1 /* 2 * HID Driver for ELAN Touchpad 3 * 4 * Currently only supports touchpad found on HP Pavilion X2 10 5 * 6 * Copyright (c) 2016 Alexandrov Stanislav <neko@nya.ai> 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License as published by the Free 10 * Software Foundation; either version 2 of the License, or (at your option) 11 * any later version. 12 */ 13 14 #include <linux/hid.h> 15 #include <linux/input/mt.h> 16 #include <linux/leds.h> 17 #include <linux/module.h> 18 #include <linux/usb.h> 19 20 #include "hid-ids.h" 21 22 #define ELAN_MT_I2C 0x5d 23 #define ELAN_SINGLE_FINGER 0x81 24 #define ELAN_MT_FIRST_FINGER 0x82 25 #define ELAN_MT_SECOND_FINGER 0x83 26 #define ELAN_INPUT_REPORT_SIZE 8 27 #define ELAN_I2C_REPORT_SIZE 32 28 #define ELAN_FINGER_DATA_LEN 5 29 #define ELAN_MAX_FINGERS 5 30 #define ELAN_MAX_PRESSURE 255 31 #define ELAN_TP_USB_INTF 1 32 33 #define ELAN_FEATURE_REPORT 0x0d 34 #define ELAN_FEATURE_SIZE 5 35 #define ELAN_PARAM_MAX_X 6 36 #define ELAN_PARAM_MAX_Y 7 37 #define ELAN_PARAM_RES 8 38 39 #define ELAN_MUTE_LED_REPORT 0xBC 40 #define ELAN_LED_REPORT_SIZE 8 41 42 #define ELAN_HAS_LED BIT(0) 43 44 struct elan_drvdata { 45 struct input_dev *input; 46 u8 prev_report[ELAN_INPUT_REPORT_SIZE]; 47 struct led_classdev mute_led; 48 u8 mute_led_state; 49 u16 max_x; 50 u16 max_y; 51 u16 res_x; 52 u16 res_y; 53 }; 54 55 static int is_not_elan_touchpad(struct hid_device *hdev) 56 { 57 if (hdev->bus == BUS_USB) { 58 struct usb_interface *intf = to_usb_interface(hdev->dev.parent); 59 60 return (intf->altsetting->desc.bInterfaceNumber != 61 ELAN_TP_USB_INTF); 62 } 63 64 return 0; 65 } 66 67 static int elan_input_mapping(struct hid_device *hdev, struct hid_input *hi, 68 struct hid_field *field, struct hid_usage *usage, 69 unsigned long **bit, int *max) 70 { 71 if (is_not_elan_touchpad(hdev)) 72 return 0; 73 74 if (field->report->id == ELAN_SINGLE_FINGER || 75 field->report->id == ELAN_MT_FIRST_FINGER || 76 field->report->id == ELAN_MT_SECOND_FINGER || 77 field->report->id == ELAN_MT_I2C) 78 return -1; 79 80 return 0; 81 } 82 83 static int elan_get_device_param(struct hid_device *hdev, 84 unsigned char *dmabuf, unsigned char param) 85 { 86 int ret; 87 88 dmabuf[0] = ELAN_FEATURE_REPORT; 89 dmabuf[1] = 0x05; 90 dmabuf[2] = 0x03; 91 dmabuf[3] = param; 92 dmabuf[4] = 0x01; 93 94 ret = hid_hw_raw_request(hdev, ELAN_FEATURE_REPORT, dmabuf, 95 ELAN_FEATURE_SIZE, HID_FEATURE_REPORT, 96 HID_REQ_SET_REPORT); 97 if (ret != ELAN_FEATURE_SIZE) { 98 hid_err(hdev, "Set report error for parm %d: %d\n", param, ret); 99 return ret; 100 } 101 102 ret = hid_hw_raw_request(hdev, ELAN_FEATURE_REPORT, dmabuf, 103 ELAN_FEATURE_SIZE, HID_FEATURE_REPORT, 104 HID_REQ_GET_REPORT); 105 if (ret != ELAN_FEATURE_SIZE) { 106 hid_err(hdev, "Get report error for parm %d: %d\n", param, ret); 107 return ret; 108 } 109 110 return 0; 111 } 112 113 static unsigned int elan_convert_res(char val) 114 { 115 /* 116 * (value from firmware) * 10 + 790 = dpi 117 * dpi * 10 / 254 = dots/mm 118 */ 119 return (val * 10 + 790) * 10 / 254; 120 } 121 122 static int elan_get_device_params(struct hid_device *hdev) 123 { 124 struct elan_drvdata *drvdata = hid_get_drvdata(hdev); 125 unsigned char *dmabuf; 126 int ret; 127 128 dmabuf = kmalloc(ELAN_FEATURE_SIZE, GFP_KERNEL); 129 if (!dmabuf) 130 return -ENOMEM; 131 132 ret = elan_get_device_param(hdev, dmabuf, ELAN_PARAM_MAX_X); 133 if (ret) 134 goto err; 135 136 drvdata->max_x = (dmabuf[4] << 8) | dmabuf[3]; 137 138 ret = elan_get_device_param(hdev, dmabuf, ELAN_PARAM_MAX_Y); 139 if (ret) 140 goto err; 141 142 drvdata->max_y = (dmabuf[4] << 8) | dmabuf[3]; 143 144 ret = elan_get_device_param(hdev, dmabuf, ELAN_PARAM_RES); 145 if (ret) 146 goto err; 147 148 drvdata->res_x = elan_convert_res(dmabuf[3]); 149 drvdata->res_y = elan_convert_res(dmabuf[4]); 150 151 err: 152 kfree(dmabuf); 153 return ret; 154 } 155 156 static int elan_input_configured(struct hid_device *hdev, struct hid_input *hi) 157 { 158 int ret; 159 struct input_dev *input; 160 struct elan_drvdata *drvdata = hid_get_drvdata(hdev); 161 162 if (is_not_elan_touchpad(hdev)) 163 return 0; 164 165 ret = elan_get_device_params(hdev); 166 if (ret) 167 return ret; 168 169 input = devm_input_allocate_device(&hdev->dev); 170 if (!input) 171 return -ENOMEM; 172 173 input->name = "Elan Touchpad"; 174 input->phys = hdev->phys; 175 input->uniq = hdev->uniq; 176 input->id.bustype = hdev->bus; 177 input->id.vendor = hdev->vendor; 178 input->id.product = hdev->product; 179 input->id.version = hdev->version; 180 input->dev.parent = &hdev->dev; 181 182 input_set_abs_params(input, ABS_MT_POSITION_X, 0, drvdata->max_x, 183 0, 0); 184 input_set_abs_params(input, ABS_MT_POSITION_Y, 0, drvdata->max_y, 185 0, 0); 186 input_set_abs_params(input, ABS_MT_PRESSURE, 0, ELAN_MAX_PRESSURE, 187 0, 0); 188 189 __set_bit(BTN_LEFT, input->keybit); 190 __set_bit(INPUT_PROP_BUTTONPAD, input->propbit); 191 192 ret = input_mt_init_slots(input, ELAN_MAX_FINGERS, INPUT_MT_POINTER); 193 if (ret) { 194 hid_err(hdev, "Failed to init elan MT slots: %d\n", ret); 195 return ret; 196 } 197 198 input_abs_set_res(input, ABS_X, drvdata->res_x); 199 input_abs_set_res(input, ABS_Y, drvdata->res_y); 200 201 ret = input_register_device(input); 202 if (ret) { 203 hid_err(hdev, "Failed to register elan input device: %d\n", 204 ret); 205 input_free_device(input); 206 return ret; 207 } 208 209 drvdata->input = input; 210 211 return 0; 212 } 213 214 static void elan_report_mt_slot(struct elan_drvdata *drvdata, u8 *data, 215 unsigned int slot_num) 216 { 217 struct input_dev *input = drvdata->input; 218 int x, y, p; 219 220 bool active = !!data; 221 222 input_mt_slot(input, slot_num); 223 input_mt_report_slot_state(input, MT_TOOL_FINGER, active); 224 if (active) { 225 x = ((data[0] & 0xF0) << 4) | data[1]; 226 y = drvdata->max_y - 227 (((data[0] & 0x07) << 8) | data[2]); 228 p = data[4]; 229 230 input_report_abs(input, ABS_MT_POSITION_X, x); 231 