1 // SPDX-License-Identifier: GPL-2.0-only
2
3 #include <linux/delay.h>
4 #include <linux/i2c.h>
5 #include <linux/input.h>
6 #include <linux/input/mt.h>
7 #include <linux/input/touchscreen.h>
8 #include <linux/interrupt.h>
9 #include <linux/irq.h>
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/regulator/consumer.h>
14 #include <linux/slab.h>
15
16 /* Register Map */
17
18 #define ZINITIX_SWRESET_CMD 0x0000
19 #define ZINITIX_WAKEUP_CMD 0x0001
20
21 #define ZINITIX_IDLE_CMD 0x0004
22 #define ZINITIX_SLEEP_CMD 0x0005
23
24 #define ZINITIX_CLEAR_INT_STATUS_CMD 0x0003
25 #define ZINITIX_CALIBRATE_CMD 0x0006
26 #define ZINITIX_SAVE_STATUS_CMD 0x0007
27 #define ZINITIX_SAVE_CALIBRATION_CMD 0x0008
28 #define ZINITIX_RECALL_FACTORY_CMD 0x000f
29
30 #define ZINITIX_THRESHOLD 0x0020
31
32 #define ZINITIX_LARGE_PALM_REJECT_AREA_TH 0x003F
33
34 #define ZINITIX_DEBUG_REG 0x0115 /* 0~7 */
35
36 #define ZINITIX_TOUCH_MODE 0x0010
37 #define ZINITIX_CHIP_REVISION 0x0011
38 #define ZINITIX_FIRMWARE_VERSION 0x0012
39
40 #define ZINITIX_USB_DETECT 0x116
41
42 #define ZINITIX_MINOR_FW_VERSION 0x0121
43
44 #define ZINITIX_VENDOR_ID 0x001C
45 #define ZINITIX_HW_ID 0x0014
46
47 #define ZINITIX_DATA_VERSION_REG 0x0013
48 #define ZINITIX_SUPPORTED_FINGER_NUM 0x0015
49 #define ZINITIX_EEPROM_INFO 0x0018
50 #define ZINITIX_INITIAL_TOUCH_MODE 0x0019
51
52 #define ZINITIX_TOTAL_NUMBER_OF_X 0x0060
53 #define ZINITIX_TOTAL_NUMBER_OF_Y 0x0061
54
55 #define ZINITIX_DELAY_RAW_FOR_HOST 0x007f
56
57 #define ZINITIX_BUTTON_SUPPORTED_NUM 0x00B0
58 #define ZINITIX_BUTTON_SENSITIVITY 0x00B2
59 #define ZINITIX_DUMMY_BUTTON_SENSITIVITY 0X00C8
60
61 #define ZINITIX_X_RESOLUTION 0x00C0
62 #define ZINITIX_Y_RESOLUTION 0x00C1
63
64 #define ZINITIX_POINT_STATUS_REG 0x0080
65 #define ZINITIX_ICON_STATUS_REG 0x00AA
66
67 #define ZINITIX_POINT_COORD_REG (ZINITIX_POINT_STATUS_REG + 2)
68
69 #define ZINITIX_AFE_FREQUENCY 0x0100
70 #define ZINITIX_DND_N_COUNT 0x0122
71 #define ZINITIX_DND_U_COUNT 0x0135
72
73 #define ZINITIX_RAWDATA_REG 0x0200
74
75 #define ZINITIX_EEPROM_INFO_REG 0x0018
76
77 #define ZINITIX_INT_ENABLE_FLAG 0x00f0
78 #define ZINITIX_PERIODICAL_INTERRUPT_INTERVAL 0x00f1
79
80 #define ZINITIX_BTN_WIDTH 0x016d
81
82 #define ZINITIX_CHECKSUM_RESULT 0x012c
83
84 #define ZINITIX_INIT_FLASH 0x01d0
85 #define ZINITIX_WRITE_FLASH 0x01d1
86 #define ZINITIX_READ_FLASH 0x01d2
87
88 #define ZINITIX_INTERNAL_FLAG_02 0x011e
89 #define ZINITIX_INTERNAL_FLAG_03 0x011f
90
91 #define ZINITIX_I2C_CHECKSUM_WCNT 0x016a
92 #define ZINITIX_I2C_CHECKSUM_RESULT 0x016c
93
94 /* Interrupt & status register flags */
95
96 #define BIT_PT_CNT_CHANGE BIT(0)
97 #define BIT_DOWN BIT(1)
98 #define BIT_MOVE BIT(2)
99 #define BIT_UP BIT(3)
100 #define BIT_PALM BIT(4)
101 #define BIT_PALM_REJECT BIT(5)
102 #define BIT_RESERVED_0 BIT(6)
103 #define BIT_RESERVED_1 BIT(7)
104 #define BIT_WEIGHT_CHANGE BIT(8)
105 #define BIT_PT_NO_CHANGE BIT(9)
106 #define BIT_REJECT BIT(10)
107 #define BIT_PT_EXIST BIT(11)
108 #define BIT_RESERVED_2 BIT(12)
109 #define BIT_ERROR BIT(13)
110 #define BIT_DEBUG BIT(14)
111 #define BIT_ICON_EVENT BIT(15)
112
