1 /* 2 * HID over I2C protocol implementation 3 * 4 * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com> 5 * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France 6 * Copyright (c) 2012 Red Hat, Inc 7 * 8 * This code is partly based on "USB HID support for Linux": 9 * 10 * Copyright (c) 1999 Andreas Gal 11 * Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz> 12 * Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc 13 * Copyright (c) 2007-2008 Oliver Neukum 14 * Copyright (c) 2006-2010 Jiri Kosina 15 * 16 * This file is subject to the terms and conditions of the GNU General Public 17 * License. See the file COPYING in the main directory of this archive for 18 * more details. 19 */ 20 21 #include <linux/module.h> 22 #include <linux/i2c.h> 23 #include <linux/interrupt.h> 24 #include <linux/input.h> 25 #include <linux/irq.h> 26 #include <linux/delay.h> 27 #include <linux/slab.h> 28 #include <linux/pm.h> 29 #include <linux/device.h> 30 #include <linux/wait.h> 31 #include <linux/err.h> 32 #include <linux/string.h> 33 #include <linux/list.h> 34 #include <linux/jiffies.h> 35 #include <linux/kernel.h> 36 #include <linux/hid.h> 37 #include <linux/mutex.h> 38 #include <linux/acpi.h> 39 #include <linux/of.h> 40 #include <linux/regulator/consumer.h> 41 42 #include <linux/platform_data/i2c-hid.h> 43 44 #include "../hid-ids.h" 45 #include "i2c-hid.h" 46 47 /* quirks to control the device */ 48 #define I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV BIT(0) 49 #define I2C_HID_QUIRK_NO_IRQ_AFTER_RESET BIT(1) 50 #define I2C_HID_QUIRK_BOGUS_IRQ BIT(4) 51 #define I2C_HID_QUIRK_RESET_ON_RESUME BIT(5) 52 53 /* flags */ 54 #define I2C_HID_STARTED 0 55 #define I2C_HID_RESET_PENDING 1 56 #define I2C_HID_READ_PENDING 2 57 58 #define I2C_HID_PWR_ON 0x00 59 #define I2C_HID_PWR_SLEEP 0x01 60 61 /* debug option */ 62 static bool debug; 63 module_param(debug, bool, 0444); 64 MODULE_PARM_DESC(debug, "print a lot of debug information"); 65 66 #define i2c_hid_dbg(ihid, fmt, arg...) \ 67 do { \ 68 if (debug) \ 69 dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \ 70 } while (0) 71 72 struct i2c_hid_desc { 73 __le16 wHIDDescLength; 74 __le16 bcdVersion; 75 __le16 wReportDescLength; 76 __le16 wReportDescRegister; 77 __le16 wInputRegister; 78 __le16 wMaxInputLength; 79 __le16 wOutputRegister; 80 __le16 wMaxOutputLength; 81 __le16 wCommandRegister; 82 __le16 wDataRegister; 83 __le16 wVendorID; 84 __le16 wProductID; 85 __le16 wVersionID; 86 __le32 reserved; 87 } __packed; 88 89 struct i2c_hid_cmd { 90 unsigned int registerIndex; 91 __u8 opcode; 92 unsigned int length; 93 bool wait; 94 }; 95 96 union command { 97 u8 data[0]; 98 struct cmd { 99 __le16 reg; 100 __u8 reportTypeID; 101 __u8 opcode; 102 } __packed c; 103 }; 104 105 #define I2C_HID_CMD(opcode_) \ 106 .opcode = opcode_, .length = 4, \ 107 .registerIndex = offsetof(struct i2c_hid_desc, wCommandRegister) 108 109 /* fetch HID descriptor */ 110 static const struct i2c_hid_cmd hid_descr_cmd = { .length = 2 }; 111 /* fetch report descriptors */ 112 static const struct i2c_hid_cmd hid_report_descr_cmd = { 113 .registerIndex = offsetof(struct i2c_hid_desc, 114 wReportDescRegister), 115 .opcode = 0x00, 116 .length = 2 }; 117 /* commands */ 118 static const struct i2c_hid_cmd hid_reset_cmd = { I2C_HID_CMD(0x01), 119 .wait = true }; 120 static const struct i2c_hid_cmd hid_get_report_cmd = { I2C_HID_CMD(0x02) }; 121 static const struct i2c_hid_cmd hid_set_report_cmd = { I2C_HID_CMD(0x03) }; 122 static const struct i2c_hid_cmd hid_set_power_cmd = { I2C_HID_CMD(0x08) }; 123 static const struct i2c_hid_cmd hid_no_cmd = { .length = 0 }; 124 125 /* 126 * These definitions are not used here, but are defined by the spec. 127 * Keeping them here for documentation purposes. 128 * 129 * static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) }; 130 * static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) }; 131 * static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) }; 132 * static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) }; 133 */ 134 135 /* The main device structure */ 136 struct i2c_hid { 137 struct i2c_client *client; /* i2c client */ 138 struct hid_device *hid; /* pointer to corresponding HID dev */ 139 union { 140 __u8 hdesc_buffer[sizeof(struct i2c_hid_desc)]; 141 struct i2c_hid_desc hdesc; /* the HID Descriptor */ 142 }; 143 __le16 wHIDDescRegister; /* location of the i2c 144 * register of the HID 145 * descriptor. */ 146 unsigned