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|
/** @file
Private data structures for the I2C DXE driver.
This file defines common data structures, macro definitions and some module
internal function header files.
Copyright (c) 2013 - 2018, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#ifndef __I2C_DXE_H__
#define __I2C_DXE_H__
#include <Uefi.h>
#include <Library/BaseMemoryLib.h>
#include <Library/DebugLib.h>
#include <Library/DevicePathLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/TimerLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/UefiDriverEntryPoint.h>
#include <Library/UefiLib.h>
#include <Protocol/DriverBinding.h>
#include <Protocol/I2cEnumerate.h>
#include <Protocol/I2cHost.h>
#include <Protocol/I2cIo.h>
#include <Protocol/I2cMaster.h>
#include <Protocol/I2cBusConfigurationManagement.h>
#include <Protocol/LoadedImage.h>
#define I2C_DEVICE_SIGNATURE SIGNATURE_32 ('I', '2', 'C', 'D')
#define I2C_HOST_SIGNATURE SIGNATURE_32 ('I', '2', 'C', 'H')
#define I2C_REQUEST_SIGNATURE SIGNATURE_32 ('I', '2', 'C', 'R')
//
// Synchronize access to the list of requests
//
#define TPL_I2C_SYNC TPL_NOTIFY
//
// I2C bus context
//
typedef struct {
EFI_I2C_ENUMERATE_PROTOCOL *I2cEnumerate;
EFI_I2C_HOST_PROTOCOL *I2cHost;
EFI_HANDLE Controller;
EFI_DEVICE_PATH_PROTOCOL *ParentDevicePath;
EFI_HANDLE DriverBindingHandle;
} I2C_BUS_CONTEXT;
//
// I2C device context
//
typedef struct {
//
// Structure identification
//
UINT32 Signature;
//
// I2c device handle
//
EFI_HANDLE Handle;
//
// Upper level API to support the I2C device I/O
//
EFI_I2C_IO_PROTOCOL I2cIo;
//
// Device path for this device
//
EFI_DEVICE_PATH_PROTOCOL *DevicePath;
//
// Platform specific data for this device
//
CONST EFI_I2C_DEVICE *I2cDevice;
//
// Context for the common I/O support including the
// lower level API to the host controller.
//
I2C_BUS_CONTEXT *I2cBusContext;
} I2C_DEVICE_CONTEXT;
#define I2C_DEVICE_CONTEXT_FROM_PROTOCOL(a) CR (a, I2C_DEVICE_CONTEXT, I2cIo, I2C_DEVICE_SIGNATURE)
//
// I2C Request
//
typedef struct {
//
// Signature
//
UINT32 Signature;
//
// Next request in the pending request list
//
LIST_ENTRY Link;
//
// I2C bus configuration for the operation
//
UINTN I2cBusConfiguration;
//
// I2C slave address for the operation
//
UINTN SlaveAddress;
//
// Event to set for asynchronous operations, NULL for
// synchronous operations
//
EFI_EVENT Event;
//
// I2C operation description
//
EFI_I2C_REQUEST_PACKET *RequestPacket;
//
// Optional buffer to receive the I2C operation completion status
//
EFI_STATUS *Status;
} I2C_REQUEST;
#define I2C_REQUEST_FROM_ENTRY(a) CR (a, I2C_REQUEST, Link, I2C_REQUEST_SIGNATURE);
//
// I2C host context
//
typedef struct {
//
// Structure identification
//
UINTN Signature;
//
// Current I2C bus configuration
//
UINTN I2cBusConfiguration;
//
// I2C bus configuration management event
//
EFI_EVENT I2cBusConfigurationEvent;
//
// I2C operation completion event
//
EFI_EVENT I2cEvent;
//
// I2C operation and I2C bus configuration management status
//
EFI_STATUS Status;
//
// I2C bus configuration management operation pending
//
BOOLEAN I2cBusConfigurationManagementPending;
//
// I2C request list maintained by I2C Host
//
LIST_ENTRY RequestList;
//
// Upper level API
//
EFI_I2C_HOST_PROTOCOL I2cHost;
//
// I2C bus configuration management protocol
//
EFI_I2C_BUS_CONFIGURATION_MANAGEMENT_PROTOCOL *I2cBusConfigurationManagement;
//
// Lower level API for I2C master (controller)
//
EFI_I2C_MASTER_PROTOCOL *I2cMaster;
} I2C_HOST_CONTEXT;
#define I2C_HOST_CONTEXT_FROM_PROTOCOL(a) CR (a, I2C_HOST_CONTEXT, I2cHost, I2C_HOST_SIGNATURE)
//
// Global Variables
//
extern EFI_COMPONENT_NAME_PROTOCOL gI2cBusComponentName;
extern EFI_COMPONENT_NAME2_PROTOCOL gI2cBusComponentName2;
extern EFI_DRIVER_BINDING_PROTOCOL gI2cBusDriverBinding;
extern EFI_COMPONENT_NAME_PROTOCOL gI2cHostComponentName;
extern EFI_COMPONENT_NAME2_PROTOCOL gI2cHostComponentName2;
extern EFI_DRIVER_BINDING_PROTOCOL gI2cHostDriverBinding;
/**
Start the I2C driver
This routine allocates the necessary resources for the driver.