113 #define SUB_BIT_EXIST BIT(0)
114 #define SUB_BIT_DOWN BIT(1)
115 #define SUB_BIT_MOVE BIT(2)
116 #define SUB_BIT_UP BIT(3)
117 #define SUB_BIT_UPDATE BIT(4)
118 #define SUB_BIT_WAIT BIT(5)
119
120 #define DEFAULT_TOUCH_POINT_MODE 2
121 #define MAX_SUPPORTED_FINGER_NUM 5
122
123 #define CHIP_ON_DELAY 15 // ms
124 #define FIRMWARE_ON_DELAY 40 // ms
125
126 struct point_coord {
127 __le16 x;
128 __le16 y;
129 u8 width;
130 u8 sub_status;
131 // currently unused, but needed as padding:
132 u8 minor_width;
133 u8 angle;
134 };
135
136 struct touch_event {
137 __le16 status;
138 u8 finger_mask;
139 u8 time_stamp;
140 struct point_coord point_coord[MAX_SUPPORTED_FINGER_NUM];
141 };
142
143 struct bt541_ts_data {
144 struct i2c_client *client;
145 struct input_dev *input_dev;
146 struct touchscreen_properties prop;
147 struct regulator_bulk_data supplies[2];
148 u32 zinitix_mode;
149 };
150
zinitix_read_data(struct i2c_client * client,u16 reg,void * values,size_t length)151 static int zinitix_read_data(struct i2c_client *client,
152 u16 reg, void *values, size_t length)
153 {
154 __le16 reg_le = cpu_to_le16(reg);
155 int ret;
156
157 /* A single i2c_transfer() transaction does not work here. */
158 ret = i2c_master_send(client, (u8 *)®_le, sizeof(reg_le));
159 if (ret != sizeof(reg_le))
160 return ret < 0 ? ret : -EIO;
161
162 ret = i2c_master_recv(client, (u8 *)values, length);
163 if (ret != length)
164 return ret < 0 ? ret : -EIO;
165
166 return 0;
167 }
168
zinitix_write_u16(struct i2c_client * client,u16 reg,u16 value)169 static int zinitix_write_u16(struct i2c_client *client, u16 reg, u16 value)
170 {
171 __le16 packet[2] = {cpu_to_le16(reg), cpu_to_le16(value)};
172 int ret;
173
174 ret = i2c_master_send(client, (u8 *)packet, sizeof(packet));
175 if (ret != sizeof(packet))
176 return ret < 0 ? ret : -EIO;
177
178 return 0;
179 }
180
zinitix_write_cmd(struct i2c_client * client,u16 reg)181 static int zinitix_write_cmd(struct i2c_client *client, u16 reg)
182 {
183 __le16 reg_le = cpu_to_le16(reg);
184 int ret;
185
186 ret = i2c_master_send(client, (u8 *)®_le, sizeof(reg_le));
187 if (ret != sizeof(reg_le))
188 return ret < 0 ? ret : -EIO;
189
190 return 0;
191 }
192
zinitix_init_touch(struct bt541_ts_data * bt541)193 static int zinitix_init_touch(struct bt541_ts_data *bt541)
194 {
195 struct i2c_client *client = bt541->client;
196 int i;
197 int error;
198
199 error = zinitix_write_cmd(client, ZINITIX_SWRESET_CMD);
200 if (error) {
201 dev_err(&client->dev, "Failed to write reset command\n");
202 return error;
203 }
204
205 error = zinitix_write_u16(client, ZINITIX_INT_ENABLE_FLAG, 0x0);
206 if (error) {
207 dev_err(&client->dev,
208 "Failed to reset interrupt enable flag\n");
209 return error;
210 }
211
212 /* initialize */
213 error = zinitix_write_u16(client, ZINITIX_X_RESOLUTION,
214 bt541->prop.max_x);
215 if (error)
216 return error;
217
218 error = zinitix_write_u16(client, ZINITIX_Y_RESOLUTION,
219 bt541->prop.max_y);
220 if (error)
221 return error;
222
223 error = zinitix_write_u16(client, ZINITIX_SUPPORTED_FINGER_NUM,
224 MAX_SUPPORTED_FINGER_NUM);
225 if (error)
