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 #define I2C_HID_QUIRK_BAD_INPUT_SIZE BIT(6) 53 54 55 /* flags */ 56 #define I2C_HID_STARTED 0 57 #define I2C_HID_RESET_PENDING 1 58 #define I2C_HID_READ_PENDING 2 59 60 #define I2C_HID_PWR_ON 0x00 61 #define I2C_HID_PWR_SLEEP 0x01 62 63 /* debug option */ 64 static bool debug; 65 module_param(debug, bool, 0444); 66 MODULE_PARM_DESC(debug, "print a lot of debug information"); 67 68 #define i2c_hid_dbg(ihid, fmt, arg...) \ 69 do { \ 70 if (debug) \ 71 dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \ 72 } while (0) 73 74 struct i2c_hid_desc { 75 __le16 wHIDDescLength; 76 __le16 bcdVersion; 77 __le16 wReportDescLength; 78 __le16 wReportDescRegister; 79 __le16 wInputRegister; 80 __le16 wMaxInputLength; 81 __le16 wOutputRegister; 82 __le16 wMaxOutputLength; 83 __le16 wCommandRegister; 84 __le16 wDataRegister; 85 __le16 wVendorID; 86 __le16 wProductID; 87 __le16 wVersionID; 88 __le32 reserved; 89 } __packed; 90 91 struct i2c_hid_cmd { 92 unsigned int registerIndex; 93 __u8 opcode; 94 unsigned int length; 95 bool wait; 96 }; 97 98 union command { 99 u8 data[0]; 100 struct cmd { 101 __le16 reg; 102 __u8 reportTypeID; 103 __u8 opcode; 104 } __packed c; 105 }; 106 107 #define I2C_HID_CMD(opcode_) \ 108 .opcode = opcode_, .length = 4, \ 109 .registerIndex = offsetof(struct i2c_hid_desc, wCommandRegister) 110 111 /* fetch HID descriptor */ 112 static const struct i2c_hid_cmd hid_descr_cmd = { .length = 2 }; 113 /* fetch report descriptors */ 114 static const struct i2c_hid_cmd hid_report_descr_cmd = { 115 .registerIndex = offsetof(struct i2c_hid_desc, 116 wReportDescRegister), 117 .opcode = 0x00, 118 .length = 2 }; 119 /* commands */ 120 static const struct i2c_hid_cmd hid_reset_cmd = { I2C_HID_CMD(0x01), 121 .wait = true }; 122 static const struct i2c_hid_cmd hid_get_report_cmd = { I2C_HID_CMD(0x02) }; 123 static const struct i2c_hid_cmd hid_set_report_cmd = { I2C_HID_CMD(0x03) }; 124 static const struct i2c_hid_cmd hid_set_power_cmd = { I2C_HID_CMD(0x08) }; 125 static const struct i2c_hid_cmd hid_no_cmd = { .length = 0 }; 126 127 /* 128 * These definitions are not used here, but are defined by the spec. 129 * Keeping them here for documentation purposes. 130 * 131 * static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) }; 132 * static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) }; 133 * static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) }; 134 * static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) }; 135 */ 136 137 /* The main device structure */ 138 struct i2c_hid { 139 struct i2c_client *client; /* i2c client */ 140 struct hid_device *hid; /* pointer to corresponding HID dev */ 141 union { 142 __u8 hdesc_buffer[sizeof(struct i2c_hid_desc)]; 143 struct i2c_hid_desc hdesc; /* the HID Descriptor */ 144 }; 145 __le16 wHIDDescRegister; /* location of the i2c 146 * register of the HID 147 * descriptor. */ 148 unsigned int bufsize; /* i2c buffer size */ 149 u8 *inbuf; /* Input buffer */ 150 u8 *rawbuf; /* Raw Input buffer */ 151 u8 *cmdbuf; /* Command buffer */ 152 u8 *argsbuf; /* Command arguments buffer */ 153 154 unsigned long flags; /* device flags */ 155 unsigned long quirks; /* Various quirks */ 156 157 wait_queue_head_t wait; /* For waiting the interrupt */ 158 159 struct i2c_hid_platform_data pdata; 160 161 bool irq_wake_enabled; 162 struct mutex reset_lock; 163 }; 164 165 static const struct i2c_hid_quirks { 166 __u16 idVendor; 167 __u16 idProduct; 168 __u32 quirks; 169 } i2c_hid_quirks[] = { 170 { USB_VENDOR_ID_WEIDA, HID_ANY_ID, 171 I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV }, 172 { I2C_VENDOR_ID_HANTICK, I2C_PRODUCT_ID_HANTICK_5288, 173 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET }, 174 { I2C_VENDOR_ID_RAYDIUM, I2C_PRODUCT_ID_RAYDIUM_3118, 175 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET }, 176 { USB_VENDOR_ID_ELAN, HID_ANY_ID, 177 I2C_HID_QUIRK_BOGUS_IRQ }, 178 { USB_VENDOR_ID_ALPS_JP, HID_ANY_ID, 179 I2C_HID_QUIRK_RESET_ON_RESUME }, 180 { I2C_VENDOR_ID_SYNAPTICS, I2C_PRODUCT_ID_SYNAPTICS_SYNA2393, 181 I2C_HID_QUIRK_RESET_ON_RESUME }, 182 { USB_VENDOR_ID_ITE, I2C_DEVICE_ID_ITE_LENOVO_LEGION_Y720, 183 I2C_HID_QUIRK_BAD_INPUT_SIZE }, 184 { 0, 0 } 185 }; 186 187 /* 188 * i2c_hid_lookup_quirk: return any quirks associated with a I2C HID device 189 * @idVendor: the 16-bit vendor ID 190 * @idProduct: the 16-bit product ID 191 * 192 * Returns: a u32 quirks value. 