This routine is called by I2cBusDriverStart to complete the driver
initialization.
@param[in] I2cBus Address of an I2C_BUS_CONTEXT structure
@param[in] Controller Handle to the controller
@param[in] RemainingDevicePath A pointer to the remaining portion of a device path.
@retval EFI_SUCCESS Driver API properly initialized
**/
EFI_STATUS
RegisterI2cDevice (
IN I2C_BUS_CONTEXT *I2cBus,
IN EFI_HANDLE Controller,
IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath
);
/**
Unregister an I2C device.
This function removes the protocols installed on the controller handle and
frees the resources allocated for the I2C device.
@param This The pointer to EFI_DRIVER_BINDING_PROTOCOL instance.
@param Controller The controller handle of the I2C device.
@param Handle The child handle.
@retval EFI_SUCCESS The I2C device is successfully unregistered.
@return Others Some error occurs when unregistering the I2C device.
**/
EFI_STATUS
UnRegisterI2cDevice (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE Controller,
IN EFI_HANDLE Handle
);
/**
Create a path for the I2C device
Append the I2C slave path to the I2C master controller path.
@param[in] I2cDeviceContext Address of an I2C_DEVICE_CONTEXT structure.
@param[in] BuildControllerNode Flag to build controller node in device path.
@retval EFI_SUCCESS The I2C device path is built successfully.
@return Others It is failed to built device path.
**/
EFI_STATUS
I2cBusDevicePathAppend (
IN I2C_DEVICE_CONTEXT *I2cDeviceContext,
IN BOOLEAN BuildControllerNode
);
/**
Queue an I2C transaction for execution on the I2C device.
This routine must be called at or below TPL_NOTIFY. For synchronous
requests this routine must be called at or below TPL_CALLBACK.
This routine queues an I2C transaction to the I2C controller for
execution on the I2C bus.
When Event is NULL, QueueRequest() operates synchronously and returns
the I2C completion status as its return value.
When Event is not NULL, QueueRequest() synchronously returns EFI_SUCCESS
indicating that the asynchronous I2C transaction was queued. The values
above are returned in the buffer pointed to by I2cStatus upon the
completion of the I2C transaction when I2cStatus is not NULL.
The upper layer driver writer provides the following to the platform
vendor:
1. Vendor specific GUID for the I2C part
2. Guidance on proper construction of the slave address array when the
I2C device uses more than one slave address. The I2C bus protocol
uses the SlaveAddressIndex to perform relative to physical address
translation to access the blocks of hardware within the I2C device.
@param[in] This Pointer to an EFI_I2C_IO_PROTOCOL structure.
@param[in] SlaveAddressIndex Index value into an array of slave addresses
for the I2C device. The values in the array
are specified by the board designer, with the
third party I2C device driver writer providing
the slave address order.
For devices that have a single slave address,
this value must be zero. If the I2C device
uses more than one slave address then the
third party (upper level) I2C driver writer
needs to specify the order of entries in the
slave address array.
\ref ThirdPartyI2cDrivers "Third Party I2C
Drivers" section in I2cMaster.h.
@param[in] Event Event to signal for asynchronous transactions,
NULL for synchronous transactions
@param[in] RequestPacket Pointer to an EFI_I2C_REQUEST_PACKET structure
describing the I2C transaction
@param[out] I2cStatus Optional buffer to receive the I2C transaction
completion status
@retval EFI_SUCCESS The asynchronous transaction was successfully
queued when Event is not NULL.
@retval EFI_SUCCESS The transaction completed successfully when
Event is NULL.
@retval EFI_ABORTED The request did not complete because the driver
binding Stop() routine was called.
@retval EFI_BAD_BUFFER_SIZE The RequestPacket->LengthInBytes value is too
large.
@retval EFI_DEVICE_ERROR There was an I2C error (NACK) during the
transaction.
@retval EFI_INVALID_PARAMETER RequestPacket is NULL
@retval EFI_NOT_FOUND Reserved bit set in the SlaveAddress parameter
@retval EFI_NO_MAPPING The EFI_I2C_HOST_PROTOCOL could not set the
bus configuration required to access this I2C
device.