int bufsize; /* i2c buffer size */ 147 u8 *inbuf; /* Input buffer */ 148 u8 *rawbuf; /* Raw Input buffer */ 149 u8 *cmdbuf; /* Command buffer */ 150 u8 *argsbuf; /* Command arguments buffer */ 151 152 unsigned long flags; /* device flags */ 153 unsigned long quirks; /* Various quirks */ 154 155 wait_queue_head_t wait; /* For waiting the interrupt */ 156 157 struct i2c_hid_platform_data pdata; 158 159 bool irq_wake_enabled; 160 struct mutex reset_lock; 161 }; 162 163 static const struct i2c_hid_quirks { 164 __u16 idVendor; 165 __u16 idProduct; 166 __u32 quirks; 167 } i2c_hid_quirks[] = { 168 { USB_VENDOR_ID_WEIDA, HID_ANY_ID, 169 I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV }, 170 { I2C_VENDOR_ID_HANTICK, I2C_PRODUCT_ID_HANTICK_5288, 171 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET }, 172 { I2C_VENDOR_ID_RAYDIUM, I2C_PRODUCT_ID_RAYDIUM_3118, 173 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET }, 174 { USB_VENDOR_ID_ELAN, HID_ANY_ID, 175 I2C_HID_QUIRK_BOGUS_IRQ }, 176 { USB_VENDOR_ID_ALPS_JP, HID_ANY_ID, 177 I2C_HID_QUIRK_RESET_ON_RESUME }, 178 { 0, 0 } 179 }; 180 181 /* 182 * i2c_hid_lookup_quirk: return any quirks associated with a I2C HID device 183 * @idVendor: the 16-bit vendor ID 184 * @idProduct: the 16-bit product ID 185 * 186 * Returns: a u32 quirks value. 187 */ 188 static u32 i2c_hid_lookup_quirk(const u16 idVendor, const u16 idProduct) 189 { 190 u32 quirks = 0; 191 int n; 192 193 for (n = 0; i2c_hid_quirks[n].idVendor; n++) 194 if (i2c_hid_quirks[n].idVendor == idVendor && 195 (i2c_hid_quirks[n].idProduct == (__u16)HID_ANY_ID || 196 i2c_hid_quirks[n].idProduct == idProduct)) 197 quirks = i2c_hid_quirks[n].quirks; 198 199 return quirks; 200 } 201 202 static int __i2c_hid_command(struct i2c_client *client, 203 const struct i2c_hid_cmd *command, u8 reportID, 204 u8 reportType, u8 *args, int args_len, 205 unsigned char *buf_recv, int data_len) 206 { 207 struct i2c_hid *ihid = i2c_get_clientdata(client); 208 union command *cmd = (union command *)ihid->cmdbuf; 209 int ret; 210 struct i2c_msg msg[2]; 211 int msg_num = 1; 212 213 int length = command->length; 214 bool wait = command->wait; 215 unsigned int registerIndex = command->registerIndex; 216 217 /* special case for hid_descr_cmd */ 218 if (command == &hid_descr_cmd) { 219 cmd->c.reg = ihid->wHIDDescRegister; 220 } else { 221 cmd->data[0] = ihid->hdesc_buffer[registerIndex]; 222 cmd->data[1] = ihid->hdesc_buffer[registerIndex + 1]; 223 } 224 225 if (length > 2) { 226 cmd->c.opcode = command->opcode; 227 cmd->c.reportTypeID = reportID | reportType << 4; 228 } 229 230 memcpy(cmd->data + length, args, args_len); 231 length += args_len; 232 233 i2c_hid_dbg(ihid, "%s: cmd=%*ph\n", __func__, length, cmd->data); 234 235 msg[0].addr = client->addr; 236 msg[0].flags = client->flags & I2C_M_TEN; 237 msg[0].len = length; 238 msg[0].buf = cmd->data; 239 if (data_len > 0) { 240 msg[1].addr = client->addr; 241 msg[1].flags = client->flags & I2C_M_TEN; 242 msg[1].flags |= I2C_M_RD; 243 msg[1].len = data_len; 244 msg[1].buf = buf_recv; 245 msg_num = 2; 246 set_bit(I2C_HID_READ_PENDING, &ihid->flags); 247 } 248 249 if (wait) 250 set_bit(I2C_HID_RESET_PENDING, &ihid->flags); 251 252 ret = i2c_transfer(client->adapter, msg, msg_num); 253 254 if (data_len > 0) 255 clear_bit(I2C_HID_READ_PENDING, &ihid->flags); 256 257 if (ret != msg_num) 258 return ret < 0 ? ret : -EIO; 259 260 ret = 0; 261 262 if (wait && (ihid->quirks & I2C_HID_QUIRK_NO_IRQ_AFTER_RESET)) { 263 msleep(100); 264 } else if (wait) { 265 i2c_hid_dbg(ihid, "%s: waiting...\n", __func__); 266 if (!wait_event_timeout(ihid->wait, 267 !test_bit(I2C_HID_RESET_PENDING, &ihid->flags), 268 msecs_to_jiffies(5000))) 269 ret = -ENODATA; 270 i2c_hid_dbg(ihid, "%s: finished.\n", __func__); 271 } 272 273 return ret; 274 } 275 276 static int i2c_hid_command(struct i2c_client *client, 277 const struct i2c_hid_cmd *command, 278 unsigned char *buf_recv, int data_len) 279 { 280 return __i2c_hid_command(client, command, 0, 0, NULL, 0, 281 buf_recv, data_len); 282 } 283 284 static int i2c_hid_get_report(struct i2c_client *client, u8 reportType, 285 u8 reportID, unsigned char *buf_recv, int data_len) 286 { 287 struct i2c_hid *ihid = i2c_get_clientdata(client); 288 u8 args[3]; 289 int ret; 290 int args_len = 0; 291 u16 readRegister = le16_to_cpu(ihid->hdesc.wDataRegister); 292 293 i2c_hid_dbg(ihid, "%s\n", __func__); 294 295 if (reportID >= 0x0F) { 296 args[args_len++] = reportID; 297 reportID = 0x0F; 298 } 299 300 args[args_len++] = readRegister & 0xFF; 301 args[args_len++] = readRegister >> 8; 302 303 ret = __i2c_hid_command(client, &hid_get_report_cmd, reportID, 304 reportType, args, args_len, buf_recv, data_len); 305 if (ret) { 306 dev_err(&client->dev, 307 "failed to retrieve report from device.