319507cfa2cefde9628c13b1640b488c847597a0
[mirror_edk2.git] / MdeModulePkg / Bus / I2c / I2cDxe / I2cHost.c
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 - 2014, 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_ABORTED The request did not complete because the driver
900 was shutdown.
901 @retval EFI_BAD_BUFFER_SIZE The WriteBytes or ReadBytes buffer size is too large.
902 @retval EFI_DEVICE_ERROR There was an I2C error (NACK) during the operation.
903 This could indicate the slave device is not present.
904 @retval EFI_INVALID_PARAMETER RequestPacket is NULL
905 @retval EFI_INVALID_PARAMETER TPL is too high
906 @retval EFI_NO_MAPPING Invalid I2cBusConfiguration value
907 @retval EFI_NO_RESPONSE The I2C device is not responding to the
908 slave address. EFI_DEVICE_ERROR may also be
909 returned if the controller can not distinguish
910 when the NACK occurred.
911 @retval EFI_NOT_FOUND I2C slave address exceeds maximum address
912 @retval EFI_NOT_READY I2C bus is busy or operation pending, wait for
913 the event and then read status pointed to by
914 the request packet.
915 @retval EFI_OUT_OF_RESOURCES Insufficient memory for I2C operation
916 @retval EFI_TIMEOUT The transaction did not complete within an internally
917 specified timeout period.
918
919 **/
920 EFI_STATUS
921 EFIAPI
922 I2cHostQueueRequest (
923 IN CONST EFI_I2C_HOST_PROTOCOL *This,
924 IN UINTN I2cBusConfiguration,
925 IN UINTN SlaveAddress,
926 IN EFI_EVENT Event OPTIONAL,
927 IN EFI_I2C_REQUEST_PACKET *RequestPacket,
928 OUT EFI_STATUS *I2cStatus OPTIONAL
929 )
930 {
931 EFI_STATUS Status;
932 EFI_EVENT SyncEvent;
933 EFI_TPL TplPrevious;
934 I2C_REQUEST *I2cRequest;
935 I2C_HOST_CONTEXT *I2cHostContext;
936 BOOLEAN FirstRequest;
937 UINTN RequestPacketSize;
938 UINTN StartBit;
939
940 SyncEvent = NULL;
941 FirstRequest = FALSE;
942 Status = EFI_SUCCESS;
943
944 if (RequestPacket == NULL) {
945 return EFI_INVALID_PARAMETER;
946 }
947
948 if ((SlaveAddress & I2C_ADDRESSING_10_BIT) != 0) {
949 //
950 // 10-bit address, bits 0-9 are used for 10-bit I2C slave addresses,
951 // bits 10-30 are reserved bits and must be zero
952 //
953 StartBit = 10;
954 } else {
955 //
956 // 7-bit address, Bits 0-6 are used for 7-bit I2C slave addresses,
957 // bits 7-30 are reserved bits and must be zero
958 //
959 StartBit = 7;
960 }
961
962 if (BitFieldRead32 ((UINT32)SlaveAddress, StartBit, 30) != 0) {
963 //
964 // Reserved bit set in the SlaveAddress parameter
965 //
966 return EFI_NOT_FOUND;
967 }
968
969 I2cHostContext = I2C_HOST_CONTEXT_FROM_PROTOCOL (This);
970
971 if (Event == NULL) {
972 //
973 // For synchronous transaction, register an event used to wait for finishing synchronous transaction
974 //
975 Status = gBS->CreateEvent (
976 0,
977 TPL_I2C_SYNC,
978 NULL,
979 NULL,
980 &SyncEvent
981 );
982 if (EFI_ERROR (Status)) {
983 return Status;
984 }
985 }
986
987 //
988 // TPL should be at or below TPL_NOTIFY.
989 // For synchronous requests this routine must be called at or below TPL_CALLBACK.
