor_diff = (ad714x->sensor_val[hw->y_end_stage] -
758 ad714x->sensor_val[hw->y_end_stage - 1]) * 100 /
759 ad714x->sensor_val[hw->y_end_stage - 1];
760 if (!sw->bottom_ep) {
761 if (percent_sensor_diff >= BOTTOM_END_POINT_DETECTION_LEVEL) {
762 sw->bottom_ep = 1;
763 sw->bottom_ep_val =
764 ad714x->sensor_val[hw->y_end_stage - 1];
765 }
766 } else {
767 if ((percent_sensor_diff < BOTTOM_END_POINT_DETECTION_LEVEL) &&
768 (ad714x->sensor_val[hw->y_end_stage - 1] >
769 TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL + sw->bottom_ep_val))
770 sw->bottom_ep = 0;
771 }
772
773 return sw->left_ep || sw->right_ep || sw->top_ep || sw->bottom_ep;
774}
775
776static void touchpad_use_com_int(struct ad714x_chip *ad714x, int idx)
777{
778 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
779
780 ad714x_use_com_int(ad714x, hw->x_start_stage, hw->x_end_stage);
781}
782
783static void touchpad_use_thr_int(struct ad714x_chip *ad714x, int idx)
784{
785 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
786
787 ad714x_use_thr_int(ad714x, hw->x_start_stage, hw->x_end_stage);
788 ad714x_use_thr_int(ad714x, hw->y_start_stage, hw->y_end_stage);
789}
790
791static void ad714x_touchpad_state_machine(struct ad714x_chip *ad714x, int idx)
792{
793 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
794 struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
795 unsigned short h_state, c_state;
796 unsigned short mask;
797
798 mask = (((1 << (hw->x_end_stage + 1)) - 1) -
799 ((1 << hw->x_start_stage) - 1)) +
800 (((1 << (hw->y_end_stage + 1)) - 1) -
801 ((1 << hw->y_start_stage) - 1));
802
803 h_state = ad714x->h_state & mask;
804 c_state = ad714x->c_state & mask;
805
806 switch (sw->state) {
807 case IDLE:
808 if (h_state) {
809 sw->state = JITTER;
810 /* In End of Conversion interrupt mode, the AD714X
811 * continuously generates hardware interrupts.
812 */
813 touchpad_use_com_int(ad714x, idx);
814 dev_dbg(ad714x->dev, "touchpad %d touched\n", idx);
815 }
816 break;
817
818 case JITTER:
819 if (c_state == mask) {
820 touchpad_cal_sensor_val(ad714x, idx);
821 touchpad_cal_highest_stage(ad714x, idx);
822 if ((!touchpad_check_second_peak(ad714x, idx)) &&
823 (!touchpad_check_endpoint(ad714x, idx))) {
824 dev_dbg(ad714x->dev,
825 "touchpad%d, 2 fingers or endpoint\n",
826 idx);
827 touchpad_cal_abs_pos(ad714x, idx);
828 sw->x_flt_pos = sw->x_abs_pos;
829 sw->y_flt_pos = sw->y_abs_pos;
830 sw->state = ACTIVE;
831 }
832 }
833 break;
834
835 case ACTIVE:
836 if (c_state == mask) {
837 if (h_state) {
838 touchpad_cal_sensor_val(ad714x, idx);
839 touchpad_cal_highest_stage(ad714x, idx);
840 if ((!touchpad_check_second_peak(ad714x, idx))
841 && (!touchpad_check_endpoint(ad714x, idx))) {
842 touchpad_cal_abs_pos(ad714x, idx);
843 touchpad_cal_flt_pos(ad714x, idx);
844 input_report_abs(sw->input, ABS_X,
845 sw->x_flt_pos);
846 input_report_abs(sw->input, ABS_Y,
847 sw->y_flt_pos);
848 input_report_key(sw->input, BTN_TOUCH,
849 1);
850 }
851 } else {
852 /* When the user lifts off the sensor, configure
853 * the AD714X back to threshold interrupt mode.
854 */
855 touchpad_use_thr_int(ad714x, idx);
856 sw->state = IDLE;
857 input_report_key(sw->input, BTN_TOUCH, 0);
858 dev_dbg(ad714x->dev, "touchpad %d released\n",
859 idx);
860 }
861 input_sync(sw->input);
862 }
863 break;
864
865 default:
866 break;
867 }
868}
869
870static int ad714x_hw_detect(struct ad714x_chip *ad714x)
871{
872 unsigned short data;
873
874 ad714x->read(ad714x, AD714X_PARTID_REG, &data, 1);
875 switch (data & 0xFFF0) {
876 case AD7142_PARTID:
877 ad714x->product = 0x7142;
878 ad714x->version = data & 0xF;
879 dev_info(ad714x->dev, "found AD7142 captouch, rev:%d\n",
880 ad714x->version);
881 return 0;
882
883 case AD7143_PARTID:
884 ad714x->product = 0x7143;
885 ad714x->version = data & 0xF;
886 dev_info(ad714x->dev, "found AD7143 captouch, rev:%d\n",
887 ad714x->version);
888 return 0;
889
890 case AD7147_PARTID:
891 ad714x->product = 0x7147;
892 ad714x->version = data & 0xF;
893 dev_info(ad714x->dev, "found AD7147(A) captouch, rev:%d\n",
894 ad714x->version);
895 return 0;
896
897 case AD7148_PARTID:
898 ad714x->product = 0x7148;
899 ad714x->version = data & 0xF;
900 dev_info(ad714x->dev, "found AD7148 captouch, rev:%d\n",
901 ad714x->version);
902 return 0;
903
904 default:
905 dev_err(ad714x->dev,
906 "fail to detect AD714X captouch, read ID is %04x\n",
907 data);
908 return -ENODEV;
909 }
910}
911
912static void ad714x_hw_init(struct ad714x_chip *ad714x)
913{
914 int i, j;
915 unsigned short reg_base;
916 unsigned short data;
917
918 /* configuration CDC and interrupts */
919
920 for (i = 0; i < STAGE_NUM; i++) {
921 reg_base = AD714X_STAGECFG_REG + i * STAGE_CFGREG_NUM;
922 for (j = 0; j < STAGE_CFGREG_NUM; j++)
923 ad714x->write(ad714x, reg_base + j,
924 ad714x->hw->stage_cfg_reg[i][j]);
925 }
926
927 for (i = 0; i < SYS_CFGREG_NUM; i++)
928 ad714x->write(ad714x, AD714X_SYSCFG_REG + i,
929 ad714x->hw->sys_cfg_reg[i]);
930 for (i = 0; i < SYS_CFGREG_NUM; i++)
931 ad714x->read(ad714x, AD714X_SYSCFG_REG + i, &data, 1);
932
933 ad714x->write(ad714x, AD714X_STG_CAL_EN_REG, 0xFFF);
934
935 /* clear all interrupts */
936 ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
937}
938
939static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
940{
941 struct ad714x_chip *ad714x = data;
942 int i;
943
944 mutex_lock(&ad714x->mutex);
945
946 ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
947
948 for (i = 0; i < ad714x->hw->button_num; i++)
949 ad714x_button_state_machine(ad714x, i);
950 for (i = 0; i < ad714x->hw->slider_num; i++)
951 ad714x_slider_state_machine(ad714x, i);
952 for (i = 0; i < ad714x->hw->wheel_num; i++)
953 ad714x_wheel_state_machine(ad714x, i);
954 for (i = 0; i < ad714x->hw->touchpad_num; i++)
955 ad714x_touchpad_state_machine(ad714x, i);
956
957 mutex_unlock(&ad714x->mutex);
958
959 return IRQ_HANDLED;
960}
961
962struct ad714x_chip *ad714x_probe(struct device *dev, u16 bus_type, int irq,
963 ad714x_read_t read, ad714x_write_t write)
964{
965 int i;
966 int error;
967 struct input_dev *input;
968
969 struct ad714x_platform_data *plat_data = dev_get_platdata(dev);
970 struct ad714x_chip *ad714x;
971 void *drv_mem;
972 unsigned long irqflags;
973
974 struct ad714x_button_drv *bt_drv;
975 struct ad714x_slider_drv *sd_drv;
976 struct ad714x_wheel_drv *wl_drv;
977 struct ad714x_touchpad_drv *tp_drv;
978
979
980 if (irq <= 0) {
981 dev_err(dev, "IRQ not configured!\n");
982 error = -EINVAL;
983 return ERR_PTR(error);
984 }
985
986 if (dev_get_platdata(dev) == NULL) {
987 dev_err(dev, "platform data for ad714x doesn't exist\n");
988 error = -EINVAL;