input_report_abs(input, ABS_MT_POSITION_Y, y); 232 input_report_abs(input, ABS_MT_PRESSURE, p); 233 } 234 } 235 236 static void elan_usb_report_input(struct elan_drvdata *drvdata, u8 *data) 237 { 238 int i; 239 struct input_dev *input = drvdata->input; 240 241 /* 242 * There is 3 types of reports: for single touch, 243 * for multitouch - first finger and for multitouch - second finger 244 * 245 * packet structure for ELAN_SINGLE_FINGER and ELAN_MT_FIRST_FINGER: 246 * 247 * byte 1: 1 0 0 0 0 0 0 1 // 0x81 or 0x82 248 * byte 2: 0 0 0 0 0 0 0 0 // looks like unused 249 * byte 3: f5 f4 f3 f2 f1 0 0 L 250 * byte 4: x12 x11 x10 x9 0? y11 y10 y9 251 * byte 5: x8 x7 x6 x5 x4 x3 x2 x1 252 * byte 6: y8 y7 y6 y5 y4 y3 y2 y1 253 * byte 7: sy4 sy3 sy2 sy1 sx4 sx3 sx2 sx1 254 * byte 8: p8 p7 p6 p5 p4 p3 p2 p1 255 * 256 * packet structure for ELAN_MT_SECOND_FINGER: 257 * 258 * byte 1: 1 0 0 0 0 0 1 1 // 0x83 259 * byte 2: x12 x11 x10 x9 0 y11 y10 y9 260 * byte 3: x8 x7 x6 x5 x4 x3 x2 x1 261 * byte 4: y8 y7 y6 y5 y4 y3 y2 y1 262 * byte 5: sy4 sy3 sy2 sy1 sx4 sx3 sx2 sx1 263 * byte 6: p8 p7 p6 p5 p4 p3 p2 p1 264 * byte 7: 0 0 0 0 0 0 0 0 265 * byte 8: 0 0 0 0 0 0 0 0 266 * 267 * f5-f1: finger touch bits 268 * L: clickpad button 269 * sy / sx: finger width / height expressed in traces, the total number 270 * of traces can be queried by doing a HID_REQ_SET_REPORT 271 * { 0x0d, 0x05, 0x03, 0x05, 0x01 } followed by a GET, in the 272 * returned buf, buf[3]=no-x-traces, buf[4]=no-y-traces. 273 * p: pressure 274 */ 275 276 if (data[0] == ELAN_SINGLE_FINGER) { 277 for (i = 0; i < ELAN_MAX_FINGERS; i++) { 278 if (data[2] & BIT(i + 3)) 279 elan_report_mt_slot(drvdata, data + 3, i); 280 else 281 elan_report_mt_slot(drvdata, NULL, i); 282 } 283 input_report_key(input, BTN_LEFT, data[2] & 0x01); 284 } 285 /* 286 * When touched with two fingers Elan touchpad will emit two HID reports 287 * first is ELAN_MT_FIRST_FINGER and second is ELAN_MT_SECOND_FINGER 288 * we will save ELAN_MT_FIRST_FINGER report and wait for 289 * ELAN_MT_SECOND_FINGER to finish multitouch 290 */ 291 if (data[0] == ELAN_MT_FIRST_FINGER) { 292 memcpy(drvdata->prev_report, data, 293 sizeof(drvdata->prev_report)); 294 return; 295 } 296 297 if (data[0] == ELAN_MT_SECOND_FINGER) { 298 int first = 0; 299 u8 *prev_report = drvdata->prev_report; 300 301 if (prev_report[0] != ELAN_MT_FIRST_FINGER) 302 return; 303 304 for (i = 0; i < ELAN_MAX_FINGERS; i++) { 305 if (prev_report[2] & BIT(i + 3)) { 306 if (!first) { 307 first = 1; 308 elan_report_mt_slot(drvdata, prev_report + 3, i); 309 } else { 310 elan_report_mt_slot(drvdata, data + 1, i); 311 } 312 } else { 313 elan_report_mt_slot(drvdata, NULL, i); 314 } 315 } 316 input_report_key(input, BTN_LEFT, prev_report[2] & 0x01); 317 } 318 319 input_mt_sync_frame(input); 320 input_sync(input); 321 } 322 323 static void elan_i2c_report_input(struct elan_drvdata *drvdata, u8 *data) 324 { 325 struct input_dev *input = drvdata->input; 326 u8 *finger_data; 327 int i; 328 329 /* 330 * Elan MT touchpads in i2c mode send finger data in the same format 331 * as in USB mode, but then with all fingers in a single packet. 