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20#include <linux/types.h>
21#include <linux/hwmon.h>
22#include <linux/err.h>
23#include <linux/sched.h>
24#include <linux/delay.h>
25#include <linux/input.h>
26#include <linux/interrupt.h>
27#include <linux/slab.h>
28#include <linux/pm.h>
29#include <linux/of.h>
30#include <linux/of_gpio.h>
31#include <linux/of_device.h>
32#include <linux/gpio.h>
33#include <linux/spi/spi.h>
34#include <linux/spi/ads7846.h>
35#include <linux/regulator/consumer.h>
36#include <linux/module.h>
37#include <asm/irq.h>
38
39
40
41
42
43
44
45
46
47
48
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51
52
53
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56
57
58
59
60
61#define TS_POLL_DELAY 1
62#define TS_POLL_PERIOD 5
63
64
65#define SAMPLE_BITS (8 + 16 + 2 )
66
67struct ts_event {
68
69
70
71
72
73
74 u16 x;
75 u16 y;
76 u16 z1, z2;
77 bool ignore;
78 u8 x_buf[3];
79 u8 y_buf[3];
80};
81
82
83
84
85
86
87struct ads7846_packet {
88 u8 read_x, read_y, read_z1, read_z2, pwrdown;
89 u16 dummy;
90 struct ts_event tc;
91
92 u8 read_x_cmd[3], read_y_cmd[3], pwrdown_cmd[3];
93};
94
95struct ads7846 {
96 struct input_dev *input;
97 char phys[32];
98 char name[32];
99
100 struct spi_device *spi;
101 struct regulator *reg;
102
103#if IS_ENABLED(CONFIG_HWMON)
104 struct device *hwmon;
105#endif
106
107 u16 model;
108 u16 vref_mv;
109 u16 vref_delay_usecs;
110 u16 x_plate_ohms;
111 u16 pressure_max;
112
113 bool swap_xy;
114 bool use_internal;
115
116 struct ads7846_packet *packet;
117
118 struct spi_transfer xfer[18];
119 struct spi_message msg[5];
120 int msg_count;
121 wait_queue_head_t wait;
122
123 bool pendown;
124
125 int read_cnt;
126 int read_rep;
127 int last_read;
128
129 u16 debounce_max;
130 u16 debounce_tol;
131 u16 debounce_rep;
132
133 u16 penirq_recheck_delay_usecs;
134
135 struct mutex lock;
136 bool stopped;
137 bool disabled;
138 bool suspended;
139
140 int (*filter)(void *data, int data_idx, int *val);
141 void *filter_data;
142 void (*filter_cleanup)(void *data);
143 int (*get_pendown_state)(void);
144 int gpio_pendown;
145
146 void (*wait_for_sync)(void);
147};
148
149
150#if 0
151#define CS_CHANGE(xfer) ((xfer).cs_change = 1)
152#else
153#define CS_CHANGE(xfer) ((xfer).cs_change = 0)
154#endif
155
156
157
158
159
160
161#define ADS_START (1 << 7)
162#define ADS_A2A1A0_d_y (1 << 4)
163#define ADS_A2A1A0_d_z1 (3 << 4)
164#define ADS_A2A1A0_d_z2 (4 << 4)
165#define ADS_A2A1A0_d_x (5 << 4)
166#define ADS_A2A1A0_temp0 (0 << 4)
167#define ADS_A2A1A0_vbatt (2 << 4)
168#define ADS_A2A1A0_vaux (6 << 4)
169#define ADS_A2A1A0_temp1 (7 << 4)
170#define ADS_8_BIT (1 << 3)
171#define ADS_12_BIT (0 << 3)
172#define ADS_SER (1 << 2)
173#define ADS_DFR (0 << 2)
174#define ADS_PD10_PDOWN (0 << 0)
175#define ADS_PD10_ADC_ON (1 << 0)
176#define ADS_PD10_REF_ON (2 << 0)
177#define ADS_PD10_ALL_ON (3 << 0)
178
179#define MAX_12BIT ((1<<12)-1)
180
181
182#define READ_12BIT_DFR(x, adc, vref) (ADS_START | ADS_A2A1A0_d_ ## x \
183 | ADS_12_BIT | ADS_DFR | \
184 (adc ? ADS_PD10_ADC_ON : 0) | (vref ? ADS_PD10_REF_ON : 0))
185
186#define READ_Y(vref) (READ_12BIT_DFR(y, 1, vref))
187#define READ_Z1(vref) (READ_12BIT_DFR(z1, 1, vref))
188#define READ_Z2(vref) (READ_12BIT_DFR(z2, 1, vref))
189
190#define READ_X(vref) (READ_12BIT_DFR(x, 1, vref))
191#define PWRDOWN (READ_12BIT_DFR(y, 0, 0))
192
193
194
195
196#define READ_12BIT_SER(x) (ADS_START | ADS_A2A1A0_ ## x \
197 | ADS_12_BIT | ADS_SER)
198
199#define REF_ON (READ_12BIT_DFR(x, 1, 1))
200#define REF_OFF (READ_12BIT_DFR(y, 0, 0))
201
202
203static void ads7846_stop(struct ads7846 *ts)
204{
205 if (!ts->disabled && !ts->suspended) {
206
207 ts->stopped = true;
208 mb();
209 wake_up(&ts->wait);
210 disable_irq(ts->spi->irq);
211 }
212}
213
214
215static void ads7846_restart(struct ads7846 *ts)
216{
217 if (!ts->disabled && !ts->suspended) {
218
219 ts->stopped = false;
220 mb();
221 enable_irq(ts->spi->irq);
222 }
223}
224
225
226static void __ads7846_disable(struct ads7846 *ts)
227{
228 ads7846_stop(ts);
229 regulator_disable(ts->reg);