226 return error;
227
228 error = zinitix_write_u16(client, ZINITIX_INITIAL_TOUCH_MODE,
229 bt541->zinitix_mode);
230 if (error)
231 return error;
232
233 error = zinitix_write_u16(client, ZINITIX_TOUCH_MODE,
234 bt541->zinitix_mode);
235 if (error)
236 return error;
237
238 error = zinitix_write_u16(client, ZINITIX_INT_ENABLE_FLAG,
239 BIT_PT_CNT_CHANGE | BIT_DOWN | BIT_MOVE |
240 BIT_UP);
241 if (error)
242 return error;
243
244 /* clear queue */
245 for (i = 0; i < 10; i++) {
246 zinitix_write_cmd(client, ZINITIX_CLEAR_INT_STATUS_CMD);
247 udelay(10);
248 }
249
250 return 0;
251 }
252
zinitix_init_regulators(struct bt541_ts_data * bt541)253 static int zinitix_init_regulators(struct bt541_ts_data *bt541)
254 {
255 struct device *dev = &bt541->client->dev;
256 int error;
257
258 /*
259 * Some older device trees have erroneous names for the regulators,
260 * so check if "vddo" is present and in that case use these names.
261 * Else use the proper supply names on the component.
262 */
263 if (of_property_present(dev->of_node, "vddo-supply")) {
264 bt541->supplies[0].supply = "vdd";
265 bt541->supplies[1].supply = "vddo";
266 } else {
267 /* Else use the proper supply names */
268 bt541->supplies[0].supply = "vcca";
269 bt541->supplies[1].supply = "vdd";
270 }
271 error = devm_regulator_bulk_get(dev,
272 ARRAY_SIZE(bt541->supplies),
273 bt541->supplies);
274 if (error < 0) {
275 dev_err(dev, "Failed to get regulators: %d\n", error);
276 return error;
277 }
278
279 return 0;
280 }
281
zinitix_send_power_on_sequence(struct bt541_ts_data * bt541)282 static int zinitix_send_power_on_sequence(struct bt541_ts_data *bt541)
283 {
284 int error;
285 struct i2c_client *client = bt541->client;
286
287 error = zinitix_write_u16(client, 0xc000, 0x0001);
288 if (error) {
289 dev_err(&client->dev,
290 "Failed to send power sequence(vendor cmd enable)\n");
291 return error;
292 }
293 udelay(10);
294
295 error = zinitix_write_cmd(client, 0xc004);
296 if (error) {
297 dev_err(&client->dev,
298 "Failed to send power sequence (intn clear)\n");
299 return error;
300 }
301 udelay(10);
302
303 error = zinitix_write_u16(client, 0xc002, 0x0001);
304 if (error) {
305 dev_err(&client->dev,
306 "Failed to send power sequence (nvm init)\n");
307 return error;
308 }
309 mdelay(2);
310
311 error = zinitix_write_u16(client, 0xc001, 0x0001);
312 if (error) {
313 dev_err(&client->dev,
314 "Failed to send power sequence (program start)\n");
315 return error;
316 }
317 msleep(FIRMWARE_ON_DELAY);
318
319 return 0;
320 }
321
zinitix_report_finger(struct bt541_ts_data * bt541,int slot,const struct point_coord * p)322 static void zinitix_report_finger(struct bt541_ts_data *bt541, int slot,
323 const struct point_coord *p)
324 {
325 u16 x, y;
326
327 if (unlikely(!(p->sub_status &
328 (SUB_BIT_UP | SUB_BIT_DOWN | SUB_BIT_MOVE)))) {
329 dev_dbg(&bt541->client->dev, "unknown finger event %#02x\n",
330 p->sub_status);
331 return;
332 }
333
334 x = le16_to_cpu(p->x);
335 y = le16_to_cpu(p->y);
336
337 input_mt_slot(bt541->input_dev, slot);
338 if (input_mt_report_slot_state(bt541->input_dev, MT_TOOL_FINGER,