989 return ERR_PTR(error);
990 }
991
992 ad714x = devm_kzalloc(dev, sizeof(*ad714x) + sizeof(*ad714x->sw) +
993 sizeof(*sd_drv) * plat_data->slider_num +
994 sizeof(*wl_drv) * plat_data->wheel_num +
995 sizeof(*tp_drv) * plat_data->touchpad_num +
996 sizeof(*bt_drv) * plat_data->button_num,
997 GFP_KERNEL);
998 if (!ad714x) {
999 error = -ENOMEM;
1000 return ERR_PTR(error);
1001 }
1002 ad714x->hw = plat_data;
1003
1004 drv_mem = ad714x + 1;
1005 ad714x->sw = drv_mem;
1006 drv_mem += sizeof(*ad714x->sw);
1007 ad714x->sw->slider = sd_drv = drv_mem;
1008 drv_mem += sizeof(*sd_drv) * ad714x->hw->slider_num;
1009 ad714x->sw->wheel = wl_drv = drv_mem;
1010 drv_mem += sizeof(*wl_drv) * ad714x->hw->wheel_num;
1011 ad714x->sw->touchpad = tp_drv = drv_mem;
1012 drv_mem += sizeof(*tp_drv) * ad714x->hw->touchpad_num;
1013 ad714x->sw->button = bt_drv = drv_mem;
1014 drv_mem += sizeof(*bt_drv) * ad714x->hw->button_num;
1015
1016 ad714x->read = read;
1017 ad714x->write = write;
1018 ad714x->irq = irq;
1019 ad714x->dev = dev;
1020
1021 error = ad714x_hw_detect(ad714x);
1022 if (error)
1023 return ERR_PTR(error);
1024
1025 /* initialize and request sw/hw resources */
1026
1027 ad714x_hw_init(ad714x);
1028 mutex_init(&ad714x->mutex);
1029
1030 /* a slider uses one input_dev instance */
1031 if (ad714x->hw->slider_num > 0) {
1032 struct ad714x_slider_plat *sd_plat = ad714x->hw->slider;
1033
1034 for (i = 0; i < ad714x->hw->slider_num; i++) {
1035 input = devm_input_allocate_device(dev);
1036 if (!input)
1037 return ERR_PTR(-ENOMEM);
1038
1039 __set_bit(EV_ABS, input->evbit);
1040 __set_bit(EV_KEY, input->evbit);
1041 __set_bit(ABS_X, input->absbit);
1042 __set_bit(BTN_TOUCH, input->keybit);
1043 input_set_abs_params(input,
1044 ABS_X, 0, sd_plat->max_coord, 0, 0);
1045
1046 input->id.bustype = bus_type;
1047 input->id.product = ad714x->product;
1048 input->id.version = ad714x->version;
1049 input->name = "ad714x_captouch_slider";
1050 input->dev.parent = dev;
1051
1052 error = input_register_device(input);
1053 if (error)
1054 return ERR_PTR(error);
1055
1056 sd_drv[i].input = input;
1057 }
1058 }
1059
1060 /* a wheel uses one input_dev instance */
1061 if (ad714x->hw->wheel_num > 0) {
1062 struct ad714x_wheel_plat *wl_plat = ad714x->hw->wheel;
1063
1064 for (i = 0; i < ad714x->hw->wheel_num; i++) {
1065 input = devm_input_allocate_device(dev);
1066 if (!input)
1067 return ERR_PTR(-ENOMEM);
1068
1069 __set_bit(EV_KEY, input->evbit);
1070 __set_bit(EV_ABS, input->evbit);
1071 __set_bit(ABS_WHEEL, input->absbit);
1072 __set_bit(BTN_TOUCH, input->keybit);
1073 input_set_abs_params(input,
1074 ABS_WHEEL, 0, wl_plat->max_coord, 0, 0);
1075
1076 input->id.bustype = bus_type;
1077 input->id.product = ad714x->product;
1078 input->id.version = ad714x->version;
1079 input->name = "ad714x_captouch_wheel";
1080 input->dev.parent = dev;
1081
1082 error = input_register_device(input);
1083 if (error)
1084 return ERR_PTR(error);
1085
1086 wl_drv[i].input = input;
1087 }
1088 }
1089
1090 /* a touchpad uses one input_dev instance */
1091 if (ad714x->hw->touchpad_num > 0) {
1092 struct ad714x_touchpad_plat *tp_plat = ad714x->hw->touchpad;
1093
1094 for (i = 0; i < ad714x->hw->touchpad_num; i++) {
1095 input = devm_input_allocate_device(dev);
1096 if (!input)
1097 return ERR_PTR(-ENOMEM);
1098
1099 __set_bit(EV_ABS, input->evbit);
1100 __set_bit(EV_KEY, input->evbit);
1101 __set_bit(ABS_X, input->absbit);
1102 __set_bit(ABS_Y, input->absbit);
1103 __set_bit(BTN_TOUCH, input->keybit);
1104 input_set_abs_params(input,
1105 ABS_X, 0, tp_plat->x_max_coord, 0, 0);
1106 input_set_abs_params(input,
1107 ABS_Y, 0, tp_plat->y_max_coord, 0, 0);
1108
1109 input->id.bustype = bus_type;
1110 input->id.product = ad714x->product;
1111 input->id.version = ad714x->version;
1112 input->name = "ad714x_captouch_pad";
1113 input->dev.parent = dev;
1114
1115 error = input_register_device(input);
1116 if (error)
1117 return ERR_PTR(error);
1118
1119 tp_drv[i].input = input;
1120 }
1121 }
1122
1123 /* all buttons use one input node */
1124 if (ad714x->hw->button_num > 0) {
1125 struct ad714x_button_plat *bt_plat = ad714x->hw->button;
1126
1127 input = devm_input_allocate_device(dev);
1128 if (!input) {
1129 error = -ENOMEM;
1130 return ERR_PTR(error);
1131 }
1132
1133 __set_bit(EV_KEY, input->evbit);
1134 for (i = 0; i < ad714x->hw->button_num; i++) {
1135 bt_drv[i].input = input;
1136 __set_bit(bt_plat[i].keycode, input->keybit);
1137 }
1138
1139 input->id.bustype = bus_type;
1140 input->id.product = ad714x->product;
1141 input->id.version = ad714x->version;
1142 input->name = "ad714x_captouch_button";
1143 input->dev.parent = dev;
1144
1145 error = input_register_device(input);
1146 if (error)
1147 return ERR_PTR(error);
1148 }
1149
1150 irqflags = plat_data->irqflags ?: IRQF_TRIGGER_FALLING;
1151 irqflags |= IRQF_ONESHOT;
1152
1153 error = devm_request_threaded_irq(dev, ad714x->irq, NULL,
1154 ad714x_interrupt_thread,
1155 irqflags, "ad714x_captouch", ad714x);
1156 if (error) {
1157 dev_err(dev, "can't allocate irq %d\n", ad714x->irq);
1158 return ERR_PTR(error);
1159 }
1160
1161 return ad714x;
1162}
1163EXPORT_SYMBOL(ad714x_probe);
1164
1165static int ad714x_suspend(struct device *dev)
1166{
1167 struct ad714x_chip *ad714x = dev_get_drvdata(dev);
1168 unsigned short data;
1169
1170 dev_dbg(ad714x->dev, "%s enter\n", __func__);
1171
1172 mutex_lock(&ad714x->mutex);
1173
1174 data = ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL] | 0x3;
1175 ad714x->write(ad714x, AD714X_PWR_CTRL, data);
1176
1177 mutex_unlock(&ad714x->mutex);
1178
1179 return 0;
1180}
1181
1182static int ad714x_resume(struct device *dev)
1183{
1184 struct ad714x_chip *ad714x = dev_get_drvdata(dev);
1185 dev_dbg(ad714x->dev, "%s enter\n", __func__);
1186
1187 mutex_lock(&ad714x->mutex);
1188
1189 /* resume to non-shutdown mode */
1190
1191 ad714x->write(ad714x, AD714X_PWR_CTRL,
1192 ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL]);
1193
1194 /* make sure the interrupt output line is not low level after resume,
1195 * otherwise we will get no chance to enter falling-edge irq again
1196 */
1197
1198 ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
1199
1200 mutex_unlock(&ad714x->mutex);
1201
1202 return 0;
1203}
1204
1205EXPORT_SIMPLE_DEV_PM_OPS(ad714x_pm, ad714x_suspend, ad714x_resume);
1206
1207MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor Driver");
1208MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
1209MODULE_LICENSE("GPL");
1/*
2 * AD714X CapTouch Programmable Controller driver supporting AD7142/3/7/8/7A
3 *
4 * Copyright 2009-2011 Analog Devices Inc.
