OvmfPkg/XenPvBlkDxe/DriverBinding.h

   1
   2 /** @file
   3   Driver Binding functions declaration for XenPvBlk driver.
   4
   5   Copyright (C) 2014, Citrix Ltd.
   6
   7   This program and the accompanying materials
   8   are licensed and made available under the terms and conditions of the BSD License
   9   which accompanies this distribution.  The full text of the license may be found at
  10   http://opensource.org/licenses/bsd-license.php
  11
  12   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 /**
  18   Tests to see if this driver supports a given controller. If a child device is provided,
  19   it further tests to see if this driver supports creating a handle for the specified child device.
  20
  21   This function checks to see if the driver specified by This supports the device specified by
  22   ControllerHandle. Drivers will typically use the device path attached to
  23   ControllerHandle and/or the services from the bus I/O abstraction attached to
  24   ControllerHandle to determine if the driver supports ControllerHandle. This function
  25   may be called many times during platform initialization. In order to reduce boot times, the tests
  26   performed by this function must be very small, and take as little time as possible to execute. This
  27   function must not change the state of any hardware devices, and this function must be aware that the
  28   device specified by ControllerHandle may already be managed by the same driver or a
  29   different driver. This function must match its calls to AllocatePages() with FreePages(),
  30   AllocatePool() with FreePool(), and OpenProtocol() with CloseProtocol().
  31   Because ControllerHandle may have been previously started by the same driver, if a protocol is
  32   already in the opened state, then it must not be closed with CloseProtocol(). This is required
  33   to guarantee the state of ControllerHandle is not modified by this function.
  34
  35   @param[in]  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
  36   @param[in]  ControllerHandle     The handle of the controller to test. This handle
  37                                    must support a protocol interface that supplies
  38                                    an I/O abstraction to the driver.
  39   @param[in]  RemainingDevicePath  A pointer to the remaining portion of a device path.  This
  40                                    parameter is ignored by device drivers, and is optional for bus
  41                                    drivers. For bus drivers, if this parameter is not NULL, then
  42                                    the bus driver must determine if the bus controller specified
  43                                    by ControllerHandle and the child controller specified
  44                                    by RemainingDevicePath are both supported by this
  45                                    bus driver.
  46
  47   @retval EFI_SUCCESS              The device specified by ControllerHandle and
  48                                    RemainingDevicePath is supported by the driver specified by This.
  49   @retval EFI_ALREADY_STARTED      The device specified by ControllerHandle and
  50                                    RemainingDevicePath is already being managed by the driver
  51                                    specified by This.
  52   @retval EFI_ACCESS_DENIED        The device specified by ControllerHandle and
  53                                    RemainingDevicePath is already being managed by a different
  54                                    driver or an application that requires exclusive access.
  55                                    Currently not implemented.
  56   @retval EFI_UNSUPPORTED          The device specified by ControllerHandle and
  57                                    RemainingDevicePath is not supported by the driver specified by This.
  58 **/
  59 EFI_STATUS
  60 EFIAPI
  61 XenPvBlkDxeDriverBindingSupported (
  62   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
  63   IN EFI_HANDLE                   ControllerHandle,
  64   IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath OPTIONAL
  65   );
  66
  67 /**
  68   Starts a device controller or a bus controller.
  69
  70   The Start() function is designed to be invoked from the EFI boot service ConnectController().
  71   As a result, much of the error checking on the parameters to Start() has been moved into this
  72   common boot service. It is legal to call Start() from other locations,
  73   but the following calling restrictions must be followed, or the system behavior will not be deterministic.
  74   1. ControllerHandle must be a valid EFI_HANDLE.
  75   2. If RemainingDevicePath is not NULL, then it must be a pointer to a naturally aligned
  76      EFI_DEVICE_PATH_PROTOCOL.
  77   3. Prior to calling Start(), the Supported() function for the driver specified by This must
  78      have been called with the same calling parameters, and Supported() must have returned EFI_SUCCESS.
  79
  80   @param[in]  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
  81   @param[in]  ControllerHandle     The handle of the controller to start. This handle
  82                                    must support a protocol interface that supplies
  83                                    an I/O abstraction to the driver.
  84   @param[in]  RemainingDevicePath  A pointer to the remaining portion of a device path.  This
  85                                    parameter is ignored by device drivers, and is optional for bus
  86                                    drivers. For a bus driver, if this parameter is NULL, then handles
  87                                    for all the children of Controller are created by this driver.
  88                                    If this parameter is not NULL and the first Device Path Node is
  89                                    not the End of Device Path Node, then only the handle for the
  90                                    child device specified by the first Device Path Node of
  91                                    RemainingDevicePath is created by this driver.
  92                                    If the first Device Path Node of RemainingDevicePath is
  93                                    the End of Device Path Node, no child handle is created by this
  94                                    driver.
  95
  96   @retval EFI_SUCCESS              The device was started.
  97   @retval EFI_DEVICE_ERROR         The device could not be started due to a device error.Currently not implemented.
  98   @retval EFI_OUT_OF_RESOURCES     The request could not be completed due to a lack of resources.
  99   @retval Others                   The driver failded to start the device.
 100
 101 **/
 102 EFI_STATUS
 103 EFIAPI
 104 XenPvBlkDxeDriverBindingStart (
 105   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 106   IN EFI_HANDLE                   ControllerHandle,
 107   IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath OPTIONAL
 108   );
 109
 110 /**
 111   Stops a device controller or a bus controller.
 112
 113   The Stop() function is designed to be invoked from the EFI boot service DisconnectController().
 114   As a result, much of the error checking on the parameters to Stop() has been moved
 115   into this common boot service. It is legal to call Stop() from other locations,
 116   but the following calling restrictions must be followed, or the system behavior will not be deterministic.
 117   1. ControllerHandle must be a valid EFI_HANDLE that was used on a previous call to this
 118      same driver's Start() function.
 119   2. The first NumberOfChildren handles of ChildHandleBuffer must all be a valid
 120      EFI_HANDLE. In addition, all of these handles must have been created in this driver's
 121      Start() function, and the Start() function must have called OpenProtocol() on
 122      ControllerHandle with an Attribute of EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER.
 123
 124   @param[in]  This              A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 125   @param[in]  ControllerHandle  A handle to the device being stopped. The handle must
 126                                 support a bus specific I/O protocol for the driver
 127                                 to use to stop the device.
 128   @param[in]  NumberOfChildren  The number of child device handles in ChildHandleBuffer.
 129   @param[in]  ChildHandleBuffer An array of child handles to be freed. May be NULL
 130                                 if NumberOfChildren is 0.
 131
 132   @retval EFI_SUCCESS           The device was stopped.
 133   @retval EFI_DEVICE_ERROR      The device could not be stopped due to a device error.
 134
 135 **/
 136 EFI_STATUS
 137 EFIAPI
 138 XenPvBlkDxeDriverBindingStop (
 139   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 140   IN  EFI_HANDLE                  ControllerHandle,
 141   IN  UINTN                       NumberOfChildren,
 142   IN  EFI_HANDLE                  *ChildHandleBuffer OPTIONAL
 143   );