339 !(p->sub_status & SUB_BIT_UP))) {
340 touchscreen_report_pos(bt541->input_dev,
341 &bt541->prop, x, y, true);
342 input_report_abs(bt541->input_dev,
343 ABS_MT_TOUCH_MAJOR, p->width);
344 dev_dbg(&bt541->client->dev, "finger %d %s (%u, %u)\n",
345 slot, p->sub_status & SUB_BIT_DOWN ? "down" : "move",
346 x, y);
347 } else {
348 dev_dbg(&bt541->client->dev, "finger %d up (%u, %u)\n",
349 slot, x, y);
350 }
351 }
352
zinitix_ts_irq_handler(int irq,void * bt541_handler)353 static irqreturn_t zinitix_ts_irq_handler(int irq, void *bt541_handler)
354 {
355 struct bt541_ts_data *bt541 = bt541_handler;
356 struct i2c_client *client = bt541->client;
357 struct touch_event touch_event;
358 unsigned long finger_mask;
359 int error;
360 int i;
361
362 memset(&touch_event, 0, sizeof(struct touch_event));
363
364 error = zinitix_read_data(bt541->client, ZINITIX_POINT_STATUS_REG,
365 &touch_event, sizeof(struct touch_event));
366 if (error) {
367 dev_err(&client->dev, "Failed to read in touchpoint struct\n");
368 goto out;
369 }
370
371 finger_mask = touch_event.finger_mask;
372 for_each_set_bit(i, &finger_mask, MAX_SUPPORTED_FINGER_NUM) {
373 const struct point_coord *p = &touch_event.point_coord[i];
374
375 /* Only process contacts that are actually reported */
376 if (p->sub_status & SUB_BIT_EXIST)
377 zinitix_report_finger(bt541, i, p);
378 }
379
380 input_mt_sync_frame(bt541->input_dev);
381 input_sync(bt541->input_dev);
382
383 out:
384 zinitix_write_cmd(bt541->client, ZINITIX_CLEAR_INT_STATUS_CMD);
385 return IRQ_HANDLED;
386 }
387
zinitix_start(struct bt541_ts_data * bt541)388 static int zinitix_start(struct bt541_ts_data *bt541)
389 {
390 int error;
391
392 error = regulator_bulk_enable(ARRAY_SIZE(bt541->supplies),
393 bt541->supplies);
394 if (error) {
395 dev_err(&bt541->client->dev,
396 "Failed to enable regulators: %d\n", error);
397 return error;
398 }
399
400 msleep(CHIP_ON_DELAY);
401
402 error = zinitix_send_power_on_sequence(bt541);
403 if (error) {
404 dev_err(&bt541->client->dev,
405 "Error while sending power-on sequence: %d\n", error);
406 return error;
407 }
408
409 error = zinitix_init_touch(bt541);
410 if (error) {
411 dev_err(&bt541->client->dev,
412 "Error while configuring touch IC\n");
413 return error;
414 }
415
416 enable_irq(bt541->client->irq);
417
418 return 0;
419 }
420
zinitix_stop(struct bt541_ts_data * bt541)421 static int zinitix_stop(struct bt541_ts_data *bt541)
422 {
423 int error;
424
425 disable_irq(bt541->client->irq);
426
427 error = regulator_bulk_disable(ARRAY_SIZE(bt541->supplies),
428 bt541->supplies);
429 if (error) {
430 dev_err(&bt541->client->dev,
431 "Failed to disable regulators: %d\n", error);
432 return error;
433 }
434
435 return 0;
436 }
437
zinitix_input_open(struct input_dev * dev)438 static int zinitix_input_open(struct input_dev *dev)
439 {
440 struct bt541_ts_data *bt541 = input_get_drvdata(dev);
441
442 return zinitix_start(bt541);
443 }
444
zinitix_input_close(struct input_dev * dev)445 static void zinitix_input_close(struct input_dev *dev)
446 {
447 struct bt541_ts_data *bt541 = input_get_drvdata(dev);
448
449 zinitix_stop(bt541);
