1 /** @file 2 This file implements I2C Host Protocol which provides callers with the ability to 3 do I/O transactions to all of the devices on the I2C bus. 4 5 Copyright (c) 2014, Hewlett-Packard Development Company, L.P.<BR> 6 Copyright (c) 2013 - 2015, Intel Corporation. All rights reserved.<BR> 7 This program and the accompanying materials 8 are licensed and made available under the terms and conditions of the BSD License 9 which accompanies this distribution. The full text of the license may be found at 10 http://opensource.org/licenses/bsd-license.php 11 12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 13 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 14 15 **/ 16 17 #include "I2cDxe.h" 18 19 EFI_DRIVER_BINDING_PROTOCOL gI2cHostDriverBinding = { 20 I2cHostDriverSupported, 21 I2cHostDriverStart, 22 I2cHostDriverStop, 23 0x10, 24 NULL, 25 NULL 26 }; 27 28 // 29 // Driver name table 30 // 31 GLOBAL_REMOVE_IF_UNREFERENCED EFI_UNICODE_STRING_TABLE mI2cHostDriverNameTable[] = { 32 { "eng;en", L"I2c Host Driver" }, 33 { NULL , NULL } 34 }; 35 36 // 37 // EFI Component Name Protocol 38 // 39 GLOBAL_REMOVE_IF_UNREFERENCED EFI_COMPONENT_NAME_PROTOCOL gI2cHostComponentName = { 40 (EFI_COMPONENT_NAME_GET_DRIVER_NAME) I2cHostComponentNameGetDriverName, 41 (EFI_COMPONENT_NAME_GET_CONTROLLER_NAME) I2cHostComponentNameGetControllerName, 42 "eng" 43 }; 44 45 // 46 // EFI Component Name 2 Protocol 47 // 48 GLOBAL_REMOVE_IF_UNREFERENCED EFI_COMPONENT_NAME2_PROTOCOL gI2cHostComponentName2 = { 49 I2cHostComponentNameGetDriverName, 50 I2cHostComponentNameGetControllerName, 51 "en" 52 }; 53 54 /** 55 Retrieves a Unicode string that is the user readable name of the driver. 56 57 This function retrieves the user readable name of a driver in the form of a 58 Unicode string. If the driver specified by This has a user readable name in 59 the language specified by Language, then a pointer to the driver name is 60 returned in DriverName, and EFI_SUCCESS is returned. If the driver specified 61 by This does not support the language specified by Language, 62 then EFI_UNSUPPORTED is returned. 63 64 @param This[in] A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or 65 EFI_COMPONENT_NAME_PROTOCOL instance. 66 67 @param Language[in] A pointer to a Null-terminated ASCII string 68 array indicating the language. This is the 69 language of the driver name that the caller is 70 requesting, and it must match one of the 71 languages specified in SupportedLanguages. The 72 number of languages supported by a driver is up 73 to the driver writer. Language is specified 74 in RFC 4646 or ISO 639-2 language code format. 75 76 @param DriverName[out] A pointer to the Unicode string to return. 77 This Unicode string is the name of the 78 driver specified by This in the language 79 specified by Language. 80 81 @retval EFI_SUCCESS The Unicode string for the Driver specified by 82 This and the language specified by Language was 83 returned in DriverName. 84 85 @retval EFI_INVALID_PARAMETER Language is NULL. 86 87 @retval EFI_INVALID_PARAMETER DriverName is NULL. 88 89 @retval EFI_UNSUPPORTED The driver specified by This does not support 90 the language specified by Language. 91 92 **/ 93 EFI_STATUS 94 EFIAPI 95 I2cHostComponentNameGetDriverName ( 96 IN EFI_COMPONENT_NAME2_PROTOCOL *This, 97 IN CHAR8 *Language, 98 OUT CHAR16 **DriverName 99 ) 100 { 101 return LookupUnicodeString2 ( 102 Language, 103 This->SupportedLanguages, 104 mI2cHostDriverNameTable, 105 DriverName, 106 (BOOLEAN)(This != &gI2cHostComponentName2) 107 ); 108 } 109 110 /** 111 Retrieves a Unicode string that is the user readable name of the controller 112 that is being managed by a driver. 113 114 This function retrieves the user readable name of the controller specified by 115 ControllerHandle and ChildHandle in the form of a Unicode string. If the 116 driver specified by This has a user readable name in the language specified by 117 Language, then a pointer to the controller name is returned in ControllerName, 118 and EFI_SUCCESS is returned. If the driver specified by This is not currently 119 managing the controller specified by ControllerHandle and ChildHandle, 120 then EFI_UNSUPPORTED is returned. If the driver specified by This does not 121 support the language specified by Language, then EFI_UNSUPPORTED is returned. 122 123 @param This[in] A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or 124 EFI_COMPONENT_NAME_PROTOCOL instance. 125 126 @param ControllerHandle[in] The handle of a controller that the driver 127 specified by This is managing. This handle 128 specifies the controller whose name is to be 129 returned. 130 131 @param ChildHandle[in] The handle of the child controller to retrieve 132 the name of. This is an optional parameter that 133 may be NULL. It will be NULL for device 134 drivers. It will also be NULL for a bus drivers 135 that wish to retrieve the name of the bus 136 controller. It will not be NULL for a bus 137 driver that wishes to retrieve the name of a 138 child controller. 