\n"); 308 return ret; 309 } 310 311 return 0; 312 } 313 314 /** 315 * i2c_hid_set_or_send_report: forward an incoming report to the device 316 * @client: the i2c_client of the device 317 * @reportType: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT 318 * @reportID: the report ID 319 * @buf: the actual data to transfer, without the report ID 320 * @len: size of buf 321 * @use_data: true: use SET_REPORT HID command, false: send plain OUTPUT report 322 */ 323 static int i2c_hid_set_or_send_report(struct i2c_client *client, u8 reportType, 324 u8 reportID, unsigned char *buf, size_t data_len, bool use_data) 325 { 326 struct i2c_hid *ihid = i2c_get_clientdata(client); 327 u8 *args = ihid->argsbuf; 328 const struct i2c_hid_cmd *hidcmd; 329 int ret; 330 u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister); 331 u16 outputRegister = le16_to_cpu(ihid->hdesc.wOutputRegister); 332 u16 maxOutputLength = le16_to_cpu(ihid->hdesc.wMaxOutputLength); 333 u16 size; 334 int args_len; 335 int index = 0; 336 337 i2c_hid_dbg(ihid, "%s\n", __func__); 338 339 if (data_len > ihid->bufsize) 340 return -EINVAL; 341 342 size = 2 /* size */ + 343 (reportID ? 1 : 0) /* reportID */ + 344 data_len /* buf */; 345 args_len = (reportID >= 0x0F ? 1 : 0) /* optional third byte */ + 346 2 /* dataRegister */ + 347 size /* args */; 348 349 if (!use_data && maxOutputLength == 0) 350 return -ENOSYS; 351 352 if (reportID >= 0x0F) { 353 args[index++] = reportID; 354 reportID = 0x0F; 355 } 356 357 /* 358 * use the data register for feature reports or if the device does not 359 * support the output register 360 */ 361 if (use_data) { 362 args[index++] = dataRegister & 0xFF; 363 args[index++] = dataRegister >> 8; 364 hidcmd = &hid_set_report_cmd; 365 } else { 366 args[index++] = outputRegister & 0xFF; 367 args[index++] = outputRegister >> 8; 368 hidcmd = &hid_no_cmd; 369 } 370 371 args[index++] = size & 0xFF; 372 args[index++] = size >> 8; 373 374 if (reportID) 375 args[index++] = reportID; 376 377 memcpy(&args[index], buf, data_len); 378 379 ret = __i2c_hid_command(client, hidcmd, reportID, 380 reportType, args, args_len, NULL, 0); 381 if (ret) { 382 dev_err(&client->dev, "failed to set a report to device.\n"); 383 return ret; 384 } 385 386 return data_len; 387 } 388 389 static int i2c_hid_set_power(struct i2c_client *client, int power_state) 390 { 391 struct i2c_hid *ihid = i2c_get_clientdata(client); 392 int ret; 393 394 i2c_hid_dbg(ihid, "%s\n", __func__); 395 396 /* 397 * Some devices require to send a command to wakeup before power on. 398 * The call will get a return value (EREMOTEIO) but device will be 399 * triggered and activated. After that, it goes like a normal device. 400 */ 401 if (power_state == I2C_HID_PWR_ON && 402 ihid->quirks & I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV) { 403 ret = i2c_hid_command(client, &hid_set_power_cmd, NULL, 0); 404 405 /* Device was already activated */ 406 if (!ret) 407 goto set_pwr_exit; 408 } 409 410 ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state, 411 0, NULL, 0, NULL, 0); 412 413 if (ret) 414 dev_err(&client->dev, "failed to change power setting.\n"); 415 416 set_pwr_exit: 417 return ret; 418 } 419 420 static int i2c_hid_hwreset(struct i2c_client *client) 421 { 422 struct i2c_hid *ihid = i2c_get_clientdata(client); 423 int ret; 424 425 i2c_hid_dbg(ihid, "%s\n", __func__); 426 427 /* 428 * This prevents sending feature reports while the device is 429 * being reset. Otherwise we may lose the reset complete 430 * interrupt. 431 */ 432 mutex_lock(&ihid->reset_lock); 433 434 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON); 435 if (ret) 436 goto out_unlock; 437 438 /* 439 * The HID over I2C specification states that if a DEVICE needs time 440 * after the PWR_ON request, it should utilise CLOCK stretching. 441 * However, it has been observered that the Windows driver provides a 442 * 1ms sleep between the PWR_ON and RESET requests and that some devices 443 * rely on this. 444 */ 445 usleep_range(1000, 5000); 446 447 i2c_hid_dbg(ihid, "resetting...\n"); 448 449 ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0); 450 if (ret) { 451 dev_err(&client->dev, "failed to reset device.