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 BT541_SWRESET_CMD 0x0000 19#define BT541_WAKEUP_CMD 0x0001 20 21#define BT541_IDLE_CMD 0x0004 22#define BT541_SLEEP_CMD 0x0005 23 24#define BT541_CLEAR_INT_STATUS_CMD 0x0003 25#define BT541_CALIBRATE_CMD 0x0006 26#define BT541_SAVE_STATUS_CMD 0x0007 27#define BT541_SAVE_CALIBRATION_CMD 0x0008 28#define BT541_RECALL_FACTORY_CMD 0x000f 29 30#define BT541_THRESHOLD 0x0020 31 32#define BT541_LARGE_PALM_REJECT_AREA_TH 0x003F 33 34#define BT541_DEBUG_REG 0x0115 /* 0~7 */ 35 36#define BT541_TOUCH_MODE 0x0010 37#define BT541_CHIP_REVISION 0x0011 38#define BT541_FIRMWARE_VERSION 0x0012 39 40#define ZINITIX_USB_DETECT 0x116 41 42#define BT541_MINOR_FW_VERSION 0x0121 43 44#define BT541_VENDOR_ID 0x001C 45#define BT541_HW_ID 0x0014 46 47#define BT541_DATA_VERSION_REG 0x0013 48#define BT541_SUPPORTED_FINGER_NUM 0x0015 49#define BT541_EEPROM_INFO 0x0018 50#define BT541_INITIAL_TOUCH_MODE 0x0019 51 52#define BT541_TOTAL_NUMBER_OF_X 0x0060 53#define BT541_TOTAL_NUMBER_OF_Y 0x0061 54 55#define BT541_DELAY_RAW_FOR_HOST 0x007f 56 57#define BT541_BUTTON_SUPPORTED_NUM 0x00B0 58#define BT541_BUTTON_SENSITIVITY 0x00B2 59#define BT541_DUMMY_BUTTON_SENSITIVITY 0X00C8 60 61#define BT541_X_RESOLUTION 0x00C0 62#define BT541_Y_RESOLUTION 0x00C1 63 64#define BT541_POINT_STATUS_REG 0x0080 65#define BT541_ICON_STATUS_REG 0x00AA 66 67#define BT541_POINT_COORD_REG (BT541_POINT_STATUS_REG + 2) 68 69#define BT541_AFE_FREQUENCY 0x0100 70#define BT541_DND_N_COUNT 0x0122 71#define BT541_DND_U_COUNT 0x0135 72 73#define BT541_RAWDATA_REG 0x0200 74 75#define BT541_EEPROM_INFO_REG 0x0018 76 77#define BT541_INT_ENABLE_FLAG 0x00f0 78#define BT541_PERIODICAL_INTERRUPT_INTERVAL 0x00f1 79 80#define BT541_BTN_WIDTH 0x016d 81 82#define BT541_CHECKSUM_RESULT 0x012c 83 84#define BT541_INIT_FLASH 0x01d0 85#define BT541_WRITE_FLASH 0x01d1 86#define BT541_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 126struct 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 136struct 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 143struct 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 151static 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 169static 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 181static 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 193static 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, BT541_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, BT541_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, BT541_X_RESOLUTION, 214 bt541->prop.max_x); 215 if (error) 216 return error; 217 218 error = zinitix_write_u16(client, BT541_Y_RESOLUTION, 219 bt541->prop.max_y); 220 if (error) 221 return error; 222 223 error = zinitix_write_u16(client, BT541_SUPPORTED_FINGER_NUM, 224 MAX_SUPPORTED_FINGER_NUM); 225 if (error) 226 return error; 227 228 error = zinitix_write_u16(client, BT541_INITIAL_TOUCH_MODE, 229 bt541->zinitix_mode); 230 if (error) 231 return error; 232 233 error = zinitix_write_u16(client, BT541_TOUCH_MODE, 234 bt541->zinitix_mode); 235 if (error) 236 return error; 237 238 error = zinitix_write_u16(client, BT541_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, BT541_CLEAR_INT_STATUS_CMD); 