139 140 @param Language[in] A pointer to a Null-terminated ASCII string 141 array indicating the language. This is the 142 language of the driver name that the caller is 143 requesting, and it must match one of the 144 languages specified in SupportedLanguages. The 145 number of languages supported by a driver is up 146 to the driver writer. Language is specified in 147 RFC 4646 or ISO 639-2 language code format. 148 149 @param ControllerName[out] A pointer to the Unicode string to return. 150 This Unicode string is the name of the 151 controller specified by ControllerHandle and 152 ChildHandle in the language specified by 153 Language from the point of view of the driver 154 specified by This. 155 156 @retval EFI_SUCCESS The Unicode string for the user readable name in 157 the language specified by Language for the 158 driver specified by This was returned in 159 DriverName. 160 161 @retval EFI_INVALID_PARAMETER ControllerHandle is NULL. 162 163 @retval EFI_INVALID_PARAMETER ChildHandle is not NULL and it is not a valid 164 EFI_HANDLE. 165 166 @retval EFI_INVALID_PARAMETER Language is NULL. 167 168 @retval EFI_INVALID_PARAMETER ControllerName is NULL. 169 170 @retval EFI_UNSUPPORTED The driver specified by This is not currently 171 managing the controller specified by 172 ControllerHandle and ChildHandle. 173 174 @retval EFI_UNSUPPORTED The driver specified by This does not support 175 the language specified by Language. 176 177 **/ 178 EFI_STATUS 179 EFIAPI 180 I2cHostComponentNameGetControllerName ( 181 IN EFI_COMPONENT_NAME2_PROTOCOL *This, 182 IN EFI_HANDLE ControllerHandle, 183 IN EFI_HANDLE ChildHandle OPTIONAL, 184 IN CHAR8 *Language, 185 OUT CHAR16 **ControllerName 186 ) 187 { 188 return EFI_UNSUPPORTED; 189 } 190 191 /** 192 Tests to see if this driver supports a given controller. If a child device is provided, 193 it further tests to see if this driver supports creating a handle for the specified child device. 194 195 This function checks to see if the driver specified by This supports the device specified by 196 ControllerHandle. Drivers will typically use the device path attached to 197 ControllerHandle and/or the services from the bus I/O abstraction attached to 198 ControllerHandle to determine if the driver supports ControllerHandle. This function 199 may be called many times during platform initialization. In order to reduce boot times, the tests 200 performed by this function must be very small, and take as little time as possible to execute. This 201 function must not change the state of any hardware devices, and this function must be aware that the 202 device specified by ControllerHandle may already be managed by the same driver or a 203 different driver. This function must match its calls to AllocatePages() with FreePages(), 204 AllocatePool() with FreePool(), and OpenProtocol() with CloseProtocol(). 205 Since ControllerHandle may have been previously started by the same driver, if a protocol is 206 already in the opened state, then it must not be closed with CloseProtocol(). This is required 207 to guarantee the state of ControllerHandle is not modified by this function. 208 209 @param[in] This A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance. 210 @param[in] ControllerHandle The handle of the controller to test. This handle 211 must support a protocol interface that supplies 212 an I/O abstraction to the driver. 213 @param[in] RemainingDevicePath A pointer to the remaining portion of a device path. This 214 parameter is ignored by device drivers, and is optional for bus 215 drivers. For bus drivers, if this parameter is not NULL, then 216 the bus driver must determine if the bus controller specified 217 by ControllerHandle and the child controller specified 218 by RemainingDevicePath are both supported by this 219 bus driver. 220 221 @retval EFI_SUCCESS The device specified by ControllerHandle and 222 RemainingDevicePath is supported by the driver specified by This. 223 @retval EFI_ALREADY_STARTED The device specified by ControllerHandle and 224 RemainingDevicePath is already being managed by the driver 225 specified by This. 226 @retval EFI_ACCESS_DENIED The device specified by ControllerHandle and 227 RemainingDevicePath is already being managed by a different 228 driver or an application that requires exclusive access. 229 Currently not implemented. 