1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2021 4 * Author(s): Giulio Benetti <giulio.benetti@benettiengineering.com> 5 */ 6 7 #include <linux/delay.h> 8 #include <linux/gpio/consumer.h> 9 #include <linux/i2c.h> 10 #include <linux/interrupt.h> 11 #include <linux/input.h> 12 #include <linux/input/mt.h> 13 #include <linux/input/touchscreen.h> 14 #include <linux/irq.h> 15 #include <linux/regulator/consumer.h> 16 #include <linux/regmap.h> 17 18 #include <linux/unaligned.h> 19 20 #define HY46XX_CHKSUM_CODE 0x1 21 #define HY46XX_FINGER_NUM 0x2 22 #define HY46XX_CHKSUM_LEN 0x7 23 #define HY46XX_THRESHOLD 0x80 24 #define HY46XX_GLOVE_EN 0x84 25 #define HY46XX_REPORT_SPEED 0x88 26 #define HY46XX_PWR_NOISE_EN 0x89 27 #define HY46XX_FILTER_DATA 0x8A 28 #define HY46XX_GAIN 0x92 29 #define HY46XX_EDGE_OFFSET 0x93 30 #define HY46XX_RX_NR_USED 0x94 31 #define HY46XX_TX_NR_USED 0x95 32 #define HY46XX_PWR_MODE 0xA5 33 #define HY46XX_FW_VERSION 0xA6 34 #define HY46XX_LIB_VERSION 0xA7 35 #define HY46XX_TP_INFO 0xA8 36 #define HY46XX_TP_CHIP_ID 0xA9 37 #define HY46XX_BOOT_VER 0xB0 38 39 #define HY46XX_TPLEN 0x6 40 #define HY46XX_REPORT_PKT_LEN 0x44 41 42 #define HY46XX_MAX_SUPPORTED_POINTS 11 43 44 #define TOUCH_EVENT_DOWN 0x00 45 #define TOUCH_EVENT_UP 0x01 46 #define TOUCH_EVENT_CONTACT 0x02 47 #define TOUCH_EVENT_RESERVED 0x03 48 49 struct hycon_hy46xx_data { 50 struct i2c_client *client; 51 struct input_dev *input; 52 struct touchscreen_properties prop; 53 struct regulator *vcc; 54 55 struct gpio_desc *reset_gpio; 56 57 struct mutex mutex; 58 struct regmap *regmap; 59 60 int threshold; 61 bool glove_enable; 62 int report_speed; 63 bool noise_filter_enable; 64 int filter_data; 65 int gain; 66 int edge_offset; 67 int rx_number_used; 68 int tx_number_used; 69 int power_mode; 70 int fw_version; 71 int lib_version; 72 int tp_information; 73 int tp_chip_id; 74 int bootloader_version; 75 }; 76 77 static const struct regmap_config hycon_hy46xx_i2c_regmap_config = { 78 .reg_bits = 8, 79 .val_bits = 8, 80 }; 81 82 static bool hycon_hy46xx_check_checksum(struct hycon_hy46xx_data *tsdata, u8 *buf) 83 { 84 u8 chksum = 0; 85 int i; 86 87 for (i = 2; i < buf[HY46XX_CHKSUM_LEN]; i++) 88 chksum += buf[i]; 89 90 if (chksum == buf[HY46XX_CHKSUM_CODE]) 91 return true; 92 93 dev_err_ratelimited(&tsdata->client->dev, 94 "checksum error: 0x%02x expected, got 0x%02x\n", 95 chksum, buf[HY46XX_CHKSUM_CODE]); 96 97 return false; 98 } 99 100 static irqreturn_t hycon_hy46xx_isr(int irq, void *dev_id) 101 { 102 struct hycon_hy46xx_data *tsdata = dev_id; 103 struct device *dev = &tsdata->client->dev; 104 u8 rdbuf[HY46XX_REPORT_PKT_LEN]; 105 int i, x, y, id; 106 int error; 107 108 memset(rdbuf, 0, sizeof(rdbuf)); 109 110 error = regmap_bulk_read(tsdata->regmap, 0, rdbuf, sizeof(rdbuf)); 111 if (error) { 112 dev_err_ratelimited(dev, "Unable to fetch data, error: %d\n", 113 error); 114 goto out; 115 } 116 117 if (!hycon_hy46xx_check_checksum(tsdata, rdbuf)) 118 goto out; 119 120 for (i = 0; i < HY46XX_MAX_SUPPORTED_POINTS; i++) { 121 u8 *buf = &rdbuf[3 + (HY46XX_TPLEN * i)]; 122 int type = buf[0] >> 6; 123 124 if (type == TOUCH_EVENT_RESERVED) 125 continue; 126 127 x = get_unaligned_be16(buf) & 0x0fff; 128 y = get_unaligned_be16(buf + 2) & 0x0fff; 129 130 id = buf[2] >> 4; 