193 */ 194 static u32 i2c_hid_lookup_quirk(const u16 idVendor, const u16 idProduct) 195 { 196 u32 quirks = 0; 197 int n; 198 199 for (n = 0; i2c_hid_quirks[n].idVendor; n++) 200 if (i2c_hid_quirks[n].idVendor == idVendor && 201 (i2c_hid_quirks[n].idProduct == (__u16)HID_ANY_ID || 202 i2c_hid_quirks[n].idProduct == idProduct)) 203 quirks = i2c_hid_quirks[n].quirks; 204 205 return quirks; 206 } 207 208 static int __i2c_hid_command(struct i2c_client *client, 209 const struct i2c_hid_cmd *command, u8 reportID, 210 u8 reportType, u8 *args, int args_len, 211 unsigned char *buf_recv, int data_len) 212 { 213 struct i2c_hid *ihid = i2c_get_clientdata(client); 214 union command *cmd = (union command *)ihid->cmdbuf; 215 int ret; 216 struct i2c_msg msg[2]; 217 int msg_num = 1; 218 219 int length = command->length; 220 bool wait = command->wait; 221 unsigned int registerIndex = command->registerIndex; 222 223 /* special case for hid_descr_cmd */ 224 if (command == &hid_descr_cmd) { 225 cmd->c.reg = ihid->wHIDDescRegister; 226 } else { 227 cmd->data[0] = ihid->hdesc_buffer[registerIndex]; 228 cmd->data[1] = ihid->hdesc_buffer[registerIndex + 1]; 229 } 230 231 if (length > 2) { 232 cmd->c.opcode = command->opcode; 233 cmd->c.reportTypeID = reportID | reportType << 4; 234 } 235 236 memcpy(cmd->data + length, args, args_len); 237 length += args_len; 238 239 i2c_hid_dbg(ihid, "%s: cmd=%*ph\n", __func__, length, cmd->data); 240 241 msg[0].addr = client->addr; 242 msg[0].flags = client->flags & I2C_M_TEN; 243 msg[0].len = length; 244 msg[0].buf = cmd->data; 245 if (data_len > 0) { 246 msg[1].addr = client->addr; 247 msg[1].flags = client->flags & I2C_M_TEN; 248 msg[1].flags |= I2C_M_RD; 249 msg[1].len = data_len; 250 msg[1].buf = buf_recv; 251 msg_num = 2; 252 set_bit(I2C_HID_READ_PENDING, &ihid->flags); 253 } 254 255 if (wait) 256 set_bit(I2C_HID_RESET_PENDING, &ihid->flags); 257 258 ret = i2c_transfer(client->adapter, msg, msg_num); 259 260 if (data_len > 0) 261 clear_bit(I2C_HID_READ_PENDING, &ihid->flags); 262 263 if (ret != msg_num) 264 return ret < 0 ? ret : -EIO; 265 266 ret = 0; 267 268 if (wait && (ihid->quirks & I2C_HID_QUIRK_NO_IRQ_AFTER_RESET)) { 269 msleep(100); 270 } else if (wait) { 271 i2c_hid_dbg(ihid, "%s: waiting...\n", __func__); 272 if (!wait_event_timeout(ihid->wait, 273 !test_bit(I2C_HID_RESET_PENDING, &ihid->flags), 274 msecs_to_jiffies(5000))) 275 ret = -ENODATA; 276 i2c_hid_dbg(ihid, "%s: finished.\n", __func__); 277 } 278 279 return ret; 280 } 281 282 static int i2c_hid_command(struct i2c_client *client, 283 const struct i2c_hid_cmd *command, 284 unsigned char *buf_recv, int data_len) 285 { 286 return __i2c_hid_command(client, command, 0, 0, NULL, 0, 287 buf_recv, data_len); 288 } 289 290 static int i2c_hid_get_report(struct i2c_client *client, u8 reportType, 291 u8 reportID, unsigned char *buf_recv, int data_len) 292 { 293 struct i2c_hid *ihid = i2c_get_clientdata(client); 294 u8 args[3]; 295 int ret; 296 int args_len = 0; 297 u16 readRegister = le16_to_cpu(ihid->hdesc.wDataRegister); 298 299 i2c_hid_dbg(ihid, "%s\n", __func__); 300 301 if (reportID >= 0x0F) { 302 args[args_len++] = reportID; 303 reportID = 0x0F; 304 } 305 306 args[args_len++] = readRegister & 0xFF; 307 args[args_len++] = readRegister >> 8; 308 309 ret = __i2c_hid_command(client, &hid_get_report_cmd, reportID, 310 reportType, args, args_len, buf_recv, data_len); 311 if (ret) { 312 dev_err(&client->dev, 313 "failed to retrieve report from device.\n"); 314 return ret; 315 } 316 317 return 0; 318 } 319 320 /** 321 * i2c_hid_set_or_send_report: forward an incoming report to the device 322 * @client: the i2c_client of the device 323 * @reportType: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT 324 * @reportID: the report ID 325 * @buf: the actual data to transfer, without the report ID 326 * @data_len: size of buf 327 * @use_data: true: use SET_REPORT HID command, false: send plain OUTPUT report 328 */ 329 static int i2c_hid_set_or_send_report(struct i2c_client *client, u8 reportType, 330 u8 reportID, unsigned char *buf, size_t data_len, bool use_data) 331 { 332 struct i2c_hid *ihid = i2c_get_clientdata(client); 333 u8 *args = ihid->argsbuf; 334 const struct i2c_hid_cmd *hidcmd; 335 int ret; 336 u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister); 337 u16 outputRegister = le16_to_cpu(ihid->hdesc.wOutputRegister); 338 u16 maxOutputLength = le16_to_cpu(ihid->hdesc.wMaxOutputLength); 339 u16 size; 340 int args_len; 341 int index = 0; 342 343 i2c_hid_dbg(ihid, "%s\n", __func__); 344 345 if (data_len > ihid->bufsize) 346 return -EINVAL; 347 348 size = 2 /* size */ + 349 (reportID ? 