5 *
6 * Licensed under the GPL-2 or later.
7 */
8
9#include <linux/device.h>
10#include <linux/init.h>
11#include <linux/input.h>
12#include <linux/interrupt.h>
13#include <linux/slab.h>
14#include <linux/input/ad714x.h>
15#include <linux/module.h>
16#include "ad714x.h"
17
18#define AD714X_PWR_CTRL 0x0
19#define AD714X_STG_CAL_EN_REG 0x1
20#define AD714X_AMB_COMP_CTRL0_REG 0x2
21#define AD714X_PARTID_REG 0x17
22#define AD7142_PARTID 0xE620
23#define AD7143_PARTID 0xE630
24#define AD7147_PARTID 0x1470
25#define AD7148_PARTID 0x1480
26#define AD714X_STAGECFG_REG 0x80
27#define AD714X_SYSCFG_REG 0x0
28
29#define STG_LOW_INT_EN_REG 0x5
30#define STG_HIGH_INT_EN_REG 0x6
31#define STG_COM_INT_EN_REG 0x7
32#define STG_LOW_INT_STA_REG 0x8
33#define STG_HIGH_INT_STA_REG 0x9
34#define STG_COM_INT_STA_REG 0xA
35
36#define CDC_RESULT_S0 0xB
37#define CDC_RESULT_S1 0xC
38#define CDC_RESULT_S2 0xD
39#define CDC_RESULT_S3 0xE
40#define CDC_RESULT_S4 0xF
41#define CDC_RESULT_S5 0x10
42#define CDC_RESULT_S6 0x11
43#define CDC_RESULT_S7 0x12
44#define CDC_RESULT_S8 0x13
45#define CDC_RESULT_S9 0x14
46#define CDC_RESULT_S10 0x15
47#define CDC_RESULT_S11 0x16
48
49#define STAGE0_AMBIENT 0xF1
50#define STAGE1_AMBIENT 0x115
51#define STAGE2_AMBIENT 0x139
52#define STAGE3_AMBIENT 0x15D
53#define STAGE4_AMBIENT 0x181
54#define STAGE5_AMBIENT 0x1A5
55#define STAGE6_AMBIENT 0x1C9
56#define STAGE7_AMBIENT 0x1ED
57#define STAGE8_AMBIENT 0x211
58#define STAGE9_AMBIENT 0x234
59#define STAGE10_AMBIENT 0x259
60#define STAGE11_AMBIENT 0x27D
61
62#define PER_STAGE_REG_NUM 36
63#define STAGE_CFGREG_NUM 8
64#define SYS_CFGREG_NUM 8
65
66/*
67 * driver information which will be used to maintain the software flow
68 */
69enum ad714x_device_state { IDLE, JITTER, ACTIVE, SPACE };
70
71struct ad714x_slider_drv {
72 int highest_stage;
73 int abs_pos;
74 int flt_pos;
75 enum ad714x_device_state state;
76 struct input_dev *input;
77};
78
79struct ad714x_wheel_drv {
80 int abs_pos;
81 int flt_pos;
82 int pre_highest_stage;
83 int highest_stage;
84 enum ad714x_device_state state;
85 struct input_dev *input;
86};
87
88struct ad714x_touchpad_drv {
89 int x_highest_stage;
90 int x_flt_pos;
91 int x_abs_pos;
92 int y_highest_stage;
93 int y_flt_pos;
94 int y_abs_pos;
95 int left_ep;
96 int left_ep_val;
97 int right_ep;
98 int right_ep_val;
99 int top_ep;
100 int top_ep_val;
101 int bottom_ep;
102 int bottom_ep_val;
103 enum ad714x_device_state state;
104 struct input_dev *input;
105};
106
107struct ad714x_button_drv {
108 enum ad714x_device_state state;
109 /*
110 * Unlike slider/wheel/touchpad, all buttons point to
111 * same input_dev instance
112 */
113 struct input_dev *input;
114};
115
116struct ad714x_driver_data {
117 struct ad714x_slider_drv *slider;
118 struct ad714x_wheel_drv *wheel;
119 struct ad714x_touchpad_drv *touchpad;
120 struct ad714x_button_drv *button;
121};
122
123/*
124 * information to integrate all things which will be private data
125 * of spi/i2c device
126 */
127
128static void ad714x_use_com_int(struct ad714x_chip *ad714x,
129 int start_stage, int end_stage)
130{
131 unsigned short data;
132 unsigned short mask;
133
134 mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
135
136 ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
137 data |= 1 << end_stage;
138 ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
139
140 ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
141 data &= ~mask;
142 ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
143}
144
145static void ad714x_use_thr_int(struct ad714x_chip *ad714x,
146 int start_stage, int end_stage)
147{
148 unsigned short data;
149 unsigned short mask;
150
151 mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
152
153 ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
154 data &= ~(1 << end_stage);
155 ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
156
157 ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
158 data |= mask;
159 ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
160}
161
162static int ad714x_cal_highest_stage(struct ad714x_chip *ad714x,
163 int start_stage, int end_stage)
164{
165 int max_res = 0;
166 int max_idx = 0;
167 int i;
168
169 for (i = start_stage; i <= end_stage; i++) {
170 if (ad714x->sensor_val[i] > max_res) {
171 max_res = ad714x->sensor_val[i];
172 max_idx = i;
173 }
174 }
175
176 return max_idx;
177}
178
179static int ad714x_cal_abs_pos(struct ad714x_chip *ad714x,
180 int start_stage, int end_stage,
181 int highest_stage, int max_coord)
182{
183 int a_param, b_param;
184
185 if (highest_stage == start_stage) {
186 a_param = ad714x->sensor_val[start_stage + 1];
187 b_param = ad714x->sensor_val[start_stage] +
188 ad714x->sensor_val[start_stage + 1];
189 } else if (highest_stage == end_stage) {
190 a_param = ad714x->sensor_val[end_stage] *
191 (end_stage - start_stage) +
192 ad714x->sensor_val[end_stage - 1] *
193 (end_stage - start_stage - 1);
194 b_param = ad714x->sensor_val[end_stage] +
195 ad714x->sensor_val[end_stage - 1];
196 } else {
197 a_param = ad714x->sensor_val[highest_stage] *
198 (highest_stage - start_stage) +
199 ad714x->sensor_val[highest_stage - 1] *
200 (highest_stage - start_stage - 1) +
201 ad714x->sensor_val[highest_stage + 1] *
202 (highest_stage - start_stage + 1);
203 b_param = ad714x->sensor_val[highest_stage] +
204 ad714x->sensor_val[highest_stage - 1] +
205 ad714x->sensor_val[highest_stage + 1];
206 }
207
208 return (max_coord / (end_stage - start_stage)) * a_param / b_param;
209}
210
211/*
212 * One button can connect to multi positive and negative of CDCs
213 * Multi-buttons can connect to same positive/negative of one CDC
214 */
215static void ad714x_button_state_machine(struct ad714x_chip *ad714x, int idx)
216{
217 struct ad714x_button_plat *hw = &ad714x->hw->button[idx];
218 struct ad714x_button_drv *sw = &ad714x->sw->button[idx];
219
220 switch (sw->state) {
221 case IDLE:
222 if (((ad714x->h_state & hw->h_mask) == hw->h_mask) &&
223 ((ad714x->l_state & hw->l_mask) == hw->l_mask)) {
224 dev_dbg(ad714x->dev, "button %d touched\n", idx);
225 input_report_key(sw->input, hw->keycode, 1);
226 input_sync(sw->input);
227 sw->state = ACTIVE;
228 }
229 break;
230
231 case ACTIVE:
232 if (((ad714x->h_state & hw->h_mask) != hw->h_mask) ||
233 ((ad714x->l_state & hw->l_mask) != hw->l_mask)) {
234 dev_dbg(ad714x->dev, "button %d released\n", idx);
235 input_report_key(sw->input, hw->keycode, 0);
236 input_sync(sw->input);
237 sw->state = IDLE;
238 }
239 break;
240
241 default:
242 break;
243 }
244}
245
246/*
247 * The response of a sensor is defined by the absolute number of codes
248 * between the current CDC value and the ambient value.