247 udelay(10); 248 } 249 250 return 0; 251} 252 253static int zinitix_init_regulators(struct bt541_ts_data *bt541) 254{ 255 struct i2c_client *client = bt541->client; 256 int error; 257 258 bt541->supplies[0].supply = "vdd"; 259 bt541->supplies[1].supply = "vddo"; 260 error = devm_regulator_bulk_get(&client->dev, 261 ARRAY_SIZE(bt541->supplies), 262 bt541->supplies); 263 if (error < 0) { 264 dev_err(&client->dev, "Failed to get regulators: %d\n", error); 265 return error; 266 } 267 268 return 0; 269} 270 271static int zinitix_send_power_on_sequence(struct bt541_ts_data *bt541) 272{ 273 int error; 274 struct i2c_client *client = bt541->client; 275 276 error = zinitix_write_u16(client, 0xc000, 0x0001); 277 if (error) { 278 dev_err(&client->dev, 279 "Failed to send power sequence(vendor cmd enable)\n"); 280 return error; 281 } 282 udelay(10); 283 284 error = zinitix_write_cmd(client, 0xc004); 285 if (error) { 286 dev_err(&client->dev, 287 "Failed to send power sequence (intn clear)\n"); 288 return error; 289 } 290 udelay(10); 291 292 error = zinitix_write_u16(client, 0xc002, 0x0001); 293 if (error) { 294 dev_err(&client->dev, 295 "Failed to send power sequence (nvm init)\n"); 296 return error; 297 } 298 mdelay(2); 299 300 error = zinitix_write_u16(client, 0xc001, 0x0001); 301 if (error) { 302 dev_err(&client->dev, 303 "Failed to send power sequence (program start)\n"); 304 return error; 305 } 306 msleep(FIRMWARE_ON_DELAY); 307 308 return 0; 309} 310 311static void zinitix_report_finger(struct bt541_ts_data *bt541, int slot, 312 const struct point_coord *p) 313{ 314 u16 x, y; 315 316 if (unlikely(!(p->sub_status & 317 (SUB_BIT_UP | SUB_BIT_DOWN | SUB_BIT_MOVE)))) { 318 dev_dbg(&bt541->client->dev, "unknown finger event %#02x\n", 319 p->sub_status); 320 return; 321 } 322 323 x = le16_to_cpu(p->x); 324 y = le16_to_cpu(p->y); 325 326 input_mt_slot(bt541->input_dev, slot); 327 if (input_mt_report_slot_state(bt541->input_dev, MT_TOOL_FINGER, 328 !(p->sub_status & SUB_BIT_UP))) { 329 touchscreen_report_pos(bt541->input_dev, 330 &bt541->prop, x, y, true); 331 input_report_abs(bt541->input_dev, 332 ABS_MT_TOUCH_MAJOR, p->width); 333 dev_dbg(&bt541->client->dev, "finger %d %s (%u, %u)\n", 334 slot, p->sub_status & SUB_BIT_DOWN ? "down" : "move", 335 x, y); 336 } else { 337 dev_dbg(&bt541->client->dev, "finger %d up (%u, %u)\n", 338 slot, x, y); 339 } 340} 341 342static irqreturn_t zinitix_ts_irq_handler(int irq, void *bt541_handler) 343{ 344 struct bt541_ts_data *bt541 = bt541_handler; 345 struct i2c_client *client = bt541->client; 346 struct touch_event touch_event; 347 unsigned long finger_mask; 348 int error; 349 int i; 350 351 memset(&touch_event, 0, sizeof(struct touch_event)); 352 353 error = zinitix_read_data(bt541->client, BT541_POINT_STATUS_REG, 354 &touch_event, sizeof(struct touch_event)); 355 if (error) { 356 dev_err(&client->dev, "Failed to read in touchpoint struct\n"); 357 goto out; 358 } 359 360 finger_mask = touch_event.finger_mask; 361 for_each_set_bit(i, &finger_mask, MAX_SUPPORTED_FINGER_NUM) { 362 const struct point_coord *p = &touch_event.point_coord[i]; 363 364 /* Only process contacts that are