230 @retval EFI_UNSUPPORTED The device specified by ControllerHandle and 231 RemainingDevicePath is not supported by the driver specified by This. 232 **/ 233 EFI_STATUS 234 EFIAPI 235 I2cHostDriverSupported ( 236 IN EFI_DRIVER_BINDING_PROTOCOL *This, 237 IN EFI_HANDLE Controller, 238 IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath 239 ) 240 { 241 EFI_I2C_MASTER_PROTOCOL *I2cMaster; 242 EFI_I2C_BUS_CONFIGURATION_MANAGEMENT_PROTOCOL *I2cBusConfigurationManagement; 243 EFI_STATUS Status; 244 245 // 246 // Locate I2C Bus Configuration Management Protocol 247 // 248 Status = gBS->OpenProtocol ( 249 Controller, 250 &gEfiI2cBusConfigurationManagementProtocolGuid, 251 (VOID **)&I2cBusConfigurationManagement, 252 This->DriverBindingHandle, 253 Controller, 254 EFI_OPEN_PROTOCOL_BY_DRIVER 255 ); 256 if (EFI_ERROR (Status)) { 257 return Status; 258 } 259 260 // 261 // Close the protocol because we don't use it here 262 // 263 gBS->CloseProtocol ( 264 Controller, 265 &gEfiI2cBusConfigurationManagementProtocolGuid, 266 This->DriverBindingHandle, 267 Controller 268 ); 269 270 // 271 // Locate I2C Master Protocol 272 // 273 Status = gBS->OpenProtocol ( 274 Controller, 275 &gEfiI2cMasterProtocolGuid, 276 (VOID **)&I2cMaster, 277 This->DriverBindingHandle, 278 Controller, 279 EFI_OPEN_PROTOCOL_GET_PROTOCOL 280 ); 281 if (EFI_ERROR (Status)) { 282 return Status; 283 } 284 285 return EFI_SUCCESS; 286 } 287 288 /** 289 Starts a device controller or a bus controller. 290 291 The Start() function is designed to be invoked from the EFI boot service ConnectController(). 292 As a result, much of the error checking on the parameters to Start() has been moved into this 293 common boot service. It is legal to call Start() from other locations, 294 but the following calling restrictions must be followed, or the system behavior will not be deterministic. 295 1. ControllerHandle must be a valid EFI_HANDLE. 296 2. If RemainingDevicePath is not NULL, then it must be a pointer to a naturally aligned 297 EFI_DEVICE_PATH_PROTOCOL. 298 3. Prior to calling Start(), the Supported() function for the driver specified by This must 299 have been called with the same calling parameters, and Supported() must have returned EFI_SUCCESS. 300 301 @param[in] This A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance. 302 @param[in] ControllerHandle The handle of the controller to start. This handle 303 must support a protocol interface that supplies 304 an I/O abstraction to the driver. 305 @param[in] RemainingDevicePath A pointer to the remaining portion of a device path. This 306 parameter is ignored by device drivers, and is optional for bus 307 drivers. For a bus driver, if this parameter is NULL, then handles 308 for all the children of Controller are created by this driver. 309 If this parameter is not NULL and the first Device Path Node is 310 not the End of Device Path Node, then only the handle for the 311 child device specified by the first Device Path Node of 312 RemainingDevicePath is created by this driver. 313 If the first Device Path Node of RemainingDevicePath is 314 the End of Device Path Node, no child handle is created by this 315 driver. 316 317 @retval EFI_SUCCESS The device was started. 318 @retval EFI_DEVICE_ERROR The device could not be started due to a device error.Currently not implemented. 319 @retval EFI_OUT_OF_RESOURCES The request could not be completed due to a lack of resources. 320 @retval Others The driver failded to start the device. 321 322 **/ 323 EFI_STATUS 324 EFIAPI 325 I2cHostDriverStart ( 326 IN EFI_DRIVER_BINDING_PROTOCOL *This, 327 IN EFI_HANDLE Controller, 328 IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath 329 ) 330 { 331 EFI_STATUS Status; 332 EFI_I2C_MASTER_PROTOCOL *I2cMaster; 333 EFI_I2C_BUS_CONFIGURATION_MANAGEMENT_PROTOCOL *I2cBusConfigurationManagement; 334 I2C_HOST_CONTEXT *I2cHostContext; 335 336 I2cMaster = NULL; 337 I2cHostContext = NULL; 338 I2cBusConfigurationManagement = NULL; 339 340 // 341 // Locate I2C Bus Configuration Management Protocol 342 // 343 Status = gBS->OpenProtocol ( 344 Controller, 345 &gEfiI2cBusConfigurationManagementProtocolGuid, 346 (VOID **)&I2cBusConfigurationManagement, 347 This->DriverBindingHandle, 348 Controller, 349 EFI_OPEN_PROTOCOL_BY_DRIVER 350 ); 351 if (EFI_ERROR (Status)) { 352 DEBUG ((EFI_D_ERROR, "I2cHost: Open I2C bus configuration error, Status = %r\n", Status)); 353 return Status; 354 } 355 356 // 357 // Locate I2C Master Protocol 358 // 359 Status = gBS->OpenProtocol ( 360 Controller, 361 &gEfiI2cMasterProtocolGuid, 362 (VOID **)&I2cMaster, 363 This->DriverBindingHandle, 364 Controller, 365 EFI_OPEN_PROTOCOL_GET_PROTOCOL 366 ); 367 if (EFI_ERROR (Status)) { 368 DEBUG ((EFI_D_ERROR, "I2cHost: Open I2C master error, Status = %r\n", Status)); 369 goto Exit; 370 } 371 372 // 373 // Allocate the I2C Host Context structure 374 // 375 I2cHostContext = AllocateZeroPool (sizeof (I2C_HOST_CONTEXT)); 376 if (I2cHostContext == NULL) { 377 DEBUG ((EFI_D_ERROR, "I2cHost: there is no enough memory to allocate.\n")); 378 Status = EFI_OUT_OF_RESOURCES; 379 goto Exit; 380 } 381 382 // 383 // Initialize the context structure for the current I2C Controller 384 // 385 I2cHostContext->Signature = I2C_HOST_SIGNATURE; 386 I2cHostContext->I2cMaster = I2cMaster; 387 I2cHostContext->I2cBusConfigurationManagement = I2cBusConfigurationManagement; 388 I2cHostContext->I2cBusConfiguration = (UINTN) -1; 389 InitializeListHead(&I2cHostContext->RequestList); 390 391 // 392 // Reset the controller 393 // 394 Status = I2cMaster->Reset (I2cMaster); 395 if (EFI_ERROR (Status)) { 396 DEBUG ((EFI_D_ERROR, "I2cHost: I2C controller reset failed!