@retval EFI_NO_RESPONSE The I2C device is not responding to the slave
address selected by SlaveAddressIndex.
EFI_DEVICE_ERROR will be returned if the
controller cannot distinguish when the NACK
occurred.
@retval EFI_OUT_OF_RESOURCES Insufficient memory for I2C transaction
@retval EFI_UNSUPPORTED The controller does not support the requested
transaction.
**/
EFI_STATUS
EFIAPI
I2cBusQueueRequest (
IN CONST EFI_I2C_IO_PROTOCOL *This,
IN UINTN SlaveAddressIndex,
IN EFI_EVENT Event OPTIONAL,
IN EFI_I2C_REQUEST_PACKET *RequestPacket,
OUT EFI_STATUS *I2cStatus OPTIONAL
);
/**
Tests to see if this driver supports a given controller. If a child device is provided,
it further tests to see if this driver supports creating a handle for the specified child device.
This function checks to see if the driver specified by This supports the device specified by
ControllerHandle. Drivers will typically use the device path attached to
ControllerHandle and/or the services from the bus I/O abstraction attached to
ControllerHandle to determine if the driver supports ControllerHandle. This function
may be called many times during platform initialization. In order to reduce boot times, the tests
performed by this function must be very small, and take as little time as possible to execute. This
function must not change the state of any hardware devices, and this function must be aware that the
device specified by ControllerHandle may already be managed by the same driver or a
different driver. This function must match its calls to AllocatePages() with FreePages(),
AllocatePool() with FreePool(), and OpenProtocol() with CloseProtocol().
Since ControllerHandle may have been previously started by the same driver, if a protocol is
already in the opened state, then it must not be closed with CloseProtocol(). This is required
to guarantee the state of ControllerHandle is not modified by this function.
@param[in] This A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
@param[in] ControllerHandle The handle of the controller to test. This handle
must support a protocol interface that supplies
an I/O abstraction to the driver.
@param[in] RemainingDevicePath A pointer to the remaining portion of a device path. This
parameter is ignored by device drivers, and is optional for bus
drivers. For bus drivers, if this parameter is not NULL, then
the bus driver must determine if the bus controller specified
by ControllerHandle and the child controller specified
by RemainingDevicePath are both supported by this
bus driver.
@retval EFI_SUCCESS The device specified by ControllerHandle and
RemainingDevicePath is supported by the driver specified by This.
@retval EFI_ALREADY_STARTED The device specified by ControllerHandle and
RemainingDevicePath is already being managed by the driver
specified by This.
@retval EFI_ACCESS_DENIED The device specified by ControllerHandle and
RemainingDevicePath is already being managed by a different
driver or an application that requires exclusive access.
Currently not implemented.
@retval EFI_UNSUPPORTED The device specified by ControllerHandle and
RemainingDevicePath is not supported by the driver specified by This.
**/
EFI_STATUS
EFIAPI
I2cBusDriverSupported (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE Controller,
IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath
);
/**
Starts a device controller or a bus controller.
The Start() function is designed to be invoked from the EFI boot service ConnectController().
As a result, much of the error checking on the parameters to Start() has been moved into this
common boot service. It is legal to call Start() from other locations,
but the following calling restrictions must be followed or the system behavior will not be deterministic.
1. ControllerHandle must be a valid EFI_HANDLE.
2. If RemainingDevicePath is not NULL, then it must be a pointer to a naturally aligned
EFI_DEVICE_PATH_PROTOCOL.
3. Prior to calling Start(), the Supported() function for the driver specified by This must
have been called with the same calling parameters, and Supported() must have returned EFI_SUCCESS.
@param[in] This A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
@param[in] ControllerHandle The handle of the controller to start. This handle
must support a protocol interface that supplies
an I/O abstraction to the driver.
@param[in] RemainingDevicePath A pointer to the remaining portion of a device path. This
parameter is ignored by device drivers, and is optional for bus
drivers. For a bus driver, if this parameter is NULL, then handles
for all the children of Controller are created by this driver.
If this parameter is not NULL and the first Device Path Node is
not the End of Device Path Node, then only the handle for the
child device specified by the first Device Path Node of
RemainingDevicePath is created by this driver.
If the first Device Path Node of RemainingDevicePath is
the End of Device Path Node, no child handle is created by this
driver.
@retval EFI_SUCCESS The device was started.
@retval EFI_DEVICE_ERROR The device could not be started due to a device error.Currently not implemented.
@retval EFI_OUT_OF_RESOURCES The request could not be completed due to a lack of resources.