\n"); 452 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); 453 goto out_unlock; 454 } 455 456 /* At least some SIS devices need this after reset */ 457 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON); 458 459 out_unlock: 460 mutex_unlock(&ihid->reset_lock); 461 return ret; 462 } 463 464 static void i2c_hid_get_input(struct i2c_hid *ihid) 465 { 466 int ret; 467 u32 ret_size; 468 int size = le16_to_cpu(ihid->hdesc.wMaxInputLength); 469 470 if (size > ihid->bufsize) 471 size = ihid->bufsize; 472 473 ret = i2c_master_recv(ihid->client, ihid->inbuf, size); 474 if (ret != size) { 475 if (ret < 0) 476 return; 477 478 dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n", 479 __func__, ret, size); 480 return; 481 } 482 483 ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8; 484 485 if (!ret_size) { 486 /* host or device initiated RESET completed */ 487 if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags)) 488 wake_up(&ihid->wait); 489 return; 490 } 491 492 if (ihid->quirks & I2C_HID_QUIRK_BOGUS_IRQ && ret_size == 0xffff) { 493 dev_warn_once(&ihid->client->dev, "%s: IRQ triggered but " 494 "there's no data\n", __func__); 495 return; 496 } 497 498 if ((ret_size > size) || (ret_size < 2)) { 499 dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n", 500 __func__, size, ret_size); 501 return; 502 } 503 504 i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf); 505 506 if (test_bit(I2C_HID_STARTED, &ihid->flags)) 507 hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2, 508 ret_size - 2, 1); 509 510 return; 511 } 512 513 static irqreturn_t i2c_hid_irq(int irq, void *dev_id) 514 { 515 struct i2c_hid *ihid = dev_id; 516 517 if (test_bit(I2C_HID_READ_PENDING, &ihid->flags)) 518 return IRQ_HANDLED; 519 520 i2c_hid_get_input(ihid); 521 522 return IRQ_HANDLED; 523 } 524 525 static int i2c_hid_get_report_length(struct hid_report *report) 526 { 527 return ((report->size - 1) >> 3) + 1 + 528 report->device->report_enum[report->type].numbered + 2; 529 } 530 531 /* 532 * Traverse the supplied list of reports and find the longest 533 */ 534 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type, 535 unsigned int *max) 536 { 537 struct hid_report *report; 538 unsigned int size; 539 540 /* We should not rely on wMaxInputLength, as some devices may set it to 541 * a wrong length. */ 542 list_for_each_entry(report, &hid->report_enum[type].report_list, list) { 543 size = i2c_hid_get_report_length(report); 544 if (*max < size) 545 *max = size; 546 } 547 } 548 549 static void i2c_hid_free_buffers(struct i2c_hid *ihid) 550 { 551 kfree(ihid->inbuf); 552 kfree(ihid->rawbuf); 553 kfree(ihid->argsbuf); 554 kfree(ihid->cmdbuf); 555 ihid->inbuf = NULL; 556 ihid->rawbuf = NULL; 557 ihid->cmdbuf = NULL; 558 ihid->argsbuf = NULL; 559 ihid->bufsize = 0; 560 } 561 562 static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size) 563 { 564 /* the worst case is computed from the set_report command with a 565 * reportID > 15 and the maximum report length */ 566 int args_len = sizeof(__u8) + /* ReportID */ 567 sizeof(__u8) + /* optional ReportID byte */ 568 sizeof(__u16) + /* data register */ 569 sizeof(__u16) + /* size of the report */ 570 report_size; /* report */ 571 572 ihid->inbuf = kzalloc(report_size, GFP_KERNEL); 573 ihid->rawbuf = kzalloc(report_size, GFP_KERNEL); 574 ihid->argsbuf = kzalloc(args_len, GFP_KERNEL); 575 ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL); 576 577 if (!ihid->inbuf || !ihid->rawbuf || !ihid->argsbuf || !ihid->cmdbuf) { 578 i2c_hid_free_buffers(ihid); 579 return -ENOMEM; 580 } 581 582 ihid->bufsize = report_size; 583 584 return 0; 585 } 586 587 static int i2c_hid_get_raw_report(struct hid_device *hid, 588 unsigned char report_number, __u8 *buf, size_t count, 589 unsigned char report_type) 590 { 591 struct i2c_client *client = hid->driver_data; 592 struct i2c_hid *ihid = i2c_get_clientdata(client); 593 size_t ret_count, ask_count; 594 int ret; 595 596 if (report_type == HID_OUTPUT_REPORT) 597 return -EINVAL; 598 599 /* +2 bytes to include the size of the reply in the query buffer */ 600 ask_count = min(count + 2, (size_t)ihid->bufsize); 601 602 ret = i2c_hid_get_report(client, 603 report_type == HID_FEATURE_REPORT ? 