\n")); 397 goto Exit; 398 } 399 400 // 401 // Create the I2C transaction complete event 402 // 403 Status = gBS->CreateEvent ( 404 EVT_NOTIFY_SIGNAL, 405 TPL_I2C_SYNC, 406 I2cHostRequestCompleteEvent, 407 I2cHostContext, 408 &I2cHostContext->I2cEvent 409 ); 410 if (EFI_ERROR (Status)) { 411 DEBUG ((EFI_D_ERROR, "I2cHost: create complete event error, Status = %r\n", Status)); 412 goto Exit; 413 } 414 415 // 416 // Get the bus management event 417 // 418 Status = gBS->CreateEvent ( 419 EVT_NOTIFY_SIGNAL, 420 TPL_I2C_SYNC, 421 I2cHostI2cBusConfigurationAvailable, 422 I2cHostContext, 423 &I2cHostContext->I2cBusConfigurationEvent 424 ); 425 if (EFI_ERROR (Status)) { 426 DEBUG ((EFI_D_ERROR, "I2cHost: create bus available event error, Status = %r\n", Status)); 427 goto Exit; 428 } 429 430 // 431 // Build the I2C host protocol for the current I2C controller 432 // 433 I2cHostContext->I2cHost.QueueRequest = I2cHostQueueRequest; 434 I2cHostContext->I2cHost.I2cControllerCapabilities = I2cMaster->I2cControllerCapabilities; 435 436 // 437 // Install the driver protocol 438 // 439 Status = gBS->InstallMultipleProtocolInterfaces ( 440 &Controller, 441 &gEfiI2cHostProtocolGuid, 442 &I2cHostContext->I2cHost, 443 NULL 444 ); 445 Exit: 446 if (EFI_ERROR (Status)) { 447 DEBUG ((EFI_D_ERROR, "I2cHost: Start() function failed, Status = %r\n", Status)); 448 if (I2cBusConfigurationManagement != NULL) { 449 gBS->CloseProtocol ( 450 Controller, 451 &gEfiI2cBusConfigurationManagementProtocolGuid, 452 This->DriverBindingHandle, 453 Controller 454 ); 455 } 456 457 if ((I2cHostContext != NULL) && (I2cHostContext->I2cEvent != NULL)) { 458 gBS->CloseEvent (I2cHostContext->I2cEvent); 459 I2cHostContext->I2cEvent = NULL; 460 } 461 462 if ((I2cHostContext != NULL) && (I2cHostContext->I2cBusConfigurationEvent != NULL)) { 463 gBS->CloseEvent (I2cHostContext->I2cBusConfigurationEvent); 464 I2cHostContext->I2cBusConfigurationEvent = NULL; 465 } 466 467 // 468 // Release the context structure upon failure 469 // 470 if (I2cHostContext != NULL) { 471 FreePool (I2cHostContext); 472 } 473 } 474 475 // 476 // Return the operation status. 477 // 478 return Status; 479 } 480 481 /** 482 Stops a device controller or a bus controller. 483 484 The Stop() function is designed to be invoked from the EFI boot service DisconnectController(). 485 As a result, much of the error checking on the parameters to Stop() has been moved 486 into this common boot service. It is legal to call Stop() from other locations, 487 but the following calling restrictions must be followed, or the system behavior will not be deterministic. 488 1. ControllerHandle must be a valid EFI_HANDLE that was used on a previous call to this 489 same driver's Start() function. 490 2. The first NumberOfChildren handles of ChildHandleBuffer must all be a valid 491 EFI_HANDLE. In addition, all of these handles must have been created in this driver's 492 Start() function, and the Start() function must have called OpenProtocol() on 493 ControllerHandle with an Attribute of EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER. 494 495 @param[in] This A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance. 496 @param[in] ControllerHandle A handle to the device being stopped. The handle must 497 support a bus specific I/O protocol for the driver 498 to use to stop the device. 499 @param[in] NumberOfChildren The number of child device handles in ChildHandleBuffer. 500 @param[in] ChildHandleBuffer An array of child handles to be freed. May be NULL 501 if NumberOfChildren is 0. 502 503 @retval EFI_SUCCESS The device was stopped. 504 @retval EFI_DEVICE_ERROR The device could not be stopped due to a device error. 505 506 **/ 507 EFI_STATUS 508 EFIAPI 509 I2cHostDriverStop ( 510 IN EFI_DRIVER_BINDING_PROTOCOL *This, 511 IN EFI_HANDLE Controller, 512 IN UINTN NumberOfChildren, 513 IN EFI_HANDLE *ChildHandleBuffer 514 ) 515 { 516 EFI_STATUS Status; 517 I2C_HOST_CONTEXT *I2cHostContext; 518 EFI_I2C_HOST_PROTOCOL *I2cHost; 519 EFI_TPL TplPrevious; 520 521 TplPrevious = EfiGetCurrentTpl (); 522 if (TplPrevious > TPL_I2C_SYNC) { 523 DEBUG ((EFI_D_ERROR, "I2cHost: TPL %d is too high in Stop.