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16#include <linux/delay.h>
17#include <linux/input.h>
18#include <linux/input/mt.h>
19#include <linux/input/touchscreen.h>
20#include <linux/gpio.h>
21#include <linux/interrupt.h>
22#include <linux/slab.h>
23#include <linux/property.h>
24#include <linux/gpio/consumer.h>
25
26#include "cyttsp_core.h"
27
28
29#define CY_NUM_BL_KEYS 8
30
31
32#define GET_NUM_TOUCHES(x) ((x) & 0x0F)
33#define IS_LARGE_AREA(x) (((x) & 0x10) >> 4)
34#define IS_BAD_PKT(x) ((x) & 0x20)
35#define IS_VALID_APP(x) ((x) & 0x01)
36#define IS_OPERATIONAL_ERR(x) ((x) & 0x3F)
37#define GET_HSTMODE(reg) (((reg) & 0x70) >> 4)
38#define GET_BOOTLOADERMODE(reg) (((reg) & 0x10) >> 4)
39
40#define CY_REG_BASE 0x00
41#define CY_REG_ACT_DIST 0x1E
42#define CY_REG_ACT_INTRVL 0x1D
43#define CY_REG_TCH_TMOUT (CY_REG_ACT_INTRVL + 1)
44#define CY_REG_LP_INTRVL (CY_REG_TCH_TMOUT + 1)
45#define CY_MAXZ 255
46#define CY_DELAY_DFLT 20
47#define CY_DELAY_MAX 500
48#define CY_ACT_DIST_DFLT 0xF8
49#define CY_ACT_DIST_MASK 0x0F
50#define CY_HNDSHK_BIT 0x80
51
52#define CY_OPERATE_MODE 0x00
53#define CY_SYSINFO_MODE 0x10
54
55#define CY_SOFT_RESET_MODE 0x01
56#define CY_DEEP_SLEEP_MODE 0x02
57#define CY_LOW_POWER_MODE 0x04
58
59
60#define CY_MAX_FINGER 4
61#define CY_MAX_ID 16
62
63static const u8 bl_command[] = {
64 0x00,
65 0xFF,
66 0xA5,
67 0, 1, 2, 3, 4, 5, 6, 7
68};
69
70static int ttsp_read_block_data(struct cyttsp *ts, u8 command,
71 u8 length, void *buf)
72{
73 int error;
74 int tries;
75
76 for (tries = 0; tries < CY_NUM_RETRY; tries++) {
77 error = ts->bus_ops->read(ts->dev, ts->xfer_buf, command,
78 length, buf);
79 if (!error)
80 return 0;
81
82 msleep(CY_DELAY_DFLT);
83 }
84
85 return -EIO;
86}
87
88static int ttsp_write_block_data(struct cyttsp *ts, u8 command,
89 u8 length, void *buf)
90{
91 int error;
92 int tries;
93
94 for (tries = 0; tries < CY_NUM_RETRY; tries++) {
95 error = ts->bus_ops->write(ts->dev, ts->xfer_buf, command,
96 length, buf);
97 if (!error)
98 return 0;
99
100 msleep(CY_DELAY_DFLT);
101 }
102
103 return -EIO;
104}
105
106static int ttsp_send_command(struct cyttsp *ts, u8 cmd)
107{
108 return ttsp_write_block_data(ts, CY_REG_BASE, sizeof(cmd), &cmd);
109}
110
111static int cyttsp_handshake(struct cyttsp *ts)
112{
113 if (ts->use_hndshk)
114 return ttsp_send_command(ts,
115 ts->xy_data.hst_mode ^ CY_HNDSHK_BIT);
116
117 return 0;
118}
119
120static int cyttsp_load_bl_regs(struct cyttsp *ts)
121{
122 memset(&ts->bl_data, 0, sizeof(ts->bl_data));
123 ts->bl_data.bl_status = 0x10;
124
125 return ttsp_read_block_data(ts, CY_REG_BASE,
126 sizeof(ts->bl_data), &ts->bl_data);
127}
128
129static int cyttsp_exit_bl_mode(struct cyttsp *ts)
130{
131 int error;
132 u8 bl_cmd[sizeof(bl_command)];
133
134 memcpy(bl_cmd, bl_command, sizeof(bl_command));
135 if (ts->bl_keys)
136 memcpy(&bl_cmd[sizeof(bl_command) - CY_NUM_BL_KEYS],
137 ts->bl_keys, CY_NUM_BL_KEYS);
138
139 error = ttsp_write_block_data(ts, CY_REG_BASE,
140 sizeof(bl_cmd), bl_cmd);
141 if (error)
142 return error;
143
144
145 msleep(CY_DELAY_DFLT);
