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path: root/MdePkg/Include/Protocol/I2cIo.h
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 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166  /** @file I2C I/O Protocol as defined in the PI 1.3 specification. The EFI I2C I/O protocol enables the user to manipulate a single I2C device independent of the host controller and I2C design. Copyright (c) 2013 - 2018, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent @par Revision Reference: This protocol is from PI Version 1.3. **/ #ifndef __I2C_IO_H__ #define __I2C_IO_H__ #include #define EFI_I2C_IO_PROTOCOL_GUID { 0xb60a3e6b, 0x18c4, 0x46e5, { 0xa2, 0x9a, 0xc9, 0xa1, 0x06, 0x65, 0xa2, 0x8e }} /// /// I2C I/O protocol /// /// The I2C IO protocol enables access to a specific device on the I2C /// bus. /// /// Each I2C device is identified uniquely in the system by the tuple /// DeviceGuid:DeviceIndex. The DeviceGuid represents the manufacture /// and part number and is provided by the silicon vendor or the third /// party I2C device driver writer. The DeviceIndex identifies the part /// within the system by using a unique number and is created by the /// board designer or the writer of the EFI_I2C_ENUMERATE_PROTOCOL. /// /// I2C slave addressing is abstracted to validate addresses and limit /// operation to the specified I2C device. The third party providing /// the I2C device support provides an ordered list of slave addresses /// for the I2C device required to implement the EFI_I2C_ENUMERATE_PROTOCOL. /// The order of the list must be preserved. /// typedef struct _EFI_I2C_IO_PROTOCOL EFI_I2C_IO_PROTOCOL; /** 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_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_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. **/ typedef EFI_STATUS (EFIAPI *EFI_I2C_IO_PROTOCOL_QUEUE_REQUEST) ( 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 ); /// /// I2C I/O protocol /// struct _EFI_I2C_IO_PROTOCOL { /// /// Queue an I2C transaction for execution on the I2C device. /// EFI_I2C_IO_PROTOCOL_QUEUE_REQUEST QueueRequest; /// /// Unique value assigned by the silicon manufacture or the third /// party I2C driver writer for the I2C part. This value logically /// combines both the manufacture name and the I2C part number into /// a single value specified as a GUID. /// CONST EFI_GUID *DeviceGuid; /// /// Unique ID of the I2C part within the system /// UINT32 DeviceIndex; /// /// Hardware revision - ACPI _HRV value. See the Advanced Configuration /// and Power Interface Specification, Revision 5.0 for the field format /// and the Plug and play support for I2C web-page for restriction on values. /// UINT32 HardwareRevision; /// /// Pointer to an EFI_I2C_CONTROLLER_CAPABILITIES data structure containing /// the capabilities of the I2C host controller. /// CONST EFI_I2C_CONTROLLER_CAPABILITIES *I2cControllerCapabilities; }; /// /// Reference to variable defined in the .DEC file /// extern EFI_GUID gEfiI2cIoProtocolGuid; #endif // __I2C_IO_H__