\n", TplPrevious)); 524 return EFI_DEVICE_ERROR; 525 } 526 527 Status = gBS->OpenProtocol ( 528 Controller, 529 &gEfiI2cHostProtocolGuid, 530 (VOID **) &I2cHost, 531 This->DriverBindingHandle, 532 Controller, 533 EFI_OPEN_PROTOCOL_GET_PROTOCOL 534 ); 535 536 if (EFI_ERROR (Status)) { 537 return EFI_DEVICE_ERROR; 538 } 539 540 I2cHostContext = I2C_HOST_CONTEXT_FROM_PROTOCOL (I2cHost); 541 542 // 543 // Raise TPL for critical section 544 // 545 TplPrevious = gBS->RaiseTPL (TPL_I2C_SYNC); 546 547 // 548 // If there is pending request or pending bus configuration, do not stop 549 // 550 Status = EFI_DEVICE_ERROR; 551 if (( !I2cHostContext->I2cBusConfigurationManagementPending ) 552 && IsListEmpty (&I2cHostContext->RequestList)) { 553 554 // 555 // Remove the I2C host protocol 556 // 557 Status = gBS->UninstallMultipleProtocolInterfaces ( 558 Controller, 559 &gEfiI2cHostProtocolGuid, 560 I2cHost, 561 NULL 562 ); 563 } 564 565 // 566 // Leave critical section 567 // 568 gBS->RestoreTPL (TplPrevious); 569 if (!EFI_ERROR (Status)) { 570 gBS->CloseProtocol ( 571 Controller, 572 &gEfiI2cBusConfigurationManagementProtocolGuid, 573 This->DriverBindingHandle, 574 Controller 575 ); 576 577 // 578 // Release I2c Host resources 579 // 580 if (I2cHostContext->I2cBusConfigurationEvent != NULL) { 581 gBS->CloseEvent (I2cHostContext->I2cBusConfigurationEvent); 582 I2cHostContext->I2cBusConfigurationEvent = NULL; 583 } 584 585 if (I2cHostContext->I2cEvent != NULL) { 586 gBS->CloseEvent (I2cHostContext->I2cEvent); 587 I2cHostContext->I2cEvent = NULL; 588 } 589 590 FreePool (I2cHostContext); 591 } 592 593 // 594 // Return the stop status 595 // 596 return Status; 597 } 598 599 /** 600 Handle the I2C bus configuration available event 601 602 This routine is called at TPL_I2C_SYNC. 603 604 @param[in] Event Address of an EFI_EVENT handle 605 @param[in] Context Address of an I2C_HOST_CONTEXT structure 606 607 **/ 608 VOID 609 EFIAPI 610 I2cHostI2cBusConfigurationAvailable ( 611 IN EFI_EVENT Event, 612 IN VOID *Context 613 ) 614 { 615 I2C_HOST_CONTEXT *I2cHostContext; 616 EFI_I2C_MASTER_PROTOCOL *I2cMaster; 617 I2C_REQUEST *I2cRequest; 618 LIST_ENTRY *EntryHeader; 619 LIST_ENTRY *Entry; 620 EFI_STATUS Status; 621 622 // 623 // Mark this I2C bus configuration management operation as complete 624 // 625 I2cHostContext = (I2C_HOST_CONTEXT *)Context; 626 I2cMaster = I2cHostContext->I2cMaster; 627 ASSERT (I2cMaster != NULL); 628 // 629 // Clear flag to indicate I2C bus configuration is finished 630 // 631 I2cHostContext->I2cBusConfigurationManagementPending = FALSE; 632 633 // 634 // Validate the completion status 635 // 636 if (EFI_ERROR (I2cHostContext->Status)) { 637 // 638 // Setting I2C bus configuration failed before 639 // 640 I2cHostRequestComplete (I2cHostContext, I2cHostContext->Status); 641 642 // 643 // Unknown I2C bus configuration 644 // Force next operation to enable the I2C bus configuration 645 // 646 I2cHostContext->I2cBusConfiguration = (UINTN) -1; 647 648 // 649 // Do not continue current I2C request 650 // 651 return; 652 } 653 654 // 655 // Get the first request in the link with FIFO order 656 // 657 EntryHeader = &I2cHostContext->RequestList; 658 Entry = GetFirstNode (EntryHeader); 659 I2cRequest = I2C_REQUEST_FROM_ENTRY (Entry); 660 661 // 662 // Update the I2C bus configuration of the current I2C request 663 // 664 I2cHostContext->I2cBusConfiguration = I2cRequest->I2cBusConfiguration; 665 666 // 667 // Start an I2C operation on the host, the status is returned by I2cHostContext->Status 668 // 669 Status = I2cMaster->StartRequest ( 670 I2cMaster, 671 I2cRequest->SlaveAddress, 672 I2cRequest->RequestPacket, 673 I2cHostContext->I2cEvent, 674 &I2cHostContext->Status 675 ); 676 677 if (EFI_ERROR (Status)) { 678 DEBUG((DEBUG_ERROR, "I2cHostI2cBusConfigurationAvailable: Error starting I2C operation, %r\n", Status)); 679 } 680 } 681 682 /** 683 Complete the current request 684 685 This routine is called at TPL_I2C_SYNC. 686 687 @param[in] I2cHostContext Address of an I2C_HOST_CONTEXT structure. 688 @param[in] Status Status of the I2C operation. 689 690 @return This routine returns the input status value. 691 692 **/ 693 EFI_STATUS 694 I2cHostRequestComplete ( 695 I2C_HOST_CONTEXT *I2cHostContext, 696 EFI_STATUS Status 697 ) 698 { 699 I2C_REQUEST *I2cRequest; 700 LIST_ENTRY *EntryHeader; 701 LIST_ENTRY *Entry; 702 703 // 704 // Remove the current I2C request from the list 705 // 706 EntryHeader = &I2cHostContext->RequestList; 707 Entry = GetFirstNode (EntryHeader); 708 I2cRequest = I2C_REQUEST_FROM_ENTRY (Entry); 709 710 // 711 // Save the status for QueueRequest 712 // 713 if ( NULL != I2cRequest->Status ) { 714 *I2cRequest->Status = Status; 715 } 716 717 // 718 // Notify the user of the I2C request completion 719 // 720 if ( NULL != I2cRequest->Event ) { 721 gBS->SignalEvent (I2cRequest->Event); 722 } 723 724 // 725 // Done with this request, remove the current request from list 726 // 727 RemoveEntryList (&I2cRequest->Link); 728 FreePool (I2cRequest->RequestPacket); 729 FreePool (I2cRequest); 730 731 // 732 // If there is more I2C request, start next one 733 // 734 if(!IsListEmpty (EntryHeader)) { 735 I2cHostRequestEnable (I2cHostContext); 736 } 737 738 return Status; 739 } 740 741 /** 742 Handle the bus available event 743 744 This routine is called at TPL_I2C_SYNC. 745 746 @param[in] Event Address of an EFI_EVENT handle 747 @param[in] Context Address of an I2C_HOST_CONTEXT structure 748 749 **/ 750 VOID 751 EFIAPI 752 I2cHostRequestCompleteEvent ( 753 IN EFI_EVENT Event, 754 IN VOID *Context 755 ) 756 { 757 I2C_HOST_CONTEXT *I2cHostContext; 758 759 // 760 // Handle the completion event 761 // 762 I2cHostContext = (I2C_HOST_CONTEXT *)Context; 763 I2cHostRequestComplete (I2cHostContext, I2cHostContext->Status); 764 } 765 766 /** 767 Enable access to the I2C bus configuration 768 769 @param[in] I2cHostContext Address of an I2C_HOST_CONTEXT structure 770 771 @retval EFI_SUCCESS The operation completed successfully. 