1 : 0) /* reportID */ + 350 data_len /* buf */; 351 args_len = (reportID >= 0x0F ? 1 : 0) /* optional third byte */ + 352 2 /* dataRegister */ + 353 size /* args */; 354 355 if (!use_data && maxOutputLength == 0) 356 return -ENOSYS; 357 358 if (reportID >= 0x0F) { 359 args[index++] = reportID; 360 reportID = 0x0F; 361 } 362 363 /* 364 * use the data register for feature reports or if the device does not 365 * support the output register 366 */ 367 if (use_data) { 368 args[index++] = dataRegister & 0xFF; 369 args[index++] = dataRegister >> 8; 370 hidcmd = &hid_set_report_cmd; 371 } else { 372 args[index++] = outputRegister & 0xFF; 373 args[index++] = outputRegister >> 8; 374 hidcmd = &hid_no_cmd; 375 } 376 377 args[index++] = size & 0xFF; 378 args[index++] = size >> 8; 379 380 if (reportID) 381 args[index++] = reportID; 382 383 memcpy(&args[index], buf, data_len); 384 385 ret = __i2c_hid_command(client, hidcmd, reportID, 386 reportType, args, args_len, NULL, 0); 387 if (ret) { 388 dev_err(&client->dev, "failed to set a report to device.\n"); 389 return ret; 390 } 391 392 return data_len; 393 } 394 395 static int i2c_hid_set_power(struct i2c_client *client, int power_state) 396 { 397 struct i2c_hid *ihid = i2c_get_clientdata(client); 398 int ret; 399 400 i2c_hid_dbg(ihid, "%s\n", __func__); 401 402 /* 403 * Some devices require to send a command to wakeup before power on. 404 * The call will get a return value (EREMOTEIO) but device will be 405 * triggered and activated. After that, it goes like a normal device. 406 */ 407 if (power_state == I2C_HID_PWR_ON && 408 ihid->quirks & I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV) { 409 ret = i2c_hid_command(client, &hid_set_power_cmd, NULL, 0); 410 411 /* Device was already activated */ 412 if (!ret) 413 goto set_pwr_exit; 414 } 415 416 ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state, 417 0, NULL, 0, NULL, 0); 418 419 if (ret) 420 dev_err(&client->dev, "failed to change power setting.\n"); 421 422 set_pwr_exit: 423 424 /* 425 * The HID over I2C specification states that if a DEVICE needs time 426 * after the PWR_ON request, it should utilise CLOCK stretching. 427 * However, it has been observered that the Windows driver provides a 428 * 1ms sleep between the PWR_ON and RESET requests. 429 * According to Goodix Windows even waits 60 ms after (other?) 430 * PWR_ON requests. Testing has confirmed that several devices 431 * will not work properly without a delay after a PWR_ON request. 432 */ 433 if (!ret && power_state == I2C_HID_PWR_ON) 434 msleep(60); 435 436 return ret; 437 } 438 439 static int i2c_hid_hwreset(struct i2c_client *client) 440 { 441 struct i2c_hid *ihid = i2c_get_clientdata(client); 442 int ret; 443 444 i2c_hid_dbg(ihid, "%s\n", __func__); 445 446 /* 447 * This prevents sending feature reports while the device is 448 * being reset. Otherwise we may lose the reset complete 449 * interrupt. 450 */ 451 mutex_lock(&ihid->reset_lock); 452 453 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON); 454 if (ret) 455 goto out_unlock; 456 457 i2c_hid_dbg(ihid, "resetting...\n"); 458 459 ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0); 460 if (ret) { 461 dev_err(&client->dev, "failed to reset device.\n"); 462 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); 463 goto out_unlock; 464 } 465 466 /* At least some SIS devices need this after reset */ 467 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON); 468 469 out_unlock: 470 mutex_unlock(&ihid->reset_lock); 471 return ret; 472 } 473 474 static void i2c_hid_get_input(struct i2c_hid *ihid) 475 { 476 int ret; 477 u32 ret_size; 478 int size = le16_to_cpu(ihid->hdesc.wMaxInputLength); 479 480 if (size > ihid->bufsize) 481 size = ihid->bufsize; 482 483 ret = i2c_master_recv(ihid->client, ihid->inbuf, size); 484 if (ret != size) { 485 if (ret < 0) 486 return; 487 488 dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n", 489 __func__, ret, size); 490 return; 491 } 492 493 ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8; 494 495 if (!ret_size) { 496 /* host or device initiated RESET completed */ 497 if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags)) 498 wake_up(&ihid->wait); 499 return; 500 } 501 502 if (ihid->quirks & I2C_HID_QUIRK_BOGUS_IRQ && ret_size == 0xffff) { 503 dev_warn_once(&ihid->client->dev, "%s: IRQ triggered but " 504 "there's no data\n", __func__); 505 return; 506 } 507 508 if ((ret_size > size) || (ret_size < 2)) { 509 if (ihid->quirks & I2C_HID_QUIRK_BAD_INPUT_SIZE) { 510 ihid->inbuf[0] = size & 0xff; 511 ihid->inbuf[1] = size >> 8; 512 ret_size = size; 513 } else { 514 dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n", 515 __func__, size, ret_size); 516 return; 517 } 518 } 519 520 i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf); 521 522 if (test_bit(I2C_HID_STARTED, &ihid->flags)) 523 hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2, 524 ret_size - 2, 1); 525 526 return; 527 } 528 529 static irqreturn_t i2c_hid_irq(int irq, void *dev_id) 530 { 531 struct i2c_hid *ihid = dev_id; 532 533 if (test_bit(I2C_HID_READ_PENDING, &ihid->flags)) 534 return IRQ_HANDLED; 535 536 i2c_hid_get_input(ihid); 537 538 return IRQ_HANDLED; 539 } 540 541 static int i2c_hid_get_report_length(struct hid_report *report) 542 { 543 return ((report->size - 1) >> 3) + 1 + 544 report->device->report_enum[report->type].numbered + 2; 545 } 546 547 /* 548 * Traverse the supplied list of reports and find the longest 549 */ 550 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type, 551 unsigned int *max) 552 { 553 struct hid_report *report; 554 unsigned int size; 555 556 /* We should not rely on wMaxInputLength, as some devices may set it to 557 * a wrong length. */ 558 list_for_each_entry(report, &hid->report_enum[type].report_list, list) { 559 size = i2c_hid_get_report_length(report); 560 if (*max < size) 561 *max = size; 562 } 563 } 564 565 static void i2c_hid_free_buffers(struct i2c_hid *ihid) 566 { 567 kfree(ihid->inbuf); 568 kfree(ihid->rawbuf); 569 kfree(ihid->argsbuf); 570 kfree(ihid->cmdbuf); 571 ihid->inbuf = NULL; 572 ihid->rawbuf = NULL; 573 ihid->cmdbuf = NULL; 574 ihid->argsbuf = NULL; 575 ihid->bufsize = 0; 576 } 577 578 static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size) 579 { 580 /* the worst case is computed from the set_report command with a 581 * reportID > 15 and the maximum report length */ 582 int args_len = sizeof(__u8) + /* ReportID */ 583 sizeof(__u8) + /* optional ReportID byte */ 584 sizeof(__u16) + /* data register */ 585 sizeof(__u16) + /* size of the report */ 586 report_size; /* report */ 587 588 ihid->inbuf = kzalloc(report_size, GFP_KERNEL); 589 ihid->rawbuf = kzalloc(report_size, GFP_KERNEL); 590 ihid->argsbuf = kzalloc(args_len, GFP_KERNEL); 591 ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL); 592 593 if (!ihid->inbuf || !ihid->rawbuf || !ihid->argsbuf || !ihid->cmdbuf) { 594 i2c_hid_free_buffers(ihid); 595 return -ENOMEM; 596 } 597 598 ihid->bufsize = report_size; 599 600 return 0; 601 } 602 603 static int i2c_hid_get_raw_report(struct hid_device *hid, 604 unsigned char report_number, __u8 *buf, size_t count, 605 unsigned char report_type) 606 { 607 struct i2c_client *client = hid->driver_data; 608 struct i2c_hid *ihid = i2c_get_clientdata(client); 609 size_t ret_count, ask_count; 610 int ret; 611 612 if (report_type == HID_OUTPUT_REPORT) 613 return -EINVAL; 614 615 /* +2 bytes to include the size of the reply in the query buffer */ 616 ask_count = min(count + 2, (size_t)ihid->bufsize); 617 618 ret = i2c_hid_get_report(client, 619 report_type == HID_FEATURE_REPORT ? 0x03 : 0x01, 620 report_number, ihid->rawbuf, ask_count); 621 622 if (ret < 0) 623 return ret; 624 625 ret_count = ihid->rawbuf[0] | (ihid->rawbuf[1] << 8); 626 627 if (ret_count <= 2) 628 return 0; 629 630 ret_count = min(ret_count, ask_count); 631 632 /* The query buffer contains the size, dropping it in the reply */ 633 count = min(count, ret_count - 2); 634 memcpy(buf, ihid->rawbuf + 2, count); 635 636 return count; 637 } 638 639 static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf, 640 size_t count, unsigned char report_type, bool use_data) 641 { 642 struct i2c_client *client = hid->driver_data; 643 struct i2c_hid *ihid = i2c_get_clientdata(client); 644 int report_id = buf[0]; 645 int ret; 646 647 if (report_type == HID_INPUT_REPORT) 648 return -EINVAL; 649 650 mutex_lock(&ihid->reset_lock); 651 652 if (report_id) { 653 buf++; 654 count--; 655 } 656 657 ret = i2c_hid_set_or_send_report(client, 658 report_type == HID_FEATURE_REPORT ? 