actually reported */ 365 if (p->sub_status & SUB_BIT_EXIST) 366 zinitix_report_finger(bt541, i, p); 367 } 368 369 input_mt_sync_frame(bt541->input_dev); 370 input_sync(bt541->input_dev); 371 372out: 373 zinitix_write_cmd(bt541->client, BT541_CLEAR_INT_STATUS_CMD); 374 return IRQ_HANDLED; 375} 376 377static int zinitix_start(struct bt541_ts_data *bt541) 378{ 379 int error; 380 381 error = regulator_bulk_enable(ARRAY_SIZE(bt541->supplies), 382 bt541->supplies); 383 if (error) { 384 dev_err(&bt541->client->dev, 385 "Failed to enable regulators: %d\n", error); 386 return error; 387 } 388 389 msleep(CHIP_ON_DELAY); 390 391 error = zinitix_send_power_on_sequence(bt541); 392 if (error) { 393 dev_err(&bt541->client->dev, 394 "Error while sending power-on sequence: %d\n", error); 395 return error; 396 } 397 398 error = zinitix_init_touch(bt541); 399 if (error) { 400 dev_err(&bt541->client->dev, 401 "Error while configuring touch IC\n"); 402 return error; 403 } 404 405 enable_irq(bt541->client->irq); 406 407 return 0; 408} 409 410static int zinitix_stop(struct bt541_ts_data *bt541) 411{ 412 int error; 413 414 disable_irq(bt541->client->irq); 415 416 error = regulator_bulk_disable(ARRAY_SIZE(bt541->supplies), 417 bt541->supplies); 418 if (error) { 419 dev_err(&bt541->client->dev, 420 "Failed to disable regulators: %d\n", error); 421 return error; 422 } 423 424 return 0; 425} 426 427static int zinitix_input_open(struct input_dev *dev) 428{ 429 struct bt541_ts_data *bt541 = input_get_drvdata(dev); 430 431 return zinitix_start(bt541); 432} 433 434static void zinitix_input_close(struct input_dev *dev) 435{ 436 struct bt541_ts_data *bt541 = input_get_drvdata(dev); 437 438 zinitix_stop(bt541); 439} 440 441static int zinitix_init_input_dev(struct bt541_ts_data *bt541) 442{ 443 struct input_dev *input_dev; 444 int error; 445 446 input_dev = devm_input_allocate_device(&bt541->client->dev); 447 if (!input_dev) { 448 dev_err(&bt541->client->dev, 449 "Failed to allocate input device."); 450 return -ENOMEM; 451 } 452 453 input_set_drvdata(input_dev, bt541); 454 bt541->input_dev = input_dev; 455 456 input_dev->name = "Zinitix Capacitive TouchScreen"; 457 input_dev->phys = "input/ts"; 458 input_dev->id.bustype = BUS_I2C; 459 input_dev->open = zinitix_input_open; 460 input_dev->close = zinitix_input_close; 461 462 input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X); 463 input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y); 464 input_set_abs_params(input_dev, ABS_MT_WIDTH_MAJOR, 0, 255, 0, 0); 465 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0); 466 467 touchscreen_parse_properties(input_dev, true, &bt541->prop); 468 if (!bt541->prop.max_x || !bt541->prop.max_y) { 469 dev_err(&bt541->client->dev, 470 "Touchscreen-size-x and/or touchscreen-size-y not set in dts\n"); 471 return -EINVAL; 472 } 473 474 error = input_mt_init_slots(input_dev, MAX_SUPPORTED_FINGER_NUM, 475 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); 476 if (error) { 477 dev_err(&bt541->client->dev, 478 "Failed to initialize MT slots: %d", error); 479 return error; 480 } 481 482 error = input_register_device(input_dev); 483 if (error) { 484 dev_err(&bt541->client->dev, 485 "Failed to register input device: %d", error); 486 return error; 487 } 488 489 return 0; 490} 491 492static int zinitix_ts_probe(struct i2c_client *client) 493{ 494 struct bt541_ts_data *bt541; 495 int error; 496 497 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { 498 dev_err(&client->dev, 499 "Failed to assert adapter's support for plain I2C.