Writing Device Drivers

Header Files

Header files define data structures specific to the device (such as a structure representing the device registers), data structures defined by the driver for maintaining state information, defined constants (such as those representing the bits of the device registers), and macros (such as those defining the static mapping between the minor device number and the instance number).

Some of this information, such as the state structure, may only be needed by the device driver. This information should go in private headers. These header files are included only by the device driver itself.

Any information that an application might require, such as the I/O control commands, should be in public header files. These are included by the driver and any applications that need information about the device.

There is no standard for naming private and public files. One possible convention is to name the private header file xximpl.h and the public header file xxio.h.

Source Files

A.c file for a device driver contains the data declarations and the code for the entry points of the driver. It contains the #include statements the driver needs, declares extern references, declares local data, sets up the cb_ops and dev_ops structures, declares and initializes the module configuration section, makes any other necessary declarations, and defines the driver entry points.

Configuration Files

Information for configuration files used with device drivers can be found in driver.conf(4), sbus(4), pci(4), and isa(4).


2. Overview of Solaris Device Drivers Device Driver Design Considerations Driver Layout


	Header Files Header files define data structures specific to the device (such as a structure representing the device registers), data structures defined by the driver for maintaining state information, defined constants (such as those representing the bits of the device registers), and macros (such as those defining the static mapping between the minor device number and the instance number). Some of this information, such as the state structure, may only be needed by the device driver. This information should go in private headers. These header files are included only by the device driver itself. Any information that an application might require, such as the I/O control commands, should be in public header files. These are included by the driver and any applications that need information about the device. There is no standard for naming private and public files. One possible convention is to name the private header file `xximpl.h` and the public header file `xxio.h`. Source Files A`.c` file for a device driver contains the data declarations and the code for the entry points of the driver. It contains the #include statements the driver needs, declares extern references, declares local data, sets up the `cb_ops` and `dev_ops` structures, declares and initializes the module configuration section, makes any other necessary declarations, and defines the driver entry points. Configuration Files Information for configuration files used with device drivers can be found in `driver.conf`(4), `sbus`(4), `pci`(4), and `isa`(4).