0x03 : 0x02, 659 report_id, buf, count, use_data); 660 661 if (report_id && ret >= 0) 662 ret++; /* add report_id to the number of transfered bytes */ 663 664 mutex_unlock(&ihid->reset_lock); 665 666 return ret; 667 } 668 669 static int i2c_hid_output_report(struct hid_device *hid, __u8 *buf, 670 size_t count) 671 { 672 return i2c_hid_output_raw_report(hid, buf, count, HID_OUTPUT_REPORT, 673 false); 674 } 675 676 static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum, 677 __u8 *buf, size_t len, unsigned char rtype, 678 int reqtype) 679 { 680 switch (reqtype) { 681 case HID_REQ_GET_REPORT: 682 return i2c_hid_get_raw_report(hid, reportnum, buf, len, rtype); 683 case HID_REQ_SET_REPORT: 684 if (buf[0] != reportnum) 685 return -EINVAL; 686 return i2c_hid_output_raw_report(hid, buf, len, rtype, true); 687 default: 688 return -EIO; 689 } 690 } 691 692 static int i2c_hid_parse(struct hid_device *hid) 693 { 694 struct i2c_client *client = hid->driver_data; 695 struct i2c_hid *ihid = i2c_get_clientdata(client); 696 struct i2c_hid_desc *hdesc = &ihid->hdesc; 697 unsigned int rsize; 698 char *rdesc; 699 int ret; 700 int tries = 3; 701 char *use_override; 702 703 i2c_hid_dbg(ihid, "entering %s\n", __func__); 704 705 rsize = le16_to_cpu(hdesc->wReportDescLength); 706 if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) { 707 dbg_hid("weird size of report descriptor (%u)\n", rsize); 708 return -EINVAL; 709 } 710 711 do { 712 ret = i2c_hid_hwreset(client); 713 if (ret) 714 msleep(1000); 715 } while (tries-- > 0 && ret); 716 717 if (ret) 718 return ret; 719 720 use_override = i2c_hid_get_dmi_hid_report_desc_override(client->name, 721 &rsize); 722 723 if (use_override) { 724 rdesc = use_override; 725 i2c_hid_dbg(ihid, "Using a HID report descriptor override\n"); 726 } else { 727 rdesc = kzalloc(rsize, GFP_KERNEL); 728 729 if (!rdesc) { 730 dbg_hid("couldn't allocate rdesc memory\n"); 731 return -ENOMEM; 732 } 733 734 i2c_hid_dbg(ihid, "asking HID report descriptor\n"); 735 736 ret = i2c_hid_command(client, &hid_report_descr_cmd, 737 rdesc, rsize); 738 if (ret) { 739 hid_err(hid, "reading report descriptor failed\n"); 740 kfree(rdesc); 741 return -EIO; 742 } 743 } 744 745 i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc); 746 747 ret = hid_parse_report(hid, rdesc, rsize); 748 if (!use_override) 749 kfree(rdesc); 750 751 if (ret) { 752 dbg_hid("parsing report descriptor failed\n"); 753 return ret; 754 } 755 756 return 0; 757 } 758 759 static int i2c_hid_start(struct hid_device *hid) 760 { 761 struct i2c_client *client = hid->driver_data; 762 struct i2c_hid *ihid = i2c_get_clientdata(client); 763 int ret; 764 unsigned int bufsize = HID_MIN_BUFFER_SIZE; 765 766 i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize); 767 i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize); 768 i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize); 769 770 if (bufsize > ihid->bufsize) { 771 disable_irq(client->irq); 772 i2c_hid_free_buffers(ihid); 773 774 ret = i2c_hid_alloc_buffers(ihid, bufsize); 775 enable_irq(client->irq); 776 777 if (ret) 778 return ret; 779 } 780 781 return 0; 782 } 783 784 static void i2c_hid_stop(struct hid_device *hid) 785 { 786 hid->claimed = 0; 787 } 788 789 static int i2c_hid_open(struct hid_device *hid) 790 { 791 struct i2c_client *client = hid->driver_data; 792 struct i2c_hid *ihid = i2c_get_clientdata(client); 793 794 set_bit(I2C_HID_STARTED, &ihid->flags); 795 return 0; 796 } 797 798 static void i2c_hid_close(struct hid_device *hid) 799 { 800 struct i2c_client *client = hid->driver_data; 801 struct i2c_hid *ihid = i2c_get_clientdata(client); 802 803 clear_bit(I2C_HID_STARTED, &ihid->flags); 804 } 805 806 struct hid_ll_driver i2c_hid_ll_driver = { 807 .parse = i2c_hid_parse, 808 .start = i2c_hid_start, 809 .stop = i2c_hid_stop, 810 .open = i2c_hid_open, 811 .close = i2c_hid_close, 812 .output_report = i2c_hid_output_report, 813 .raw_request = i2c_hid_raw_request, 814 }; 815 EXPORT_SYMBOL_GPL(i2c_hid_ll_driver); 816 817 static int i2c_hid_init_irq(struct i2c_client *client) 818 { 819 struct i2c_hid *ihid = i2c_get_clientdata(client); 820 unsigned long irqflags = 0; 821 int ret; 822 823 dev_dbg(&client->dev, "Requesting IRQ: %d\n", client->irq); 824 825 if (!irq_get_trigger_type(client->irq)) 826 irqflags = IRQF_TRIGGER_LOW; 827 828 ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq, 829 irqflags | IRQF_ONESHOT, client->name, ihid); 830 if (ret < 0) { 831 dev_warn(&client->dev, 832 "Could not register for %s interrupt, irq = %d," 833 " ret = %d\n", 834 client->name, client->irq, ret); 