/** @file

  Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>

  This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution. The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php
  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include <PiDxe.h>
#include <Library/BaseMemoryLib.h>
#include <Library/DebugLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/UefiLib.h>
#include <Protocol/I2cBusConfigurationManagement.h>
#include <Protocol/I2cEnumerate.h>
#include <Protocol/I2cMaster.h>
#include <Protocol/Mezzanine.h>

STATIC MEZZANINE_PROTOCOL     *mMezzanine;

typedef struct {
  EFI_I2C_ENUMERATE_PROTOCOL                    I2cEnumerate;
  EFI_I2C_BUS_CONFIGURATION_MANAGEMENT_PROTOCOL I2cConfigManagement;
  EFI_HANDLE                                    I2cMasterHandle;
  UINT32                                        BusFrequency;
  UINTN                                         NumDevices;
  CONST EFI_I2C_DEVICE                          *Devices;
} I2C_BUS;

STATIC
EFI_STATUS
EFIAPI
I2cEnumerate (
  IN CONST EFI_I2C_ENUMERATE_PROTOCOL *This,
  IN OUT CONST EFI_I2C_DEVICE         **Device
  )
{
  I2C_BUS     *Bus;

  if (Device == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  Bus = BASE_CR (This, I2C_BUS, I2cEnumerate);

  if (Bus->NumDevices == 0 ||
      (Bus->NumDevices > 0 && *Device == &Bus->Devices[Bus->NumDevices - 1])) {
    *Device = NULL;
  } else if (*Device == NULL) {
    *Device = &Bus->Devices[0];
  } else if (Bus->NumDevices > 1 &&
             *Device >= &Bus->Devices[0] &&
             *Device < &Bus->Devices[Bus->NumDevices - 1]) {
    ++*Device;
  } else {
    return EFI_NO_MAPPING;
  }
  return EFI_SUCCESS;
}

STATIC
EFI_STATUS
EFIAPI
I2cGetBusFrequency (
  IN CONST EFI_I2C_ENUMERATE_PROTOCOL *This,
  IN UINTN                            I2cBusConfiguration,
  OUT UINTN                           *BusClockHertz
  )
{
  I2C_BUS     *Bus;

  if (BusClockHertz == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  if (I2cBusConfiguration > 0) {
    return EFI_NO_MAPPING;
  }

  Bus = BASE_CR (This, I2C_BUS, I2cEnumerate);

  *BusClockHertz = Bus->BusFrequency;

  return EFI_SUCCESS;
}

STATIC
EFI_STATUS
EFIAPI
EnableI2cBusConfiguration (
  IN CONST EFI_I2C_BUS_CONFIGURATION_MANAGEMENT_PROTOCOL  *This,
  IN UINTN                                                I2cBusConfiguration,
  IN EFI_EVENT                                            Event       OPTIONAL,
  IN EFI_STATUS                                           *I2cStatus  OPTIONAL
  )
{
  EFI_I2C_MASTER_PROTOCOL *I2cMaster;
  EFI_STATUS              Status;
  UINTN                   BusClockHertz;
  I2C_BUS                 *Bus;

  if (I2cBusConfiguration > 0) {
    return EFI_NO_MAPPING;
  }

  Bus = BASE_CR (This, I2C_BUS, I2cConfigManagement);

  Status = gBS->HandleProtocol (Bus->I2cMasterHandle,
                  &gEfiI2cMasterProtocolGuid, (VOID **)&I2cMaster);
  if (EFI_ERROR (Status)) {
    DEBUG ((DEBUG_ERROR, "%a: gBS->HandleProtocol() failed - %r\n",
      __FUNCTION__, Status));
    return Status;
  }

  BusClockHertz = Bus->BusFrequency;
  Status = I2cMaster->SetBusFrequency (I2cMaster, &BusClockHertz);
  if (EFI_ERROR (Status)) {
    DEBUG ((DEBUG_ERROR, "%a: I2cMaster->SetBusFrequency() failed - %r\n",
      __FUNCTION__, Status));
    return Status;
  }

  if (Event != NULL) {
    *I2cStatus = EFI_SUCCESS;
    gBS->SignalEvent (Event);
  }
  return EFI_SUCCESS;
}

STATIC I2C_BUS mI2cBus0 = {
  { I2cEnumerate, I2cGetBusFrequency },
  { EnableI2cBusConfiguration },
  NULL,
  FixedPcdGet32 (PcdI2c0BusFrequencyHz),
  0,
  NULL,
};

STATIC I2C_BUS mI2cBus1 = {
  { I2cEnumerate, I2cGetBusFrequency },
  { EnableI2cBusConfiguration },
  NULL,
  FixedPcdGet32 (PcdI2c1BusFrequencyHz),
  0,
  NULL,
};

STATIC
VOID
RegisterI2cBus (
  IN  EFI_GUID                *Guid,
  IN  I2C_BUS                 *I2cBus,
  IN  UINTN                   NumDevices,
  IN  CONST EFI_I2C_DEVICE    *Devices
  )
{
  EFI_STATUS    Status;
  UINTN         BufferSize;

  BufferSize = sizeof (EFI_HANDLE);
  Status = gBS->LocateHandle (ByProtocol, Guid, NULL, &BufferSize,
                  &I2cBus->I2cMasterHandle);
  if (EFI_ERROR (Status)) {
    DEBUG ((DEBUG_INFO, "%a: gBS->LocateHandle() failed - %r\n", __FUNCTION__,
      Status));
    return;
  }

  I2cBus->NumDevices = NumDevices;
  I2cBus->Devices = Devices;

  Status = gBS->InstallMultipleProtocolInterfaces (&I2cBus->I2cMasterHandle,
                  &gEfiI2cEnumerateProtocolGuid,
                  &I2cBus->I2cEnumerate,
                  &gEfiI2cBusConfigurationManagementProtocolGuid,
                  &I2cBus->I2cConfigManagement,
                  NULL);
  ASSERT_EFI_ERROR (Status);
}

EFI_STATUS
EFIAPI
EntryPoint (
  IN EFI_HANDLE         ImageHandle,
  IN EFI_SYSTEM_TABLE   *SystemTable
  )
{
  EFI_STATUS    Status;

  Status = gBS->LocateProtocol (&g96BoardsMezzanineProtocolGuid, NULL,
                  (VOID **)&mMezzanine);
  ASSERT_EFI_ERROR (Status);

  RegisterI2cBus (&g96BoardsI2c0MasterGuid, &mI2cBus0,
    mMezzanine->I2c0NumDevices, mMezzanine->I2c0DeviceArray);
  RegisterI2cBus (&g96BoardsI2c1MasterGuid, &mI2cBus1,
    mMezzanine->I2c1NumDevices, mMezzanine->I2c1DeviceArray);

  return EFI_SUCCESS;
}