0x03 : 0x01, 604 report_number, ihid->rawbuf, ask_count); 605 606 if (ret < 0) 607 return ret; 608 609 ret_count = ihid->rawbuf[0] | (ihid->rawbuf[1] << 8); 610 611 if (ret_count <= 2) 612 return 0; 613 614 ret_count = min(ret_count, ask_count); 615 616 /* The query buffer contains the size, dropping it in the reply */ 617 count = min(count, ret_count - 2); 618 memcpy(buf, ihid->rawbuf + 2, count); 619 620 return count; 621 } 622 623 static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf, 624 size_t count, unsigned char report_type, bool use_data) 625 { 626 struct i2c_client *client = hid->driver_data; 627 struct i2c_hid *ihid = i2c_get_clientdata(client); 628 int report_id = buf[0]; 629 int ret; 630 631 if (report_type == HID_INPUT_REPORT) 632 return -EINVAL; 633 634 mutex_lock(&ihid->reset_lock); 635 636 if (report_id) { 637 buf++; 638 count--; 639 } 640 641 ret = i2c_hid_set_or_send_report(client, 642 report_type == HID_FEATURE_REPORT ? 0x03 : 0x02, 643 report_id, buf, count, use_data); 644 645 if (report_id && ret >= 0) 646 ret++; /* add report_id to the number of transfered bytes */ 647 648 mutex_unlock(&ihid->reset_lock); 649 650 return ret; 651 } 652 653 static int i2c_hid_output_report(struct hid_device *hid, __u8 *buf, 654 size_t count) 655 { 656 return i2c_hid_output_raw_report(hid, buf, count, HID_OUTPUT_REPORT, 657 false); 658 } 659 660 static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum, 661 __u8 *buf, size_t len, unsigned char rtype, 662 int reqtype) 663 { 664 switch (reqtype) { 665 case HID_REQ_GET_REPORT: 666 return i2c_hid_get_raw_report(hid, reportnum, buf, len, rtype); 667 case HID_REQ_SET_REPORT: 668 if (buf[0] != reportnum) 669 return -EINVAL; 670 return i2c_hid_output_raw_report(hid, buf, len, rtype, true); 671 default: 672 return -EIO; 673 } 674 } 675 676 static int i2c_hid_parse(struct hid_device *hid) 677 { 678 struct i2c_client *client = hid->driver_data; 679 struct i2c_hid *ihid = i2c_get_clientdata(client); 680 struct i2c_hid_desc *hdesc = &ihid->hdesc; 681 unsigned int rsize; 682 char *rdesc; 683 int ret; 684 int tries = 3; 685 char *use_override; 686 687 i2c_hid_dbg(ihid, "entering %s\n", __func__); 688 689 rsize = le16_to_cpu(hdesc->wReportDescLength); 690 if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) { 691 dbg_hid("weird size of report descriptor (%u)\n", rsize); 692 return -EINVAL; 693 } 694 695 do { 696 ret = i2c_hid_hwreset(client); 697 if (ret) 698 msleep(1000); 699 } while (tries-- > 0 && ret); 700 701 if (ret) 702 return ret; 703 704 use_override = i2c_hid_get_dmi_hid_report_desc_override(client->name, 705 &rsize); 706 707 if (use_override) { 708 rdesc = use_override; 709 i2c_hid_dbg(ihid, "Using a HID report descriptor override\n"); 710 } else { 711 rdesc = kzalloc(rsize, GFP_KERNEL); 712 713 if (!rdesc) { 714 dbg_hid("couldn't allocate rdesc memory\n"); 715 return -ENOMEM; 716 } 717 718 i2c_hid_dbg(ihid, "asking HID report descriptor\n"); 719 720 ret = i2c_hid_command(client, &hid_report_descr_cmd, 721 rdesc, rsize); 722 if (ret) { 723 hid_err(hid, "reading report descriptor failed\n"); 724 kfree(rdesc); 725 return -EIO; 726 } 727 } 728 729 i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc); 730 731 ret = hid_parse_report(hid, rdesc, rsize); 732 if (!use_override) 733 kfree(rdesc); 734 735 if (ret) { 736 dbg_hid("parsing report descriptor failed\n"); 737 return ret; 738 } 739 740 return 0; 741 } 742 743 static int i2c_hid_start(struct hid_device *hid) 744 { 745 struct i2c_client *client = hid->driver_data; 746 struct i2c_hid *ihid = i2c_get_clientdata(client); 747 int ret; 748 unsigned int bufsize = HID_MIN_BUFFER_SIZE; 749 750 i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize); 751 i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize); 752 i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize); 753 754 if (bufsize > ihid->bufsize) { 755 disable_irq(client->irq); 756 i2c_hid_free_buffers(ihid); 757 758 ret = i2c_hid_alloc_buffers(ihid, bufsize); 759 enable_irq(client->irq); 760 761 if (ret) 762 return ret; 763 } 764 765 return 0; 766 } 767 768 static void i2c_hid_stop(struct hid_device *hid) 769 { 770 hid->claimed = 0; 771 } 772 773 static int i2c_hid_open(struct hid_device *hid) 774 { 775 struct i2c_client *client = hid->driver_data; 776 struct i2c_hid *ihid = i2c_get_clientdata(client); 777 778 set_bit(I2C_HID_STARTED, &ihid->flags); 779 return 0; 780 } 781 782 static void i2c_hid_close(struct hid_device *hid) 783 { 784 struct i2c_client *client = hid->driver_data; 785 struct i2c_hid *ihid = i2c_get_clientdata(client); 786 787 clear_bit(I2C_HID_STARTED, &ihid->flags); 788 } 789 790 struct hid_ll_driver