@retval Others The driver failed to start the device.
**/
EFI_STATUS
EFIAPI
I2cBusDriverStart (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE Controller,
IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath
);
/**
Stops a device controller or a bus controller.
The Stop() function is designed to be invoked from the EFI boot service DisconnectController().
As a result, much of the error checking on the parameters to Stop() has been moved
into this common boot service. It is legal to call Stop() from other locations,
but the following calling restrictions must be followed or the system behavior will not be deterministic.
1. ControllerHandle must be a valid EFI_HANDLE that was used on a previous call to this
same driver's Start() function.
2. The first NumberOfChildren handles of ChildHandleBuffer must all be a valid
EFI_HANDLE. In addition, all of these handles must have been created in this driver's
Start() function, and the Start() function must have called OpenProtocol() on
ControllerHandle with an Attribute of EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER.
@param[in] This A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
@param[in] ControllerHandle A handle to the device being stopped. The handle must
support a bus specific I/O protocol for the driver
to use to stop the device.
@param[in] NumberOfChildren The number of child device handles in ChildHandleBuffer.
@param[in] ChildHandleBuffer An array of child handles to be freed. May be NULL
if NumberOfChildren is 0.
@retval EFI_SUCCESS The device was stopped.
@retval EFI_DEVICE_ERROR The device could not be stopped due to a device error.
**/
EFI_STATUS
EFIAPI
I2cBusDriverStop (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE Controller,
IN UINTN NumberOfChildren,
IN EFI_HANDLE *ChildHandleBuffer
);
/**
Retrieves a Unicode string that is the user readable name of the driver.
This function retrieves the user readable name of a driver in the form of a
Unicode string. If the driver specified by This has a user readable name in
the language specified by Language, then a pointer to the driver name is
returned in DriverName, and EFI_SUCCESS is returned. If the driver specified
by This does not support the language specified by Language,
then EFI_UNSUPPORTED is returned.
@param This[in] A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or
EFI_COMPONENT_NAME_PROTOCOL instance.
@param Language[in] A pointer to a Null-terminated ASCII string
array indicating the language. This is the
language of the driver name that the caller is
requesting, and it must match one of the
languages specified in SupportedLanguages. The
number of languages supported by a driver is up
to the driver writer. Language is specified
in RFC 4646 or ISO 639-2 language code format.
@param DriverName[out] A pointer to the Unicode string to return.
This Unicode string is the name of the
driver specified by This in the language
specified by Language.
@retval EFI_SUCCESS The Unicode string for the Driver specified by
This and the language specified by Language was
returned in DriverName.
@retval EFI_INVALID_PARAMETER Language is NULL.
@retval EFI_INVALID_PARAMETER DriverName is NULL.
@retval EFI_UNSUPPORTED The driver specified by This does not support
the language specified by Language.
**/
EFI_STATUS
EFIAPI
I2cBusComponentNameGetDriverName (
IN EFI_COMPONENT_NAME2_PROTOCOL *This,
IN CHAR8 *Language,
OUT CHAR16 **DriverName
);
/**
Retrieves a Unicode string that is the user readable name of the controller
that is being managed by a driver.
This function retrieves the user readable name of the controller specified by
ControllerHandle and ChildHandle in the form of a Unicode string. If the
driver specified by This has a user readable name in the language specified by
Language, then a pointer to the controller name is returned in ControllerName,
and EFI_SUCCESS is returned. If the driver specified by This is not currently
managing the controller specified by ControllerHandle and ChildHandle,
then EFI_UNSUPPORTED is returned. If the driver specified by This does not
support the language specified by Language, then EFI_UNSUPPORTED is returned.
@param This[in] A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or
EFI_COMPONENT_NAME_PROTOCOL instance.
@param ControllerHandle[in] The handle of a controller that the driver
specified by This is managing. This handle
specifies the controller whose name is to be
returned.
@param ChildHandle[in] The handle of the child controller to retrieve
the name of. This is an optional parameter that
may be NULL. It will be NULL for device
drivers. It will also be NULL for a bus drivers
that wish to retrieve the name of the bus
controller. It will not be NULL for a bus
driver that wishes to retrieve the name of a
child controller.
@param Language[in] A pointer to a Null-terminated ASCII string
array indicating the language. This is the
language of the driver name that the caller is
requesting, and it must match one of the
languages specified in SupportedLanguages. The
number of languages supported by a driver is up
to the driver writer. Language is specified in
RFC 4646 or ISO 639-2 language code format.
@param ControllerName[out] A pointer to the Unicode string to return.
This Unicode string is the name of the
controller specified by ControllerHandle and
ChildHandle in the language specified by
Language from the point of view of the driver
specified by This.