\n"); 500 return -ENXIO; 501 } 502 503 bt541 = devm_kzalloc(&client->dev, sizeof(*bt541), GFP_KERNEL); 504 if (!bt541) 505 return -ENOMEM; 506 507 bt541->client = client; 508 i2c_set_clientdata(client, bt541); 509 510 error = zinitix_init_regulators(bt541); 511 if (error) { 512 dev_err(&client->dev, 513 "Failed to initialize regulators: %d\n", error); 514 return error; 515 } 516 517 error = devm_request_threaded_irq(&client->dev, client->irq, 518 NULL, zinitix_ts_irq_handler, 519 IRQF_ONESHOT, 520 client->name, bt541); 521 if (error) { 522 dev_err(&client->dev, "Failed to request IRQ: %d\n", error); 523 return error; 524 } 525 526 error = zinitix_init_input_dev(bt541); 527 if (error) { 528 dev_err(&client->dev, 529 "Failed to initialize input device: %d\n", error); 530 return error; 531 } 532 533 error = device_property_read_u32(&client->dev, "zinitix,mode", 534 &bt541->zinitix_mode); 535 if (error < 0) { 536 /* fall back to mode 2 */ 537 bt541->zinitix_mode = DEFAULT_TOUCH_POINT_MODE; 538 } 539 540 if (bt541->zinitix_mode != 2) { 541 /* 542 * If there are devices that don't support mode 2, support 543 * for other modes (0, 1) will be needed. 544 */ 545 dev_err(&client->dev, 546 "Malformed zinitix,mode property, must be 2 (supplied: %d)\n", 547 bt541->zinitix_mode); 548 return -EINVAL; 549 } 550 551 irq_set_status_flags(client->irq, IRQ_NOAUTOEN); 552 553 return 0; 554} 555 556static int __maybe_unused zinitix_suspend(struct device *dev) 557{ 558 struct i2c_client *client = to_i2c_client(dev); 559 struct bt541_ts_data *bt541 = i2c_get_clientdata(client); 560 561 mutex_lock(&bt541->input_dev->mutex); 562 563 if (bt541->input_dev->users) 564 zinitix_stop(bt541); 565 566 mutex_unlock(&bt541->input_dev->mutex); 567 568 return 0; 569} 570 571static int __maybe_unused zinitix_resume(struct device *dev) 572{ 573 struct i2c_client *client = to_i2c_client(dev); 574 struct bt541_ts_data *bt541 = i2c_get_clientdata(client); 575 int ret = 0; 576 577 mutex_lock(&bt541->input_dev->mutex); 578 579 if (bt541->input_dev->users) 580 ret = zinitix_start(bt541); 581 582 mutex_unlock(&bt541->input_dev->mutex); 583 584 return ret; 585} 586 587static SIMPLE_DEV_PM_OPS(zinitix_pm_ops, zinitix_suspend, zinitix_resume); 588 589#ifdef CONFIG_OF 590static const struct of_device_id zinitix_of_match[] = { 591 { .compatible = "zinitix,bt541" }, 592 { } 593}; 594MODULE_DEVICE_TABLE(of, zinitix_of_match); 595#endif 596 597static struct i2c_driver zinitix_ts_driver = { 598 .probe_new = zinitix_ts_probe, 599 .driver = { 600 .name = "Zinitix-TS", 601 .pm = &zinitix_pm_ops, 602 .of_match_table = of_match_ptr(zinitix_of_match), 603 }, 604}; 605module_i2c_driver(zinitix_ts_driver); 606 607MODULE_AUTHOR("Michael Srba <Michael.Srba@seznam.cz>"); 608MODULE_DESCRIPTION("Zinitix touchscreen driver"); 609MODULE_LICENSE("GPL v2"); 610