450 }
451
zinitix_init_input_dev(struct bt541_ts_data * bt541)452 static int zinitix_init_input_dev(struct bt541_ts_data *bt541)
453 {
454 struct input_dev *input_dev;
455 int error;
456
457 input_dev = devm_input_allocate_device(&bt541->client->dev);
458 if (!input_dev) {
459 dev_err(&bt541->client->dev,
460 "Failed to allocate input device.");
461 return -ENOMEM;
462 }
463
464 input_set_drvdata(input_dev, bt541);
465 bt541->input_dev = input_dev;
466
467 input_dev->name = "Zinitix Capacitive TouchScreen";
468 input_dev->phys = "input/ts";
469 input_dev->id.bustype = BUS_I2C;
470 input_dev->open = zinitix_input_open;
471 input_dev->close = zinitix_input_close;
472
473 input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X);
474 input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y);
475 input_set_abs_params(input_dev, ABS_MT_WIDTH_MAJOR, 0, 255, 0, 0);
476 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
477
478 touchscreen_parse_properties(input_dev, true, &bt541->prop);
479 if (!bt541->prop.max_x || !bt541->prop.max_y) {
480 dev_err(&bt541->client->dev,
481 "Touchscreen-size-x and/or touchscreen-size-y not set in dts\n");
482 return -EINVAL;
483 }
484
485 error = input_mt_init_slots(input_dev, MAX_SUPPORTED_FINGER_NUM,
486 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
487 if (error) {
488 dev_err(&bt541->client->dev,
489 "Failed to initialize MT slots: %d", error);
490 return error;
491 }
492
493 error = input_register_device(input_dev);
494 if (error) {
495 dev_err(&bt541->client->dev,
496 "Failed to register input device: %d", error);
497 return error;
498 }
499
500 return 0;
501 }
502
zinitix_ts_probe(struct i2c_client * client)503 static int zinitix_ts_probe(struct i2c_client *client)
504 {
505 struct bt541_ts_data *bt541;
506 int error;
507
508 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
509 dev_err(&client->dev,
510 "Failed to assert adapter's support for plain I2C.\n");
511 return -ENXIO;
512 }
513
514 bt541 = devm_kzalloc(&client->dev, sizeof(*bt541), GFP_KERNEL);
515 if (!bt541)
516 return -ENOMEM;
517
518 bt541->client = client;
519 i2c_set_clientdata(client, bt541);
520
521 error = zinitix_init_regulators(bt541);
522 if (error) {
523 dev_err(&client->dev,
524 "Failed to initialize regulators: %d\n", error);
525 return error;
526 }
527
528 error = devm_request_threaded_irq(&client->dev, client->irq,
529 NULL, zinitix_ts_irq_handler,
530 IRQF_ONESHOT | IRQF_NO_AUTOEN,
531 client->name, bt541);
532 if (error) {
533 dev_err(&client->dev, "Failed to request IRQ: %d\n", error);
534 return error;
535 }
536
537 error = zinitix_init_input_dev(bt541);
538 if (error) {
539 dev_err(&client->dev,
540 "Failed to initialize input device: %d\n", error);
541 return error;
542 }
543
544 error = device_property_read_u32(&client->dev, "zinitix,mode",
545 &bt541->zinitix_mode);
546 if (error < 0) {
547 /* fall back to mode 2 */
548 bt541->zinitix_mode = DEFAULT_TOUCH_POINT_MODE;
549 }
550
551 if (bt541->zinitix_mode != 2) {
552 /*
553 * If there are devices that don't support mode 2, support
554 * for other modes (0, 1) will be needed.