@retval EFI_SUCCESS The Unicode string for the user readable name in
the language specified by Language for the
driver specified by This was returned in
DriverName.
@retval EFI_INVALID_PARAMETER ControllerHandle is NULL.
@retval EFI_INVALID_PARAMETER ChildHandle is not NULL and it is not a valid
EFI_HANDLE.
@retval EFI_INVALID_PARAMETER Language is NULL.
@retval EFI_INVALID_PARAMETER ControllerName is NULL.
@retval EFI_UNSUPPORTED The driver specified by This is not currently
managing the controller specified by
ControllerHandle and ChildHandle.
@retval EFI_UNSUPPORTED The driver specified by This does not support
the language specified by Language.
**/
EFI_STATUS
EFIAPI
I2cBusComponentNameGetControllerName (
IN EFI_COMPONENT_NAME2_PROTOCOL *This,
IN EFI_HANDLE ControllerHandle,
IN EFI_HANDLE ChildHandle OPTIONAL,
IN CHAR8 *Language,
OUT CHAR16 **ControllerName
);
/**
The user entry point for the I2C bus module. The user code starts with
this function.
@param[in] ImageHandle The firmware allocated handle for the EFI image.
@param[in] SystemTable A pointer to the EFI System Table.
@retval EFI_SUCCESS The entry point is executed successfully.
@retval other Some error occurs when executing this entry point.
**/
EFI_STATUS
EFIAPI
InitializeI2cBus(
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
);
/**
This is the unload handle for I2C bus module.
Disconnect the driver specified by ImageHandle from all the devices in the handle database.
Uninstall all the protocols installed in the driver entry point.
@param[in] ImageHandle The drivers' driver image.
@retval EFI_SUCCESS The image is unloaded.
@retval Others Failed to unload the image.
**/
EFI_STATUS
EFIAPI
I2cBusUnload (
IN EFI_HANDLE ImageHandle
);
/**
Release all the resources allocated for the I2C device.
This function releases all the resources allocated for the I2C device.
@param I2cDeviceContext The I2C child device involved for the operation.
**/
VOID
ReleaseI2cDeviceContext (
IN I2C_DEVICE_CONTEXT *I2cDeviceContext
);
/**
Complete the current request
@param[in] I2cHost Address of an I2C_HOST_CONTEXT structure.
@param[in] Status Status of the I<sub>2</sub>C operation.
@return This routine returns the input status value.
**/
EFI_STATUS
I2cHostRequestComplete (
I2C_HOST_CONTEXT *I2cHost,
EFI_STATUS Status
);
/**
Enable access to the I2C bus configuration
@param[in] I2cHostContext Address of an I2C_HOST_CONTEXT structure
@retval EFI_SUCCESS The operation completed successfully.
@retval EFI_ABORTED The request did not complete because the driver
was shutdown.
@retval EFI_BAD_BUFFER_SIZE The WriteBytes or ReadBytes buffer size is too large.
@retval EFI_DEVICE_ERROR There was an I2C error (NACK) during the operation.
This could indicate the slave device is not present.
@retval EFI_INVALID_PARAMETER RequestPacket is NULL
@retval EFI_NO_MAPPING Invalid I2cBusConfiguration value
@retval EFI_NO_RESPONSE The I2C device is not responding to the
slave address. EFI_DEVICE_ERROR may also be
returned if the controller can not distinguish
when the NACK occurred.
@retval EFI_NOT_FOUND I2C slave address exceeds maximum address
@retval EFI_NOT_READY I2C bus is busy or operation pending, wait for
the event and then read status.
@retval EFI_OUT_OF_RESOURCES Insufficient memory for I2C operation
@retval EFI_TIMEOUT The transaction did not complete within an internally
specified timeout period.
**/
EFI_STATUS
I2cHostRequestEnable (
I2C_HOST_CONTEXT *I2cHost
);
/**
Tests to see if this driver supports a given controller. If a child device is provided,
it further tests to see if this driver supports creating a handle for the specified child device.
This function checks to see if the driver specified by This supports the device specified by
ControllerHandle. Drivers will typically use the device path attached to
ControllerHandle and/or the services from the bus I/O abstraction attached to
ControllerHandle to determine if the driver supports ControllerHandle. This function
may be called many times during platform initialization. In order to reduce boot times, the tests
performed by this function must be very small, and take as little time as possible to execute. This
function must not change the state of any hardware devices, and this function must be aware that the
device specified by ControllerHandle may already be managed by the same driver or a
different driver. This function must match its calls to AllocatePages() with FreePages(),
AllocatePool() with FreePool(), and OpenProtocol() with CloseProtocol().
