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30#include <linux/delay.h>
31#include <linux/input.h>
32#include <linux/input/mt.h>
33#include <linux/input/touchscreen.h>
34#include <linux/gpio.h>
35#include <linux/interrupt.h>
36#include <linux/slab.h>
37#include <linux/property.h>
38#include <linux/gpio/consumer.h>
39
40#include "cyttsp_core.h"
41
42
43#define CY_NUM_BL_KEYS 8
44
45
46#define GET_NUM_TOUCHES(x) ((x) & 0x0F)
47#define IS_LARGE_AREA(x) (((x) & 0x10) >> 4)
48#define IS_BAD_PKT(x) ((x) & 0x20)
49#define IS_VALID_APP(x) ((x) & 0x01)
50#define IS_OPERATIONAL_ERR(x) ((x) & 0x3F)
51#define GET_HSTMODE(reg) (((reg) & 0x70) >> 4)
52#define GET_BOOTLOADERMODE(reg) (((reg) & 0x10) >> 4)
53
54#define CY_REG_BASE 0x00
55#define CY_REG_ACT_DIST 0x1E
56#define CY_REG_ACT_INTRVL 0x1D
57#define CY_REG_TCH_TMOUT (CY_REG_ACT_INTRVL + 1)
58#define CY_REG_LP_INTRVL (CY_REG_TCH_TMOUT + 1)
59#define CY_MAXZ 255
60#define CY_DELAY_DFLT 20
61#define CY_DELAY_MAX 500
62#define CY_ACT_DIST_DFLT 0xF8
63#define CY_ACT_DIST_MASK 0x0F
64#define CY_HNDSHK_BIT 0x80
65
66#define CY_OPERATE_MODE 0x00
67#define CY_SYSINFO_MODE 0x10
68
69#define CY_SOFT_RESET_MODE 0x01
70#define CY_DEEP_SLEEP_MODE 0x02
71#define CY_LOW_POWER_MODE 0x04
72
73
74#define CY_MAX_FINGER 4
75#define CY_MAX_ID 16
76
77static const u8 bl_command[] = {
78 0x00,
79 0xFF,
80 0xA5,
81 0, 1, 2, 3, 4, 5, 6, 7
82};
83
84static int ttsp_read_block_data(struct cyttsp *ts, u8 command,
85 u8 length, void *buf)
86{
87 int error;
88 int tries;
89
90 for (tries = 0; tries < CY_NUM_RETRY; tries++) {
91 error = ts->bus_ops->read(ts->dev, ts->xfer_buf, command,
92 length, buf);
93 if (!error)
94 return 0;
95
96 msleep(CY_DELAY_DFLT);
97 }
98
99 return -EIO;
100}
101
102static int ttsp_write_block_data(struct cyttsp *ts, u8 command,
103 u8 length, void *buf)
104{
105 int error;
106 int tries;
107
108 for (tries = 0; tries < CY_NUM_RETRY; tries++) {
109 error = ts->bus_ops->write(ts->dev, ts->xfer_buf, command,
110 length, buf);
111 if (!error)
112 return 0;
113
114 msleep(CY_DELAY_DFLT);
115 }
116
117 return -EIO;
118}
119
120static int ttsp_send_command(struct cyttsp *ts, u8 cmd)
121{
122 return ttsp_write_block_data(ts, CY_REG_BASE, sizeof(cmd), &cmd);
123}
124
125static int cyttsp_handshake(struct cyttsp *ts)
126{
127 if (ts->use_hndshk)
128 return ttsp_send_command(ts,
129 ts->xy_data.hst_mode ^ CY_HNDSHK_BIT);
130
131 return 0;
132}
133
134static int cyttsp_load_bl_regs(struct cyttsp *ts)
135{
136 memset(&ts->bl_data, 0, sizeof(ts->bl_data));
137 ts->bl_data.bl_status = 0x10;
138
139 return ttsp_read_block_data(ts, CY_REG_BASE,
140 sizeof(ts->bl_data), &ts->bl_data);
141}
142
143static int cyttsp_exit_bl_mode(struct cyttsp *ts)
144{
145 int error;
146 u8 bl_cmd[sizeof(bl_command)];
147
148 memcpy(bl_cmd, bl_command, sizeof(bl_command));
149 if (ts->bl_keys)
150 memcpy(&bl_cmd[sizeof(bl_command) - CY_NUM_BL_KEYS],
151 ts->bl_keys, CY_NUM_BL_KEYS);
152
153 error = ttsp_write_block_data(ts, CY_REG_BASE,
154 sizeof(bl_cmd), bl_cmd);
155 if (error)
156 return error;
157
158