i2c_hid_ll_driver = { 791 .parse = i2c_hid_parse, 792 .start = i2c_hid_start, 793 .stop = i2c_hid_stop, 794 .open = i2c_hid_open, 795 .close = i2c_hid_close, 796 .output_report = i2c_hid_output_report, 797 .raw_request = i2c_hid_raw_request, 798 }; 799 EXPORT_SYMBOL_GPL(i2c_hid_ll_driver); 800 801 static int i2c_hid_init_irq(struct i2c_client *client) 802 { 803 struct i2c_hid *ihid = i2c_get_clientdata(client); 804 unsigned long irqflags = 0; 805 int ret; 806 807 dev_dbg(&client->dev, "Requesting IRQ: %d\n", client->irq); 808 809 if (!irq_get_trigger_type(client->irq)) 810 irqflags = IRQF_TRIGGER_LOW; 811 812 ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq, 813 irqflags | IRQF_ONESHOT, client->name, ihid); 814 if (ret < 0) { 815 dev_warn(&client->dev, 816 "Could not register for %s interrupt, irq = %d," 817 " ret = %d\n", 818 client->name, client->irq, ret); 819 820 return ret; 821 } 822 823 return 0; 824 } 825 826 static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid) 827 { 828 struct i2c_client *client = ihid->client; 829 struct i2c_hid_desc *hdesc = &ihid->hdesc; 830 unsigned int dsize; 831 int ret; 832 833 /* i2c hid fetch using a fixed descriptor size (30 bytes) */ 834 if (i2c_hid_get_dmi_i2c_hid_desc_override(client->name)) { 835 i2c_hid_dbg(ihid, "Using a HID descriptor override\n"); 836 ihid->hdesc = 837 *i2c_hid_get_dmi_i2c_hid_desc_override(client->name); 838 } else { 839 i2c_hid_dbg(ihid, "Fetching the HID descriptor\n"); 840 ret = i2c_hid_command(client, &hid_descr_cmd, 841 ihid->hdesc_buffer, 842 sizeof(struct i2c_hid_desc)); 843 if (ret) { 844 dev_err(&client->dev, "hid_descr_cmd failed\n"); 845 return -ENODEV; 846 } 847 } 848 849 /* Validate the length of HID descriptor, the 4 first bytes: 850 * bytes 0-1 -> length 851 * bytes 2-3 -> bcdVersion (has to be 1.00) */ 852 /* check bcdVersion == 1.0 */ 853 if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) { 854 dev_err(&client->dev, 855 "unexpected HID descriptor bcdVersion (0x%04hx)\n", 856 le16_to_cpu(hdesc->bcdVersion)); 857 return -ENODEV; 858 } 859 860 /* Descriptor length should be 30 bytes as per the specification */ 861 dsize = le16_to_cpu(hdesc->wHIDDescLength); 862 if (dsize != sizeof(struct i2c_hid_desc)) { 863 dev_err(&client->dev, "weird size of HID descriptor (%u)\n", 864 dsize); 865 return -ENODEV; 866 } 867 i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer); 868 return 0; 869 } 870 871 #ifdef CONFIG_ACPI 872 static const struct acpi_device_id i2c_hid_acpi_blacklist[] = { 873 /* 874 * The CHPN0001 ACPI device, which is used to describe the Chipone 875 * ICN8505 controller, has a _CID of PNP0C50 but is not HID compatible. 876 */ 877 {"CHPN0001", 0 }, 878 { }, 879 }; 880 881 static int i2c_hid_acpi_pdata(struct i2c_client *client, 882 struct i2c_hid_platform_data *pdata) 883 { 884 static guid_t i2c_hid_guid = 885 GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555, 886 0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE); 887 union acpi_object *obj; 888 struct acpi_device *adev; 889 acpi_handle handle; 890 891 handle = ACPI_HANDLE(&client->dev); 892 if (!handle || acpi_bus_get_device(handle, &adev)) { 893 dev_err(&client->dev, "Error could not get ACPI device\n"); 894 return -ENODEV; 895 } 896 897 if (acpi_match_device_ids(adev, i2c_hid_acpi_blacklist) == 0) 898 return -ENODEV; 899 900 obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL, 901 ACPI_TYPE_INTEGER); 902 if (!obj) { 903 dev_err(&client->dev, "Error _DSM call to get HID descriptor address failed\n"); 904 return -ENODEV; 905 } 906 907 pdata->hid_descriptor_address = obj->integer.value; 908 ACPI_FREE(obj); 909 910 return 0; 911 } 912 913 static void i2c_hid_acpi_fix_up_power(struct device *dev) 914 { 915 struct acpi_device *adev; 916 917 adev = ACPI_COMPANION(dev); 918 if (adev) 919 acpi_device_fix_up_power(adev); 920 } 921 922 static const struct acpi_device_id i2c_hid_acpi_match[] = { 923 {"ACPI0C50", 0 }, 924 {"PNP0C50", 0 }, 925 { }, 926 }; 927 MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match); 928 #else 929 static inline int i2c_hid_acpi_pdata(struct i2c_client *client, 930 struct i2c_hid_platform_data *pdata) 931 { 932 return -ENODEV; 933 } 934 935 static inline void i2c_hid_acpi_fix_up_power(struct device *dev) {} 936 #endif 937 938 #ifdef CONFIG_OF 939 static int i2c_hid_of_probe(struct i2c_client *client, 940 struct i2c_hid_platform_data *pdata) 941 { 942 struct device *dev = &client->dev; 943 u32 val; 944 