Since ControllerHandle may have been previously started by the same driver, if a protocol is
already in the opened state, then it must not be closed with CloseProtocol(). This is required
to guarantee the state of ControllerHandle is not modified by this function.
@param[in] This A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
@param[in] ControllerHandle The handle of the controller to test. This handle
must support a protocol interface that supplies
an I/O abstraction to the driver.
@param[in] RemainingDevicePath A pointer to the remaining portion of a device path. This
parameter is ignored by device drivers, and is optional for bus
drivers. For bus drivers, if this parameter is not NULL, then
the bus driver must determine if the bus controller specified
by ControllerHandle and the child controller specified
by RemainingDevicePath are both supported by this
bus driver.
@retval EFI_SUCCESS The device specified by ControllerHandle and
RemainingDevicePath is supported by the driver specified by This.
@retval EFI_ALREADY_STARTED The device specified by ControllerHandle and
RemainingDevicePath is already being managed by the driver
specified by This.
@retval EFI_ACCESS_DENIED The device specified by ControllerHandle and
RemainingDevicePath is already being managed by a different
driver or an application that requires exclusive access.
Currently not implemented.
@retval EFI_UNSUPPORTED The device specified by ControllerHandle and
RemainingDevicePath is not supported by the driver specified by This.
**/
EFI_STATUS
EFIAPI
I2cHostDriverSupported (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE Controller,
IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath
);
/**
Starts a device controller or a bus controller.
The Start() function is designed to be invoked from the EFI boot service ConnectController().
As a result, much of the error checking on the parameters to Start() has been moved into this
common boot service. It is legal to call Start() from other locations,
but the following calling restrictions must be followed, or the system behavior will not be deterministic.
1. ControllerHandle must be a valid EFI_HANDLE.
2. If RemainingDevicePath is not NULL, then it must be a pointer to a naturally aligned
EFI_DEVICE_PATH_PROTOCOL.
3. Prior to calling Start(), the Supported() function for the driver specified by This must
have been called with the same calling parameters, and Supported() must have returned EFI_SUCCESS.
@param[in] This A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
@param[in] ControllerHandle The handle of the controller to start. This handle
must support a protocol interface that supplies
an I/O abstraction to the driver.
@param[in] RemainingDevicePath A pointer to the remaining portion of a device path. This
parameter is ignored by device drivers, and is optional for bus
drivers. For a bus driver, if this parameter is NULL, then handles
for all the children of Controller are created by this driver.
If this parameter is not NULL and the first Device Path Node is
not the End of Device Path Node, then only the handle for the
child device specified by the first Device Path Node of
RemainingDevicePath is created by this driver.
If the first Device Path Node of RemainingDevicePath is
the End of Device Path Node, no child handle is created by this
driver.
@retval EFI_SUCCESS The device was started.
@retval EFI_DEVICE_ERROR The device could not be started due to a device error.Currently not implemented.
@retval EFI_OUT_OF_RESOURCES The request could not be completed due to a lack of resources.
@retval Others The driver failed to start the device.
**/
EFI_STATUS
EFIAPI
I2cHostDriverStart (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE Controller,
IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath
);
/**
Stops a device controller or a bus controller.
The Stop() function is designed to be invoked from the EFI boot service DisconnectController().
As a result, much of the error checking on the parameters to Stop() has been moved
into this common boot service. It is legal to call Stop() from other locations,
but the following calling restrictions must be followed, or the system behavior will not be deterministic.
1. ControllerHandle must be a valid EFI_HANDLE that was used on a previous call to this
same driver's Start() function.
2. The first NumberOfChildren handles of ChildHandleBuffer must all be a valid
EFI_HANDLE. In addition, all of these handles must have been created in this driver's
Start() function, and the Start() function must have called OpenProtocol() on
ControllerHandle with an Attribute of EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER.
@param[in] This A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
@param[in] ControllerHandle A handle to the device being stopped. The handle must
support a bus specific I/O protocol for the driver
to use to stop the device.
@param[in] NumberOfChildren The number of child device handles in ChildHandleBuffer.
@param[in] ChildHandleBuffer An array of child handles to be freed. May be NULL
if NumberOfChildren is 0.
@retval EFI_SUCCESS The device was stopped.
@retval EFI_DEVICE_ERROR The device could not be stopped due to a device error.
**/
EFI_STATUS
EFIAPI
I2cHostDriverStop (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE Controller,
IN UINTN NumberOfChildren,
IN EFI_HANDLE *ChildHandleBuffer
);
/**
Retrieves a Unicode string that is the user readable name of the driver.