249 */
250static void ad714x_slider_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
251{
252 struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
253 int i;
254
255 ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
256 &ad714x->adc_reg[hw->start_stage],
257 hw->end_stage - hw->start_stage + 1);
258
259 for (i = hw->start_stage; i <= hw->end_stage; i++) {
260 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
261 &ad714x->amb_reg[i], 1);
262
263 ad714x->sensor_val[i] =
264 abs(ad714x->adc_reg[i] - ad714x->amb_reg[i]);
265 }
266}
267
268static void ad714x_slider_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
269{
270 struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
271 struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
272
273 sw->highest_stage = ad714x_cal_highest_stage(ad714x, hw->start_stage,
274 hw->end_stage);
275
276 dev_dbg(ad714x->dev, "slider %d highest_stage:%d\n", idx,
277 sw->highest_stage);
278}
279
280/*
281 * The formulae are very straight forward. It uses the sensor with the
282 * highest response and the 2 adjacent ones.
283 * When Sensor 0 has the highest response, only sensor 0 and sensor 1
284 * are used in the calculations. Similarly when the last sensor has the
285 * highest response, only the last sensor and the second last sensors
286 * are used in the calculations.
287 *
288 * For i= idx_of_peak_Sensor-1 to i= idx_of_peak_Sensor+1
289 * v += Sensor response(i)*i
290 * w += Sensor response(i)
291 * POS=(Number_of_Positions_Wanted/(Number_of_Sensors_Used-1)) *(v/w)
292 */
293static void ad714x_slider_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
294{
295 struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
296 struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
297
298 sw->abs_pos = ad714x_cal_abs_pos(ad714x, hw->start_stage, hw->end_stage,
299 sw->highest_stage, hw->max_coord);
300
301 dev_dbg(ad714x->dev, "slider %d absolute position:%d\n", idx,
302 sw->abs_pos);
303}
304
305/*
306 * To minimise the Impact of the noise on the algorithm, ADI developed a
307 * routine that filters the CDC results after they have been read by the
308 * host processor.
309 * The filter used is an Infinite Input Response(IIR) filter implemented
310 * in firmware and attenuates the noise on the CDC results after they've
311 * been read by the host processor.
312 * Filtered_CDC_result = (Filtered_CDC_result * (10 - Coefficient) +
313 * Latest_CDC_result * Coefficient)/10
314 */
315static void ad714x_slider_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
316{
317 struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
318
319 sw->flt_pos = (sw->flt_pos * (10 - 4) +
320 sw->abs_pos * 4)/10;
321
322 dev_dbg(ad714x->dev, "slider %d filter position:%d\n", idx,
323 sw->flt_pos);
324}
325
326static void ad714x_slider_use_com_int(struct ad714x_chip *ad714x, int idx)
327{
328 struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
329
330 ad714x_use_com_int(ad714x, hw->start_stage, hw->end_stage);
331}
332
333static void ad714x_slider_use_thr_int(struct ad714x_chip *ad714x, int idx)
334{
335 struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
336
337 ad714x_use_thr_int(ad714x, hw->start_stage, hw->end_stage);
338}
339
340static void ad714x_slider_state_machine(struct ad714x_chip *ad714x, int idx)
341{
342 struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
343 struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
344 unsigned short h_state, c_state;
345 unsigned short mask;
346
347 mask = ((1 << (hw->end_stage + 1)) - 1) - ((1 << hw->start_stage) - 1);
348
349 h_state = ad714x->h_state & mask;
350 c_state = ad714x->c_state & mask;
351
352 switch (sw->state) {
353 case IDLE:
354 if (h_state) {
355 sw->state = JITTER;
356 /* In End of Conversion interrupt mode, the AD714X
357 * continuously generates hardware interrupts.
358 */
359 ad714x_slider_use_com_int(ad714x, idx);
360 dev_dbg(ad714x->dev, "slider %d touched\n", idx);
361 }
362 break;
363
364 case JITTER:
365 if (c_state == mask) {
366 ad714x_slider_cal_sensor_val(ad714x, idx);
367 ad714x_slider_cal_highest_stage(ad714x, idx);
368 ad714x_slider_cal_abs_pos(ad714x, idx);
369 sw->flt_pos = sw->abs_pos;
370 sw->state = ACTIVE;
371 }
372 break;
373
374 case ACTIVE:
375 if (c_state == mask) {
376 if (h_state) {
377 ad714x_slider_cal_sensor_val(ad714x, idx);
378 ad714x_slider_cal_highest_stage(ad714x, idx);
379 ad714x_slider_cal_abs_pos(ad714x, idx);
380 ad714x_slider_cal_flt_pos(ad714x, idx);
381 input_report_abs(sw->input, ABS_X, sw->flt_pos);
382 input_report_key(sw->input, BTN_TOUCH, 1);
383 } else {
384 /* When the user lifts off the sensor, configure
385 * the AD714X back to threshold interrupt mode.
386 */
387 ad714x_slider_use_thr_int(ad714x, idx);
388 sw->state = IDLE;
389 input_report_key(sw->input, BTN_TOUCH, 0);
390 dev_dbg(ad714x->dev, "slider %d released\n",
391 idx);
392 }
393 input_sync(sw->input);
394 }
395 break;
396
397 default:
398 break;
399 }
400}
401
402/*
403 * When the scroll wheel is activated, we compute the absolute position based
404 * on the sensor values. To calculate the position, we first determine the
405 * sensor that has the greatest response among the 8 sensors that constitutes
406 * the scrollwheel. Then we determined the 2 sensors on either sides of the
407 * sensor with the highest response and we apply weights to these sensors.
408 */
409static void ad714x_wheel_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
410{
411 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
412 struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
413
414 sw->pre_highest_stage = sw->highest_stage;
415 sw->highest_stage = ad714x_cal_highest_stage(ad714x, hw->start_stage,
416 hw->end_stage);
417
418 dev_dbg(ad714x->dev, "wheel %d highest_stage:%d\n", idx,
419 sw->highest_stage);
420}
421
422static void ad714x_wheel_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
423{
424 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
425 int i;
426
427 ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
428 &ad714x->adc_reg[hw->start_stage],
429 hw->end_stage - hw->start_stage + 1);
430
431 for (i = hw->start_stage; i <= hw->end_stage; i++) {
432 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
433 &ad714x->amb_reg[i], 1);
434 if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
435 ad714x->sensor_val[i] =
436 ad714x->adc_reg[i] - ad714x->amb_reg[i];
437 else
438 ad714x->sensor_val[i] = 0;
439 }
440}
441
442/*
443 * When the scroll wheel is activated, we compute the absolute position based
444 * on the sensor values. To calculate the position, we first determine the
445 * sensor that has the greatest response among the sensors that constitutes
446 * the scrollwheel. Then we determined the sensors on either sides of the
447 * sensor with the highest response and we apply weights to these sensors. The
448 * result of this computation gives us the mean value.