131 132 input_mt_slot(tsdata->input, id); 133 if (input_mt_report_slot_state(tsdata->input, MT_TOOL_FINGER, 134 type != TOUCH_EVENT_UP)) 135 touchscreen_report_pos(tsdata->input, &tsdata->prop, 136 x, y, true); 137 } 138 139 input_mt_report_pointer_emulation(tsdata->input, false); 140 input_sync(tsdata->input); 141 142 out: 143 return IRQ_HANDLED; 144 } 145 146 struct hycon_hy46xx_attribute { 147 struct device_attribute dattr; 148 size_t field_offset; 149 u8 address; 150 u8 limit_low; 151 u8 limit_high; 152 }; 153 154 #define HYCON_ATTR_U8(_field, _mode, _address, _limit_low, _limit_high) \ 155 struct hycon_hy46xx_attribute hycon_hy46xx_attr_##_field = { \ 156 .dattr = __ATTR(_field, _mode, \ 157 hycon_hy46xx_setting_show, \ 158 hycon_hy46xx_setting_store), \ 159 .field_offset = offsetof(struct hycon_hy46xx_data, _field), \ 160 .address = _address, \ 161 .limit_low = _limit_low, \ 162 .limit_high = _limit_high, \ 163 } 164 165 #define HYCON_ATTR_BOOL(_field, _mode, _address) \ 166 struct hycon_hy46xx_attribute hycon_hy46xx_attr_##_field = { \ 167 .dattr = __ATTR(_field, _mode, \ 168 hycon_hy46xx_setting_show, \ 169 hycon_hy46xx_setting_store), \ 170 .field_offset = offsetof(struct hycon_hy46xx_data, _field), \ 171 .address = _address, \ 172 .limit_low = false, \ 173 .limit_high = true, \ 174 } 175 176 static ssize_t hycon_hy46xx_setting_show(struct device *dev, 177 struct device_attribute *dattr, char *buf) 178 { 179 struct i2c_client *client = to_i2c_client(dev); 180 struct hycon_hy46xx_data *tsdata = i2c_get_clientdata(client); 181 struct hycon_hy46xx_attribute *attr = 182 container_of(dattr, struct hycon_hy46xx_attribute, dattr); 183 u8 *field = (u8 *)tsdata + attr->field_offset; 184 int error = 0; 185 int val; 186 187 guard(mutex)(&tsdata->mutex); 188 189 error = regmap_read(tsdata->regmap, attr->address, &val); 190 if (error) { 191 dev_err(&tsdata->client->dev, 192 "Failed to fetch attribute %s, error %d\n", 193 dattr->attr.name, error); 194 return error; 195 } 196 197 if (val != *field) { 198 dev_warn(&tsdata->client->dev, 199 "%s: read (%d) and stored value (%d) differ\n", 200 dattr->attr.name, val, *field); 201 *field = val; 202 } 203 204 return sysfs_emit(buf, "%d\n", val); 205 } 206 207 static ssize_t hycon_hy46xx_setting_store(struct device *dev, 208 struct device_attribute *dattr, 209 const char *buf, size_t count) 210 { 211 struct i2c_client *client = to_i2c_client(dev); 212 struct hycon_hy46xx_data *tsdata = i2c_get_clientdata(client); 213 struct hycon_hy46xx_attribute *attr = 214 container_of(dattr, struct hycon_hy46xx_attribute, dattr); 215 u8 *field = (u8 *)tsdata + attr->field_offset; 216 unsigned int val; 217 int error; 218 219 guard(mutex)(&tsdata->mutex); 220 221 error = kstrtouint(buf, 0, &val); 222 if (error) 223 return error; 224 225 if (val < attr->limit_low || val > attr->limit_high) 226 return -ERANGE; 227 228 error = regmap_write(tsdata->regmap, attr->address, val); 229 if (error) { 230 dev_err(&tsdata->client->dev, 231 "Failed to update attribute %s, error: %d\n", 232 dattr->attr.name, error); 233 return error; 234 } 235 *field = val; 236 237 return count; 238 } 239 240 static HYCON_ATTR_U8(threshold, 0644, HY46XX_THRESHOLD, 0, 255); 241 static HYCON_ATTR_BOOL(glove_enable, 0644, HY46XX_GLOVE_EN); 242 static