2.8. WD_CardRegister()

Purpose

Card registration function.
The function

  • Maps the physical memory ranges to be accessed by kernel-mode processes and user-mode applications.
  • Verifies that none of the registered device resources (set in pCardReg->Card.Item) are already locked for exclusive use.
    [Note]
    A resource can be locked for exclusive use by setting the fNotSharable field of its WD_ITEMS structure (pCardReg->Card.Item[i]) to 1, before calling WD_CardRegister().
  • Saves data regarding the interrupt request (IRQ) number and the interrupt type in internal data structures; this data will later be used by InterruptEnable() [2.18] and/or WD_IntEnable() [3.2].

Prototype
DWORD WD_CardRegister(
    HANDLE hWD,
    WD_CARD_REGISTER *pCardReg);
Parameters
NameTypeInput/Output
hWDHANDLEInput
pCardRegWD_CARD_REGISTER* 
• CardWD_CARD 
 * dwItemsDWORDInput
 * ItemWD_ITEMS[WD_CARD_ITEMS] 
  • itemDWORDInput
  • fNotSharableDWORDInput
  • dwReservedDWORDN/A
  • dwOptionsDWORDInput
  • Iunion 
   * Memstruct 
    • dwPhysicalAddrDWORDInput
    • dwBytesDWORDInput
    • dwTransAddrKPTROutput
    • dwUserDirectAddrUPTROutput
    • dwCpuPhysicalAddrDWORDOutput
    • dwBarDWORDInput
   * IOstruct 
    • dwAddrKPTRInput
    • dwBytesDWORDInput
    • dwBarDWORDInput
   * Intstruct 
    • dwInterruptDWORDInput
    • dwOptionsDWORDInput
    • hInterruptDWORDOutput
   * BusWD_BUS 
    • dwBusTypeWD_BUS_TYPEInput
    • dwBusNumDWORDInput
    • dwSlotFuncDWORDInput
   * ValstructN/A
• fCheckLockOnlyDWORDInput
• hCardDWORDOutput
• dwOptionsDWORDInput
• cNameCHAR[32]Input
• cDescriptionCHAR[100]Input
Description
NameDescription
hWDHandle to WinDriver's kernel-mode driver as received from WD_Open() [5.2]
pCardRegPointer to a card registration information structure:
• Card Card information structure. For PCI and PCMCIA devices it is recommended to pass the card structure received from a previous call to WD_PciGetCardInfo() [2.3] / WD_PcmciaGetCardInfo() [2.6], respectively — refer to Remark 1 in this section.
 * dwItemsNumber of items detected on the card
 * ItemCard items information structure:
  • item Type of item. Can be ITEM_MEMORY, ITEM_IO, ITEM_INTERRUPT or ITEM_BUS.
  • fNotSharable
  • 1 — Non-sharable resource; should be locked for exclusive use
  • 0 — Sharable resource
  • dwOptions A bit-mask of item registration flags — a combination of any of the of the following WD_ITEM_OPTIONS enumeration values:
  • WD_ITEM_DO_NOT_MAP_KERNEL: Avoid mapping the item's physical memory to the kernel address space (I.Mem.dwTransAddr not set); map the memory only to the user-mode virtual address space (mapped base address: I.Mem.dwUserDirectMemAddr). For more information, refer to Remark 2 in this section.
    NOTE: This flag is applicable only to memory items.
  • WD_ITEM_ALLOW_CACHE (Windows and Windows CE): Map the item's physical memory (base address: I.Mem.dwPhysicalAddr) as cached.
    NOTE: This flag is applicable only to memory items that pertain to the host's RAM, as opposed to local memory on the card.
  • WD_ITEM_CE_MAP_VIRTUAL (Windows CE) — Perform the kernel mapping of the physical memory (mapped base address: I.Mem.dwTransAddr) to non-static virtual system addresses, as opposed to the default static kernel address mapping.
    NOTE: Do not set this flag for items that need to be accessed in kernel mode — namely, items that will be used to create interrupt transfer commands or items that will be accessed from a Kernel PlugIn driver.
    NOTE: This flag is applicable only to memory items.
  • ISpecific data according to the item type:
   * MemDescribes a memory item (item = ITEM_MEMORY):
    • dwPhysicalAddr First address of the physical memory range.
For PCI, this field is ignored and the physical address is retrieved directly from the card, because the 32-bit field size cannot correctly store 64-bit addresses.
    • dwBytesLength (in bytes) of the memory range
    • dwTransAddr Kernel-mode mapping of the memory range's physical base address.
This address should be used when setting the memory address in calls to WD_Transfer() [2.11] or WD_MultiTransfer() [2.12] or when accessing memory directly from a Kernel PlugIn driver.
    • dwUserDirectAddr User-mode mapping of the memory range's physical base address.
This address should be used for accessing a memory address directly from a user-mode process.
    • dwCpuPhysicalAddr Translation of the card's physical memory base address from bus-specific values to CPU values
    • dwBarBase Address Register number of PCI card
   * IODescribes an I/O item (item = ITEM_IO):
    • dwAddrFirst address of the I/O range
    • dwBytesLength of the I/O range, in bytes
    • dwBarBase Address Register (BAR) number for the I/O range
   * Int Describes an interrupt item (item = ITEM_INTERRUPT):
    • dwInterruptPhysical interrupt request (IRQ) number
    • dwOptions Interrupt options bit-mask, which can consist of a combination of any of the following flags:
Interrupt type flags:
NOTE: In the call to WD_CardRegister() the interrupt type flags are appliable only to ISA devices. For Plug-and-Play hardware (PCI/PCMCIA) the function retrieves the supported interrupt types independently.
INTERRUPT_LEVEL_SENSITIVE — indicates that the device supports level-sensitive interrupts.
INTERRUPT_LATCHED — indicates that the device supports legacy edge-triggered interrupts.
The value of this flag is zero, therefore it is applicable only when no other interrupt flag is set.
Miscellaneous interrupt flags:
INTERRUPT_CE_INT_ID — On Windows CE
(unlike other operating systems), there is an abstraction of the physical interrupt number to a logical one. Setting this bit will instruct WinDriver to refer to the dwInterrupt value as a logical interrupt number and convert it to a physical interrupt number.
    • hInterrupt An interrupt handle to be used in calls to InterruptEnable() [2.18] or WD_IntEnable() [3.2].
   * Bus Describes a bus item (item = ITEM_BUS):
    • dwBusType The card's bus type. Can be any of the following WD_BUS_TYPE enumeration values:
WD_BUS_PCI — PCI bus
WD_BUS_PCMCIA — PCMCIA bus
WD_BUS_ISA — ISA bus
WD_BUS_EISA — EISA bus
    • dwBusNumBus number
    • dwSlotFunc A combination of the card's bus slot/socket and function numbers: the lower three bits represent the function number and the remaining bits represent the slot/socket number. For example: a value of 0x80 (<=> 10000000 binary) corresponds to a function number of 0 (lower 3 bits: 000) and a slot/socket number of 0x10 (remaining bits: 10000).
• fCheckLockOnly Set to TRUE to check if the defined card resources can be locked (in which case hCard will be set to 1), or whether they are already locked for exclusive use. When this flag is set to TRUE the function doesn't actually locking the specified resources.
• hCard Handle to the card resources defined in the Card field. This handle should later be passed to WD_CardUnregister() [2.10] in order to free the resources. If the card registration fails, this field is set to 0.
When fCheckLockOnly is set to TRUE, hCard is set to 1 if the card's resources can be be locked successfully (i.e., the resources aren't currently locked for exclusive use), or 0 otherwise.
• dwOptions Should always be set to zero
• cName Card name (optional)
• cDescriptionCard description (optional)
Return Value