772 @retval EFI_ABORTED The request did not complete because the driver 773 was shutdown. 774 @retval EFI_BAD_BUFFER_SIZE The WriteBytes or ReadBytes buffer size is too large. 775 @retval EFI_DEVICE_ERROR There was an I2C error (NACK) during the operation. 776 This could indicate the slave device is not present. 777 @retval EFI_INVALID_PARAMETER RequestPacket is NULL 778 @retval EFI_NO_MAPPING Invalid I2cBusConfiguration value 779 @retval EFI_NO_RESPONSE The I2C device is not responding to the 780 slave address. EFI_DEVICE_ERROR may also be 781 returned if the controller can not distinguish 782 when the NACK occurred. 783 @retval EFI_NOT_FOUND I2C slave address exceeds maximum address 784 @retval EFI_NOT_READY I2C bus is busy or operation pending, wait for 785 the event and then read status. 786 @retval EFI_OUT_OF_RESOURCES Insufficient memory for I2C operation 787 @retval EFI_TIMEOUT The transaction did not complete within an internally 788 specified timeout period. 789 790 **/ 791 EFI_STATUS 792 I2cHostRequestEnable ( 793 I2C_HOST_CONTEXT *I2cHostContext 794 ) 795 { 796 UINTN I2cBusConfiguration; 797 CONST EFI_I2C_BUS_CONFIGURATION_MANAGEMENT_PROTOCOL *I2cBusConfigurationManagement; 798 I2C_REQUEST *I2cRequest; 799 EFI_STATUS Status; 800 EFI_TPL TplPrevious; 801 LIST_ENTRY *EntryHeader; 802 LIST_ENTRY *Entry; 803 804 // 805 // Assume pending request 806 // 807 Status = EFI_NOT_READY; 808 809 I2cBusConfigurationManagement = I2cHostContext->I2cBusConfigurationManagement; 810 811 // 812 // Validate the I2c bus configuration 813 // 814 EntryHeader = &I2cHostContext->RequestList; 815 Entry = GetFirstNode (EntryHeader); 816 I2cRequest = I2C_REQUEST_FROM_ENTRY (Entry); 817 818 I2cBusConfiguration = I2cRequest->I2cBusConfiguration; 819 820 if (I2cHostContext->I2cBusConfiguration != I2cBusConfiguration ) { 821 // 822 // Set flag to indicate I2C bus configuration is in progress 823 // 824 I2cHostContext->I2cBusConfigurationManagementPending = TRUE; 825 // 826 // Update bus configuration for this device's requesting bus configuration 827 // 828 Status = I2cBusConfigurationManagement->EnableI2cBusConfiguration ( 829 I2cBusConfigurationManagement, 830 I2cBusConfiguration, 831 I2cHostContext->I2cBusConfigurationEvent, 832 &I2cHostContext->Status 833 ); 834 } else { 835 // 836 // I2C bus configuration is same, no need change configuration and start I2c transaction directly 837 // 838 TplPrevious = gBS->RaiseTPL ( TPL_I2C_SYNC ); 839 840 // 841 // Same I2C bus configuration 842 // 843 I2cHostContext->Status = EFI_SUCCESS; 844 I2cHostI2cBusConfigurationAvailable (I2cHostContext->I2cBusConfigurationEvent, I2cHostContext); 845 846 // 847 // Release the thread synchronization 848 // 849 gBS->RestoreTPL ( TplPrevious ); 850 } 851 return Status; 852 } 853 854 /** 855 Queue an I2C operation for execution on the I2C controller. 856 857 This routine must be called at or below TPL_NOTIFY. For synchronous 858 requests this routine must be called at or below TPL_CALLBACK. 859 860 N.B. The typical consumers of this API are the I2C bus driver and 861 on rare occasions the I2C test application. Extreme care must be 862 taken by other consumers of this API to prevent confusing the 863 third party I2C drivers due to a state change at the I2C device 864 which the third party I2C drivers did not initiate. I2C platform 865 drivers may use this API within these guidelines. 866 867 This layer uses the concept of I2C bus configurations to describe 868 the I2C bus. An I2C bus configuration is defined as a unique 869 setting of the multiplexers and switches in the I2C bus which 870 enable access to one or more I2C devices. When using a switch 871 to divide a bus, due to speed differences, the I2C platform layer 872 would define an I2C bus configuration for the I2C devices on each 873 side of the switch. When using a multiplexer, the I2C platform 874 layer defines an I2C bus configuration for each of the selector 875 values required to control the multiplexer. See Figure 1 in the 876 <a href="http://www.nxp.com/documents/user_manual/UM10204.pdf">I<sup>2</sup>C 877 Specification</a> for a complex I2C bus configuration. 878 879 The I2C host driver processes all operations in FIFO order. Prior to 880 performing the operation, the I2C host driver calls the I2C platform 881 driver to reconfigure the switches and multiplexers in the I2C bus 882 enabling access to the specified I2C device. The I2C platform driver 883 also selects the maximum bus speed for the device. After the I2C bus 884 is configured, the I2C host driver calls the I2C port driver to 885 initialize the I2C controller and start the I2C operation. 886 887 @param[in] This Address of an EFI_I2C_HOST_PROTOCOL instance. 