835 836 return ret; 837 } 838 839 return 0; 840 } 841 842 static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid) 843 { 844 struct i2c_client *client = ihid->client; 845 struct i2c_hid_desc *hdesc = &ihid->hdesc; 846 unsigned int dsize; 847 int ret; 848 849 /* i2c hid fetch using a fixed descriptor size (30 bytes) */ 850 if (i2c_hid_get_dmi_i2c_hid_desc_override(client->name)) { 851 i2c_hid_dbg(ihid, "Using a HID descriptor override\n"); 852 ihid->hdesc = 853 *i2c_hid_get_dmi_i2c_hid_desc_override(client->name); 854 } else { 855 i2c_hid_dbg(ihid, "Fetching the HID descriptor\n"); 856 ret = i2c_hid_command(client, &hid_descr_cmd, 857 ihid->hdesc_buffer, 858 sizeof(struct i2c_hid_desc)); 859 if (ret) { 860 dev_err(&client->dev, "hid_descr_cmd failed\n"); 861 return -ENODEV; 862 } 863 } 864 865 /* Validate the length of HID descriptor, the 4 first bytes: 866 * bytes 0-1 -> length 867 * bytes 2-3 -> bcdVersion (has to be 1.00) */ 868 /* check bcdVersion == 1.0 */ 869 if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) { 870 dev_err(&client->dev, 871 "unexpected HID descriptor bcdVersion (0x%04hx)\n", 872 le16_to_cpu(hdesc->bcdVersion)); 873 return -ENODEV; 874 } 875 876 /* Descriptor length should be 30 bytes as per the specification */ 877 dsize = le16_to_cpu(hdesc->wHIDDescLength); 878 if (dsize != sizeof(struct i2c_hid_desc)) { 879 dev_err(&client->dev, "weird size of HID descriptor (%u)\n", 880 dsize); 881 return -ENODEV; 882 } 883 i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer); 884 return 0; 885 } 886 887 #ifdef CONFIG_ACPI 888 static const struct acpi_device_id i2c_hid_acpi_blacklist[] = { 889 /* 890 * The CHPN0001 ACPI device, which is used to describe the Chipone 891 * ICN8505 controller, has a _CID of PNP0C50 but is not HID compatible. 892 */ 893 {"CHPN0001", 0 }, 894 { }, 895 }; 896 897 static int i2c_hid_acpi_pdata(struct i2c_client *client, 898 struct i2c_hid_platform_data *pdata) 899 { 900 static guid_t i2c_hid_guid = 901 GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555, 902 0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE); 903 union acpi_object *obj; 904 struct acpi_device *adev; 905 acpi_handle handle; 906 907 handle = ACPI_HANDLE(&client->dev); 908 if (!handle || acpi_bus_get_device(handle, &adev)) { 909 dev_err(&client->dev, "Error could not get ACPI device\n"); 910 return -ENODEV; 911 } 912 913 if (acpi_match_device_ids(adev, i2c_hid_acpi_blacklist) == 0) 914 return -ENODEV; 915 916 obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL, 917 ACPI_TYPE_INTEGER); 918 if (!obj) { 919 dev_err(&client->dev, "Error _DSM call to get HID descriptor address failed\n"); 920 return -ENODEV; 921 } 922 923 pdata->hid_descriptor_address = obj->integer.value; 924 ACPI_FREE(obj); 925 926 return 0; 927 } 928 929 static void i2c_hid_acpi_fix_up_power(struct device *dev) 930 { 931 struct acpi_device *adev; 932 933 adev = ACPI_COMPANION(dev); 934 if (adev) 935 acpi_device_fix_up_power(adev); 936 } 937 938 static void i2c_hid_acpi_enable_wakeup(struct device *dev) 939 { 940 if (acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0) { 941 device_set_wakeup_capable(dev, true); 942 device_set_wakeup_enable(dev, false); 943 } 944 } 945 946 static void i2c_hid_acpi_shutdown(struct device *dev) 947 { 948 acpi_device_set_power(ACPI_COMPANION(dev), ACPI_STATE_D3_COLD); 949 } 950 951 static const struct acpi_device_id i2c_hid_acpi_match[] = { 952 {"ACPI0C50", 0 }, 953 {"PNP0C50", 0 }, 954 { }, 955 }; 956 MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match); 957 #else 958 static inline int i2c_hid_acpi_pdata(struct i2c_client *client, 959 struct i2c_hid_platform_data *pdata) 960 { 961 return -ENODEV; 962 } 963 964 static inline void i2c_hid_acpi_fix_up_power(struct device *dev) {} 965 966 static inline void i2c_hid_acpi_enable_wakeup(struct device *dev) {} 967 968 static inline void i2c_hid_acpi_shutdown(struct device *dev) {} 969 #endif 970 971 #ifdef CONFIG_OF 972 static int i2c_hid_of_probe(struct i2c_client *client, 973 struct i2c_hid_platform_data *pdata) 974 { 975 struct device *dev = &client->dev; 976 u32 val; 977 int ret; 978 979 ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val); 980 if (ret) { 981 dev_err(&client->dev, "HID register address not provided\n"); 982 return -ENODEV; 983 } 984 if (val >> 16) { 985 dev_err(&client->dev, "Bad HID register address: 0x%08x\n", 986 val); 987 return -EINVAL; 988 } 989 