990 //
991 TplPrevious = EfiGetCurrentTpl ();
992 if ((TplPrevious > TPL_I2C_SYNC) || ((Event == NULL) && (TplPrevious > TPL_CALLBACK))) {
993 DEBUG ((EFI_D_ERROR, "ERROR - TPL %d is too high!\n", TplPrevious));
994 return EFI_INVALID_PARAMETER;
995 }
996
997 //
998 // Allocate the request structure
999 //
1000 I2cRequest = AllocateZeroPool (sizeof (I2C_REQUEST));
1001 if (I2cRequest == NULL) {
1002 DEBUG ((EFI_D_ERROR, "WARNING - Failed to allocate I2C_REQUEST!\n"));
1003 return EFI_OUT_OF_RESOURCES;
1004 }
1005
1006 //
1007 // Initialize the request
1008 //
1009 I2cRequest->Signature = I2C_REQUEST_SIGNATURE;
1010 I2cRequest->I2cBusConfiguration = I2cBusConfiguration;
1011 I2cRequest->SlaveAddress = SlaveAddress;
1012 I2cRequest->Event = (Event == NULL) ? SyncEvent : Event;
1013 I2cRequest->Status = I2cStatus;
1014
1015 //
1016 // Copy request packet into private buffer, as RequestPacket may be freed during asynchronous transaction
1017 //
1018 RequestPacketSize = sizeof (UINTN) + RequestPacket->OperationCount * sizeof (EFI_I2C_OPERATION);
1019 I2cRequest->RequestPacket = AllocateZeroPool (RequestPacketSize);
1020 ASSERT (I2cRequest->RequestPacket != NULL);
1021 CopyMem (I2cRequest->RequestPacket, RequestPacket, RequestPacketSize);
1022
1023 //
1024 // Synchronize with the other threads
1025 //
1026 gBS->RaiseTPL ( TPL_I2C_SYNC );
1027
1028 FirstRequest = IsListEmpty (&I2cHostContext->RequestList);
1029
1030 //
1031 // Insert new I2C request in the list
1032 //
1033 InsertTailList (&I2cHostContext->RequestList, &I2cRequest->Link);
1034
1035 //
1036 // Release the thread synchronization
1037 //
1038 gBS->RestoreTPL (TplPrevious);
1039
1040 if (FirstRequest) {
1041 //
1042 // Start the first I2C request, then the subsequent of I2C request will continue
1043 //
1044 Status = I2cHostRequestEnable (I2cHostContext);
1045 }
1046
1047 if (Event != NULL) {
1048 //
1049 // For asynchronous, return EFI_SUCCESS indicating that the asynchronously I2C transaction was queued.
1050 // No real I2C operation status in I2cStatus
1051 //
1052 return EFI_SUCCESS;
1053 }
1054
1055 //
1056 // For synchronous transaction, wait for the operation completion
1057 //
1058 do {
1059 Status = gBS->CheckEvent (SyncEvent);
1060 } while (Status == EFI_NOT_READY);
1061
1062 //
1063 // Get the I2C operation status
1064 //
1065 Status = I2cHostContext->Status;
1066
1067 //
1068 // Return the I2C operation status
1069 //
1070 if (I2cStatus != NULL) {
1071 *I2cStatus = Status;
1072 }
1073
1074 //
1075 // Close the event if necessary
1076 //
1077 if (SyncEvent != NULL) {
1078 gBS->CloseEvent (SyncEvent);
1079 }
1080
1081 return Status;
1082 }
1083
1084 /**
1085 The user Entry Point for I2C host module. The user code starts with this function.
1086
1087 @param[in] ImageHandle The firmware allocated handle for the EFI image.
1088 @param[in] SystemTable A pointer to the EFI System Table.
1089
1090 @retval EFI_SUCCESS The entry point is executed successfully.
1091 @retval other Some error occurs when executing this entry point.
1092
1093 **/
1094 EFI_STATUS
1095 EFIAPI
1096 InitializeI2cHost(
1097 IN EFI_HANDLE ImageHandle,
1098 IN EFI_SYSTEM_TABLE *SystemTable
1099 )
1100 {
1101 EFI_STATUS Status;
1102
1103 //
1104 // Install driver model protocol(s).
1105 //
1106 Status = EfiLibInstallDriverBindingComponentName2 (
1107 ImageHandle,
1108 SystemTable,
1109 &gI2cHostDriverBinding,
1110 ImageHandle,
1111 &gI2cHostComponentName,
1112 &gI2cHostComponentName2
1113 );
1114 ASSERT_EFI_ERROR (Status);
1115 return Status;
1116 }
1117
1118 /**
1119 This is the unload handle for I2C host module.
1120
1121 Disconnect the driver specified by ImageHandle from all the devices in the handle database.
1122 Uninstall all the protocols installed in the driver entry point.
1123
1124 @param[in] ImageHandle The drivers' driver image.