This function retrieves the user readable name of a driver in the form of a
Unicode string. If the driver specified by This has a user readable name in
the language specified by Language, then a pointer to the driver name is
returned in DriverName, and EFI_SUCCESS is returned. If the driver specified
by This does not support the language specified by Language,
then EFI_UNSUPPORTED is returned.
@param This[in] A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or
EFI_COMPONENT_NAME_PROTOCOL instance.
@param Language[in] A pointer to a Null-terminated ASCII string
array indicating the language. This is the
language of the driver name that the caller is
requesting, and it must match one of the
languages specified in SupportedLanguages. The
number of languages supported by a driver is up
to the driver writer. Language is specified
in RFC 4646 or ISO 639-2 language code format.
@param DriverName[out] A pointer to the Unicode string to return.
This Unicode string is the name of the
driver specified by This in the language
specified by Language.
@retval EFI_SUCCESS The Unicode string for the Driver specified by
This and the language specified by Language was
returned in DriverName.
@retval EFI_INVALID_PARAMETER Language is NULL.
@retval EFI_INVALID_PARAMETER DriverName is NULL.
@retval EFI_UNSUPPORTED The driver specified by This does not support
the language specified by Language.
**/
EFI_STATUS
EFIAPI
I2cHostComponentNameGetDriverName (
IN EFI_COMPONENT_NAME2_PROTOCOL *This,
IN CHAR8 *Language,
OUT CHAR16 **DriverName
);
/**
Retrieves a Unicode string that is the user readable name of the controller
that is being managed by a driver.
This function retrieves the user readable name of the controller specified by
ControllerHandle and ChildHandle in the form of a Unicode string. If the
driver specified by This has a user readable name in the language specified by
Language, then a pointer to the controller name is returned in ControllerName,
and EFI_SUCCESS is returned. If the driver specified by This is not currently
managing the controller specified by ControllerHandle and ChildHandle,
then EFI_UNSUPPORTED is returned. If the driver specified by This does not
support the language specified by Language, then EFI_UNSUPPORTED is returned.
@param This[in] A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or
EFI_COMPONENT_NAME_PROTOCOL instance.
@param ControllerHandle[in] The handle of a controller that the driver
specified by This is managing. This handle
specifies the controller whose name is to be
returned.
@param ChildHandle[in] The handle of the child controller to retrieve
the name of. This is an optional parameter that
may be NULL. It will be NULL for device
drivers. It will also be NULL for a bus drivers
that wish to retrieve the name of the bus
controller. It will not be NULL for a bus
driver that wishes to retrieve the name of a
child controller.
@param Language[in] A pointer to a Null-terminated ASCII string
array indicating the language. This is the
language of the driver name that the caller is
requesting, and it must match one of the
languages specified in SupportedLanguages. The
number of languages supported by a driver is up
to the driver writer. Language is specified in
RFC 4646 or ISO 639-2 language code format.
@param ControllerName[out] A pointer to the Unicode string to return.
This Unicode string is the name of the
controller specified by ControllerHandle and
ChildHandle in the language specified by
Language from the point of view of the driver
specified by This.
@retval EFI_SUCCESS The Unicode string for the user readable name in
the language specified by Language for the
driver specified by This was returned in
DriverName.
@retval EFI_INVALID_PARAMETER ControllerHandle is NULL.
@retval EFI_INVALID_PARAMETER ChildHandle is not NULL and it is not a valid
EFI_HANDLE.
@retval EFI_INVALID_PARAMETER Language is NULL.
@retval EFI_INVALID_PARAMETER ControllerName is NULL.
@retval EFI_UNSUPPORTED The driver specified by This is not currently
managing the controller specified by
ControllerHandle and ChildHandle.
@retval EFI_UNSUPPORTED The driver specified by This does not support
the language specified by Language.
**/
EFI_STATUS
EFIAPI
I2cHostComponentNameGetControllerName (
IN EFI_COMPONENT_NAME2_PROTOCOL *This,
IN EFI_HANDLE ControllerHandle,
IN EFI_HANDLE ChildHandle OPTIONAL,
IN CHAR8 *Language,
OUT CHAR16 **ControllerName
);
/**
Handle the bus available event
This routine is called at TPL_I2C_SYNC.
@param[in] Event Address of an EFI_EVENT handle
@param[in] Context Address of an I2C_HOST_CONTEXT structure
**/
VOID
EFIAPI
I2cHostRequestCompleteEvent (
IN EFI_EVENT Event,
IN VOID *Context
);
/**
Handle the I2C bus configuration available event
This routine is called at TPL_I2C_SYNC.