449 */
450
451static void ad714x_wheel_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
452{
453 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
454 struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
455 int stage_num = hw->end_stage - hw->start_stage + 1;
456 int first_before, highest, first_after;
457 int a_param, b_param;
458
459 first_before = (sw->highest_stage + stage_num - 1) % stage_num;
460 highest = sw->highest_stage;
461 first_after = (sw->highest_stage + stage_num + 1) % stage_num;
462
463 a_param = ad714x->sensor_val[highest] *
464 (highest - hw->start_stage) +
465 ad714x->sensor_val[first_before] *
466 (highest - hw->start_stage - 1) +
467 ad714x->sensor_val[first_after] *
468 (highest - hw->start_stage + 1);
469 b_param = ad714x->sensor_val[highest] +
470 ad714x->sensor_val[first_before] +
471 ad714x->sensor_val[first_after];
472
473 sw->abs_pos = ((hw->max_coord / (hw->end_stage - hw->start_stage)) *
474 a_param) / b_param;
475
476 if (sw->abs_pos > hw->max_coord)
477 sw->abs_pos = hw->max_coord;
478 else if (sw->abs_pos < 0)
479 sw->abs_pos = 0;
480}
481
482static void ad714x_wheel_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
483{
484 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
485 struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
486 if (((sw->pre_highest_stage == hw->end_stage) &&
487 (sw->highest_stage == hw->start_stage)) ||
488 ((sw->pre_highest_stage == hw->start_stage) &&
489 (sw->highest_stage == hw->end_stage)))
490 sw->flt_pos = sw->abs_pos;
491 else
492 sw->flt_pos = ((sw->flt_pos * 30) + (sw->abs_pos * 71)) / 100;
493
494 if (sw->flt_pos > hw->max_coord)
495 sw->flt_pos = hw->max_coord;
496}
497
498static void ad714x_wheel_use_com_int(struct ad714x_chip *ad714x, int idx)
499{
500 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
501
502 ad714x_use_com_int(ad714x, hw->start_stage, hw->end_stage);
503}
504
505static void ad714x_wheel_use_thr_int(struct ad714x_chip *ad714x, int idx)
506{
507 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
508
509 ad714x_use_thr_int(ad714x, hw->start_stage, hw->end_stage);
510}
511
512static void ad714x_wheel_state_machine(struct ad714x_chip *ad714x, int idx)
513{
514 struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
515 struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
516 unsigned short h_state, c_state;
517 unsigned short mask;
518
519 mask = ((1 << (hw->end_stage + 1)) - 1) - ((1 << hw->start_stage) - 1);
520
521 h_state = ad714x->h_state & mask;
522 c_state = ad714x->c_state & mask;
523
524 switch (sw->state) {
525 case IDLE:
526 if (h_state) {
527 sw->state = JITTER;
528 /* In End of Conversion interrupt mode, the AD714X
529 * continuously generates hardware interrupts.
530 */
531 ad714x_wheel_use_com_int(ad714x, idx);
532 dev_dbg(ad714x->dev, "wheel %d touched\n", idx);
533 }
534 break;
535
536 case JITTER:
537 if (c_state == mask) {
538 ad714x_wheel_cal_sensor_val(ad714x, idx);
539 ad714x_wheel_cal_highest_stage(ad714x, idx);
540 ad714x_wheel_cal_abs_pos(ad714x, idx);
541 sw->flt_pos = sw->abs_pos;
542 sw->state = ACTIVE;
543 }
544 break;
545
546 case ACTIVE:
547 if (c_state == mask) {
548 if (h_state) {
549 ad714x_wheel_cal_sensor_val(ad714x, idx);
550 ad714x_wheel_cal_highest_stage(ad714x, idx);
551 ad714x_wheel_cal_abs_pos(ad714x, idx);
552 ad714x_wheel_cal_flt_pos(ad714x, idx);
553 input_report_abs(sw->input, ABS_WHEEL,
554 sw->flt_pos);
555 input_report_key(sw->input, BTN_TOUCH, 1);
556 } else {
557 /* When the user lifts off the sensor, configure
558 * the AD714X back to threshold interrupt mode.
559 */
560 ad714x_wheel_use_thr_int(ad714x, idx);
561 sw->state = IDLE;
562 input_report_key(sw->input, BTN_TOUCH, 0);
563
564 dev_dbg(ad714x->dev, "wheel %d released\n",
565 idx);
566 }
567 input_sync(sw->input);
568 }
569 break;
570
571 default:
572 break;
573 }
574}
575
576static void touchpad_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
577{
578 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
579 int i;
580
581 ad714x->read(ad714x, CDC_RESULT_S0 + hw->x_start_stage,
582 &ad714x->adc_reg[hw->x_start_stage],
583 hw->x_end_stage - hw->x_start_stage + 1);
584
585 for (i = hw->x_start_stage; i <= hw->x_end_stage; i++) {
586 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
587 &ad714x->amb_reg[i], 1);
588 if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
589 ad714x->sensor_val[i] =
590 ad714x->adc_reg[i] - ad714x->amb_reg[i];
591 else
592 ad714x->sensor_val[i] = 0;
593 }
594}
595
596static void touchpad_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
597{
598 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
599 struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
600
601 sw->x_highest_stage = ad714x_cal_highest_stage(ad714x,
602 hw->x_start_stage, hw->x_end_stage);
603 sw->y_highest_stage = ad714x_cal_highest_stage(ad714x,
604 hw->y_start_stage, hw->y_end_stage);
605
606 dev_dbg(ad714x->dev,
607 "touchpad %d x_highest_stage:%d, y_highest_stage:%d\n",
608 idx, sw->x_highest_stage, sw->y_highest_stage);
609}
610
611/*
612 * If 2 fingers are touching the sensor then 2 peaks can be observed in the
613 * distribution.
614 * The arithmetic doesn't support to get absolute coordinates for multi-touch
615 * yet.
616 */
617static int touchpad_check_second_peak(struct ad714x_chip *ad714x, int idx)
618{
619 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
620 struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
621 int i;
622
623 for (i = hw->x_start_stage; i < sw->x_highest_stage; i++) {
624 if ((ad714x->sensor_val[i] - ad714x->sensor_val[i + 1])
625 > (ad714x->sensor_val[i + 1] / 10))
626 return 1;
627 }
628
629 for (i = sw->x_highest_stage; i < hw->x_end_stage; i++) {
630 if ((ad714x->sensor_val[i + 1] - ad714x->sensor_val[i])
631 > (ad714x->sensor_val[i] / 10))
632 return 1;
633 }
634
635 for (i = hw->y_start_stage; i < sw->y_highest_stage; i++) {
636 if ((ad714x->sensor_val[i] - ad714x->sensor_val[i + 1])
637 > (ad714x->sensor_val[i + 1] / 10))
638 return 1;
639 }
640
641 for (i = sw->y_highest_stage; i < hw->y_end_stage; i++) {
642 if ((ad714x->sensor_val[i + 1] - ad714x->sensor_val[i])
643 > (ad714x->sensor_val[i] / 10))
644 return 1;
645 }
646
647 return 0;
648}
649
650/*
651 * If only one finger is used to activate the touch pad then only 1 peak will be
652 * registered in the distribution. This peak and the 2 adjacent sensors will be
653 * used in the calculation of the absolute position. This will prevent hand
654 * shadows to affect the absolute position calculation.