888 @param[in] I2cBusConfiguration I2C bus configuration to access the I2C 889 device. 890 @param[in] SlaveAddress Address of the device on the I2C bus. 891 @param[in] Event Event to set for asynchronous operations, 892 NULL for synchronous operations 893 @param[in] RequestPacket Address of an EFI_I2C_REQUEST_PACKET 894 structure describing the I2C operation 895 @param[out] I2cStatus Optional buffer to receive the I2C operation 896 completion status 897 898 @retval EFI_SUCCESS The operation completed successfully. 899 @retval EFI_BAD_BUFFER_SIZE The WriteBytes or ReadBytes buffer size is too large. 900 @retval EFI_DEVICE_ERROR There was an I2C error (NACK) during the operation. 901 This could indicate the slave device is not present. 902 @retval EFI_INVALID_PARAMETER RequestPacket is NULL 903 @retval EFI_INVALID_PARAMETER TPL is too high 904 @retval EFI_NO_MAPPING Invalid I2cBusConfiguration value 905 @retval EFI_NO_RESPONSE The I2C device is not responding to the 906 slave address. EFI_DEVICE_ERROR may also be 907 returned if the controller can not distinguish 908 when the NACK occurred. 909 @retval EFI_NOT_FOUND I2C slave address exceeds maximum address 910 @retval EFI_NOT_READY I2C bus is busy or operation pending, wait for 911 the event and then read status pointed to by 912 the request packet. 913 @retval EFI_OUT_OF_RESOURCES Insufficient memory for I2C operation 914 @retval EFI_TIMEOUT The transaction did not complete within an internally 915 specified timeout period. 916 917 **/ 918 EFI_STATUS 919 EFIAPI 920 I2cHostQueueRequest ( 921 IN CONST EFI_I2C_HOST_PROTOCOL *This, 922 IN UINTN I2cBusConfiguration, 923 IN UINTN SlaveAddress, 924 IN EFI_EVENT Event OPTIONAL, 925 IN EFI_I2C_REQUEST_PACKET *RequestPacket, 926 OUT EFI_STATUS *I2cStatus OPTIONAL 927 ) 928 { 929 EFI_STATUS Status; 930 EFI_EVENT SyncEvent; 931 EFI_TPL TplPrevious; 932 I2C_REQUEST *I2cRequest; 933 I2C_HOST_CONTEXT *I2cHostContext; 934 BOOLEAN FirstRequest; 935 UINTN RequestPacketSize; 936 UINTN StartBit; 937 938 SyncEvent = NULL; 939 FirstRequest = FALSE; 940 Status = EFI_SUCCESS; 941 942 if (RequestPacket == NULL) { 943 return EFI_INVALID_PARAMETER; 944 } 945 946 if ((SlaveAddress & I2C_ADDRESSING_10_BIT) != 0) { 947 // 948 // 10-bit address, bits 0-9 are used for 10-bit I2C slave addresses, 949 // bits 10-30 are reserved bits and must be zero 950 // 951 StartBit = 10; 952 } else { 953 // 954 // 7-bit address, Bits 0-6 are used for 7-bit I2C slave addresses, 955 // bits 7-30 are reserved bits and must be zero 956 // 957 StartBit = 7; 958 } 959 960 if (BitFieldRead32 ((UINT32)SlaveAddress, StartBit, 30) != 0) { 961 // 962 // Reserved bit set in the SlaveAddress parameter 963 // 964 return EFI_NOT_FOUND; 965 } 966 967 I2cHostContext = I2C_HOST_CONTEXT_FROM_PROTOCOL (This); 968 969 if (Event == NULL) { 970 // 971 // For synchronous transaction, register an event used to wait for finishing synchronous transaction 972 // 973 Status = gBS->CreateEvent ( 974 0, 975 TPL_I2C_SYNC, 976 NULL, 977 NULL, 978 &SyncEvent 979 ); 980 if (EFI_ERROR (Status)) { 981 return Status; 982 } 983 } 984 985 // 986 // TPL should be at or below TPL_NOTIFY. 987 // For synchronous requests this routine must be called at or below TPL_CALLBACK. 988 // 989 TplPrevious = EfiGetCurrentTpl (); 990 if ((TplPrevious > TPL_I2C_SYNC) || ((Event == NULL) && (TplPrevious > TPL_CALLBACK))) { 991 DEBUG ((EFI_D_ERROR, "ERROR - TPL %d is too high!\n", TplPrevious)); 992 return EFI_INVALID_PARAMETER; 993 } 994 995 // 996 // Allocate the request structure 997 // 998 I2cRequest = AllocateZeroPool (sizeof (I2C_REQUEST)); 999 if (I2cRequest == NULL) { 1000 DEBUG ((EFI_D_ERROR, "WARNING - Failed to allocate I2C_REQUEST!\n")); 1001 return EFI_OUT_OF_RESOURCES; 1002 } 1003 1004 // 1005 // Initialize the request 1006 // 1007 I2cRequest->Signature = I2C_REQUEST_SIGNATURE; 1008 I2cRequest->I2cBusConfiguration = I2cBusConfiguration; 1009 I2cRequest->SlaveAddress = SlaveAddress; 1010 I2cRequest->Event = (Event == NULL) ? SyncEvent : Event; 1011 I2cRequest->Status = I2cStatus; 1012 1013 // 1014 // Copy request packet into private buffer, as RequestPacket may be freed during asynchronous transaction 1015 // 1016 RequestPacketSize = sizeof (UINTN) + RequestPacket->OperationCount * sizeof (EFI_I2C_OPERATION); 1017 I2cRequest->RequestPacket = AllocateZeroPool (RequestPacketSize); 1018 ASSERT (I2cRequest->RequestPacket != NULL); 1019 CopyMem (I2cRequest->RequestPacket, RequestPacket, RequestPacketSize); 1020 1021 // 1022 // Synchronize with the other threads 1023 // 1024 gBS->RaiseTPL ( TPL_I2C_SYNC ); 1025 1026 FirstRequest = IsListEmpty (&I2cHostContext->RequestList); 1027 1028 // 1029 // Insert new I2C request in the list 1030 // 1031 InsertTailList (&I2cHostContext->RequestList, &I2cRequest->Link); 1032 1033 // 1034 // Release the thread synchronization 1035 // 1036 gBS->RestoreTPL (TplPrevious); 1037 1038 if (FirstRequest) { 1039 // 1040 // Start the first I2C request, then the subsequent of I2C request will continue 1041 // 1042 Status = I2cHostRequestEnable (I2cHostContext); 1043 } 1044 1045 if (Event != NULL) { 1046 // 1047 // For asynchronous, return EFI_SUCCESS indicating that the asynchronously I2C transaction was queued. 