230
231
232
233
234
235}
236
237
238static void __ads7846_enable(struct ads7846 *ts)
239{
240 int error;
241
242 error = regulator_enable(ts->reg);
243 if (error != 0)
244 dev_err(&ts->spi->dev, "Failed to enable supply: %d\n", error);
245
246 ads7846_restart(ts);
247}
248
249static void ads7846_disable(struct ads7846 *ts)
250{
251 mutex_lock(&ts->lock);
252
253 if (!ts->disabled) {
254
255 if (!ts->suspended)
256 __ads7846_disable(ts);
257
258 ts->disabled = true;
259 }
260
261 mutex_unlock(&ts->lock);
262}
263
264static void ads7846_enable(struct ads7846 *ts)
265{
266 mutex_lock(&ts->lock);
267
268 if (ts->disabled) {
269
270 ts->disabled = false;
271
272 if (!ts->suspended)
273 __ads7846_enable(ts);
274 }
275
276 mutex_unlock(&ts->lock);
277}
278
279
280
281
282
283
284
285
286
287struct ser_req {
288 u8 ref_on;
289 u8 command;
290 u8 ref_off;
291 u16 scratch;
292 struct spi_message msg;
293 struct spi_transfer xfer[6];
294
295
296
297
298 __be16 sample ____cacheline_aligned;
299};
300
301struct ads7845_ser_req {
302 u8 command[3];
303 struct spi_message msg;
304 struct spi_transfer xfer[2];
305
306
307
308
309 u8 sample[3] ____cacheline_aligned;
310};
311
312static int ads7846_read12_ser(struct device *dev, unsigned command)
313{
314 struct spi_device *spi = to_spi_device(dev);
315 struct ads7846 *ts = dev_get_drvdata(dev);
316 struct ser_req *req;
317 int status;
318
319 req = kzalloc(sizeof *req, GFP_KERNEL);
320 if (!req)
321 return -ENOMEM;
322
323 spi_message_init(&req->msg);
324
325
326 if (ts->use_internal) {
327 req->ref_on = REF_ON;
328 req->xfer[0].tx_buf = &req->ref_on;
329 req->xfer[0].len = 1;
330 spi_message_add_tail(&req->xfer[0], &req->msg);
331
332 req->xfer[1].rx_buf = &req->scratch;
333 req->xfer[1].len = 2;
334
335
336 req->xfer[1].delay_usecs = ts->vref_delay_usecs;
337 spi_message_add_tail(&req->xfer[1], &req->msg);
338
339
340 command |= ADS_PD10_REF_ON;
341 }
342
343
344 command |= ADS_PD10_ADC_ON;
345
346
347 req->command = (u8) command;
348 req->xfer[2].tx_buf = &req->command;
349 req->xfer[2].len = 1;
350 spi_message_add_tail(&req->xfer[2], &req->msg);
351
352 req->xfer[3].rx_buf = &req->sample;
353 req->xfer[3].len = 2;
354 spi_message_add_tail(&req->xfer[3], &req->msg);
355
356
357
358
359 req->ref_off = PWRDOWN;
360 req->xfer[4].tx_buf = &req->ref_off;
361 req->xfer[4].len = 1;
362 spi_message_add_tail(&req->xfer[4], &req->msg);
363
364 req->xfer[5].rx_buf = &req->scratch;
365 req->xfer[5].len = 2;
366 CS_CHANGE(req->xfer[5]);
367 spi_message_add_tail(&req->xfer[5], &req->msg);
368
369 mutex_lock(&ts->lock);
370 ads7846_stop(ts);
371 status = spi_sync(spi, &req->msg);
372 ads7846_restart(ts);
373 mutex_unlock(&ts->lock);
374
375 if (status == 0) {
376
377 status = be16_to_cpu(req->sample);
378 status = status >> 3;
379 status &= 0x0fff;
380 }
381
382 kfree(req);
383 return status;
384}
385
386static int ads7845_read12_ser(struct device *dev, unsigned command)
387{
388 struct spi_device *spi = to_spi_device(dev);
389 struct ads7846 *ts = dev_get_drvdata(dev);
390 struct ads7845_ser_req *req;
391 int status;
392
393 req = kzalloc(sizeof *req, GFP_KERNEL);
394 if (!req)
395 return -ENOMEM;
396
397 spi_message_init(&req->msg);
398
399 req->command[0] = (u8) command;
400 req->xfer[0].tx_buf = req->command;
401 req->xfer[0].rx_buf = req->sample;
402 req->xfer[0].len = 3;
403 spi_message_add_tail(&req->xfer[0], &req->msg);
404
405 mutex_lock(&ts->lock);
406 ads7846_stop(ts);
407 status = spi_sync(spi, &req->msg);
408 ads7846_restart(ts);
409 mutex_unlock(&ts->lock);
410
411 if (status == 0) {
412
413 status = be16_to_cpu(*((u16 *)&req->sample[1]));
414 status = status >> 3;
415 status &= 0x0fff;
416 }
417
418 kfree(req);
419 return status;
420}
421
422#if IS_ENABLED(CONFIG_HWMON)
423
424#define SHOW(name, var, adjust) static ssize_t \
425name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \
426{ \
427 struct ads7846 *ts = dev_get_drvdata(dev); \
428 ssize_t v = ads7846_read12_ser(&ts->spi->dev, \
429 READ_12BIT_SER(var)); \
430 if (v < 0) \
431 return v; \