146
147 error = cyttsp_load_bl_regs(ts);
148 if (error)
149 return error;
150
151 if (GET_BOOTLOADERMODE(ts->bl_data.bl_status))
152 return -EIO;
153
154 return 0;
155}
156
157static int cyttsp_set_operational_mode(struct cyttsp *ts)
158{
159 int error;
160
161 error = ttsp_send_command(ts, CY_OPERATE_MODE);
162 if (error)
163 return error;
164
165
166 error = ttsp_read_block_data(ts, CY_REG_BASE,
167 sizeof(ts->xy_data), &ts->xy_data);
168 if (error)
169 return error;
170
171 error = cyttsp_handshake(ts);
172 if (error)
173 return error;
174
175 return ts->xy_data.act_dist == CY_ACT_DIST_DFLT ? -EIO : 0;
176}
177
178static int cyttsp_set_sysinfo_mode(struct cyttsp *ts)
179{
180 int error;
181
182 memset(&ts->sysinfo_data, 0, sizeof(ts->sysinfo_data));
183
184
185 error = ttsp_send_command(ts, CY_SYSINFO_MODE);
186 if (error)
187 return error;
188
189
190 msleep(CY_DELAY_DFLT);
191 error = ttsp_read_block_data(ts, CY_REG_BASE, sizeof(ts->sysinfo_data),
192 &ts->sysinfo_data);
193 if (error)
194 return error;
195
196 error = cyttsp_handshake(ts);
197 if (error)
198 return error;
199
200 if (!ts->sysinfo_data.tts_verh && !ts->sysinfo_data.tts_verl)
201 return -EIO;
202
203 return 0;
204}
205
206static int cyttsp_set_sysinfo_regs(struct cyttsp *ts)
207{
208 int retval = 0;
209
210 if (ts->act_intrvl != CY_ACT_INTRVL_DFLT ||
211 ts->tch_tmout != CY_TCH_TMOUT_DFLT ||
212 ts->lp_intrvl != CY_LP_INTRVL_DFLT) {
213
214 u8 intrvl_ray[] = {
215 ts->act_intrvl,
216 ts->tch_tmout,
217 ts->lp_intrvl
218 };
219
220
221 retval = ttsp_write_block_data(ts, CY_REG_ACT_INTRVL,
222 sizeof(intrvl_ray), intrvl_ray);
223 msleep(CY_DELAY_DFLT);
224 }
225
226 return retval;
227}
228
229static void cyttsp_hard_reset(struct cyttsp *ts)
230{
231 if (ts->reset_gpio) {
232 gpiod_set_value_cansleep(ts->reset_gpio, 1);
233 msleep(CY_DELAY_DFLT);
234 gpiod_set_value_cansleep(ts->reset_gpio, 0);
235 msleep(CY_DELAY_DFLT);
236 }
237}
238
239static int cyttsp_soft_reset(struct cyttsp *ts)
240{
241 unsigned long timeout;
242 int retval;
243
244
245 reinit_completion(&ts->bl_ready);
246 ts->state = CY_BL_STATE;
247
248 enable_irq(ts->irq);
249
250 retval = ttsp_send_command(ts, CY_SOFT_RESET_MODE);
251 if (retval)
252 goto out;
253
254 timeout = wait_for_completion_timeout(&ts->bl_ready,
255 msecs_to_jiffies(CY_DELAY_DFLT * CY_DELAY_MAX));
256 retval = timeout ? 0 : -EIO;
257
258out:
259 ts->state = CY_IDLE_STATE;
260 disable_irq(ts->irq);
261 return retval;
262}
263
264static int cyttsp_act_dist_setup(struct cyttsp *ts)
265{
266 u8 act_dist_setup = ts->act_dist;
267
268
269 return ttsp_write_block_data(ts, CY_REG_ACT_DIST,
270 sizeof(act_dist_setup), &act_dist_setup);
271}
272
273static void cyttsp_extract_track_ids(struct cyttsp_xydata *xy_data, int *ids)
274{
275 ids[0] = xy_data->touch12_id >> 4;
276 ids[1] = xy_data->touch12_id & 0xF;
277 ids[2] = xy_data->touch34_id >> 4;
278 ids[3] = xy_data->touch34_id & 0xF;
279}
280
281static const struct cyttsp_tch *cyttsp_get_tch(struct cyttsp_xydata *xy_data,
282 int idx)
283{
284 switch (idx) {
285 case 0:
286 return &xy_data->tch1;
287 case 1:
288 return &xy_data->tch2;
289 case 2:
290 return &xy_data->tch3;
291 case 3:
292 return &xy_data->tch4;
293 default:
294 return NULL;
295 }
296}
297
298static void cyttsp_report_tchdata(struct cyttsp *ts)
299{
300 struct cyttsp_xydata *xy_data = &ts->xy_data;
301 struct input_dev *input = ts->input;
302 int num_tch = GET_NUM_TOUCHES(xy_data->tt_stat);
303 const struct cyttsp_tch *tch;
304 int ids[CY_MAX_ID];
305 int i;
306 DECLARE_BITMAP(used, CY_MAX_ID);
307
308 if (IS_LARGE_AREA(xy_data->tt_stat) == 1) {
309
310 num_tch = 0;
311 dev_dbg(ts->dev, "%s: Large area detected\n", __func__);
312 } else if (num_tch > CY_MAX_FINGER) {
313
314 num_tch = 0;
315 dev_dbg(ts->dev, "%s: Num touch error detected\n", __func__);
316 } else if (IS_BAD_PKT(xy_data->tt_mode)) {
317
318 num_tch = 0;
319 dev_dbg(ts->dev, "%s: Invalid buffer detected\n", __func__);
320 }
321
322 cyttsp_extract_track_ids(xy_data, ids);
323
324 bitmap_zero(used, CY_MAX_ID);
325
326 for (i = 0; i < num_tch; i++) {
327 tch = cyttsp_get_tch(xy_data, i);
328
329 input_mt_slot(input, ids[i]);
330 input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
331 input_report_abs(input, ABS_MT_POSITION_X, be16_to_cpu(tch->x));
332 input_report_abs(input, ABS_MT_POSITION_Y, be16_to_cpu(tch->y));
333 input_report_abs(input, ABS_MT_TOUCH_MAJOR, tch->z);
334
335 __set_bit(ids[i], used);
336 }
337
338 for (i = 0; i < CY_MAX_ID; i++) {
339 if (test_bit(i, used))
340 continue;
341
342 input_mt_slot(input, i);
343 input_mt_report_slot_inactive(input);
344 }
345
346 input_sync(input);
347}
348
349static irqreturn_t cyttsp_irq(int irq, void *handle)
350{
351 struct cyttsp *ts = handle;
352 int error;
353
354 if (unlikely(ts->state == CY_BL_STATE)) {
355 complete(&ts->bl_ready);
356 goto out;
357 }
358
359
360 error = ttsp_read_block_data(ts, CY_REG_BASE,
361 sizeof(struct cyttsp_xydata), &ts->xy_data);
362 if (error)
363 goto out;
364
365
366 error = cyttsp_handshake(ts);
367 if (error)
368 goto out;
369
370 if (unlikely(ts->state == CY_IDLE_STATE))
371 goto out;
372
373 if (GET_BOOTLOADERMODE(ts->xy_data.tt_mode)) {
374
375
376
377
378 error = cyttsp_exit_bl_mode(ts);
379 if (error) {
380 dev_err(ts->dev,
381 "Could not return to operational mode, err: %d\n",
382 error);
383 ts->state = CY_IDLE_STATE;
384 }
385 } else {
386 cyttsp_report_tchdata(ts);
387 }
388
389out:
390 return IRQ_HANDLED;
391}
392
393static int cyttsp_power_on(struct cyttsp *ts)
394{
395 int error;
396
397 error = cyttsp_soft_reset(ts);
398 if (error)
399 return error;
400
401 error = cyttsp_load_bl_regs(ts);
402 if (error)
403 return error;
404
405 if (GET_BOOTLOADERMODE(ts->bl_data.bl_status) &&
406 IS_VALID_APP(ts->bl_data.bl_status)) {
407 error = cyttsp_exit_bl_mode(ts);
408 if (error)
409 return error;
410 }
411
412 if (GET_HSTMODE(ts->bl_data.bl_file) != CY_OPERATE_MODE ||
413 IS_OPERATIONAL_ERR(ts->bl_data.bl_status)) {
414 return -ENODEV;
415 }
416
417 error = cyttsp_set_sysinfo_mode(ts);
418 if (error)
419 return error;
420
421 error = cyttsp_set_sysinfo_regs(ts);