655 */
656static void touchpad_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
657{
658 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
659 struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
660
661 sw->x_abs_pos = ad714x_cal_abs_pos(ad714x, hw->x_start_stage,
662 hw->x_end_stage, sw->x_highest_stage, hw->x_max_coord);
663 sw->y_abs_pos = ad714x_cal_abs_pos(ad714x, hw->y_start_stage,
664 hw->y_end_stage, sw->y_highest_stage, hw->y_max_coord);
665
666 dev_dbg(ad714x->dev, "touchpad %d absolute position:(%d, %d)\n", idx,
667 sw->x_abs_pos, sw->y_abs_pos);
668}
669
670static void touchpad_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
671{
672 struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
673
674 sw->x_flt_pos = (sw->x_flt_pos * (10 - 4) +
675 sw->x_abs_pos * 4)/10;
676 sw->y_flt_pos = (sw->y_flt_pos * (10 - 4) +
677 sw->y_abs_pos * 4)/10;
678
679 dev_dbg(ad714x->dev, "touchpad %d filter position:(%d, %d)\n",
680 idx, sw->x_flt_pos, sw->y_flt_pos);
681}
682
683/*
684 * To prevent distortion from showing in the absolute position, it is
685 * necessary to detect the end points. When endpoints are detected, the
686 * driver stops updating the status variables with absolute positions.
687 * End points are detected on the 4 edges of the touchpad sensor. The
688 * method to detect them is the same for all 4.
689 * To detect the end points, the firmware computes the difference in
690 * percent between the sensor on the edge and the adjacent one. The
691 * difference is calculated in percent in order to make the end point
692 * detection independent of the pressure.
693 */
694
695#define LEFT_END_POINT_DETECTION_LEVEL 550
696#define RIGHT_END_POINT_DETECTION_LEVEL 750
697#define LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL 850
698#define TOP_END_POINT_DETECTION_LEVEL 550
699#define BOTTOM_END_POINT_DETECTION_LEVEL 950
700#define TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL 700
701static int touchpad_check_endpoint(struct ad714x_chip *ad714x, int idx)
702{
703 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
704 struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
705 int percent_sensor_diff;
706
707 /* left endpoint detect */
708 percent_sensor_diff = (ad714x->sensor_val[hw->x_start_stage] -
709 ad714x->sensor_val[hw->x_start_stage + 1]) * 100 /
710 ad714x->sensor_val[hw->x_start_stage + 1];
711 if (!sw->left_ep) {
712 if (percent_sensor_diff >= LEFT_END_POINT_DETECTION_LEVEL) {
713 sw->left_ep = 1;
714 sw->left_ep_val =
715 ad714x->sensor_val[hw->x_start_stage + 1];
716 }
717 } else {
718 if ((percent_sensor_diff < LEFT_END_POINT_DETECTION_LEVEL) &&
719 (ad714x->sensor_val[hw->x_start_stage + 1] >
720 LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL + sw->left_ep_val))
721 sw->left_ep = 0;
722 }
723
724 /* right endpoint detect */
725 percent_sensor_diff = (ad714x->sensor_val[hw->x_end_stage] -
726 ad714x->sensor_val[hw->x_end_stage - 1]) * 100 /
727 ad714x->sensor_val[hw->x_end_stage - 1];
728 if (!sw->right_ep) {
729 if (percent_sensor_diff >= RIGHT_END_POINT_DETECTION_LEVEL) {
730 sw->right_ep = 1;
731 sw->right_ep_val =
732 ad714x->sensor_val[hw->x_end_stage - 1];
733 }
734 } else {
735 if ((percent_sensor_diff < RIGHT_END_POINT_DETECTION_LEVEL) &&
736 (ad714x->sensor_val[hw->x_end_stage - 1] >
737 LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL + sw->right_ep_val))
738 sw->right_ep = 0;
739 }
740
741 /* top endpoint detect */
742 percent_sensor_diff = (ad714x->sensor_val[hw->y_start_stage] -
743 ad714x->sensor_val[hw->y_start_stage + 1]) * 100 /
744 ad714x->sensor_val[hw->y_start_stage + 1];
745 if (!sw->top_ep) {
746 if (percent_sensor_diff >= TOP_END_POINT_DETECTION_LEVEL) {
747 sw->top_ep = 1;
748 sw->top_ep_val =
749 ad714x->sensor_val[hw->y_start_stage + 1];
750 }
751 } else {
752 if ((percent_sensor_diff < TOP_END_POINT_DETECTION_LEVEL) &&
753 (ad714x->sensor_val[hw->y_start_stage + 1] >
754 TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL + sw->top_ep_val))
755 sw->top_ep = 0;
756 }
757
758 /* bottom endpoint detect */
759 percent_sensor_diff = (ad714x->sensor_val[hw->y_end_stage] -
760 ad714x->sensor_val[hw->y_end_stage - 1]) * 100 /
761 ad714x->sensor_val[hw->y_end_stage - 1];
762 if (!sw->bottom_ep) {
763 if (percent_sensor_diff >= BOTTOM_END_POINT_DETECTION_LEVEL) {
764 sw->bottom_ep = 1;
765 sw->bottom_ep_val =
766 ad714x->sensor_val[hw->y_end_stage - 1];
767 }
768 } else {
769 if ((percent_sensor_diff < BOTTOM_END_POINT_DETECTION_LEVEL) &&
770 (ad714x->sensor_val[hw->y_end_stage - 1] >
771 TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL + sw->bottom_ep_val))
772 sw->bottom_ep = 0;
773 }
774
775 return sw->left_ep || sw->right_ep || sw->top_ep || sw->bottom_ep;
776}
777
778static void touchpad_use_com_int(struct ad714x_chip *ad714x, int idx)
779{
780 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
781
782 ad714x_use_com_int(ad714x, hw->x_start_stage, hw->x_end_stage);
783}
784
785static void touchpad_use_thr_int(struct ad714x_chip *ad714x, int idx)
786{
787 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
788
789 ad714x_use_thr_int(ad714x, hw->x_start_stage, hw->x_end_stage);
790 ad714x_use_thr_int(ad714x, hw->y_start_stage, hw->y_end_stage);
791}
792
793static void ad714x_touchpad_state_machine(struct ad714x_chip *ad714x, int idx)
794{
795 struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
796 struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
797 unsigned short h_state, c_state;
798 unsigned short mask;
799
800 mask = (((1 << (hw->x_end_stage + 1)) - 1) -
801 ((1 << hw->x_start_stage) - 1)) +
802 (((1 << (hw->y_end_stage + 1)) - 1) -
803 ((1 << hw->y_start_stage) - 1));
804
805 h_state = ad714x->h_state & mask;
806 c_state = ad714x->c_state & mask;
807
808 switch (sw->state) {
809 case IDLE:
810 if (h_state) {
811 sw->state = JITTER;
812 /* In End of Conversion interrupt mode, the AD714X
813 * continuously generates hardware interrupts.
814 */
815 touchpad_use_com_int(ad714x, idx);
816 dev_dbg(ad714x->dev, "touchpad %d touched\n", idx);
817 }
818 break;
819
820 case JITTER:
821 if (c_state == mask) {
822 touchpad_cal_sensor_val(ad714x, idx);
823 touchpad_cal_highest_stage(ad714x, idx);
824 if ((!touchpad_check_second_peak(ad714x, idx)) &&
825 (!touchpad_check_endpoint(ad714x, idx))) {
826 dev_dbg(ad714x->dev,
827 "touchpad%d, 2 fingers or endpoint\n",
828 idx);
829 touchpad_cal_abs_pos(ad714x, idx);
830 sw->x_flt_pos = sw->x_abs_pos;
831 sw->y_flt_pos = sw->y_abs_pos;
832 sw->state = ACTIVE;
833 }
834 }
835 break;
836
837 case ACTIVE:
838 if (c_state == mask) {
839 if (h_state) {
840 touchpad_cal_sensor_val(ad714x, idx);
841 touchpad_cal_highest_stage(ad714x, idx);
842 if ((!touchpad_check_second_peak(ad714x, idx))
843 && (!touchpad_check_endpoint(ad714x, idx))) {
844 touchpad_cal_abs_pos(ad714x, idx);
845 touchpad_cal_flt_pos(ad714x, idx);
846 input_report_abs(sw->input, ABS_X,
847 sw->x_flt_pos);
848 input_report_abs(sw->input, ABS_Y,
849 sw->y_flt_pos);
850 input_report_key(sw->input, BTN_TOUCH,
851 1);
852 }
853 } else {
854 /* When the user lifts off the sensor, configure
855 * the AD714X back to threshold interrupt mode.