1125
1126 @retval EFI_SUCCESS The image is unloaded.
1127 @retval Others Failed to unload the image.
1128
1129 **/
1130 EFI_STATUS
1131 EFIAPI
1132 I2cHostUnload (
1133 IN EFI_HANDLE ImageHandle
1134 )
1135 {
1136 EFI_STATUS Status;
1137 EFI_HANDLE *DeviceHandleBuffer;
1138 UINTN DeviceHandleCount;
1139 UINTN Index;
1140 EFI_COMPONENT_NAME_PROTOCOL *ComponentName;
1141 EFI_COMPONENT_NAME2_PROTOCOL *ComponentName2;
1142
1143 //
1144 // Get the list of all I2C Controller handles in the handle database.
1145 // If there is an error getting the list, then the unload
1146 // operation fails.
1147 //
1148 Status = gBS->LocateHandleBuffer (
1149 ByProtocol,
1150 &gEfiI2cHostProtocolGuid,
1151 NULL,
1152 &DeviceHandleCount,
1153 &DeviceHandleBuffer
1154 );
1155
1156 if (!EFI_ERROR (Status)) {
1157 //
1158 // Disconnect the driver specified by ImageHandle from all
1159 // the devices in the handle database.
1160 //
1161 for (Index = 0; Index < DeviceHandleCount; Index++) {
1162 Status = gBS->DisconnectController (
1163 DeviceHandleBuffer[Index],
1164 ImageHandle,
1165 NULL
1166 );
1167 if (EFI_ERROR (Status)) {
1168 goto Done;
1169 }
1170 }
1171 }
1172
1173 //
1174 // Uninstall all the protocols installed in the driver entry point
1175 //
1176 Status = gBS->UninstallMultipleProtocolInterfaces (
1177 gI2cHostDriverBinding.DriverBindingHandle,
1178 &gEfiDriverBindingProtocolGuid,
1179 &gI2cHostDriverBinding,
1180 NULL
1181 );
1182 ASSERT_EFI_ERROR (Status);
1183
1184 //
1185 // Note we have to one by one uninstall the following protocols.
1186 // It's because some of them are optionally installed based on
1187 // the following PCD settings.
1188 // gEfiMdePkgTokenSpaceGuid.PcdDriverDiagnosticsDisable
1189 // gEfiMdePkgTokenSpaceGuid.PcdComponentNameDisable
1190 // gEfiMdePkgTokenSpaceGuid.PcdDriverDiagnostics2Disable
1191 // gEfiMdePkgTokenSpaceGuid.PcdComponentName2Disable
1192 //
1193 Status = gBS->HandleProtocol (
1194 gI2cHostDriverBinding.DriverBindingHandle,
1195 &gEfiComponentNameProtocolGuid,
1196 (VOID **) &ComponentName
1197 );
1198 if (!EFI_ERROR (Status)) {
1199 gBS->UninstallProtocolInterface (
1200 gI2cHostDriverBinding.DriverBindingHandle,
1201 &gEfiComponentNameProtocolGuid,
1202 ComponentName
1203 );
1204 }
1205
1206 Status = gBS->HandleProtocol (
1207 gI2cHostDriverBinding.DriverBindingHandle,
1208 &gEfiComponentName2ProtocolGuid,
1209 (VOID **) &ComponentName2
1210 );
1211 if (!EFI_ERROR (Status)) {
1212 gBS->UninstallProtocolInterface (
1213 gI2cHostDriverBinding.DriverBindingHandle,
1214 &gEfiComponentName2ProtocolGuid,
1215 ComponentName2
1216 );
1217 }
1218
1219 Status = EFI_SUCCESS;
1220
1221 Done:
1222 //
1223 // Free the buffer containing the list of handles from the handle database
1224 //
1225 if (DeviceHandleBuffer != NULL) {
1226 gBS->FreePool (DeviceHandleBuffer);
1227 }
1228
1229 return Status;
1230 }