422 if (error)
423 return error;
424
425 error = cyttsp_set_operational_mode(ts);
426 if (error)
427 return error;
428
429
430 error = cyttsp_act_dist_setup(ts);
431 if (error)
432 return error;
433
434 ts->state = CY_ACTIVE_STATE;
435
436 return 0;
437}
438
439static int cyttsp_enable(struct cyttsp *ts)
440{
441 int error;
442
443
444
445
446
447
448
449 error = ttsp_read_block_data(ts, CY_REG_BASE,
450 sizeof(ts->xy_data), &ts->xy_data);
451 if (error)
452 return error;
453
454 if (GET_HSTMODE(ts->xy_data.hst_mode))
455 return -EIO;
456
457 enable_irq(ts->irq);
458
459 return 0;
460}
461
462static int cyttsp_disable(struct cyttsp *ts)
463{
464 int error;
465
466 error = ttsp_send_command(ts, CY_LOW_POWER_MODE);
467 if (error)
468 return error;
469
470 disable_irq(ts->irq);
471
472 return 0;
473}
474
475static int __maybe_unused cyttsp_suspend(struct device *dev)
476{
477 struct cyttsp *ts = dev_get_drvdata(dev);
478 int retval = 0;
479
480 mutex_lock(&ts->input->mutex);
481
482 if (input_device_enabled(ts->input)) {
483 retval = cyttsp_disable(ts);
484 if (retval == 0)
485 ts->suspended = true;
486 }
487
488 mutex_unlock(&ts->input->mutex);
489
490 return retval;
491}
492
493static int __maybe_unused cyttsp_resume(struct device *dev)
494{
495 struct cyttsp *ts = dev_get_drvdata(dev);
496
497 mutex_lock(&ts->input->mutex);
498
499 if (input_device_enabled(ts->input))
500 cyttsp_enable(ts);
501
502 ts->suspended = false;
503
504 mutex_unlock(&ts->input->mutex);
505
506 return 0;
507}
508
509SIMPLE_DEV_PM_OPS(cyttsp_pm_ops, cyttsp_suspend, cyttsp_resume);
510EXPORT_SYMBOL_GPL(cyttsp_pm_ops);
511
512static int cyttsp_open(struct input_dev *dev)
513{
514 struct cyttsp *ts = input_get_drvdata(dev);
515 int retval = 0;
516
517 if (!ts->suspended)
518 retval = cyttsp_enable(ts);
519
520 return retval;
521}
522
523static void cyttsp_close(struct input_dev *dev)
524{
525 struct cyttsp *ts = input_get_drvdata(dev);
526
527 if (!ts->suspended)
528 cyttsp_disable(ts);
529}
530
531static int cyttsp_parse_properties(struct cyttsp *ts)
532{
533 struct device *dev = ts->dev;
534 u32 dt_value;
535 int ret;
536
537 ts->bl_keys = devm_kzalloc(dev, CY_NUM_BL_KEYS, GFP_KERNEL);
538 if (!ts->bl_keys)
539 return -ENOMEM;
540
541
542 ts->use_hndshk = false;
543 ts->act_dist = CY_ACT_DIST_DFLT;
544 ts->act_intrvl = CY_ACT_INTRVL_DFLT;
545 ts->tch_tmout = CY_TCH_TMOUT_DFLT;
546 ts->lp_intrvl = CY_LP_INTRVL_DFLT;
547
548 ret = device_property_read_u8_array(dev, "bootloader-key",
549 ts->bl_keys, CY_NUM_BL_KEYS);
550 if (ret) {
551 dev_err(dev,
552 "bootloader-key property could not be retrieved\n");
553 return ret;
554 }
555
556 ts->use_hndshk = device_property_present(dev, "use-handshake");
557
558 if (!device_property_read_u32(dev, "active-distance", &dt_value)) {
559 if (dt_value > 15) {
560 dev_err(dev, "active-distance (%u) must be [0-15]\n",
561 dt_value);
562 return -EINVAL;
563 }
564 ts->act_dist &= ~CY_ACT_DIST_MASK;
565 ts->act_dist |= dt_value;
566 }
567
568 if (!device_property_read_u32(dev, "active-interval-ms", &dt_value)) {