555 */
556 dev_err(&client->dev,
557 "Malformed zinitix,mode property, must be 2 (supplied: %d)\n",
558 bt541->zinitix_mode);
559 return -EINVAL;
560 }
561
562 return 0;
563 }
564
zinitix_suspend(struct device * dev)565 static int zinitix_suspend(struct device *dev)
566 {
567 struct i2c_client *client = to_i2c_client(dev);
568 struct bt541_ts_data *bt541 = i2c_get_clientdata(client);
569
570 mutex_lock(&bt541->input_dev->mutex);
571
572 if (input_device_enabled(bt541->input_dev))
573 zinitix_stop(bt541);
574
575 mutex_unlock(&bt541->input_dev->mutex);
576
577 return 0;
578 }
579
zinitix_resume(struct device * dev)580 static int zinitix_resume(struct device *dev)
581 {
582 struct i2c_client *client = to_i2c_client(dev);
583 struct bt541_ts_data *bt541 = i2c_get_clientdata(client);
584 int ret = 0;
585
586 mutex_lock(&bt541->input_dev->mutex);
587
588 if (input_device_enabled(bt541->input_dev))
589 ret = zinitix_start(bt541);
590
591 mutex_unlock(&bt541->input_dev->mutex);
592
593 return ret;
594 }
595
596 static DEFINE_SIMPLE_DEV_PM_OPS(zinitix_pm_ops, zinitix_suspend, zinitix_resume);
597
598 #ifdef CONFIG_OF
599 static const struct of_device_id zinitix_of_match[] = {
600 { .compatible = "zinitix,bt402" },
601 { .compatible = "zinitix,bt403" },
602 { .compatible = "zinitix,bt404" },
603 { .compatible = "zinitix,bt412" },
604 { .compatible = "zinitix,bt413" },
605 { .compatible = "zinitix,bt431" },
606 { .compatible = "zinitix,bt432" },
607 { .compatible = "zinitix,bt531" },
608 { .compatible = "zinitix,bt532" },
609 { .compatible = "zinitix,bt538" },
610 { .compatible = "zinitix,bt541" },
611 { .compatible = "zinitix,bt548" },
612 { .compatible = "zinitix,bt554" },
613 { .compatible = "zinitix,at100" },
614 { }
615 };
616 MODULE_DEVICE_TABLE(of, zinitix_of_match);
617 #endif
618
619 static struct i2c_driver zinitix_ts_driver = {
620 .probe = zinitix_ts_probe,
621 .driver = {
622 .name = "Zinitix-TS",
623 .pm = pm_sleep_ptr(&zinitix_pm_ops),
624 .of_match_table = of_match_ptr(zinitix_of_match),
625 },
626 };
627 module_i2c_driver(zinitix_ts_driver);
628
629 MODULE_AUTHOR("Michael Srba <Michael.Srba@seznam.cz>");
630 MODULE_DESCRIPTION("Zinitix touchscreen driver");
631 MODULE_LICENSE("GPL v2");
632