int ret; 945 946 ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val); 947 if (ret) { 948 dev_err(&client->dev, "HID register address not provided\n"); 949 return -ENODEV; 950 } 951 if (val >> 16) { 952 dev_err(&client->dev, "Bad HID register address: 0x%08x\n", 953 val); 954 return -EINVAL; 955 } 956 pdata->hid_descriptor_address = val; 957 958 return 0; 959 } 960 961 static const struct of_device_id i2c_hid_of_match[] = { 962 { .compatible = "hid-over-i2c" }, 963 {}, 964 }; 965 MODULE_DEVICE_TABLE(of, i2c_hid_of_match); 966 #else 967 static inline int i2c_hid_of_probe(struct i2c_client *client, 968 struct i2c_hid_platform_data *pdata) 969 { 970 return -ENODEV; 971 } 972 #endif 973 974 static void i2c_hid_fwnode_probe(struct i2c_client *client, 975 struct i2c_hid_platform_data *pdata) 976 { 977 u32 val; 978 979 if (!device_property_read_u32(&client->dev, "post-power-on-delay-ms", 980 &val)) 981 pdata->post_power_delay_ms = val; 982 } 983 984 static int i2c_hid_probe(struct i2c_client *client, 985 const struct i2c_device_id *dev_id) 986 { 987 int ret; 988 struct i2c_hid *ihid; 989 struct hid_device *hid; 990 __u16 hidRegister; 991 struct i2c_hid_platform_data *platform_data = client->dev.platform_data; 992 993 dbg_hid("HID probe called for i2c 0x%02x\n", client->addr); 994 995 if (!client->irq) { 996 dev_err(&client->dev, 997 "HID over i2c has not been provided an Int IRQ\n"); 998 return -EINVAL; 999 } 1000 1001 if (client->irq < 0) { 1002 if (client->irq != -EPROBE_DEFER) 1003 dev_err(&client->dev, 1004 "HID over i2c doesn't have a valid IRQ\n"); 1005 return client->irq; 1006 } 1007 1008 ihid = devm_kzalloc(&client->dev, sizeof(*ihid), GFP_KERNEL); 1009 if (!ihid) 1010 return -ENOMEM; 1011 1012 if (client->dev.of_node) { 1013 ret = i2c_hid_of_probe(client, &ihid->pdata); 1014 if (ret) 1015 return ret; 1016 } else if (!platform_data) { 1017 ret = i2c_hid_acpi_pdata(client, &ihid->pdata); 1018 if (ret) 1019 return ret; 1020 } else { 1021 ihid->pdata = *platform_data; 1022 } 1023 1024 /* Parse platform agnostic common properties from ACPI / device tree */ 1025 i2c_hid_fwnode_probe(client, &ihid->pdata); 1026 1027 ihid->pdata.supplies[0].supply = "vdd"; 1028 ihid->pdata.supplies[1].supply = "vddl"; 1029 1030 ret = devm_regulator_bulk_get(&client->dev, 1031 ARRAY_SIZE(ihid->pdata.supplies), 1032 ihid->pdata.supplies); 1033 if (ret) 1034 return ret; 1035 1036 ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies), 1037 ihid->pdata.supplies); 1038 if (ret < 0) 1039 return ret; 1040 1041 if (ihid->pdata.post_power_delay_ms) 1042 msleep(ihid->pdata.post_power_delay_ms); 1043 1044 i2c_set_clientdata(client, ihid); 1045 1046 ihid->client = client; 1047 1048 hidRegister = ihid->pdata.hid_descriptor_address; 1049 ihid->wHIDDescRegister = cpu_to_le16(hidRegister); 1050 1051 init_waitqueue_head(&ihid->wait); 1052 mutex_init(&ihid->reset_lock); 1053 1054 /* we need to allocate the command buffer without knowing the maximum 1055 * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the 1056 * real computation later. */ 1057 ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE); 1058 if (ret < 0) 1059 goto err_regulator; 1060 1061 i2c_hid_acpi_fix_up_power(&client->dev); 1062 1063 device_enable_async_suspend(&client->dev); 1064 1065 /* Make sure there is something at this address */ 1066 ret = i2c_smbus_read_byte(client); 1067 if (ret < 0) { 1068 dev_dbg(&client->dev, "nothing at this address: %d\n", ret); 1069 ret = -ENXIO; 1070 goto err_regulator; 1071 } 1072 1073 ret = i2c_hid_fetch_hid_descriptor(ihid); 1074 if (ret < 0) 1075 goto err_regulator; 1076 1077 ret = i2c_hid_init_irq(client); 1078 if (ret < 0) 1079 goto err_regulator; 1080 1081 hid = hid_allocate_device(); 1082 if (IS_ERR(hid)) { 1083 ret = PTR_ERR(hid); 1084 goto err_irq; 1085 } 1086 1087 ihid->hid = hid; 1088 1089 hid->driver_data = client; 1090 hid->ll_driver = &i2c_hid_ll_driver; 1091 hid->dev.parent = &client->dev; 1092 hid->bus = BUS_I2C; 1093 hid->version = le16_to_cpu(ihid->hdesc.bcdVersion); 1094 hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID); 1095 hid->product = le16_to_cpu(ihid->hdesc.wProductID); 1096 1097 snprintf(hid->name, sizeof(hid->name), "%s %04hX:%04hX", 1098 client->name, hid->vendor, hid->product); 1099 strlcpy(hid->phys, dev_name(&client->dev), sizeof(hid->phys)); 1100 1101 ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product); 1102 1103 ret = hid_add_device(hid); 1104 if (ret) { 1105 if (ret != -ENODEV) 1106 hid_err(client, "can't add hid device: %d\n", ret); 1107 goto err_mem_free; 1108 } 1109 1110 return 0; 1111 1112 err_mem_free: 1113 hid_destroy_device(hid); 1114 1115 err_irq: 1116 free_irq(client->irq, ihid); 1117 1118 err_regulator: 1119 regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies), 1120 ihid->pdata.supplies); 1121 i2c_hid_free_buffers(ihid); 1122 return ret; 1123 } 1124 1125 static int i2c_hid_remove(struct i2c_client *client) 1126 { 1127 struct i2c_hid *ihid = i2c_get_clientdata(client); 1128 struct hid_device *hid; 1129 1130 hid = ihid->hid; 1131 hid_destroy_device(hid); 1132 1133 free_irq(client->irq, ihid); 1134 1135 if (ihid->bufsize) 1136 i2c_hid_free_buffers(ihid); 1137 1138 regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies), 1139 ihid->pdata.supplies); 1140 1141 return 0; 1142 } 1143 1144 static void i2c_hid_shutdown(struct i2c_client *client) 1145 { 1146 struct i2c_hid *ihid = i2c_get_clientdata(client); 1147 1148 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); 1149 free_irq(client->irq, ihid); 1150 } 1151 1152 #ifdef CONFIG_PM_SLEEP 1153 static int i2c_hid_suspend(struct device *dev) 1154 { 1155 struct i2c_client *client = to_i2c_client(dev); 1156 struct i2c_hid *ihid = i2c_get_clientdata(client); 1157 struct hid_device *hid = ihid->hid; 1158 int ret; 1159 int wake_status; 1160 1161 if (hid->driver && hid->driver->suspend) { 1162 ret = hid->driver->suspend(hid, PMSG_SUSPEND); 1163 if (ret < 0) 1164 return ret; 1165 } 1166 1167 /* Save some power */ 1168 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); 1169 1170 disable_irq(client->irq); 1171 1172 if (device_may_wakeup(&client->dev)) { 1173 wake_status = enable_irq_wake(client->irq); 1174 if (!wake_status) 1175 ihid->irq_wake_enabled = true; 1176 else 1177 hid_warn(hid, "Failed to enable irq wake: %d\n", 1178 wake_status); 1179 } else { 1180 regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies), 1181 ihid->pdata.supplies); 1182 } 1183 1184 return 0; 1185 } 1186 1187 static int i2c_hid_resume(struct device *dev) 1188 { 1189 int ret; 1190 struct i2c_client *client = to_i2c_client(dev); 1191 struct i2c_hid *ihid = i2c_get_clientdata(client); 1192 struct hid_device *hid = ihid->hid; 1193 int wake_status; 1194 1195 if (!device_may_wakeup(&client->dev)) { 1196 ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies), 1197 ihid->pdata.supplies); 1198 if (ret) 1199 hid_warn(hid, "Failed to enable supplies: %d\n", ret); 1200 1201 if (ihid->pdata.post_power_delay_ms) 1202 msleep(ihid->pdata.post_power_delay_ms); 1203 } else if (ihid->irq_wake_enabled) { 1204 wake_status = disable_irq_wake(client->irq); 1205 if (!wake_status) 1206 ihid->irq_wake_enabled = false; 1207 else 1208 hid_warn(hid, "Failed to disable irq wake: %d\n", 1209 wake_status); 1210 } 1211 1212 enable_irq(client->irq); 1213 1214 /* Instead of resetting device, simply powers the device on. This 1215 * solves "incomplete reports" on Raydium devices 2386:3118 and 1216 * 2386:4B33 and fixes various SIS touchscreens no longer sending 1217 * data after a suspend/resume. 1218 * 1219 * However some ALPS touchpads generate IRQ storm without reset, so 1220 * let's still reset them here. 1221 */ 1222 if (ihid->quirks & I2C_HID_QUIRK_RESET_ON_RESUME) 1223 ret = i2c_hid_hwreset(client); 1224 else 1225 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON); 1226 1227 if (ret) 1228 return ret; 1229 1230 if (hid->driver && hid->driver->reset_resume) { 1231 ret = hid->driver->reset_resume(hid); 1232 return ret; 1233 } 1234 1235 return 0; 1236 } 1237 #endif 1238 1239 static const struct dev_pm_ops i2c_hid_pm = { 1240 SET_SYSTEM_SLEEP_PM_OPS(i2c_hid_suspend, i2c_hid_resume) 1241 }; 1242 1243 static const struct i2c_device_id i2c_hid_id_table[] = { 1244 { "hid", 0 }, 1245 { "hid-over-i2c", 0 }, 1246 { }, 1247 }; 1248 MODULE_DEVICE_TABLE(i2c, i2c_hid_id_table); 1249 1250 1251 static struct i2c_driver i2c_hid_driver = { 1252 .driver = { 1253 .name = "i2c_hid", 1254 .pm = &i2c_hid_pm, 1255 .acpi_match_table = ACPI_PTR(i2c_hid_acpi_match), 1256 .of_match_table = of_match_ptr(i2c_hid_of_match), 1257 }, 1258 1259 .probe = i2c_hid_probe, 1260 .remove = i2c_hid_remove, 1261 .shutdown = i2c_hid_shutdown, 1262 .id_table = i2c_hid_id_table, 1263 }; 1264 1265 module_i2c_driver(i2c_hid_driver); 1266 1267 MODULE_DESCRIPTION("HID over I2C core driver"); 1268 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>"); 1269 MODULE_LICENSE("GPL"); 1270