159 msleep(CY_DELAY_DFLT);
160
161 error = cyttsp_load_bl_regs(ts);
162 if (error)
163 return error;
164
165 if (GET_BOOTLOADERMODE(ts->bl_data.bl_status))
166 return -EIO;
167
168 return 0;
169}
170
171static int cyttsp_set_operational_mode(struct cyttsp *ts)
172{
173 int error;
174
175 error = ttsp_send_command(ts, CY_OPERATE_MODE);
176 if (error)
177 return error;
178
179
180 error = ttsp_read_block_data(ts, CY_REG_BASE,
181 sizeof(ts->xy_data), &ts->xy_data);
182 if (error)
183 return error;
184
185 error = cyttsp_handshake(ts);
186 if (error)
187 return error;
188
189 return ts->xy_data.act_dist == CY_ACT_DIST_DFLT ? -EIO : 0;
190}
191
192static int cyttsp_set_sysinfo_mode(struct cyttsp *ts)
193{
194 int error;
195
196 memset(&ts->sysinfo_data, 0, sizeof(ts->sysinfo_data));
197
198
199 error = ttsp_send_command(ts, CY_SYSINFO_MODE);
200 if (error)
201 return error;
202
203
204 msleep(CY_DELAY_DFLT);
205 error = ttsp_read_block_data(ts, CY_REG_BASE, sizeof(ts->sysinfo_data),
206 &ts->sysinfo_data);
207 if (error)
208 return error;
209
210 error = cyttsp_handshake(ts);
211 if (error)
212 return error;
213
214 if (!ts->sysinfo_data.tts_verh && !ts->sysinfo_data.tts_verl)
215 return -EIO;
216
217 return 0;
218}
219
220static int cyttsp_set_sysinfo_regs(struct cyttsp *ts)
221{
222 int retval = 0;
223
224 if (ts->act_intrvl != CY_ACT_INTRVL_DFLT ||
225 ts->tch_tmout != CY_TCH_TMOUT_DFLT ||
226 ts->lp_intrvl != CY_LP_INTRVL_DFLT) {
227
228 u8 intrvl_ray[] = {
229 ts->act_intrvl,
230 ts->tch_tmout,
231 ts->lp_intrvl
232 };
233
234
235 retval = ttsp_write_block_data(ts, CY_REG_ACT_INTRVL,
236 sizeof(intrvl_ray), intrvl_ray);
237 msleep(CY_DELAY_DFLT);
238 }
239
240 return retval;
241}
242
243static void cyttsp_hard_reset(struct cyttsp *ts)
244{
245 if (ts->reset_gpio) {
246 gpiod_set_value_cansleep(ts->reset_gpio, 1);
247 msleep(CY_DELAY_DFLT);
248 gpiod_set_value_cansleep(ts->reset_gpio, 0);
249 msleep(CY_DELAY_DFLT);
250 }
251}
252
253static int cyttsp_soft_reset(struct cyttsp *ts)
254{
255 unsigned long timeout;
256 int retval;
257
258
259 reinit_completion(&ts->bl_ready);
260 ts->state = CY_BL_STATE;
261
262 enable_irq(ts->irq);
263
264 retval = ttsp_send_command(ts, CY_SOFT_RESET_MODE);
265 if (retval)
266 goto out;
267
268 timeout = wait_for_completion_timeout(&ts->bl_ready,
269 msecs_to_jiffies(CY_DELAY_DFLT * CY_DELAY_MAX));
270 retval = timeout ? 0 : -EIO;
271
272out:
273 ts->state = CY_IDLE_STATE;
274 disable_irq(ts->irq);
275 return retval;
276}
277
278static int cyttsp_act_dist_setup(struct cyttsp *ts)
279{
280 u8 act_dist_setup = ts->act_dist;
281
282
283 return ttsp_write_block_data(ts, CY_REG_ACT_DIST,
284 sizeof(act_dist_setup), &act_dist_setup);
285}
286
287static void cyttsp_extract_track_ids(struct cyttsp_xydata *xy_data, int *ids)
288{
289 ids[0] = xy_data->touch12_id >> 4;
290 ids[1] = xy_data->touch12_id & 0xF;
291 ids[2] = xy_data->touch34_id >> 4;
292 ids[3] = xy_data->touch34_id & 0xF;
293}
294
295static const struct cyttsp_tch *cyttsp_get_tch(struct cyttsp_xydata *xy_data,
296 int idx)
297{
298 switch (idx) {