432 return sprintf(buf, "%u\n", adjust(ts, v)); \
433} \
434static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL);
435
436
437
438
439
440
441
442static inline unsigned null_adjust(struct ads7846 *ts, ssize_t v)
443{
444 return v;
445}
446
447SHOW(temp0, temp0, null_adjust)
448SHOW(temp1, temp1, null_adjust)
449
450
451
452
453
454
455static inline unsigned vaux_adjust(struct ads7846 *ts, ssize_t v)
456{
457 unsigned retval = v;
458
459
460 retval *= ts->vref_mv;
461 retval = retval >> 12;
462
463 return retval;
464}
465
466static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v)
467{
468 unsigned retval = vaux_adjust(ts, v);
469
470
471 if (ts->model == 7846)
472 retval *= 4;
473
474 return retval;
475}
476
477SHOW(in0_input, vaux, vaux_adjust)
478SHOW(in1_input, vbatt, vbatt_adjust)
479
480static umode_t ads7846_is_visible(struct kobject *kobj, struct attribute *attr,
481 int index)
482{
483 struct device *dev = container_of(kobj, struct device, kobj);
484 struct ads7846 *ts = dev_get_drvdata(dev);
485
486 if (ts->model == 7843 && index < 2)
487 return 0;
488 if (ts->model == 7845 && index != 2)
489 return 0;
490
491 return attr->mode;
492}
493
494static struct attribute *ads7846_attributes[] = {
495 &dev_attr_temp0.attr,
496 &dev_attr_temp1.attr,
497 &dev_attr_in0_input.attr,
498 &dev_attr_in1_input.attr,
499 NULL,
500};
501
502static struct attribute_group ads7846_attr_group = {
503 .attrs = ads7846_attributes,
504 .is_visible = ads7846_is_visible,
505};
506__ATTRIBUTE_GROUPS(ads7846_attr);
507
508static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts)
509{
510
511 switch (ts->model) {
512 case 7846:
513 if (!ts->vref_mv) {
514 dev_dbg(&spi->dev, "assuming 2.5V internal vREF\n");
515 ts->vref_mv = 2500;
516 ts->use_internal = true;
517 }
518 break;
519 case 7845:
520 case 7843:
521 if (!ts->vref_mv) {
522 dev_warn(&spi->dev,
523 "external vREF for ADS%d not specified\n",
524 ts->model);
525 return 0;
526 }
527 break;
528 }
529
530 ts->hwmon = hwmon_device_register_with_groups(&spi->dev, spi->modalias,
531 ts, ads7846_attr_groups);
532 if (IS_ERR(ts->hwmon))
533 return PTR_ERR(ts->hwmon);
534
535 return 0;
536}
537
538static void ads784x_hwmon_unregister(struct spi_device *spi,
539 struct ads7846 *ts)
540{
541 if (ts->hwmon)
542 hwmon_device_unregister(ts->hwmon);
543}
544
545#else
546static inline int ads784x_hwmon_register(struct spi_device *spi,
547 struct ads7846 *ts)
548{
549 return 0;
550}
551
552static inline void ads784x_hwmon_unregister(struct spi_device *spi,
553 struct ads7846 *ts)
554{
555}
556#endif
557
558static ssize_t ads7846_pen_down_show(struct device *dev,
559 struct device_attribute *attr, char *buf)
560{
561 struct ads7846 *ts = dev_get_drvdata(dev);
562
563 return sprintf(buf, "%u\n", ts->pendown);
564}
565
566static DEVICE_ATTR(pen_down, S_IRUGO, ads7846_pen_down_show, NULL);
567
568static ssize_t ads7846_disable_show(struct device *dev,
569 struct device_attribute *attr, char *buf)
570{
571 struct ads7846 *ts = dev_get_drvdata(dev);
572
573 return sprintf(buf, "%u\n", ts->disabled);
574}
575
576static ssize_t ads7846_disable_store(struct device *dev,
577 struct device_attribute *attr,
578 const char *buf, size_t count)
579{
580 struct ads7846 *ts = dev_get_drvdata(dev);
581 unsigned int i;
582 int err;
583
584 err = kstrtouint(buf, 10, &i);
585 if (err)
586 return err;
587
588 if (i)
589 ads7846_disable(ts);
590 else
591 ads7846_enable(ts);
592
593 return count;
594}
595
596static DEVICE_ATTR(disable, 0664, ads7846_disable_show, ads7846_disable_store);
597
598static struct attribute *ads784x_attributes[] = {
599 &dev_attr_pen_down.attr,
600 &dev_attr_disable.attr,
601 NULL,
602};
603
604static struct attribute_group ads784x_attr_group = {
605 .attrs = ads784x_attributes,
606};
607
608
609
610static int get_pendown_state(struct ads7846 *ts)
611{
612 if (ts->get_pendown_state)
613 return ts->get_pendown_state();
614
615 return !gpio_get_value(ts->gpio_pendown);
616}
617
618static void null_wait_for_sync(void)
619{
620}
621
622static int ads7846_debounce_filter(void *ads, int data_idx, int *val)