@param[in] Event Address of an EFI_EVENT handle
@param[in] Context Address of an I2C_HOST_CONTEXT structure
**/
VOID
EFIAPI
I2cHostI2cBusConfigurationAvailable (
IN EFI_EVENT Event,
IN VOID *Context
);
/**
Queue an I2C operation for execution on the I2C controller.
This routine must be called at or below TPL_NOTIFY. For synchronous
requests this routine must be called at or below TPL_CALLBACK.
N.B. The typical consumers of this API are the I2C bus driver and
on rare occasions the I2C test application. Extreme care must be
taken by other consumers of this API to prevent confusing the
third party I2C drivers due to a state change at the I2C device
which the third party I2C drivers did not initiate. I2C platform
drivers may use this API within these guidelines.
This layer uses the concept of I2C bus configurations to describe
the I2C bus. An I2C bus configuration is defined as a unique
setting of the multiplexers and switches in the I2C bus which
enable access to one or more I2C devices. When using a switch
to divide a bus, due to speed differences, the I2C platform layer
would define an I2C bus configuration for the I2C devices on each
side of the switch. When using a multiplexer, the I2C platform
layer defines an I2C bus configuration for each of the selector
values required to control the multiplexer. See Figure 1 in the
<a href="http://www.nxp.com/documents/user_manual/UM10204.pdf">I<sup>2</sup>C
Specification</a> for a complex I2C bus configuration.
The I2C host driver processes all operations in FIFO order. Prior to
performing the operation, the I2C host driver calls the I2C platform
driver to reconfigure the switches and multiplexers in the I2C bus
enabling access to the specified I2C device. The I2C platform driver
also selects the maximum bus speed for the device. After the I2C bus
is configured, the I2C host driver calls the I2C port driver to
initialize the I2C controller and start the I2C operation.
@param[in] This Address of an EFI_I2C_HOST_PROTOCOL instance.
@param[in] I2cBusConfiguration I2C bus configuration to access the I2C
device.
@param[in] SlaveAddress Address of the device on the I2C bus.
@param[in] Event Event to set for asynchronous operations,
NULL for synchronous operations
@param[in] RequestPacket Address of an EFI_I2C_REQUEST_PACKET
structure describing the I2C operation
@param[out] I2cStatus Optional buffer to receive the I2C operation
completion status
@retval EFI_SUCCESS The operation completed successfully.
@retval EFI_ABORTED The request did not complete because the driver
was shutdown.
@retval EFI_BAD_BUFFER_SIZE The WriteBytes or ReadBytes buffer size is too large.
@retval EFI_DEVICE_ERROR There was an I2C error (NACK) during the operation.
This could indicate the slave device is not present.
@retval EFI_INVALID_PARAMETER RequestPacket is NULL
@retval EFI_INVALID_PARAMETER TPL is too high
@retval EFI_NO_MAPPING Invalid I2cBusConfiguration value
@retval EFI_NO_RESPONSE The I2C device is not responding to the
slave address. EFI_DEVICE_ERROR may also be
returned if the controller can not distinguish
when the NACK occurred.
@retval EFI_NOT_FOUND I2C slave address exceeds maximum address
@retval EFI_NOT_READY I2C bus is busy or operation pending, wait for
the event and then read status pointed to by
the request packet.
@retval EFI_OUT_OF_RESOURCES Insufficient memory for I2C operation
@retval EFI_TIMEOUT The transaction did not complete within an internally
specified timeout period.
**/
EFI_STATUS
EFIAPI
I2cHostQueueRequest (
IN CONST EFI_I2C_HOST_PROTOCOL *This,
IN UINTN I2cBusConfiguration,
IN UINTN SlaveAddress,
IN EFI_EVENT Event OPTIONAL,
IN EFI_I2C_REQUEST_PACKET *RequestPacket,
OUT EFI_STATUS *I2cStatus OPTIONAL
);
/**
The user Entry Point for I2C host module. The user code starts with this function.
@param[in] ImageHandle The firmware allocated handle for the EFI image.
@param[in] SystemTable A pointer to the EFI System Table.
@retval EFI_SUCCESS The entry point is executed successfully.
@retval other Some error occurs when executing this entry point.
**/
EFI_STATUS
EFIAPI
InitializeI2cHost(
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
);
/**
This is the unload handle for I2C host module.
Disconnect the driver specified by ImageHandle from all the devices in the handle database.
Uninstall all the protocols installed in the driver entry point.
@param[in] ImageHandle The drivers' driver image.
@retval EFI_SUCCESS The image is unloaded.
@retval Others Failed to unload the image.
**/
EFI_STATUS
EFIAPI
I2cHostUnload (
IN EFI_HANDLE ImageHandle
);
#endif // __I2C_DXE_H__
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