569 if (dt_value > 255) {
570 dev_err(dev, "active-interval-ms (%u) must be [0-255]\n",
571 dt_value);
572 return -EINVAL;
573 }
574 ts->act_intrvl = dt_value;
575 }
576
577 if (!device_property_read_u32(dev, "lowpower-interval-ms", &dt_value)) {
578 if (dt_value > 2550) {
579 dev_err(dev, "lowpower-interval-ms (%u) must be [0-2550]\n",
580 dt_value);
581 return -EINVAL;
582 }
583
584 ts->lp_intrvl = dt_value / 10;
585 }
586
587 if (!device_property_read_u32(dev, "touch-timeout-ms", &dt_value)) {
588 if (dt_value > 2550) {
589 dev_err(dev, "touch-timeout-ms (%u) must be [0-2550]\n",
590 dt_value);
591 return -EINVAL;
592 }
593
594 ts->tch_tmout = dt_value / 10;
595 }
596
597 return 0;
598}
599
600struct cyttsp *cyttsp_probe(const struct cyttsp_bus_ops *bus_ops,
601 struct device *dev, int irq, size_t xfer_buf_size)
602{
603 struct cyttsp *ts;
604 struct input_dev *input_dev;
605 int error;
606
607 ts = devm_kzalloc(dev, sizeof(*ts) + xfer_buf_size, GFP_KERNEL);
608 if (!ts)
609 return ERR_PTR(-ENOMEM);
610
611 input_dev = devm_input_allocate_device(dev);
612 if (!input_dev)
613 return ERR_PTR(-ENOMEM);
614
615 ts->dev = dev;
616 ts->input = input_dev;
617 ts->bus_ops = bus_ops;
618 ts->irq = irq;
619
620 ts->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
621 if (IS_ERR(ts->reset_gpio)) {
622 error = PTR_ERR(ts->reset_gpio);
623 dev_err(dev, "Failed to request reset gpio, error %d\n", error);
624 return ERR_PTR(error);
625 }
626
627 error = cyttsp_parse_properties(ts);
628 if (error)
629 return ERR_PTR(error);
630
631 init_completion(&ts->bl_ready);
632 snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));
633
634 input_dev->name = "Cypress TTSP TouchScreen";
635 input_dev->phys = ts->phys;
636 input_dev->id.bustype = bus_ops->bustype;
637 input_dev->dev.parent = ts->dev;
638
639 input_dev->open = cyttsp_open;
640 input_dev->close = cyttsp_close;
641
642 input_set_drvdata(input_dev, ts);
643
644 input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X);
645 input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y);
646 touchscreen_parse_properties(input_dev, true, NULL);
647
648 error = input_mt_init_slots(input_dev, CY_MAX_ID, 0);
649 if (error) {
650 dev_err(dev, "Unable to init MT slots.\n");
651 return ERR_PTR(error);
652 }
653
654 error = devm_request_threaded_irq(dev, ts->irq, NULL, cyttsp_irq,
655 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
656 "cyttsp", ts);
657 if (error) {
658 dev_err(ts->dev, "failed to request IRQ %d, err: %d\n",
659 ts->irq, error);
660 return ERR_PTR(error);
661 }
662
663 disable_irq(ts->irq);
664
665 cyttsp_hard_reset(ts);
666
667 error = cyttsp_power_on(ts);
668 if (error)
669 return ERR_PTR(error);
670
671 error = input_register_device(input_dev);
672 if (error) {
673 dev_err(ts->dev, "failed to register input device: %d\n",
674 error);
675 return ERR_PTR(error);
676 }
677
678 return ts;
679}
680EXPORT_SYMBOL_GPL(cyttsp_probe);
681
682MODULE_LICENSE("GPL");
683MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard touchscreen driver core");
684MODULE_AUTHOR("Cypress");
685