Returns WD_STATUS_SUCCESS (0) on success, or an appropriate error code otherwise [A].

Remarks
  1. For PCI/PCMCIA the cardReg.Card input resources information should be retrieved from the Plug-and-Play Manager via WD_PciGetCardInfo() [2.3] or WD_PcmciaGetCardInfo() [2.6] (respectively).
  2. If your card has a large memory range that cannot be fully mapped to the kernel address space, you can set the WD_ITEM_DO_NOT_MAP_KERNEL flag in the dwOptions field of the relevant WD_ITEMS memory resource structure that you pass to the card registration function (pCardReg->Card.Item[i].dwOptions). This flag instructs the function to map the memory range only to the user-mode virtual address space, and not to the kernel address space. (For PCI/PCMCIA devices, you can modify the relevant item in the card information structure (pCard) that you received from WD_PciGetCardInfo() [2.3] or WD_PcmciaGetCardInfo() [2.6], before passing this structure to WD_CardRegister().)

    [Note]
    Note that if you select to set the WD_ITEM_DO_NOT_MAP_KERNEL flag, WD_CardRegister() will not update the item's dwTransAddr field with a kernel mapping of the memory's base address, and you will therefore not be able to rely on this mapping in calls to WinDriver APIs — namely interrupt handling APIs or any API called from a Kernel PlugIn driver.
  3. WD_CardRegister() enables the user to map the card memory resources into virtual memory and access them as regular pointers. In Windows CE there is a security mechanism that prevents processes from accessing each other's memory space, without explicitly requesting it. This request is made using the SetProcPermissions() function, which sets the desired permissions for the current thread. Since the card resources are mapped inside WinDriver and these mappings belong to the Device Manager process, any other thread should call this function before accessing these mappings. Every call to WD_Open() calls SetProcPermissions() (see windrvr.h), so any thread that accesses mapped regions and does not call WD_Open(), such as a user thread, Windows message thread etc, should explicitly call SetProcPermissions() For more information, please refer to Microsoft's documentation. WinDriver's ThreadStart() function performs the required call to SetProcPermissions(), therefore when using ThreadStart() to create new threads you do not need to call SetProcPermissions() yourself.

Example
WD_CARD_REGISTER cardReg;
BZERO(cardReg);
cardReg.Card.dwItems = 1;
cardReg.Card.Item[0].item = ITEM_IO;
cardReg.Card.Item[0].fNotSharable = 1;
cardReg.Card.Item[0].I.IO.dwAddr = 0x378;
cardReg.Card.Item[0].I.IO.dwBytes = 8;
WD_CardRegister(hWD, &cardReg);
if (cardReg.hCard == 0)
{
    printf("Failed locking device\n");
    return FALSE;
}