299 case 0:
300 return &xy_data->tch1;
301 case 1:
302 return &xy_data->tch2;
303 case 2:
304 return &xy_data->tch3;
305 case 3:
306 return &xy_data->tch4;
307 default:
308 return NULL;
309 }
310}
311
312static void cyttsp_report_tchdata(struct cyttsp *ts)
313{
314 struct cyttsp_xydata *xy_data = &ts->xy_data;
315 struct input_dev *input = ts->input;
316 int num_tch = GET_NUM_TOUCHES(xy_data->tt_stat);
317 const struct cyttsp_tch *tch;
318 int ids[CY_MAX_ID];
319 int i;
320 DECLARE_BITMAP(used, CY_MAX_ID);
321
322 if (IS_LARGE_AREA(xy_data->tt_stat) == 1) {
323
324 num_tch = 0;
325 dev_dbg(ts->dev, "%s: Large area detected\n", __func__);
326 } else if (num_tch > CY_MAX_FINGER) {
327
328 num_tch = 0;
329 dev_dbg(ts->dev, "%s: Num touch error detected\n", __func__);
330 } else if (IS_BAD_PKT(xy_data->tt_mode)) {
331
332 num_tch = 0;
333 dev_dbg(ts->dev, "%s: Invalid buffer detected\n", __func__);
334 }
335
336 cyttsp_extract_track_ids(xy_data, ids);
337
338 bitmap_zero(used, CY_MAX_ID);
339
340 for (i = 0; i < num_tch; i++) {
341 tch = cyttsp_get_tch(xy_data, i);
342
343 input_mt_slot(input, ids[i]);
344 input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
345 input_report_abs(input, ABS_MT_POSITION_X, be16_to_cpu(tch->x));
346 input_report_abs(input, ABS_MT_POSITION_Y, be16_to_cpu(tch->y));
347 input_report_abs(input, ABS_MT_TOUCH_MAJOR, tch->z);
348
349 __set_bit(ids[i], used);
350 }
351
352 for (i = 0; i < CY_MAX_ID; i++) {
353 if (test_bit(i, used))
354 continue;
355
356 input_mt_slot(input, i);
357 input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
358 }
359
360 input_sync(input);
361}
362
363static irqreturn_t cyttsp_irq(int irq, void *handle)
364{
365 struct cyttsp *ts = handle;
366 int error;
367
368 if (unlikely(ts->state == CY_BL_STATE)) {
369 complete(&ts->bl_ready);
370 goto out;
371 }
372
373
374 error = ttsp_read_block_data(ts, CY_REG_BASE,
375 sizeof(struct cyttsp_xydata), &ts->xy_data);
376 if (error)
377 goto out;
378
379
380 error = cyttsp_handshake(ts);
381 if (error)
382 goto out;
383
384 if (unlikely(ts->state == CY_IDLE_STATE))
385 goto out;
386
387 if (GET_BOOTLOADERMODE(ts->xy_data.tt_mode)) {
388
389
390
391
392 error = cyttsp_exit_bl_mode(ts);
393 if (error) {
394 dev_err(ts->dev,
395 "Could not return to operational mode, err: %d\n",
396 error);
397 ts->state = CY_IDLE_STATE;
398 }
399 } else {
400 cyttsp_report_tchdata(ts);
401 }
402
403out:
404 return IRQ_HANDLED;
405}
406
407static int cyttsp_power_on(struct cyttsp *ts)
408{
409 int error;
410
411 error = cyttsp_soft_reset(ts);
412 if (error)
413 return error;
414
415 error = cyttsp_load_bl_regs(ts);
416 if (error)
417 return error;
418
419 if (GET_BOOTLOADERMODE(ts->bl_data.bl_status) &&
420 IS_VALID_APP(ts->bl_data.bl_status)) {
421 error = cyttsp_exit_bl_mode(ts);
422 if (error)
423 return error;
424 }
425
426 if (GET_HSTMODE(ts->bl_data.bl_file) != CY_OPERATE_MODE ||
427 IS_OPERATIONAL_ERR(ts->bl_data.bl_status)) {
428 return -ENODEV;
429 }
430
431 error = cyttsp_set_sysinfo_mode(ts);
432 if (error)
433 return error;
434