623{
624 struct ads7846 *ts = ads;
625
626 if (!ts->read_cnt || (abs(ts->last_read - *val) > ts->debounce_tol)) {
627
628 ts->read_rep = 0;
629
630
631
632
633 if (ts->read_cnt < ts->debounce_max) {
634 ts->last_read = *val;
635 ts->read_cnt++;
636 return ADS7846_FILTER_REPEAT;
637 } else {
638
639
640
641
642
643
644 ts->read_cnt = 0;
645 return ADS7846_FILTER_IGNORE;
646 }
647 } else {
648 if (++ts->read_rep > ts->debounce_rep) {
649
650
651
652
653 ts->read_cnt = 0;
654 ts->read_rep = 0;
655 return ADS7846_FILTER_OK;
656 } else {
657
658 ts->read_cnt++;
659 return ADS7846_FILTER_REPEAT;
660 }
661 }
662}
663
664static int ads7846_no_filter(void *ads, int data_idx, int *val)
665{
666 return ADS7846_FILTER_OK;
667}
668
669static int ads7846_get_value(struct ads7846 *ts, struct spi_message *m)
670{
671 struct spi_transfer *t =
672 list_entry(m->transfers.prev, struct spi_transfer, transfer_list);
673
674 if (ts->model == 7845) {
675 return be16_to_cpup((__be16 *)&(((char*)t->rx_buf)[1])) >> 3;
676 } else {
677
678
679
680
681 return be16_to_cpup((__be16 *)t->rx_buf) >> 3;
682 }
683}
684
685static void ads7846_update_value(struct spi_message *m, int val)
686{
687 struct spi_transfer *t =
688 list_entry(m->transfers.prev, struct spi_transfer, transfer_list);
689
690 *(u16 *)t->rx_buf = val;
691}
692
693static void ads7846_read_state(struct ads7846 *ts)
694{
695 struct ads7846_packet *packet = ts->packet;
696 struct spi_message *m;
697 int msg_idx = 0;
698 int val;
699 int action;
700 int error;
701
702 while (msg_idx < ts->msg_count) {
703
704 ts->wait_for_sync();
705
706 m = &ts->msg[msg_idx];
707 error = spi_sync(ts->spi, m);
708 if (error) {
709 dev_err(&ts->spi->dev, "spi_sync --> %d\n", error);
710 packet->tc.ignore = true;
711 return;
712 }
713
714
715
716
717
718 if (msg_idx < ts->msg_count - 1) {
719
720 val = ads7846_get_value(ts, m);
721
722 action = ts->filter(ts->filter_data, msg_idx, &val);
723 switch (action) {
724 case ADS7846_FILTER_REPEAT:
725 continue;
726
727 case ADS7846_FILTER_IGNORE:
728 packet->tc.ignore = true;
729 msg_idx = ts->msg_count - 1;
730 continue;
731
732 case ADS7846_FILTER_OK:
733 ads7846_update_value(m, val);
734 packet->tc.ignore = false;
735 msg_idx++;
736 break;
737
738 default:
739 BUG();
740 }
741 } else {
742 msg_idx++;
743 }
744 }
745}
746
747static void ads7846_report_state(struct ads7846 *ts)
748{
749 struct ads7846_packet *packet = ts->packet;
750 unsigned int Rt;
751 u16 x, y, z1, z2;
752
753
754
755
756
757
758 if (ts->model == 7845) {
759 x = *(u16 *)packet->tc.x_buf;
760 y = *(u16 *)packet->tc.y_buf;
761 z1 = 0;
762 z2 = 0;
763 } else {
764 x = packet->tc.x;
765 y = packet->tc.y;
766 z1 = packet->tc.z1;
767 z2 = packet->tc.z2;
768 }
769
770
771 if (x == MAX_12BIT)
772 x = 0;
773
774 if (ts->model == 7843) {
775 Rt = ts->pressure_max / 2;
776 } else if (ts->model == 7845) {
777 if (get_pendown_state(ts))
778 Rt = ts->pressure_max / 2;
779 else
780 Rt = 0;
781 dev_vdbg(&ts->spi->dev, "x/y: %d/%d, PD %d\n", x, y, Rt);
782 } else if (likely(x && z1)) {
783
784 Rt = z2;
785 Rt -= z1;
786 Rt *= x;
787 Rt *= ts->x_plate_ohms;
788 Rt /= z1;
789 Rt = (Rt + 2047) >> 12;
790 } else {
791 Rt = 0;
792 }
793
794
795
796
797
798
799 if (packet->tc.ignore || Rt > ts->pressure_max) {
800 dev_vdbg(&ts->spi->dev, "ignored %d pressure %d\n",
801 packet->tc.ignore, Rt);
802 return;
803 }
804
805
806
807
808
809 if (ts->penirq_recheck_delay_usecs) {
810 udelay(ts->penirq_recheck_delay_usecs);
811 if (!get_pendown_state(ts))
812 Rt = 0;
813 }
814
815
816
817
818
819
820
821
822
823
824 if (Rt) {
825 struct input_dev *input = ts->input;
826
827 if (ts->swap_xy)
828 swap(x, y);
829
830 if (!ts->pendown) {
831 input_report_key(input, BTN_TOUCH, 1);
832 ts->pendown = true;
833 dev_vdbg(&ts->spi->dev, "DOWN\n");
834 }
835
836 input_report_abs(input, ABS_X, x);
837 input_report_abs(input, ABS_Y, y);
838 input_report_abs(input, ABS_PRESSURE, ts->pressure_max - Rt);
839
840 input_sync(input);
841 dev_vdbg(&ts->spi->dev, "%4d/%4d/%4d\n", x, y, Rt);
842 }
843}
844