856 */
857 touchpad_use_thr_int(ad714x, idx);
858 sw->state = IDLE;
859 input_report_key(sw->input, BTN_TOUCH, 0);
860 dev_dbg(ad714x->dev, "touchpad %d released\n",
861 idx);
862 }
863 input_sync(sw->input);
864 }
865 break;
866
867 default:
868 break;
869 }
870}
871
872static int ad714x_hw_detect(struct ad714x_chip *ad714x)
873{
874 unsigned short data;
875
876 ad714x->read(ad714x, AD714X_PARTID_REG, &data, 1);
877 switch (data & 0xFFF0) {
878 case AD7142_PARTID:
879 ad714x->product = 0x7142;
880 ad714x->version = data & 0xF;
881 dev_info(ad714x->dev, "found AD7142 captouch, rev:%d\n",
882 ad714x->version);
883 return 0;
884
885 case AD7143_PARTID:
886 ad714x->product = 0x7143;
887 ad714x->version = data & 0xF;
888 dev_info(ad714x->dev, "found AD7143 captouch, rev:%d\n",
889 ad714x->version);
890 return 0;
891
892 case AD7147_PARTID:
893 ad714x->product = 0x7147;
894 ad714x->version = data & 0xF;
895 dev_info(ad714x->dev, "found AD7147(A) captouch, rev:%d\n",
896 ad714x->version);
897 return 0;
898
899 case AD7148_PARTID:
900 ad714x->product = 0x7148;
901 ad714x->version = data & 0xF;
902 dev_info(ad714x->dev, "found AD7148 captouch, rev:%d\n",
903 ad714x->version);
904 return 0;
905
906 default:
907 dev_err(ad714x->dev,
908 "fail to detect AD714X captouch, read ID is %04x\n",
909 data);
910 return -ENODEV;
911 }
912}
913
914static void ad714x_hw_init(struct ad714x_chip *ad714x)
915{
916 int i, j;
917 unsigned short reg_base;
918 unsigned short data;
919
920 /* configuration CDC and interrupts */
921
922 for (i = 0; i < STAGE_NUM; i++) {
923 reg_base = AD714X_STAGECFG_REG + i * STAGE_CFGREG_NUM;
924 for (j = 0; j < STAGE_CFGREG_NUM; j++)
925 ad714x->write(ad714x, reg_base + j,
926 ad714x->hw->stage_cfg_reg[i][j]);
927 }
928
929 for (i = 0; i < SYS_CFGREG_NUM; i++)
930 ad714x->write(ad714x, AD714X_SYSCFG_REG + i,
931 ad714x->hw->sys_cfg_reg[i]);
932 for (i = 0; i < SYS_CFGREG_NUM; i++)
933 ad714x->read(ad714x, AD714X_SYSCFG_REG + i, &data, 1);
934
935 ad714x->write(ad714x, AD714X_STG_CAL_EN_REG, 0xFFF);
936
937 /* clear all interrupts */
938 ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
939}
940
941static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
942{
943 struct ad714x_chip *ad714x = data;
944 int i;
945
946 mutex_lock(&ad714x->mutex);
947
948 ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
949
950 for (i = 0; i < ad714x->hw->button_num; i++)
951 ad714x_button_state_machine(ad714x, i);
952 for (i = 0; i < ad714x->hw->slider_num; i++)
953 ad714x_slider_state_machine(ad714x, i);
954 for (i = 0; i < ad714x->hw->wheel_num; i++)
955 ad714x_wheel_state_machine(ad714x, i);
956 for (i = 0; i < ad714x->hw->touchpad_num; i++)
957 ad714x_touchpad_state_machine(ad714x, i);
958
959 mutex_unlock(&ad714x->mutex);
960
961 return IRQ_HANDLED;
962}
963
964#define MAX_DEVICE_NUM 8
965struct ad714x_chip *ad714x_probe(struct device *dev, u16 bus_type, int irq,
966 ad714x_read_t read, ad714x_write_t write)
967{
968 int i, alloc_idx;
969 int error;
970 struct input_dev *input[MAX_DEVICE_NUM];
971
972 struct ad714x_platform_data *plat_data = dev->platform_data;
973 struct ad714x_chip *ad714x;
974 void *drv_mem;
975 unsigned long irqflags;
976
977 struct ad714x_button_drv *bt_drv;
978 struct ad714x_slider_drv *sd_drv;
979 struct ad714x_wheel_drv *wl_drv;
980 struct ad714x_touchpad_drv *tp_drv;
981
982
983 if (irq <= 0) {
984 dev_err(dev, "IRQ not configured!\n");
985 error = -EINVAL;
986 goto err_out;
987 }
988
989 if (dev->platform_data == NULL) {
990 dev_err(dev, "platform data for ad714x doesn't exist\n");
991 error = -EINVAL;
992 goto err_out;
993 }
994
995 ad714x = kzalloc(sizeof(*ad714x) + sizeof(*ad714x->sw) +
996 sizeof(*sd_drv) * plat_data->slider_num +
997 sizeof(*wl_drv) * plat_data->wheel_num +
998 sizeof(*tp_drv) * plat_data->touchpad_num +
999 sizeof(*bt_drv) * plat_data->button_num, GFP_KERNEL);
1000 if (!ad714x) {
1001 error = -ENOMEM;
1002 goto err_out;
1003 }
1004
1005 ad714x->hw = plat_data;
1006
1007 drv_mem = ad714x + 1;
1008 ad714x->sw = drv_mem;
1009 drv_mem += sizeof(*ad714x->sw);
1010 ad714x->sw->slider = sd_drv = drv_mem;
1011 drv_mem += sizeof(*sd_drv) * ad714x->hw->slider_num;
1012 ad714x->sw->wheel = wl_drv = drv_mem;
1013 drv_mem += sizeof(*wl_drv) * ad714x->hw->wheel_num;
1014 ad714x->sw->touchpad = tp_drv = drv_mem;
1015 drv_mem += sizeof(*tp_drv) * ad714x->hw->touchpad_num;
1016 ad714x->sw->button = bt_drv = drv_mem;
1017 drv_mem += sizeof(*bt_drv) * ad714x->hw->button_num;
1018
1019 ad714x->read = read;
1020 ad714x->write = write;
1021 ad714x->irq = irq;
1022 ad714x->dev = dev;
1023
1024 error = ad714x_hw_detect(ad714x);
1025 if (error)
1026 goto err_free_mem;
1027
1028 /* initialize and request sw/hw resources */
1029
1030 ad714x_hw_init(ad714x);
1031 mutex_init(&ad714x->mutex);
1032
1033 /*
1034 * Allocate and register AD714X input device
1035 */
1036 alloc_idx = 0;
1037
1038 /* a slider uses one input_dev instance */
1039 if (ad714x->hw->slider_num > 0) {
1040 struct ad714x_slider_plat *sd_plat = ad714x->hw->slider;
1041
1042 for (i = 0; i < ad714x->hw->slider_num; i++) {
1043 sd_drv[i].input = input[alloc_idx] = input_allocate_device();
1044 if (!input[alloc_idx]) {
1045 error = -ENOMEM;
1046 goto err_free_dev;
1047 }
1048
1049 __set_bit(EV_ABS, input[alloc_idx]->evbit);
1050 __set_bit(EV_KEY, input[alloc_idx]->evbit);
1051 __set_bit(ABS_X, input[alloc_idx]->absbit);
1052 __set_bit(BTN_TOUCH, input[alloc_idx]->keybit);
1053 input_set_abs_params(input[alloc_idx],
1054 ABS_X, 0, sd_plat->max_coord, 0, 0);
1055
1056 input[alloc_idx]->id.bustype = bus_type;
1057 input[alloc_idx]->id.product = ad714x->product;
1058 input[alloc_idx]->id.version = ad714x->version;
1059 input[alloc_idx]->name = "ad714x_captouch_slider";
1060 input[alloc_idx]->dev.parent = dev;
1061
1062 error = input_register_device(input[alloc_idx]);