1048 // No real I2C operation status in I2cStatus 1049 // 1050 return EFI_SUCCESS; 1051 } 1052 1053 // 1054 // For synchronous transaction, wait for the operation completion 1055 // 1056 do { 1057 Status = gBS->CheckEvent (SyncEvent); 1058 } while (Status == EFI_NOT_READY); 1059 1060 // 1061 // Get the I2C operation status 1062 // 1063 Status = I2cHostContext->Status; 1064 1065 // 1066 // Return the I2C operation status 1067 // 1068 if (I2cStatus != NULL) { 1069 *I2cStatus = Status; 1070 } 1071 1072 // 1073 // Close the event if necessary 1074 // 1075 if (SyncEvent != NULL) { 1076 gBS->CloseEvent (SyncEvent); 1077 } 1078 1079 return Status; 1080 } 1081 1082 /** 1083 The user Entry Point for I2C host module. The user code starts with this function. 1084 1085 @param[in] ImageHandle The firmware allocated handle for the EFI image. 1086 @param[in] SystemTable A pointer to the EFI System Table. 1087 1088 @retval EFI_SUCCESS The entry point is executed successfully. 1089 @retval other Some error occurs when executing this entry point. 1090 1091 **/ 1092 EFI_STATUS 1093 EFIAPI 1094 InitializeI2cHost( 1095 IN EFI_HANDLE ImageHandle, 1096 IN EFI_SYSTEM_TABLE *SystemTable 1097 ) 1098 { 1099 EFI_STATUS Status; 1100 1101 // 1102 // Install driver model protocol(s). 1103 // 1104 Status = EfiLibInstallDriverBindingComponentName2 ( 1105 ImageHandle, 1106 SystemTable, 1107 &gI2cHostDriverBinding, 1108 ImageHandle, 1109 &gI2cHostComponentName, 1110 &gI2cHostComponentName2 1111 ); 1112 ASSERT_EFI_ERROR (Status); 1113 return Status; 1114 } 1115 1116 /** 1117 This is the unload handle for I2C host module. 1118 1119 Disconnect the driver specified by ImageHandle from all the devices in the handle database. 1120 Uninstall all the protocols installed in the driver entry point. 1121 1122 @param[in] ImageHandle The drivers' driver image. 1123 1124 @retval EFI_SUCCESS The image is unloaded. 1125 @retval Others Failed to unload the image. 1126 1127 **/ 1128 EFI_STATUS 1129 EFIAPI 1130 I2cHostUnload ( 1131 IN EFI_HANDLE ImageHandle 1132 ) 1133 { 1134 EFI_STATUS Status; 1135 EFI_HANDLE *DeviceHandleBuffer; 1136 UINTN DeviceHandleCount; 1137 UINTN Index; 1138 EFI_COMPONENT_NAME_PROTOCOL *ComponentName; 1139 EFI_COMPONENT_NAME2_PROTOCOL *ComponentName2; 1140 1141 // 1142 // Get the list of all I2C Controller handles in the handle database. 1143 // If there is an error getting the list, then the unload 1144 // operation fails. 1145 // 1146 Status = gBS->LocateHandleBuffer ( 1147 ByProtocol, 1148 &gEfiI2cHostProtocolGuid, 1149 NULL, 1150 &DeviceHandleCount, 1151 &DeviceHandleBuffer 1152 ); 1153 1154 if (!EFI_ERROR (Status)) { 1155 // 1156 // Disconnect the driver specified by ImageHandle from all 1157 // the devices in the handle database. 1158 // 1159 for (Index = 0; Index < DeviceHandleCount; Index++) { 1160 Status = gBS->DisconnectController ( 1161 DeviceHandleBuffer[Index], 1162 ImageHandle, 1163 NULL 1164 ); 1165 if (EFI_ERROR (Status)) { 1166 goto Done; 1167 } 1168 } 1169 } 1170 1171 // 1172 // Uninstall all the protocols installed in the driver entry point 1173 // 1174 Status = gBS->UninstallMultipleProtocolInterfaces ( 1175 gI2cHostDriverBinding.DriverBindingHandle, 1176 &gEfiDriverBindingProtocolGuid, 1177 &gI2cHostDriverBinding, 1178 NULL 1179 ); 1180 ASSERT_EFI_ERROR (Status); 1181 1182 // 1183 // Note we have to one by one uninstall the following protocols. 1184 // It's because some of them are optionally installed based on 1185 // the following PCD settings. 1186 // gEfiMdePkgTokenSpaceGuid.PcdDriverDiagnosticsDisable 1187 // gEfiMdePkgTokenSpaceGuid.PcdComponentNameDisable 1188 // gEfiMdePkgTokenSpaceGuid.PcdDriverDiagnostics2Disable 1189 // gEfiMdePkgTokenSpaceGuid.PcdComponentName2Disable 1190 // 1191 Status = gBS->HandleProtocol ( 1192 gI2cHostDriverBinding.DriverBindingHandle, 1193 &gEfiComponentNameProtocolGuid, 1194 (VOID **) &ComponentName 1195 ); 1196 if (!EFI_ERROR (Status)) { 1197 gBS->UninstallProtocolInterface ( 1198 gI2cHostDriverBinding.DriverBindingHandle, 1199 &gEfiComponentNameProtocolGuid, 1200 ComponentName 1201 ); 1202 } 1203 1204 Status = gBS->HandleProtocol ( 1205 gI2cHostDriverBinding.DriverBindingHandle, 1206 &gEfiComponentName2ProtocolGuid, 1207 (VOID **) &ComponentName2 1208 ); 1209 if (!EFI_ERROR (Status)) { 1210 gBS->UninstallProtocolInterface ( 1211 gI2cHostDriverBinding.DriverBindingHandle, 1212 &gEfiComponentName2ProtocolGuid, 1213 ComponentName2 1214 ); 1215 } 1216 1217 Status = EFI_SUCCESS; 1218 1219 Done: 1220 // 1221 // Free the buffer containing the list of handles from the handle database 1222 // 1223 if (DeviceHandleBuffer != NULL) { 1224 gBS->FreePool (DeviceHandleBuffer); 1225 } 1226 1227 return Status; 1228 } 1229