845static irqreturn_t ads7846_hard_irq(int irq, void *handle)
846{
847 struct ads7846 *ts = handle;
848
849 return get_pendown_state(ts) ? IRQ_WAKE_THREAD : IRQ_HANDLED;
850}
851
852
853static irqreturn_t ads7846_irq(int irq, void *handle)
854{
855 struct ads7846 *ts = handle;
856
857
858 msleep(TS_POLL_DELAY);
859
860 while (!ts->stopped && get_pendown_state(ts)) {
861
862
863 ads7846_read_state(ts);
864
865 if (!ts->stopped)
866 ads7846_report_state(ts);
867
868 wait_event_timeout(ts->wait, ts->stopped,
869 msecs_to_jiffies(TS_POLL_PERIOD));
870 }
871
872 if (ts->pendown) {
873 struct input_dev *input = ts->input;
874
875 input_report_key(input, BTN_TOUCH, 0);
876 input_report_abs(input, ABS_PRESSURE, 0);
877 input_sync(input);
878
879 ts->pendown = false;
880 dev_vdbg(&ts->spi->dev, "UP\n");
881 }
882
883 return IRQ_HANDLED;
884}
885
886#ifdef CONFIG_PM_SLEEP
887static int ads7846_suspend(struct device *dev)
888{
889 struct ads7846 *ts = dev_get_drvdata(dev);
890
891 mutex_lock(&ts->lock);
892
893 if (!ts->suspended) {
894
895 if (!ts->disabled)
896 __ads7846_disable(ts);
897
898 if (device_may_wakeup(&ts->spi->dev))
899 enable_irq_wake(ts->spi->irq);
900
901 ts->suspended = true;
902 }
903
904 mutex_unlock(&ts->lock);
905
906 return 0;
907}
908
909static int ads7846_resume(struct device *dev)
910{
911 struct ads7846 *ts = dev_get_drvdata(dev);
912
913 mutex_lock(&ts->lock);
914
915 if (ts->suspended) {
916
917 ts->suspended = false;
918
919 if (device_may_wakeup(&ts->spi->dev))
920 disable_irq_wake(ts->spi->irq);
921
922 if (!ts->disabled)
923 __ads7846_enable(ts);
924 }
925
926 mutex_unlock(&ts->lock);
927
928 return 0;
929}
930#endif
931
932static SIMPLE_DEV_PM_OPS(ads7846_pm, ads7846_suspend, ads7846_resume);
933
934static int ads7846_setup_pendown(struct spi_device *spi,
935 struct ads7846 *ts,
936 const struct ads7846_platform_data *pdata)
937{
938 int err;
939
940
941
942
943
944
945
946 if (pdata->get_pendown_state) {
947 ts->get_pendown_state = pdata->get_pendown_state;
948 } else if (gpio_is_valid(pdata->gpio_pendown)) {
949
950 err = gpio_request_one(pdata->gpio_pendown, GPIOF_IN,
951 "ads7846_pendown");
952 if (err) {
953 dev_err(&spi->dev,
954 "failed to request/setup pendown GPIO%d: %d\n",
955 pdata->gpio_pendown, err);
956 return err;
957 }
958
959 ts->gpio_pendown = pdata->gpio_pendown;
960
961 if (pdata->gpio_pendown_debounce)
962 gpio_set_debounce(pdata->gpio_pendown,
963 pdata->gpio_pendown_debounce);
964 } else {
965 dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
966 return -EINVAL;
967 }
968
969 return 0;
970}
971
972
973
974
975
976static void ads7846_setup_spi_msg(struct ads7846 *ts,
977 const struct ads7846_platform_data *pdata)
978{
979 struct spi_message *m = &ts->msg[0];
980 struct spi_transfer *x = ts->xfer;
981 struct ads7846_packet *packet = ts->packet;
982 int vref = pdata->keep_vref_on;
983
984 if (ts->model == 7873) {
985
986
987
988
989
990 ts->model = 7846;
991 vref = 0;
992 }
993
994 ts->msg_count = 1;
995 spi_message_init(m);
996 m->context = ts;
997
998 if (ts->model == 7845) {
999 packet->read_y_cmd[0] = READ_Y(vref);
1000 packet->read_y_cmd[1] = 0;
1001 packet->read_y_cmd[2] = 0;
1002 x->tx_buf = &packet->read_y_cmd[0];
1003 x->rx_buf = &packet->tc.y_buf[0];
1004 x->len = 3;
1005 spi_message_add_tail(x, m);
1006 } else {
1007
1008 packet->read_y = READ_Y(vref);
1009 x->tx_buf = &packet->read_y;
1010 x->len = 1;
1011 spi_message_add_tail(x, m);
1012
1013 x++;
1014 x->rx_buf = &packet->tc.y;
1015 x->len = 2;
1016 spi_message_add_tail(x, m);
1017 }
1018
1019
1020
1021
1022
1023
1024 if (pdata->settle_delay_usecs) {
1025 x->delay_usecs = pdata->settle_delay_usecs;
1026
1027 x++;
1028 x->tx_buf = &packet->read_y;
1029 x->len = 1;
1030 spi_message_add_tail(x, m);
1031
1032 x++;
1033 x->rx_buf = &packet->tc.y;
1034 x->len = 2;
1035 spi_message_add_tail(x, m);
1036 }
1037
1038 ts->msg_count++;
1039 m++;
1040 spi_message_init(m);
1041 m->context = ts;
1042
1043 if (ts->model == 7845) {
1044 x++;
1045 packet->read_x_cmd[0] = READ_X(vref);
1046 packet->read_x_cmd[1] = 0;
