OvmfPkg/XenPvBlkDxe/DriverBinding.h

   1
   2 /** @file
   3   Driver Binding functions declaration for XenPvBlk driver.
   4
   5   Copyright (C) 2014, Citrix Ltd.
   6
   7   SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9 **/
  10
  11 /**
  12   Tests to see if this driver supports a given controller. If a child device is provided,
  13   it further tests to see if this driver supports creating a handle for the specified child device.
  14
  15   This function checks to see if the driver specified by This supports the device specified by
  16   ControllerHandle. Drivers will typically use the device path attached to
  17   ControllerHandle and/or the services from the bus I/O abstraction attached to
  18   ControllerHandle to determine if the driver supports ControllerHandle. This function
  19   may be called many times during platform initialization. In order to reduce boot times, the tests
  20   performed by this function must be very small, and take as little time as possible to execute. This
  21   function must not change the state of any hardware devices, and this function must be aware that the
  22   device specified by ControllerHandle may already be managed by the same driver or a
  23   different driver. This function must match its calls to AllocatePages() with FreePages(),
  24   AllocatePool() with FreePool(), and OpenProtocol() with CloseProtocol().
  25   Because ControllerHandle may have been previously started by the same driver, if a protocol is
  26   already in the opened state, then it must not be closed with CloseProtocol(). This is required
  27   to guarantee the state of ControllerHandle is not modified by this function.
  28
  29   @param[in]  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
  30   @param[in]  ControllerHandle     The handle of the controller to test. This handle
  31                                    must support a protocol interface that supplies
  32                                    an I/O abstraction to the driver.
  33   @param[in]  RemainingDevicePath  A pointer to the remaining portion of a device path.  This
  34                                    parameter is ignored by device drivers, and is optional for bus
  35                                    drivers. For bus drivers, if this parameter is not NULL, then
  36                                    the bus driver must determine if the bus controller specified
  37                                    by ControllerHandle and the child controller specified
  38                                    by RemainingDevicePath are both supported by this
  39                                    bus driver.
  40
  41   @retval EFI_SUCCESS              The device specified by ControllerHandle and
  42                                    RemainingDevicePath is supported by the driver specified by This.
  43   @retval EFI_ALREADY_STARTED      The device specified by ControllerHandle and
  44                                    RemainingDevicePath is already being managed by the driver
  45                                    specified by This.
  46   @retval EFI_ACCESS_DENIED        The device specified by ControllerHandle and
  47                                    RemainingDevicePath is already being managed by a different
  48                                    driver or an application that requires exclusive access.
  49                                    Currently not implemented.
  50   @retval EFI_UNSUPPORTED          The device specified by ControllerHandle and
  51                                    RemainingDevicePath is not supported by the driver specified by This.
  52 **/
  53 EFI_STATUS
  54 EFIAPI
  55 XenPvBlkDxeDriverBindingSupported (
  56   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
  57   IN EFI_HANDLE                   ControllerHandle,
  58   IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath OPTIONAL
  59   );
  60
  61 /**
  62   Starts a device controller or a bus controller.
  63
  64   The Start() function is designed to be invoked from the EFI boot service ConnectController().
  65   As a result, much of the error checking on the parameters to Start() has been moved into this
  66   common boot service. It is legal to call Start() from other locations,
  67   but the following calling restrictions must be followed, or the system behavior will not be deterministic.
  68   1. ControllerHandle must be a valid EFI_HANDLE.
  69   2. If RemainingDevicePath is not NULL, then it must be a pointer to a naturally aligned
  70      EFI_DEVICE_PATH_PROTOCOL.
  71   3. Prior to calling Start(), the Supported() function for the driver specified by This must
  72      have been called with the same calling parameters, and Supported() must have returned EFI_SUCCESS.
  73
  74   @param[in]  This                 A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
  75   @param[in]  ControllerHandle     The handle of the controller to start. This handle
  76                                    must support a protocol interface that supplies
  77                                    an I/O abstraction to the driver.
  78   @param[in]  RemainingDevicePath  A pointer to the remaining portion of a device path.  This
  79                                    parameter is ignored by device drivers, and is optional for bus
  80                                    drivers. For a bus driver, if this parameter is NULL, then handles
  81                                    for all the children of Controller are created by this driver.
  82                                    If this parameter is not NULL and the first Device Path Node is
  83                                    not the End of Device Path Node, then only the handle for the
  84                                    child device specified by the first Device Path Node of
  85                                    RemainingDevicePath is created by this driver.
  86                                    If the first Device Path Node of RemainingDevicePath is
  87                                    the End of Device Path Node, no child handle is created by this
  88                                    driver.
  89
  90   @retval EFI_SUCCESS              The device was started.
  91   @retval EFI_DEVICE_ERROR         The device could not be started due to a device error.Currently not implemented.
  92   @retval EFI_OUT_OF_RESOURCES     The request could not be completed due to a lack of resources.
  93   @retval Others                   The driver failded to start the device.
  94
  95 **/
  96 EFI_STATUS
  97 EFIAPI
  98 XenPvBlkDxeDriverBindingStart (
  99   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 100   IN EFI_HANDLE                   ControllerHandle,
 101   IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath OPTIONAL
 102   );
 103
 104 /**
 105   Stops a device controller or a bus controller.
 106
 107   The Stop() function is designed to be invoked from the EFI boot service DisconnectController().
 108   As a result, much of the error checking on the parameters to Stop() has been moved
 109   into this common boot service. It is legal to call Stop() from other locations,
 110   but the following calling restrictions must be followed, or the system behavior will not be deterministic.
 111   1. ControllerHandle must be a valid EFI_HANDLE that was used on a previous call to this
 112      same driver's Start() function.
 113   2. The first NumberOfChildren handles of ChildHandleBuffer must all be a valid
 114      EFI_HANDLE. In addition, all of these handles must have been created in this driver's
 115      Start() function, and the Start() function must have called OpenProtocol() on
 116      ControllerHandle with an Attribute of EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER.
 117
 118   @param[in]  This              A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
 119   @param[in]  ControllerHandle  A handle to the device being stopped. The handle must
 120                                 support a bus specific I/O protocol for the driver
 121                                 to use to stop the device.
 122   @param[in]  NumberOfChildren  The number of child device handles in ChildHandleBuffer.
 123   @param[in]  ChildHandleBuffer An array of child handles to be freed. May be NULL
 124                                 if NumberOfChildren is 0.
 125
 126   @retval EFI_SUCCESS           The device was stopped.
 127   @retval EFI_DEVICE_ERROR      The device could not be stopped due to a device error.
 128
 129 **/
 130 EFI_STATUS
 131 EFIAPI
 132 XenPvBlkDxeDriverBindingStop (
 133   IN EFI_DRIVER_BINDING_PROTOCOL  *This,
 134   IN  EFI_HANDLE                  ControllerHandle,
 135   IN  UINTN                       NumberOfChildren,
 136   IN  EFI_HANDLE                  *ChildHandleBuffer OPTIONAL
 137   );