pdata->hid_descriptor_address = val; 990 991 return 0; 992 } 993 994 static const struct of_device_id i2c_hid_of_match[] = { 995 { .compatible = "hid-over-i2c" }, 996 {}, 997 }; 998 MODULE_DEVICE_TABLE(of, i2c_hid_of_match); 999 #else 1000 static inline int i2c_hid_of_probe(struct i2c_client *client, 1001 struct i2c_hid_platform_data *pdata) 1002 { 1003 return -ENODEV; 1004 } 1005 #endif 1006 1007 static void i2c_hid_fwnode_probe(struct i2c_client *client, 1008 struct i2c_hid_platform_data *pdata) 1009 { 1010 u32 val; 1011 1012 if (!device_property_read_u32(&client->dev, "post-power-on-delay-ms", 1013 &val)) 1014 pdata->post_power_delay_ms = val; 1015 } 1016 1017 static int i2c_hid_probe(struct i2c_client *client, 1018 const struct i2c_device_id *dev_id) 1019 { 1020 int ret; 1021 struct i2c_hid *ihid; 1022 struct hid_device *hid; 1023 __u16 hidRegister; 1024 struct i2c_hid_platform_data *platform_data = client->dev.platform_data; 1025 1026 dbg_hid("HID probe called for i2c 0x%02x\n", client->addr); 1027 1028 if (!client->irq) { 1029 dev_err(&client->dev, 1030 "HID over i2c has not been provided an Int IRQ\n"); 1031 return -EINVAL; 1032 } 1033 1034 if (client->irq < 0) { 1035 if (client->irq != -EPROBE_DEFER) 1036 dev_err(&client->dev, 1037 "HID over i2c doesn't have a valid IRQ\n"); 1038 return client->irq; 1039 } 1040 1041 ihid = devm_kzalloc(&client->dev, sizeof(*ihid), GFP_KERNEL); 1042 if (!ihid) 1043 return -ENOMEM; 1044 1045 if (client->dev.of_node) { 1046 ret = i2c_hid_of_probe(client, &ihid->pdata); 1047 if (ret) 1048 return ret; 1049 } else if (!platform_data) { 1050 ret = i2c_hid_acpi_pdata(client, &ihid->pdata); 1051 if (ret) 1052 return ret; 1053 } else { 1054 ihid->pdata = *platform_data; 1055 } 1056 1057 /* Parse platform agnostic common properties from ACPI / device tree */ 1058 i2c_hid_fwnode_probe(client, &ihid->pdata); 1059 1060 ihid->pdata.supplies[0].supply = "vdd"; 1061 ihid->pdata.supplies[1].supply = "vddl"; 1062 1063 ret = devm_regulator_bulk_get(&client->dev, 1064 ARRAY_SIZE(ihid->pdata.supplies), 1065 ihid->pdata.supplies); 1066 if (ret) 1067 return ret; 1068 1069 ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies), 1070 ihid->pdata.supplies); 1071 if (ret < 0) 1072 return ret; 1073 1074 if (ihid->pdata.post_power_delay_ms) 1075 msleep(ihid->pdata.post_power_delay_ms); 1076 1077 i2c_set_clientdata(client, ihid); 1078 1079 ihid->client = client; 1080 1081 hidRegister = ihid->pdata.hid_descriptor_address; 1082 ihid->wHIDDescRegister = cpu_to_le16(hidRegister); 1083 1084 init_waitqueue_head(&ihid->wait); 1085 mutex_init(&ihid->reset_lock); 1086 1087 /* we need to allocate the command buffer without knowing the maximum 1088 * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the 1089 * real computation later. */ 1090 ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE); 1091 if (ret < 0) 1092 goto err_regulator; 1093 1094 i2c_hid_acpi_fix_up_power(&client->dev); 1095 1096 i2c_hid_acpi_enable_wakeup(&client->dev); 1097 1098 device_enable_async_suspend(&client->dev); 1099 1100 /* Make sure there is something at this address */ 1101 ret = i2c_smbus_read_byte(client); 1102 if (ret < 0) { 1103 dev_dbg(&client->dev, "nothing at this address: %d\n", ret); 1104 ret = -ENXIO; 1105 goto err_regulator; 1106 } 1107 1108 ret = i2c_hid_fetch_hid_descriptor(ihid); 1109 if (ret < 0) { 1110 dev_err(&client->dev, 1111 "Failed to fetch the HID Descriptor\n"); 1112 goto err_regulator; 1113 } 1114 1115 ret = i2c_hid_init_irq(client); 1116 if (ret < 0) 1117 goto err_regulator; 1118 1119 hid = hid_allocate_device(); 1120 if (IS_ERR(hid)) { 1121 ret = PTR_ERR(hid); 1122 goto err_irq; 1123 } 1124 1125 ihid->hid = hid; 1126 1127 hid->driver_data = client; 1128 hid->ll_driver = &i2c_hid_ll_driver; 1129 hid->dev.parent = &client->dev; 1130 hid->bus = BUS_I2C; 1131 hid->version = le16_to_cpu(ihid->hdesc.bcdVersion); 1132 hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID); 1133 hid->product = le16_to_cpu(ihid->hdesc.wProductID); 1134 1135 snprintf(hid->name, sizeof(hid->name), "%s %04hX:%04hX", 1136 client->name, hid->vendor, hid->product); 1137 strlcpy(hid->phys, dev_name(&client->dev), sizeof(hid->phys)); 1138 1139 ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product); 1140 1141 ret = hid_add_device(hid); 1142 if (ret) { 1143 if (ret != -ENODEV) 1144 hid_err(client, "can't add hid device: %d\n", ret); 1145 goto err_mem_free; 1146 } 1147 1148 return 0; 1149 1150 