435 error = cyttsp_set_sysinfo_regs(ts);
436 if (error)
437 return error;
438
439 error = cyttsp_set_operational_mode(ts);
440 if (error)
441 return error;
442
443
444 error = cyttsp_act_dist_setup(ts);
445 if (error)
446 return error;
447
448 ts->state = CY_ACTIVE_STATE;
449
450 return 0;
451}
452
453static int cyttsp_enable(struct cyttsp *ts)
454{
455 int error;
456
457
458
459
460
461
462
463 error = ttsp_read_block_data(ts, CY_REG_BASE,
464 sizeof(ts->xy_data), &ts->xy_data);
465 if (error)
466 return error;
467
468 if (GET_HSTMODE(ts->xy_data.hst_mode))
469 return -EIO;
470
471 enable_irq(ts->irq);
472
473 return 0;
474}
475
476static int cyttsp_disable(struct cyttsp *ts)
477{
478 int error;
479
480 error = ttsp_send_command(ts, CY_LOW_POWER_MODE);
481 if (error)
482 return error;
483
484 disable_irq(ts->irq);
485
486 return 0;
487}
488
489static int __maybe_unused cyttsp_suspend(struct device *dev)
490{
491 struct cyttsp *ts = dev_get_drvdata(dev);
492 int retval = 0;
493
494 mutex_lock(&ts->input->mutex);
495
496 if (ts->input->users) {
497 retval = cyttsp_disable(ts);
498 if (retval == 0)
499 ts->suspended = true;
500 }
501
502 mutex_unlock(&ts->input->mutex);
503
504 return retval;
505}
506
507static int __maybe_unused cyttsp_resume(struct device *dev)
508{
509 struct cyttsp *ts = dev_get_drvdata(dev);
510
511 mutex_lock(&ts->input->mutex);
512
513 if (ts->input->users)
514 cyttsp_enable(ts);
515
516 ts->suspended = false;
517
518 mutex_unlock(&ts->input->mutex);
519
520 return 0;
521}
522
523SIMPLE_DEV_PM_OPS(cyttsp_pm_ops, cyttsp_suspend, cyttsp_resume);
524EXPORT_SYMBOL_GPL(cyttsp_pm_ops);
525
526static int cyttsp_open(struct input_dev *dev)
527{
528 struct cyttsp *ts = input_get_drvdata(dev);
529 int retval = 0;
530
531 if (!ts->suspended)
532 retval = cyttsp_enable(ts);
533
534 return retval;
535}
536
537static void cyttsp_close(struct input_dev *dev)
538{
539 struct cyttsp *ts = input_get_drvdata(dev);
540
541 if (!ts->suspended)
542 cyttsp_disable(ts);
543}
544
545static int cyttsp_parse_properties(struct cyttsp *ts)
546{
547 struct device *dev = ts->dev;
548 u32 dt_value;
549 int ret;
550
551 ts->bl_keys = devm_kzalloc(dev, CY_NUM_BL_KEYS, GFP_KERNEL);
552 if (!ts->bl_keys)
553 return -ENOMEM;
554
555
556 ts->use_hndshk = false;
557 ts->act_dist = CY_ACT_DIST_DFLT;
558 ts->act_intrvl = CY_ACT_INTRVL_DFLT;
559 ts->tch_tmout = CY_TCH_TMOUT_DFLT;
560 ts->lp_intrvl = CY_LP_INTRVL_DFLT;
561
562 ret = device_property_read_u8_array(dev, "bootloader-key",
563 ts->bl_keys, CY_NUM_BL_KEYS);
564 if (ret) {
565 dev_err(dev,
566 "bootloader-key property could not be retrieved\n");
567 return ret;
568 }
569
570 ts->use_hndshk = device_property_present(dev, "use-handshake");
571
572 if (!device_property_read_u32(dev, "active-distance", &dt_value)) {
573 if (dt_value > 15) {
574 dev_err(dev, "active-distance (%u) must be [0-15]\n",
575 dt_value);
576 return -EINVAL;
577 }
578 ts->act_dist &= ~CY_ACT_DIST_MASK;
579 ts->act_dist |= dt_value;
580 }
581
582 if (!device_property_read_u32(dev, "active-interval-ms", &dt_value)) {