332 * 333 * packet structure for ELAN_MT_I2C: 334 * 335 * byte 1: 1 0 0 1 1 1 0 1 // 0x5d 336 * byte 2: f5 f4 f3 f2 f1 0 0 L 337 * byte 3: x12 x11 x10 x9 0? y11 y10 y9 338 * byte 4: x8 x7 x6 x5 x4 x3 x2 x1 339 * byte 5: y8 y7 y6 y5 y4 y3 y2 y1 340 * byte 6: sy4 sy3 sy2 sy1 sx4 sx3 sx2 sx1 341 * byte 7: p8 p7 p6 p5 p4 p3 p2 p1 342 * byte 8-12: Same as byte 3-7 for second finger down 343 * byte 13-17: Same as byte 3-7 for third finger down 344 * byte 18-22: Same as byte 3-7 for fourth finger down 345 * byte 23-27: Same as byte 3-7 for fifth finger down 346 */ 347 348 finger_data = data + 2; 349 for (i = 0; i < ELAN_MAX_FINGERS; i++) { 350 if (data[1] & BIT(i + 3)) { 351 elan_report_mt_slot(drvdata, finger_data, i); 352 finger_data += ELAN_FINGER_DATA_LEN; 353 } else { 354 elan_report_mt_slot(drvdata, NULL, i); 355 } 356 } 357 358 input_report_key(input, BTN_LEFT, data[1] & 0x01); 359 input_mt_sync_frame(input); 360 input_sync(input); 361 } 362 363 static int elan_raw_event(struct hid_device *hdev, 364 struct hid_report *report, u8 *data, int size) 365 { 366 struct elan_drvdata *drvdata = hid_get_drvdata(hdev); 367 368 if (is_not_elan_touchpad(hdev)) 369 return 0; 370 371 if (data[0] == ELAN_SINGLE_FINGER || 372 data[0] == ELAN_MT_FIRST_FINGER || 373 data[0] == ELAN_MT_SECOND_FINGER) { 374 if (size == ELAN_INPUT_REPORT_SIZE) { 375 elan_usb_report_input(drvdata, data); 376 return 1; 377 } 378 } 379 380 if (data[0] == ELAN_MT_I2C && size == ELAN_I2C_REPORT_SIZE) { 381 elan_i2c_report_input(drvdata, data); 382 return 1; 383 } 384 385 return 0; 386 } 387 388 static int elan_start_multitouch(struct hid_device *hdev) 389 { 390 int ret; 391 392 /* 393 * This byte sequence will enable multitouch mode and disable 394 * mouse emulation 395 */ 396 const unsigned char buf[] = { 0x0D, 0x00, 0x03, 0x21, 0x00 }; 397 unsigned char *dmabuf = kmemdup(buf, sizeof(buf), GFP_KERNEL); 398 399 if (!dmabuf) 400 return -ENOMEM; 401 402 ret = hid_hw_raw_request(hdev, dmabuf[0], dmabuf, sizeof(buf), 403 HID_FEATURE_REPORT, HID_REQ_SET_REPORT); 404 405 kfree(dmabuf); 406 407 if (ret != sizeof(buf)) { 408 hid_err(hdev, "Failed to start multitouch: %d\n", ret); 409 return ret; 410 } 411 412 return 0; 413 } 414 415 static enum led_brightness elan_mute_led_get_brigtness(struct led_classdev *led_cdev) 416 { 417 struct device *dev = led_cdev->dev->parent; 418 struct hid_device *hdev = to_hid_device(dev); 419 struct elan_drvdata *drvdata = hid_get_drvdata(hdev); 420 421 return drvdata->mute_led_state; 422 } 423 424 static int elan_mute_led_set_brigtness(struct led_classdev *led_cdev, 425 enum led_brightness value) 426 { 427 int ret; 428 u8 led_state; 429 struct device *dev = led_cdev->dev->parent; 430 struct hid_device *hdev = to_hid_device(dev); 431 struct elan_drvdata *drvdata = hid_get_drvdata(hdev); 432 433 unsigned char *dmabuf = kzalloc(ELAN_LED_REPORT_SIZE, GFP_KERNEL); 434 435 if (!dmabuf) 436 return -ENOMEM; 437 438 led_state = !!value; 439 440 dmabuf[0] = ELAN_MUTE_LED_REPORT; 441 dmabuf[1] = 0x02; 442 dmabuf[2] = led_state; 443 444 ret = hid_hw_raw_request(hdev, dmabuf[0], dmabuf, ELAN_LED_REPORT_SIZE, 445 HID_FEATURE_REPORT, HID_REQ_SET_REPORT); 446 447 kfree(dmabuf); 448 449 if (ret != ELAN_LED_REPORT_SIZE) { 450 hid_err(hdev, "Failed to set mute led brightness: %d\n", ret); 451 return ret; 452 } 453 454 drvdata->mute_led_state = led_state; 455 return 0; 456 } 457 458 static int elan_init_mute_led(struct hid_device *hdev) 459 { 460 struct elan_drvdata *drvdata = hid_get_drvdata(hdev); 461 struct led_classdev *mute_led = &drvdata->mute_led; 462 463 mute_led->name = "elan:red:mute"; 464 mute_led->brightness_get = elan_mute_led_get_brigtness; 465 mute_led->brightness_set_blocking = elan_mute_led_set_brigtness; 466 mute_led->max_brightness = LED_ON; 467 mute_led->dev = &hdev->dev; 468 469 return devm_led_classdev_register(&hdev->dev, mute_led); 470 } 471 472 static int elan_probe(struct hid_device *hdev, const struct hid_device_id *id) 473 { 474 int ret; 475 struct elan_drvdata *drvdata; 476 477 drvdata = devm_kzalloc(&hdev->dev, sizeof(*drvdata), GFP_KERNEL); 478 479 if (!drvdata) 480 return -ENOMEM; 481 482 hid_set_drvdata(hdev, drvdata); 483 484 ret = hid_parse(hdev); 485 if (ret) { 486 hid_err(hdev, "Hid Parse failed\n"); 487 return ret; 488 } 489 490 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT); 491 if (ret) { 492 hid_err(hdev, "Hid hw start failed\n"); 493 return ret; 494 } 495 496 if (is_not_elan_touchpad(hdev)) 497 return 0; 498 499 if (!drvdata->input) { 500 hid_err(hdev, "Input device is not registered\n"); 501 ret = -ENAVAIL; 502 goto err; 503 } 504 505 ret = elan_start_multitouch(hdev); 506 if (ret) 507 goto err; 508 509 if (id->driver_data & ELAN_HAS_LED) { 510 ret = elan_init_mute_led(hdev); 511 if (ret) 512 goto err; 513 } 514 515 return 0; 516 err: 517 hid_hw_stop(hdev); 518 return ret; 519 } 520 521 static void elan_remove(struct hid_device *hdev) 522 { 523 hid_hw_stop(hdev); 524 } 525 526 static const struct hid_device_id elan_devices[] = { 527 { HID_USB_DEVICE(USB_VENDOR_ID_ELAN, USB_DEVICE_ID_HP_X2), 528 .driver_data = ELAN_HAS_LED }, 529 { HID_USB_DEVICE(USB_VENDOR_ID_ELAN, USB_DEVICE_ID_HP_X2_10_COVER), 530 .driver_data = ELAN_HAS_LED }, 531 { HID_I2C_DEVICE(USB_VENDOR_ID_ELAN, USB_DEVICE_ID_TOSHIBA_CLICK_L9W) }, 532 { } 533 }; 534 MODULE_DEVICE_TABLE(hid, elan_devices); 535 536 static struct hid_driver elan_driver = { 537 .name = "elan", 538 .id_table = elan_devices, 539 .input_mapping = elan_input_mapping, 540 .input_configured = elan_input_configured, 541 .raw_event = elan_raw_event, 542 .probe = elan_probe, 543 .remove = elan_remove, 544 }; 545 546 module_hid_driver(elan_driver); 547 548 MODULE_LICENSE("GPL"); 549 MODULE_AUTHOR("Alexandrov Stanislav"); 550 MODULE_DESCRIPTION("Driver for HID ELAN Touchpads"); 551