HYCON_ATTR_U8(report_speed, 0644, HY46XX_REPORT_SPEED, 0, 255); 243 static HYCON_ATTR_BOOL(noise_filter_enable, 0644, HY46XX_PWR_NOISE_EN); 244 static HYCON_ATTR_U8(filter_data, 0644, HY46XX_FILTER_DATA, 0, 5); 245 static HYCON_ATTR_U8(gain, 0644, HY46XX_GAIN, 0, 5); 246 static HYCON_ATTR_U8(edge_offset, 0644, HY46XX_EDGE_OFFSET, 0, 5); 247 static HYCON_ATTR_U8(fw_version, 0444, HY46XX_FW_VERSION, 0, 255); 248 static HYCON_ATTR_U8(lib_version, 0444, HY46XX_LIB_VERSION, 0, 255); 249 static HYCON_ATTR_U8(tp_information, 0444, HY46XX_TP_INFO, 0, 255); 250 static HYCON_ATTR_U8(tp_chip_id, 0444, HY46XX_TP_CHIP_ID, 0, 255); 251 static HYCON_ATTR_U8(bootloader_version, 0444, HY46XX_BOOT_VER, 0, 255); 252 253 static struct attribute *hycon_hy46xx_attrs[] = { 254 &hycon_hy46xx_attr_threshold.dattr.attr, 255 &hycon_hy46xx_attr_glove_enable.dattr.attr, 256 &hycon_hy46xx_attr_report_speed.dattr.attr, 257 &hycon_hy46xx_attr_noise_filter_enable.dattr.attr, 258 &hycon_hy46xx_attr_filter_data.dattr.attr, 259 &hycon_hy46xx_attr_gain.dattr.attr, 260 &hycon_hy46xx_attr_edge_offset.dattr.attr, 261 &hycon_hy46xx_attr_fw_version.dattr.attr, 262 &hycon_hy46xx_attr_lib_version.dattr.attr, 263 &hycon_hy46xx_attr_tp_information.dattr.attr, 264 &hycon_hy46xx_attr_tp_chip_id.dattr.attr, 265 &hycon_hy46xx_attr_bootloader_version.dattr.attr, 266 NULL 267 }; 268 ATTRIBUTE_GROUPS(hycon_hy46xx); 269 270 static void hycon_hy46xx_get_defaults(struct device *dev, struct hycon_hy46xx_data *tsdata) 271 { 272 bool val_bool; 273 int error; 274 u32 val; 275 276 error = device_property_read_u32(dev, "hycon,threshold", &val); 277 if (!error) { 278 error = regmap_write(tsdata->regmap, HY46XX_THRESHOLD, val); 279 if (error < 0) 280 goto out; 281 282 tsdata->threshold = val; 283 } 284 285 val_bool = device_property_read_bool(dev, "hycon,glove-enable"); 286 error = regmap_write(tsdata->regmap, HY46XX_GLOVE_EN, val_bool); 287 if (error < 0) 288 goto out; 289 tsdata->glove_enable = val_bool; 290 291 error = device_property_read_u32(dev, "hycon,report-speed-hz", &val); 292 if (!error) { 293 error = regmap_write(tsdata->regmap, HY46XX_REPORT_SPEED, val); 294 if (error < 0) 295 goto out; 296 297 tsdata->report_speed = val; 298 } 299 300 val_bool = device_property_read_bool(dev, "hycon,noise-filter-enable"); 301 error = regmap_write(tsdata->regmap, HY46XX_PWR_NOISE_EN, val_bool); 302 if (error < 0) 303 goto out; 304 tsdata->noise_filter_enable = val_bool; 305 306 error = device_property_read_u32(dev, "hycon,filter-data", &val); 307 if (!error) { 308 error = regmap_write(tsdata->regmap, HY46XX_FILTER_DATA, val); 309 if (error < 0) 310 goto out; 311 312 tsdata->filter_data = val; 313 } 314 315 error = device_property_read_u32(dev, "hycon,gain", &val); 316 if (!error) { 317 error = regmap_write(tsdata->regmap, HY46XX_GAIN, val); 318 if (error < 0) 319 goto out; 320 321 tsdata->gain = val; 322 } 323 324 error = device_property_read_u32(dev, "hycon,edge-offset", &val); 325 if (!error) { 326 error = regmap_write(tsdata->regmap, HY46XX_EDGE_OFFSET, val); 327 if (error < 0) 328 goto out; 329 330 tsdata->edge_offset = val; 331 } 332 333 return; 334 out: 335 dev_err(&tsdata->client->dev, "Failed to set default settings"); 336 } 337 338 static void hycon_hy46xx_get_parameters(struct hycon_hy46xx_data *tsdata) 339 { 340 int error; 341 u32 val; 342 343 error = regmap_read(tsdata->regmap, HY46XX_THRESHOLD, &val); 344 if (error < 0) 345 goto out; 346 tsdata->threshold = val; 347 348 error = regmap_read(tsdata->regmap, HY46XX_GLOVE_EN, &val); 349 if (error < 0) 350 goto out; 351 tsdata->glove_enable = val; 352 353 error = regmap_read(tsdata->regmap, HY46XX_REPORT_SPEED, &val); 354 if (error < 0) 355 goto out; 356 tsdata->report_speed = val; 357 358 error = regmap_read(tsdata->regmap, HY46XX_PWR_NOISE_EN, &val); 359 if (error < 0) 360 goto out; 361 tsdata->noise_filter_enable = val; 362 363 error = regmap_read(tsdata->regmap, HY46XX_FILTER_DATA, &val); 364 if (error < 0) 365 goto out; 366 tsdata->filter_data = val; 367 368 error = regmap_read(tsdata->regmap, HY46XX_GAIN, &val); 369 if (error < 0) 370 goto out; 371 tsdata->gain = val; 372 373 error = regmap_read(tsdata->regmap, HY46XX_EDGE_OFFSET, &val); 374 if (error < 0) 375 goto out; 376 tsdata->edge_offset = val; 377 378 error = regmap_read(tsdata->regmap, HY46XX_RX_NR_USED, &val); 379 if (error < 0) 380 goto out; 381 tsdata->rx_number_used = val; 382 383 error = regmap_read(tsdata->regmap, HY46XX_TX_NR_USED, &val); 384 if (error < 0) 385 goto out; 386 tsdata->tx_number_used = val; 387 388 error = regmap_read(tsdata->regmap, HY46XX_PWR_MODE, &val); 389 if (error < 0) 390 goto out; 391 tsdata->power_mode = val; 392 393 error = regmap_read(tsdata->regmap, HY46XX_FW_VERSION, &val); 394 if (error < 0) 395 goto out; 396 tsdata->fw_version = val; 397 398 error = regmap_read(tsdata->regmap, HY46XX_LIB_VERSION, &val); 399 if (error < 0) 400 goto out; 401 tsdata->lib_version = val; 402 403 error = regmap_read(tsdata->regmap, HY46XX_TP_INFO, &val); 404 if (error < 0) 405 goto out; 406 tsdata->tp_information = val; 407 408 error = regmap_read(tsdata->regmap, HY46XX_TP_CHIP_ID, &val); 409 if (error < 0) 410 goto out; 411 tsdata->tp_chip_id = val; 412 413 error = regmap_read(tsdata->regmap, HY46XX_BOOT_VER, &val); 414 if (error < 0) 415 goto out; 416 tsdata->bootloader_version = val; 417 418 return; 419 out: 420 dev_err(&tsdata->client->dev, "Failed to read default settings"); 421 } 422 423 static void hycon_hy46xx_disable_regulator(void *arg) 424 { 425 struct hycon_hy46xx_data *data = arg; 426 427 regulator_disable(data->vcc); 428 } 429 430 static int hycon_hy46xx_probe(struct i2c_client *client) 431 { 432 struct hycon_hy46xx_data *tsdata; 433 struct input_dev *input; 434 int error; 435 436 dev_dbg(&client->dev, "probing for HYCON HY46XX I2C\n"); 437 438 tsdata = devm_kzalloc(&client->dev, sizeof(*tsdata), GFP_KERNEL); 439 if (!tsdata) 440 return -ENOMEM; 441 442 tsdata->vcc = devm_regulator_get(&client->dev, "vcc"); 443 if (IS_ERR(tsdata->vcc)) { 444 error = PTR_ERR(tsdata->vcc); 445 if (error != -EPROBE_DEFER) 446 dev_err(&client->dev, 447 "failed to request regulator: %d\n", error); 448 return error; 449 } 450 451 error = regulator_enable(tsdata->vcc); 452 if (error < 0) { 453 dev_err(&client->dev, "failed to enable vcc: %d\n", error); 454 return error; 455 } 456 457 error = devm_add_action_or_reset(&client->dev, 458 hycon_hy46xx_disable_regulator, 459 tsdata); 460 if (error) 461 return error; 462 463 tsdata->reset_gpio = devm_gpiod_get_optional(&client->dev, 464 "reset", GPIOD_OUT_LOW); 