583 if (dt_value > 255) {
584 dev_err(dev, "active-interval-ms (%u) must be [0-255]\n",
585 dt_value);
586 return -EINVAL;
587 }
588 ts->act_intrvl = dt_value;
589 }
590
591 if (!device_property_read_u32(dev, "lowpower-interval-ms", &dt_value)) {
592 if (dt_value > 2550) {
593 dev_err(dev, "lowpower-interval-ms (%u) must be [0-2550]\n",
594 dt_value);
595 return -EINVAL;
596 }
597
598 ts->lp_intrvl = dt_value / 10;
599 }
600
601 if (!device_property_read_u32(dev, "touch-timeout-ms", &dt_value)) {
602 if (dt_value > 2550) {
603 dev_err(dev, "touch-timeout-ms (%u) must be [0-2550]\n",
604 dt_value);
605 return -EINVAL;
606 }
607
608 ts->tch_tmout = dt_value / 10;
609 }
610
611 return 0;
612}
613
614struct cyttsp *cyttsp_probe(const struct cyttsp_bus_ops *bus_ops,
615 struct device *dev, int irq, size_t xfer_buf_size)
616{
617 struct cyttsp *ts;
618 struct input_dev *input_dev;
619 int error;
620
621 ts = devm_kzalloc(dev, sizeof(*ts) + xfer_buf_size, GFP_KERNEL);
622 if (!ts)
623 return ERR_PTR(-ENOMEM);
624
625 input_dev = devm_input_allocate_device(dev);
626 if (!input_dev)
627 return ERR_PTR(-ENOMEM);
628
629 ts->dev = dev;
630 ts->input = input_dev;
631 ts->bus_ops = bus_ops;
632 ts->irq = irq;
633
634 ts->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
635 if (IS_ERR(ts->reset_gpio)) {
636 error = PTR_ERR(ts->reset_gpio);
637 dev_err(dev, "Failed to request reset gpio, error %d\n", error);
638 return ERR_PTR(error);
639 }
640
641 error = cyttsp_parse_properties(ts);
642 if (error)
643 return ERR_PTR(error);
644
645 init_completion(&ts->bl_ready);
646 snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));
647
648 input_dev->name = "Cypress TTSP TouchScreen";
649 input_dev->phys = ts->phys;
650 input_dev->id.bustype = bus_ops->bustype;
651 input_dev->dev.parent = ts->dev;
652
653 input_dev->open = cyttsp_open;
654 input_dev->close = cyttsp_close;
655
656 input_set_drvdata(input_dev, ts);
657
658 input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X);
659 input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y);
660 touchscreen_parse_properties(input_dev, true);
661
662 error = input_mt_init_slots(input_dev, CY_MAX_ID, 0);
663 if (error) {
664 dev_err(dev, "Unable to init MT slots.\n");
665 return ERR_PTR(error);
666 }
667
668 error = devm_request_threaded_irq(dev, ts->irq, NULL, cyttsp_irq,
669 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
670 "cyttsp", ts);
671 if (error) {
672 dev_err(ts->dev, "failed to request IRQ %d, err: %d\n",
673 ts->irq, error);
674 return ERR_PTR(error);
675 }
676
677 disable_irq(ts->irq);
678
679 cyttsp_hard_reset(ts);
680
681 error = cyttsp_power_on(ts);
682 if (error)
683 return ERR_PTR(error);
684
685 error = input_register_device(input_dev);
686 if (error) {
687 dev_err(ts->dev, "failed to register input device: %d\n",
688 error);
689 return ERR_PTR(error);
690 }
691
692 return ts;
693}
694EXPORT_SYMBOL_GPL(cyttsp_probe);
695
696MODULE_LICENSE("GPL");
697MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard touchscreen driver core");
698MODULE_AUTHOR("Cypress");
699