1063 if (error)
1064 goto err_free_dev;
1065
1066 alloc_idx++;
1067 }
1068 }
1069
1070 /* a wheel uses one input_dev instance */
1071 if (ad714x->hw->wheel_num > 0) {
1072 struct ad714x_wheel_plat *wl_plat = ad714x->hw->wheel;
1073
1074 for (i = 0; i < ad714x->hw->wheel_num; i++) {
1075 wl_drv[i].input = input[alloc_idx] = input_allocate_device();
1076 if (!input[alloc_idx]) {
1077 error = -ENOMEM;
1078 goto err_free_dev;
1079 }
1080
1081 __set_bit(EV_KEY, input[alloc_idx]->evbit);
1082 __set_bit(EV_ABS, input[alloc_idx]->evbit);
1083 __set_bit(ABS_WHEEL, input[alloc_idx]->absbit);
1084 __set_bit(BTN_TOUCH, input[alloc_idx]->keybit);
1085 input_set_abs_params(input[alloc_idx],
1086 ABS_WHEEL, 0, wl_plat->max_coord, 0, 0);
1087
1088 input[alloc_idx]->id.bustype = bus_type;
1089 input[alloc_idx]->id.product = ad714x->product;
1090 input[alloc_idx]->id.version = ad714x->version;
1091 input[alloc_idx]->name = "ad714x_captouch_wheel";
1092 input[alloc_idx]->dev.parent = dev;
1093
1094 error = input_register_device(input[alloc_idx]);
1095 if (error)
1096 goto err_free_dev;
1097
1098 alloc_idx++;
1099 }
1100 }
1101
1102 /* a touchpad uses one input_dev instance */
1103 if (ad714x->hw->touchpad_num > 0) {
1104 struct ad714x_touchpad_plat *tp_plat = ad714x->hw->touchpad;
1105
1106 for (i = 0; i < ad714x->hw->touchpad_num; i++) {
1107 tp_drv[i].input = input[alloc_idx] = input_allocate_device();
1108 if (!input[alloc_idx]) {
1109 error = -ENOMEM;
1110 goto err_free_dev;
1111 }
1112
1113 __set_bit(EV_ABS, input[alloc_idx]->evbit);
1114 __set_bit(EV_KEY, input[alloc_idx]->evbit);
1115 __set_bit(ABS_X, input[alloc_idx]->absbit);
1116 __set_bit(ABS_Y, input[alloc_idx]->absbit);
1117 __set_bit(BTN_TOUCH, input[alloc_idx]->keybit);
1118 input_set_abs_params(input[alloc_idx],
1119 ABS_X, 0, tp_plat->x_max_coord, 0, 0);
1120 input_set_abs_params(input[alloc_idx],
1121 ABS_Y, 0, tp_plat->y_max_coord, 0, 0);
1122
1123 input[alloc_idx]->id.bustype = bus_type;
1124 input[alloc_idx]->id.product = ad714x->product;
1125 input[alloc_idx]->id.version = ad714x->version;
1126 input[alloc_idx]->name = "ad714x_captouch_pad";
1127 input[alloc_idx]->dev.parent = dev;
1128
1129 error = input_register_device(input[alloc_idx]);
1130 if (error)
1131 goto err_free_dev;
1132
1133 alloc_idx++;
1134 }
1135 }
1136
1137 /* all buttons use one input node */
1138 if (ad714x->hw->button_num > 0) {
1139 struct ad714x_button_plat *bt_plat = ad714x->hw->button;
1140
1141 input[alloc_idx] = input_allocate_device();
1142 if (!input[alloc_idx]) {
1143 error = -ENOMEM;
1144 goto err_free_dev;
1145 }
1146
1147 __set_bit(EV_KEY, input[alloc_idx]->evbit);
1148 for (i = 0; i < ad714x->hw->button_num; i++) {
1149 bt_drv[i].input = input[alloc_idx];
1150 __set_bit(bt_plat[i].keycode, input[alloc_idx]->keybit);
1151 }
1152
1153 input[alloc_idx]->id.bustype = bus_type;
1154 input[alloc_idx]->id.product = ad714x->product;
1155 input[alloc_idx]->id.version = ad714x->version;
1156 input[alloc_idx]->name = "ad714x_captouch_button";
1157 input[alloc_idx]->dev.parent = dev;
1158
1159 error = input_register_device(input[alloc_idx]);
1160 if (error)
1161 goto err_free_dev;
1162
1163 alloc_idx++;
1164 }
1165
1166 irqflags = plat_data->irqflags ?: IRQF_TRIGGER_FALLING;
1167 irqflags |= IRQF_ONESHOT;
1168
1169 error = request_threaded_irq(ad714x->irq, NULL, ad714x_interrupt_thread,
1170 irqflags, "ad714x_captouch", ad714x);
1171 if (error) {
1172 dev_err(dev, "can't allocate irq %d\n", ad714x->irq);
1173 goto err_unreg_dev;
1174 }
1175
1176 return ad714x;
1177
1178 err_free_dev:
1179 dev_err(dev, "failed to setup AD714x input device %i\n", alloc_idx);
1180 input_free_device(input[alloc_idx]);
1181 err_unreg_dev:
1182 while (--alloc_idx >= 0)
1183 input_unregister_device(input[alloc_idx]);
1184 err_free_mem:
1185 kfree(ad714x);
1186 err_out:
1187 return ERR_PTR(error);
1188}
1189EXPORT_SYMBOL(ad714x_probe);
1190
1191void ad714x_remove(struct ad714x_chip *ad714x)
1192{
1193 struct ad714x_platform_data *hw = ad714x->hw;
1194 struct ad714x_driver_data *sw = ad714x->sw;
1195 int i;
1196
1197 free_irq(ad714x->irq, ad714x);
1198
1199 /* unregister and free all input devices */
1200
1201 for (i = 0; i < hw->slider_num; i++)
1202 input_unregister_device(sw->slider[i].input);
1203
1204 for (i = 0; i < hw->wheel_num; i++)
1205 input_unregister_device(sw->wheel[i].input);
1206
1207 for (i = 0; i < hw->touchpad_num; i++)
1208 input_unregister_device(sw->touchpad[i].input);
1209
1210 if (hw->button_num)
1211 input_unregister_device(sw->button[0].input);
1212
1213 kfree(ad714x);
1214}
1215EXPORT_SYMBOL(ad714x_remove);
1216
1217#ifdef CONFIG_PM
1218int ad714x_disable(struct ad714x_chip *ad714x)
1219{
1220 unsigned short data;
1221
1222 dev_dbg(ad714x->dev, "%s enter\n", __func__);
1223
1224 mutex_lock(&ad714x->mutex);
1225
1226 data = ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL] | 0x3;
1227 ad714x->write(ad714x, AD714X_PWR_CTRL, data);
1228
1229 mutex_unlock(&ad714x->mutex);
1230
1231 return 0;
1232}
1233EXPORT_SYMBOL(ad714x_disable);
1234
1235int ad714x_enable(struct ad714x_chip *ad714x)
1236{
1237 dev_dbg(ad714x->dev, "%s enter\n", __func__);
1238
1239 mutex_lock(&ad714x->mutex);
1240
1241 /* resume to non-shutdown mode */
1242
1243 ad714x->write(ad714x, AD714X_PWR_CTRL,
1244 ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL]);
1245
1246 /* make sure the interrupt output line is not low level after resume,
1247 * otherwise we will get no chance to enter falling-edge irq again
1248 */
1249
1250 ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
1251
1252 mutex_unlock(&ad714x->mutex);
1253
1254 return 0;
1255}
1256EXPORT_SYMBOL(ad714x_enable);
1257#endif
1258
1259MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor Driver");
1260MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
1261MODULE_LICENSE("GPL");