228f7bf4a0b88d784f77c45d27fa90173c987645
[mirror_edk2.git] / MdePkg / Include / Protocol / I2cIo.h
1 /** @file
2 I2C I/O Protocol as defined in the PI 1.3 specification.
3
4 The EFI I2C I/O protocol enables the user to manipulate a single
5 I2C device independent of the host controller and I2C design.
6
7 Copyright (c) 2013, Intel Corporation. All rights reserved.<BR>
8 This program and the accompanying materials
9 are licensed and made available under the terms and conditions of the BSD License
10 which accompanies this distribution. The full text of the license may be found at
11 http://opensource.org/licenses/bsd-license.php
12
13 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
14 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
15
16 @par Revision Reference:
17 This protocol is from PI Version 1.3.
18
19 **/
20
21 #ifndef __I2C_IO_H__
22 #define __I2C_IO_H__
23
24 #include <Pi/PiI2c.h>
25
26 #define EFI_I2C_IO_PROTOCOL_GUID { 0xb60a3e6b, 0x18c4, 0x46e5, { 0xa2, 0x9a, 0xc9, 0xa1, 0x06, 0x65, 0xa2, 0x8e }}
27
28 ///
29 /// I2C I/O protocol
30 ///
31 /// The I2C IO protocol enables access to a specific device on the I2C
32 /// bus.
33 ///
34 /// Each I2C device is identified uniquely in the system by the tuple
35 /// DeviceGuid:DeviceIndex. The DeviceGuid represents the manufacture
36 /// and part number and is provided by the silicon vendor or the third
37 /// party I2C device driver writer. The DeviceIndex identifies the part
38 /// within the system by using a unique number and is created by the
39 /// board designer or the writer of the EFI_I2C_ENUMERATE_PROTOCOL.
40 ///
41 /// I2C slave addressing is abstracted to validate addresses and limit
42 /// operation to the specified I2C device. The third party providing
43 /// the I2C device support provides an ordered list of slave addresses
44 /// for the I2C device required to implement the EFI_I2C_ENUMERATE_PROTOCOL.
45 /// The order of the list must be preserved.
46 ///
47 typedef struct _EFI_I2C_IO_PROTOCOL EFI_I2C_IO_PROTOCOL;
48
49
50 /**
51 Queue an I2C transaction for execution on the I2C device.
52
53 This routine must be called at or below TPL_NOTIFY. For synchronous
54 requests this routine must be called at or below TPL_CALLBACK.
55
56 This routine queues an I2C transaction to the I2C controller for
57 execution on the I2C bus.
58
59 When Event is NULL, QueueRequest() operates synchronously and returns
60 the I2C completion status as its return value.
61
62 When Event is not NULL, QueueRequest() synchronously returns EFI_SUCCESS
63 indicating that the asynchronous I2C transaction was queued. The values
64 above are returned in the buffer pointed to by I2cStatus upon the
65 completion of the I2C transaction when I2cStatus is not NULL.
66
67 The upper layer driver writer provides the following to the platform
68 vendor:
69
70 1. Vendor specific GUID for the I2C part
71 2. Guidance on proper construction of the slave address array when the
72 I2C device uses more than one slave address. The I2C bus protocol
73 uses the SlaveAddressIndex to perform relative to physical address
74 translation to access the blocks of hardware within the I2C device.
75
76 @param[in] This Pointer to an EFI_I2C_IO_PROTOCOL structure.
77 @param[in] SlaveAddressIndex Index value into an array of slave addresses
78 for the I2C device. The values in the array
79 are specified by the board designer, with the
80 third party I2C device driver writer providing
81 the slave address order.
82
83 For devices that have a single slave address,
84 this value must be zero. If the I2C device
85 uses more than one slave address then the
86 third party (upper level) I2C driver writer
87 needs to specify the order of entries in the
88 slave address array.
89
90 \ref ThirdPartyI2cDrivers "Third Party I2C
91 Drivers" section in I2cMaster.h.
92 @param[in] Event Event to signal for asynchronous transactions,
93 NULL for synchronous transactions
94 @param[in] RequestPacket Pointer to an EFI_I2C_REQUEST_PACKET structure
95 describing the I2C transaction
96 @param[out] I2cStatus Optional buffer to receive the I2C transaction
97 completion status
98
99 @retval EFI_SUCCESS The asynchronous transaction was successfully
100 queued when Event is not NULL.
101 @retval EFI_SUCCESS The transaction completed successfully when
102 Event is NULL.
103 @retval EFI_ABORTED The request did not complete because the driver
104 binding Stop() routine was called.
105 @retval EFI_BAD_BUFFER_SIZE The RequestPacket->LengthInBytes value is too
106 large.
107 @retval EFI_DEVICE_ERROR There was an I2C error (NACK) during the
108 transaction.
109 @retval EFI_INVALID_PARAMETER RequestPacket is NULL.
110 @retval EFI_NO_MAPPING The EFI_I2C_HOST_PROTOCOL could not set the
111 bus configuration required to access this I2C
112 device.
113 @retval EFI_NO_RESPONSE The I2C device is not responding to the slave
114 address selected by SlaveAddressIndex.
115 EFI_DEVICE_ERROR will be returned if the
116 controller cannot distinguish when the NACK
117 occurred.
118 @retval EFI_OUT_OF_RESOURCES Insufficient memory for I2C transaction
119 @retval EFI_UNSUPPORTED The controller does not support the requested
120 transaction.
121
122 **/
123 typedef
124 EFI_STATUS
125 (EFIAPI *EFI_I2C_IO_PROTOCOL_QUEUE_REQUEST) (
126 IN CONST EFI_I2C_IO_PROTOCOL *This,
127 IN UINTN SlaveAddressIndex,
128 IN EFI_EVENT Event OPTIONAL,
129 IN EFI_I2C_REQUEST_PACKET *RequestPacket,
130 OUT EFI_STATUS *I2cStatus OPTIONAL
131 );
132
133 ///
134 /// I2C I/O protocol
135 ///
136 struct _EFI_I2C_IO_PROTOCOL {
137 ///
138 /// Queue an I2C transaction for execution on the I2C device.
139 ///
140 EFI_I2C_IO_PROTOCOL_QUEUE_REQUEST QueueRequest;
141
142 ///
143 /// Unique value assigned by the silicon manufacture or the third
144 /// party I2C driver writer for the I2C part. This value logically
145 /// combines both the manufacture name and the I2C part number into
146 /// a single value specified as a GUID.
147 ///
148 CONST EFI_GUID *DeviceGuid;
149
150 ///
151 /// Unique ID of the I2C part within the system
152 ///
153 UINT32 DeviceIndex;
154
155 ///
156 /// Hardware revision - ACPI _HRV value. See the Advanced Configuration
157 /// and Power Interface Specification, Revision 5.0 for the field format
158 /// and the Plug and play support for I2C web-page for restriction on values.
159 ///
160 UINT32 HardwareRevision;
161
162 ///
163 /// Pointer to an EFI_I2C_CONTROLLER_CAPABILITIES data structure containing
164 /// the capabilities of the I2C host controller.
165 ///
166 CONST EFI_I2C_CONTROLLER_CAPABILITIES *I2cControllerCapabilities;
167 };
168
169 ///
170 /// Reference to variable defined in the .DEC file
171 ///
172 extern EFI_GUID gEfiI2cIoProtocolGuid;
173
174 #endif // __I2C_IO_H__