MdePkg/Include/Protocol/I2cEnumerate.h

   1 /** @file
   2   I2C Device Enumerate Protocol as defined in the PI 1.3 specification.
   3
   4   This protocol supports the enumerations of device on the I2C bus.
   5
   6   Copyright (c) 2013 - 2018, Intel Corporation. All rights reserved.<BR>
   7   SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9   @par Revision Reference:
  10   This protocol is from PI Version 1.3.
  11
  12 **/
  13
  14 #ifndef __I2C_ENUMERATE_H__
  15 #define __I2C_ENUMERATE_H__
  16
  17 #include <Pi/PiI2c.h>
  18
  19 #define EFI_I2C_ENUMERATE_PROTOCOL_GUID  { 0xda8cd7c4, 0x1c00, 0x49e2, { 0x80, 0x3e, 0x52, 0x14, 0xe7, 0x01, 0x89, 0x4c }}
  20
  21 typedef struct _EFI_I2C_ENUMERATE_PROTOCOL EFI_I2C_ENUMERATE_PROTOCOL;
  22
  23 /**
  24   Enumerate the I2C devices
  25
  26   This function enables the caller to traverse the set of I2C devices
  27   on an I2C bus.
  28
  29   @param[in]  This              The platform data for the next device on
  30                                 the I2C bus was returned successfully.
  31   @param[in, out] Device        Pointer to a buffer containing an
  32                                 EFI_I2C_DEVICE structure.  Enumeration is
  33                                 started by setting the initial EFI_I2C_DEVICE
  34                                 structure pointer to NULL.  The buffer
  35                                 receives an EFI_I2C_DEVICE structure pointer
  36                                 to the next I2C device.
  37
  38   @retval EFI_SUCCESS           The platform data for the next device on
  39                                 the I2C bus was returned successfully.
  40   @retval EFI_INVALID_PARAMETER Device is NULL
  41   @retval EFI_NO_MAPPING        *Device does not point to a valid
  42                                 EFI_I2C_DEVICE structure returned in a
  43                                 previous call Enumerate().
  44
  45 **/
  46 typedef
  47 EFI_STATUS
  48 (EFIAPI *EFI_I2C_ENUMERATE_PROTOCOL_ENUMERATE)(
  49   IN CONST EFI_I2C_ENUMERATE_PROTOCOL *This,
  50   IN OUT CONST EFI_I2C_DEVICE         **Device
  51   );
  52
  53 /**
  54   Get the requested I2C bus frequency for a specified bus configuration.
  55
  56   This function returns the requested I2C bus clock frequency for the
  57   I2cBusConfiguration.  This routine is provided for diagnostic purposes
  58   and is meant to be called after calling Enumerate to get the
  59   I2cBusConfiguration value.
  60
  61   @param[in] This                 Pointer to an EFI_I2C_ENUMERATE_PROTOCOL
  62                                   structure.
  63   @param[in] I2cBusConfiguration  I2C bus configuration to access the I2C
  64                                   device
  65   @param[out] *BusClockHertz      Pointer to a buffer to receive the I2C
  66                                   bus clock frequency in Hertz
  67
  68   @retval EFI_SUCCESS           The I2C bus frequency was returned
  69                                 successfully.
  70   @retval EFI_INVALID_PARAMETER BusClockHertz was NULL
  71   @retval EFI_NO_MAPPING        Invalid I2cBusConfiguration value
  72
  73 **/
  74 typedef
  75 EFI_STATUS
  76 (EFIAPI *EFI_I2C_ENUMERATE_PROTOCOL_GET_BUS_FREQUENCY)(
  77   IN CONST EFI_I2C_ENUMERATE_PROTOCOL *This,
  78   IN UINTN                            I2cBusConfiguration,
  79   OUT UINTN                           *BusClockHertz
  80   );
  81
  82 ///
  83 /// I2C Enumerate protocol
  84 ///
  85 struct _EFI_I2C_ENUMERATE_PROTOCOL {
  86   ///
  87   /// Traverse the set of I2C devices on an I2C bus.  This routine
  88   /// returns the next I2C device on an I2C bus.
  89   ///
  90   EFI_I2C_ENUMERATE_PROTOCOL_ENUMERATE            Enumerate;
  91
  92   ///
  93   /// Get the requested I2C bus frequency for a specified bus
  94   /// configuration.
  95   ///
  96   EFI_I2C_ENUMERATE_PROTOCOL_GET_BUS_FREQUENCY    GetBusFrequency;
  97 };
  98
  99 ///
 100 /// Reference to variable defined in the .DEC file
 101 ///
 102 extern EFI_GUID  gEfiI2cEnumerateProtocolGuid;
 103
 104 #endif //  __I2C_ENUMERATE_H__