465 if (IS_ERR(tsdata->reset_gpio)) { 466 error = PTR_ERR(tsdata->reset_gpio); 467 dev_err(&client->dev, 468 "Failed to request GPIO reset pin, error %d\n", error); 469 return error; 470 } 471 472 if (tsdata->reset_gpio) { 473 usleep_range(5000, 6000); 474 gpiod_set_value_cansleep(tsdata->reset_gpio, 1); 475 usleep_range(5000, 6000); 476 gpiod_set_value_cansleep(tsdata->reset_gpio, 0); 477 msleep(1000); 478 } 479 480 input = devm_input_allocate_device(&client->dev); 481 if (!input) { 482 dev_err(&client->dev, "failed to allocate input device.\n"); 483 return -ENOMEM; 484 } 485 486 mutex_init(&tsdata->mutex); 487 tsdata->client = client; 488 tsdata->input = input; 489 490 tsdata->regmap = devm_regmap_init_i2c(client, 491 &hycon_hy46xx_i2c_regmap_config); 492 if (IS_ERR(tsdata->regmap)) { 493 dev_err(&client->dev, "regmap allocation failed\n"); 494 return PTR_ERR(tsdata->regmap); 495 } 496 497 hycon_hy46xx_get_defaults(&client->dev, tsdata); 498 hycon_hy46xx_get_parameters(tsdata); 499 500 input->name = "Hycon Capacitive Touch"; 501 input->id.bustype = BUS_I2C; 502 input->dev.parent = &client->dev; 503 504 input_set_abs_params(input, ABS_MT_POSITION_X, 0, -1, 0, 0); 505 input_set_abs_params(input, ABS_MT_POSITION_Y, 0, -1, 0, 0); 506 507 touchscreen_parse_properties(input, true, &tsdata->prop); 508 509 error = input_mt_init_slots(input, HY46XX_MAX_SUPPORTED_POINTS, 510 INPUT_MT_DIRECT); 511 if (error) { 512 dev_err(&client->dev, "Unable to init MT slots.\n"); 513 return error; 514 } 515 516 i2c_set_clientdata(client, tsdata); 517 518 error = devm_request_threaded_irq(&client->dev, client->irq, 519 NULL, hycon_hy46xx_isr, IRQF_ONESHOT, 520 client->name, tsdata); 521 if (error) { 522 dev_err(&client->dev, "Unable to request touchscreen IRQ.\n"); 523 return error; 524 } 525 526 error = input_register_device(input); 527 if (error) 528 return error; 529 530 dev_dbg(&client->dev, 531 "HYCON HY46XX initialized: IRQ %d, Reset pin %d.\n", 532 client->irq, 533 tsdata->reset_gpio ? desc_to_gpio(tsdata->reset_gpio) : -1); 534 535 return 0; 536 } 537 538 static const struct i2c_device_id hycon_hy46xx_id[] = { 539 { .name = "hy4613" }, 540 { .name = "hy4614" }, 541 { .name = "hy4621" }, 542 { .name = "hy4623" }, 543 { .name = "hy4633" }, 544 { .name = "hy4635" }, 545 { /* sentinel */ } 546 }; 547 MODULE_DEVICE_TABLE(i2c, hycon_hy46xx_id); 548 549 static const struct of_device_id hycon_hy46xx_of_match[] = { 550 { .compatible = "hycon,hy4613" }, 551 { .compatible = "hycon,hy4614" }, 552 { .compatible = "hycon,hy4621" }, 553 { .compatible = "hycon,hy4623" }, 554 { .compatible = "hycon,hy4633" }, 555 { .compatible = "hycon,hy4635" }, 556 { /* sentinel */ } 557 }; 558 MODULE_DEVICE_TABLE(of, hycon_hy46xx_of_match); 559 560 static struct i2c_driver hycon_hy46xx_driver = { 561 .driver = { 562 .name = "hycon_hy46xx", 563 .dev_groups = hycon_hy46xx_groups, 564 .of_match_table = hycon_hy46xx_of_match, 565 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 566 }, 567 .id_table = hycon_hy46xx_id, 568 .probe = hycon_hy46xx_probe, 569 }; 570 571 module_i2c_driver(hycon_hy46xx_driver); 572 573 MODULE_AUTHOR("Giulio Benetti <giulio.benetti@benettiengineering.com>"); 574 MODULE_DESCRIPTION("HYCON HY46XX I2C Touchscreen Driver"); 575 MODULE_LICENSE("GPL v2"); 576