csx_AccessConfigurationRegister - read or write a PC Card Configuration Register

#include <sys/pccard.h>
int32_t csx_AccessConfigurationRegister(client_handle_t ch,
     access_config_reg_t *acr);

illumos DDI Specific (illumos DDI)

Client handle returned from csx_RegisterClient(9F).


Pointer to an access_config_reg_t structure.

This function allows a client to read or write a PCCard Configuration Register.

The structure members of access_config_reg_t are:

uint32_t     Socket;     /* socket number*/
uint32_t     Action;     /* register access operation*/
uint32_t     Offset;     /* config register offset*/
uint32_t     Value;      /* value read or written*/

The fields are defined as follows:


Not used in illumos, but for portability with other Card Services implementations, it should be set to the logical socket number.


May be set to CONFIG_REG_READ or CONFIG_REG_WRITE. All other values in the Action field are reserved for future use. If the Action field is set to CONFIG_REG_WRITE, the Value field is written to the specified configuration register. Card Services does not read the configuration register after a write operation. For that reason, the Value field is only updated by a CONFIG_REG_READ request.


Specifies the byte offset for the desired configuration register from the PC Card configuration register base specified in csx_RequestConfiguration(9F).


Contains the value read from the PC Card Configuration Register for a read operation. For a write operation, the Value field contains the value to write to the configuration register. As noted above, on return from a write request, the Value field is the value written to the PC Card and not any changed value that may have resulted from the write request (that is, no read after write is performed).

A client must be very careful when writing to the COR (Configuration Option Register) at offset 0. This has the potential to change the type of interrupt request generated by the PC Card or place the card in the reset state. Either request may have undefined results. The client should read the register to determine the appropriate setting for the interrupt mode (Bit 6) before writing to the register.

If a client wants to reset a PCCard, the csx_ResetFunction(9F) function should be used. Unlike csx_AccessConfigurationRegister(), the csx_ResetFunction(9F) function generates a series of event notifications to all clients using the PC Card, so they can re-establish the appropriate card state after the reset operation is complete.

Successful operation.


Specified arguments are invalid. Client specifies an Offset that is out of range or neither CONFIG_REG_READ or CONFIG_REG_WRITE is set.


Client has not called csx_RequestConfiguration(9F) before calling this function.


Client handle is invalid.


No PC card in socket.


No PCMCIA hardware installed.

This function may be called from user or kernel context.

csx_ParseTuple(9F), csx_RegisterClient(9F), csx_RequestConfiguration(9F), csx_ResetFunction(9F)

PCCard 95 Standard, PCMCIA/JEIDA

July 19, 1996 OmniOS