1047 packet->read_x_cmd[2] = 0;
1048 x->tx_buf = &packet->read_x_cmd[0];
1049 x->rx_buf = &packet->tc.x_buf[0];
1050 x->len = 3;
1051 spi_message_add_tail(x, m);
1052 } else {
1053
1054 x++;
1055 packet->read_x = READ_X(vref);
1056 x->tx_buf = &packet->read_x;
1057 x->len = 1;
1058 spi_message_add_tail(x, m);
1059
1060 x++;
1061 x->rx_buf = &packet->tc.x;
1062 x->len = 2;
1063 spi_message_add_tail(x, m);
1064 }
1065
1066
1067 if (pdata->settle_delay_usecs) {
1068 x->delay_usecs = pdata->settle_delay_usecs;
1069
1070 x++;
1071 x->tx_buf = &packet->read_x;
1072 x->len = 1;
1073 spi_message_add_tail(x, m);
1074
1075 x++;
1076 x->rx_buf = &packet->tc.x;
1077 x->len = 2;
1078 spi_message_add_tail(x, m);
1079 }
1080
1081
1082 if (ts->model == 7846) {
1083 ts->msg_count++;
1084 m++;
1085 spi_message_init(m);
1086 m->context = ts;
1087
1088 x++;
1089 packet->read_z1 = READ_Z1(vref);
1090 x->tx_buf = &packet->read_z1;
1091 x->len = 1;
1092 spi_message_add_tail(x, m);
1093
1094 x++;
1095 x->rx_buf = &packet->tc.z1;
1096 x->len = 2;
1097 spi_message_add_tail(x, m);
1098
1099
1100 if (pdata->settle_delay_usecs) {
1101 x->delay_usecs = pdata->settle_delay_usecs;
1102
1103 x++;
1104 x->tx_buf = &packet->read_z1;
1105 x->len = 1;
1106 spi_message_add_tail(x, m);
1107
1108 x++;
1109 x->rx_buf = &packet->tc.z1;
1110 x->len = 2;
1111 spi_message_add_tail(x, m);
1112 }
1113
1114 ts->msg_count++;
1115 m++;
1116 spi_message_init(m);
1117 m->context = ts;
1118
1119 x++;
1120 packet->read_z2 = READ_Z2(vref);
1121 x->tx_buf = &packet->read_z2;
1122 x->len = 1;
1123 spi_message_add_tail(x, m);
1124
1125 x++;
1126 x->rx_buf = &packet->tc.z2;
1127 x->len = 2;
1128 spi_message_add_tail(x, m);
1129
1130
1131 if (pdata->settle_delay_usecs) {
1132 x->delay_usecs = pdata->settle_delay_usecs;
1133
1134 x++;
1135 x->tx_buf = &packet->read_z2;
1136 x->len = 1;
1137 spi_message_add_tail(x, m);
1138
1139 x++;
1140 x->rx_buf = &packet->tc.z2;
1141 x->len = 2;
1142 spi_message_add_tail(x, m);
1143 }
1144 }
1145
1146
1147 ts->msg_count++;
1148 m++;
1149 spi_message_init(m);
1150 m->context = ts;
1151
1152 if (ts->model == 7845) {
1153 x++;
1154 packet->pwrdown_cmd[0] = PWRDOWN;
1155 packet->pwrdown_cmd[1] = 0;
1156 packet->pwrdown_cmd[2] = 0;
1157 x->tx_buf = &packet->pwrdown_cmd[0];
1158 x->len = 3;
1159 } else {
1160 x++;
1161 packet->pwrdown = PWRDOWN;
1162 x->tx_buf = &packet->pwrdown;
1163 x->len = 1;
1164 spi_message_add_tail(x, m);
1165
1166 x++;
1167 x->rx_buf = &packet->dummy;
1168 x->len = 2;
1169 }
1170
1171 CS_CHANGE(*x);
1172 spi_message_add_tail(x, m);
1173}
1174
1175#ifdef CONFIG_OF
1176static const struct of_device_id ads7846_dt_ids[] = {
1177 { .compatible = "ti,tsc2046", .data = (void *) 7846 },
1178 { .compatible = "ti,ads7843", .data = (void *) 7843 },
1179 { .compatible = "ti,ads7845", .data = (void *) 7845 },
1180 { .compatible = "ti,ads7846", .data = (void *) 7846 },
1181 { .compatible = "ti,ads7873", .data = (void *) 7873 },
1182 { }
1183};
1184MODULE_DEVICE_TABLE(of, ads7846_dt_ids);
1185
1186static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev)
1187{
1188 struct ads7846_platform_data *pdata;
1189 struct device_node *node = dev->of_node;
1190 const struct of_device_id *match;
1191
1192 if (!node) {
1193 dev_err(dev, "Device does not have associated DT data\n");
1194 return ERR_PTR(-EINVAL);
1195 }
1196
1197 match = of_match_device(ads7846_dt_ids, dev);
1198 if (!match) {
1199 dev_err(dev, "Unknown device model\n");
1200 return ERR_PTR(-EINVAL);
1201 }
1202
1203 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
1204 if (!pdata)
1205 return ERR_PTR(-ENOMEM);
1206
1207 pdata->model = (unsigned long)match->data;
1208
1209 of_property_read_u16(node, "ti,vref-delay-usecs",
1210 &pdata->vref_delay_usecs);
1211 of_property_read_u16(node, "ti,vref-mv", &pdata->vref_mv);
1212 pdata->keep_vref_on = of_property_read_bool(node, "ti,keep-vref-on");
1213
1214 pdata->swap_xy = of_property_read_bool(node, "ti,swap-xy");
1215
1216 of_property_read_u16(node, "ti,settle-delay-usec",
1217 &pdata->settle_delay_usecs);