err_mem_free: 1151 hid_destroy_device(hid); 1152 1153 err_irq: 1154 free_irq(client->irq, ihid); 1155 1156 err_regulator: 1157 regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies), 1158 ihid->pdata.supplies); 1159 i2c_hid_free_buffers(ihid); 1160 return ret; 1161 } 1162 1163 static int i2c_hid_remove(struct i2c_client *client) 1164 { 1165 struct i2c_hid *ihid = i2c_get_clientdata(client); 1166 struct hid_device *hid; 1167 1168 hid = ihid->hid; 1169 hid_destroy_device(hid); 1170 1171 free_irq(client->irq, ihid); 1172 1173 if (ihid->bufsize) 1174 i2c_hid_free_buffers(ihid); 1175 1176 regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies), 1177 ihid->pdata.supplies); 1178 1179 return 0; 1180 } 1181 1182 static void i2c_hid_shutdown(struct i2c_client *client) 1183 { 1184 struct i2c_hid *ihid = i2c_get_clientdata(client); 1185 1186 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); 1187 free_irq(client->irq, ihid); 1188 1189 i2c_hid_acpi_shutdown(&client->dev); 1190 } 1191 1192 #ifdef CONFIG_PM_SLEEP 1193 static int i2c_hid_suspend(struct device *dev) 1194 { 1195 struct i2c_client *client = to_i2c_client(dev); 1196 struct i2c_hid *ihid = i2c_get_clientdata(client); 1197 struct hid_device *hid = ihid->hid; 1198 int ret; 1199 int wake_status; 1200 1201 if (hid->driver && hid->driver->suspend) { 1202 ret = hid->driver->suspend(hid, PMSG_SUSPEND); 1203 if (ret < 0) 1204 return ret; 1205 } 1206 1207 /* Save some power */ 1208 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); 1209 1210 disable_irq(client->irq); 1211 1212 if (device_may_wakeup(&client->dev)) { 1213 wake_status = enable_irq_wake(client->irq); 1214 if (!wake_status) 1215 ihid->irq_wake_enabled = true; 1216 else 1217 hid_warn(hid, "Failed to enable irq wake: %d\n", 1218 wake_status); 1219 } else { 1220 regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies), 1221 ihid->pdata.supplies); 1222 } 1223 1224 return 0; 1225 } 1226 1227 static int i2c_hid_resume(struct device *dev) 1228 { 1229 int ret; 1230 struct i2c_client *client = to_i2c_client(dev); 1231 struct i2c_hid *ihid = i2c_get_clientdata(client); 1232 struct hid_device *hid = ihid->hid; 1233 int wake_status; 1234 1235 if (!device_may_wakeup(&client->dev)) { 1236 ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies), 1237 ihid->pdata.supplies); 1238 if (ret) 1239 hid_warn(hid, "Failed to enable supplies: %d\n", ret); 1240 1241 if (ihid->pdata.post_power_delay_ms) 1242 msleep(ihid->pdata.post_power_delay_ms); 1243 } else if (ihid->irq_wake_enabled) { 1244 wake_status = disable_irq_wake(client->irq); 1245 if (!wake_status) 1246 ihid->irq_wake_enabled = false; 1247 else 1248 hid_warn(hid, "Failed to disable irq wake: %d\n", 1249 wake_status); 1250 } 1251 1252 enable_irq(client->irq); 1253 1254 /* Instead of resetting device, simply powers the device on. This 1255 * solves "incomplete reports" on Raydium devices 2386:3118 and 1256 * 2386:4B33 and fixes various SIS touchscreens no longer sending 1257 * data after a suspend/resume. 1258 * 1259 * However some ALPS touchpads generate IRQ storm without reset, so 1260 * let's still reset them here. 1261 */ 1262 if (ihid->quirks & I2C_HID_QUIRK_RESET_ON_RESUME) 1263 ret = i2c_hid_hwreset(client); 1264 else 1265 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON); 1266 1267 if (ret) 1268 return ret; 1269 1270 if (hid->driver && hid->driver->reset_resume) { 1271 ret = hid->driver->reset_resume(hid); 1272 return ret; 1273 } 1274 1275 return 0; 1276 } 1277 #endif 1278 1279 static const struct dev_pm_ops i2c_hid_pm = { 1280 SET_SYSTEM_SLEEP_PM_OPS(i2c_hid_suspend, i2c_hid_resume) 1281 }; 1282 1283 static const struct i2c_device_id i2c_hid_id_table[] = { 1284 { "hid", 0 }, 1285 { "hid-over-i2c", 0 }, 1286 { }, 1287 }; 1288 MODULE_DEVICE_TABLE(i2c, i2c_hid_id_table); 1289 1290 1291 static struct i2c_driver i2c_hid_driver = { 1292 .driver = { 1293 .name = "i2c_hid", 1294 .pm = &i2c_hid_pm, 1295 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 1296 .acpi_match_table = ACPI_PTR(i2c_hid_acpi_match), 1297 .of_match_table = of_match_ptr(i2c_hid_of_match), 1298 }, 1299 1300 .probe = i2c_hid_probe, 1301 .remove = i2c_hid_remove, 1302 .shutdown = i2c_hid_shutdown, 1303 .id_table = i2c_hid_id_table, 1304 }; 1305 1306 module_i2c_driver(i2c_hid_driver); 1307 1308 MODULE_DESCRIPTION("HID over I2C core driver"); 1309 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>"); 1310 MODULE_LICENSE("GPL"); 1311