1218 of_property_read_u16(node, "ti,penirq-recheck-delay-usecs",
1219 &pdata->penirq_recheck_delay_usecs);
1220
1221 of_property_read_u16(node, "ti,x-plate-ohms", &pdata->x_plate_ohms);
1222 of_property_read_u16(node, "ti,y-plate-ohms", &pdata->y_plate_ohms);
1223
1224 of_property_read_u16(node, "ti,x-min", &pdata->x_min);
1225 of_property_read_u16(node, "ti,y-min", &pdata->y_min);
1226 of_property_read_u16(node, "ti,x-max", &pdata->x_max);
1227 of_property_read_u16(node, "ti,y-max", &pdata->y_max);
1228
1229 of_property_read_u16(node, "ti,pressure-min", &pdata->pressure_min);
1230 of_property_read_u16(node, "ti,pressure-max", &pdata->pressure_max);
1231
1232 of_property_read_u16(node, "ti,debounce-max", &pdata->debounce_max);
1233 of_property_read_u16(node, "ti,debounce-tol", &pdata->debounce_tol);
1234 of_property_read_u16(node, "ti,debounce-rep", &pdata->debounce_rep);
1235
1236 of_property_read_u32(node, "ti,pendown-gpio-debounce",
1237 &pdata->gpio_pendown_debounce);
1238
1239 pdata->wakeup = of_property_read_bool(node, "linux,wakeup");
1240
1241 pdata->gpio_pendown = of_get_named_gpio(dev->of_node, "pendown-gpio", 0);
1242
1243 return pdata;
1244}
1245#else
1246static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev)
1247{
1248 dev_err(dev, "no platform data defined\n");
1249 return ERR_PTR(-EINVAL);
1250}
1251#endif
1252
1253static int ads7846_probe(struct spi_device *spi)
1254{
1255 const struct ads7846_platform_data *pdata;
1256 struct ads7846 *ts;
1257 struct ads7846_packet *packet;
1258 struct input_dev *input_dev;
1259 unsigned long irq_flags;
1260 int err;
1261
1262 if (!spi->irq) {
1263 dev_dbg(&spi->dev, "no IRQ?\n");
1264 return -EINVAL;
1265 }
1266
1267
1268 if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) {
1269 dev_err(&spi->dev, "f(sample) %d KHz?\n",
1270 (spi->max_speed_hz/SAMPLE_BITS)/1000);
1271 return -EINVAL;
1272 }
1273
1274
1275
1276
1277
1278
1279 spi->bits_per_word = 8;
1280 spi->mode = SPI_MODE_0;
1281 err = spi_setup(spi);
1282 if (err < 0)
1283 return err;
1284
1285 ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL);
1286 packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL);
1287 input_dev = input_allocate_device();
1288 if (!ts || !packet || !input_dev) {
1289 err = -ENOMEM;
1290 goto err_free_mem;
1291 }
1292
1293 spi_set_drvdata(spi, ts);
1294
1295 ts->packet = packet;
1296 ts->spi = spi;
1297 ts->input = input_dev;
1298
1299 mutex_init(&ts->lock);
1300 init_waitqueue_head(&ts->wait);
1301
1302 pdata = dev_get_platdata(&spi->dev);
1303 if (!pdata) {
1304 pdata = ads7846_probe_dt(&spi->dev);
1305 if (IS_ERR(pdata)) {
1306 err = PTR_ERR(pdata);
1307 goto err_free_mem;
1308 }
1309 }
1310
1311 ts->model = pdata->model ? : 7846;
1312 ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100;
1313 ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
1314 ts->pressure_max = pdata->pressure_max ? : ~0;
1315
1316 ts->vref_mv = pdata->vref_mv;
1317 ts->swap_xy = pdata->swap_xy;
1318
1319 if (pdata->filter != NULL) {
1320 if (pdata->filter_init != NULL) {
1321 err = pdata->filter_init(pdata, &ts->filter_data);
1322 if (err < 0)
1323 goto err_free_mem;
1324 }
1325 ts->filter = pdata->filter;
1326 ts->filter_cleanup = pdata->filter_cleanup;
1327 } else if (pdata->debounce_max) {
1328 ts->debounce_max = pdata->debounce_max;
1329 if (ts->debounce_max < 2)
1330 ts->debounce_max = 2;
1331 ts->debounce_tol = pdata->debounce_tol;
1332 ts->debounce_rep = pdata->debounce_rep;
1333 ts->filter = ads7846_debounce_filter;
1334 ts->filter_data = ts;
1335 } else {
1336 ts->filter = ads7846_no_filter;
1337 }
1338
1339 err = ads7846_setup_pendown(spi, ts, pdata);
1340 if (err)
1341 goto err_cleanup_filter;
1342
1343 if (pdata->penirq_recheck_delay_usecs)
1344 ts->penirq_recheck_delay_usecs =
1345 pdata->penirq_recheck_delay_usecs;
1346
1347 ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync;
1348
1349 snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev));
1350 snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model);
1351
1352 input_dev->name = ts->name;
1353 input_dev->phys = ts->phys;
1354 input_dev->dev.parent = &spi->dev;
1355
1356 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
1357 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
1358 input_set_abs_params(input_dev, ABS_X,
1359 pdata->x_min ? : 0,
1360 pdata->x_max ? : MAX_12BIT,
1361 0, 0);
1362 input_set_abs_params(input_dev, ABS_Y,
1363 pdata->y_min ? : 0,
1364 pdata->y_max ? : MAX_12BIT,
1365 0, 0);
1366 input_set_abs_params(input_dev, ABS_PRESSURE,
1367 pdata->pressure_min, pdata->pressure_max, 0, 0);
1368
1369 ads7846_setup_spi_msg(ts, pdata);
1370
1371 ts->reg = regulator_get(&spi->dev, "vcc");
1372 if (IS_ERR(ts->reg)) {
1373 err = PTR_ERR(ts->reg);
1374 dev_err(&spi->dev, "unable to get regulator: %d\n", err);
1375 goto err_free_gpio;
1376 }
1377
1378 err = regulator_enable(ts->reg);
1379 if (err) {
1380 dev_err(&spi->dev, "unable to enable regulator: %d\n", err);
1381 goto err_put_regulator;
1382 }
1383
1384 irq_flags = pdata->irq_flags ? : IRQF_TRIGGER_FALLING;
1385 irq_flags |= IRQF_ONESHOT;
1386
1387 err = request_threaded_irq(spi->irq, ads7846_hard_irq, ads7846_irq,
1388 irq_flags, spi->dev.driver->name, ts);
1389 if (err && !pdata->irq_flags) {
1390 dev_info(&spi->dev,
1391 "trying pin change workaround on irq %d\n", spi->irq);
1392 irq_flags |= IRQF_TRIGGER_RISING;
1393 err = request_threaded_irq(spi->irq,
1394 ads7846_hard_irq, ads7846_irq,
1395 irq_flags, spi->dev.driver->name, ts);
1396 }
1397
1398 if (err) {
1399 dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
1400 goto err_disable_regulator;
1401 }
1402
1403 err = ads784x_hwmon_register(spi, ts);
1404 if (err)
1405 goto err_free_irq;
1406
1407 dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq);
1408
1409
1410
1411
1412
1413 if (ts->model == 7845)
1414 ads7845_read12_ser(&spi->dev, PWRDOWN);
1415 else
1416 (void) ads7846_read12_ser(&spi->dev, READ_12BIT_SER(vaux));
1417
1418 err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group);
1419 if (err)
1420 goto err_remove_hwmon;
1421
1422 err = input_register_device(input_dev);
1423 if (err)
1424 goto err_remove_attr_group;
1425
1426 device_init_wakeup(&spi->dev, pdata->wakeup);
1427
1428
1429
1430
1431
1432 if (!dev_get_platdata(&spi->dev))
1433 devm_kfree(&spi->dev, (void *)pdata);
1434
1435 return 0;
1436
1437 err_remove_attr_group:
1438 sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group);
1439 err_remove_hwmon:
1440 ads784x_hwmon_unregister(spi, ts);
1441 err_free_irq:
1442 free_irq(spi->irq, ts);
1443 err_disable_regulator:
1444 regulator_disable(ts->reg);
1445 err_put_regulator:
1446 regulator_put(ts->reg);
1447 err_free_gpio:
1448 if (!ts->get_pendown_state)
1449 gpio_free(ts->gpio_pendown);
1450 err_cleanup_filter:
1451 if (ts->filter_cleanup)
1452 ts->filter_cleanup(ts->filter_data);
1453 err_free_mem:
1454 input_free_device(input_dev);
1455 kfree(packet);
1456 kfree(ts);
1457 return err;
1458}
1459
1460static int ads7846_remove(struct spi_device *spi)
1461{
1462 struct ads7846 *ts = spi_get_drvdata(spi);
1463
1464 device_init_wakeup(&spi->dev, false);
1465
1466 sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group);
1467
1468 ads7846_disable(ts);
1469 free_irq(ts->spi->irq, ts);
1470
1471 input_unregister_device(ts->input);
1472
1473 ads784x_hwmon_unregister(spi, ts);
1474
1475 regulator_disable(ts->reg);
1476 regulator_put(ts->reg);
1477
1478 if (!ts->get_pendown_state) {
1479
1480
1481
1482
1483 gpio_free(ts->gpio_pendown);
1484 }
1485
1486 if (ts->filter_cleanup)
1487 ts->filter_cleanup(ts->filter_data);
1488
1489 kfree(ts->packet);
1490 kfree(ts);
1491
1492 dev_dbg(&spi->dev, "unregistered touchscreen\n");
1493
1494 return 0;
1495}
1496
1497static struct spi_driver ads7846_driver = {
1498 .driver = {
1499 .name = "ads7846",
1500 .owner = THIS_MODULE,
1501 .pm = &ads7846_pm,
1502 .of_match_table = of_match_ptr(ads7846_dt_ids),
1503 },
1504 .probe = ads7846_probe,
1505 .remove = ads7846_remove,
1506};
1507
1508module_spi_driver(ads7846_driver);
1509
1510MODULE_DESCRIPTION("ADS7846 TouchScreen Driver");
1511MODULE_LICENSE("GPL");
1512MODULE_ALIAS("spi:ads7846");
1513