The following code shows the declarations of the timeout and interrupt
information in the
if_el
device driver’s
el_softc
data structure:
unsigned long
txreset;
1
unsigned long
xmit_tmo;
2
unsigned long
tint;
3
unsigned long
rint;
4
1
Contains the number of transmitter error resets.
2
Contains the number of times that transmit timeouts occurred. The
el_watch( )
routine increments this member.
3
Contains the count of transmit interrupts.
4
Contains the count of receive interrupts.
3.13 Defining Autosense Kernel Thread Context Information
The autosense kernel thread context information in the
if_el
driver’s
el_softc
data structure consists of information about the kernel thread
that performs the autosense operation. For the
if_el
driver, this kernel
thread is called
el_autosense_thread
.
The following code shows the declarations of the autosense kernel thread
variables in the
if_el
device driver’s
el_softc
data structure. The
if_el
device driver uses kernel threads to perform the tasks that are related to
autosensing the media. However, you can choose other methods instead of
kernel threads.
thread_t
autosense_thread;
1
int
autosense_flag;
2
1
Contains the autosense kernel thread ID.
2
Contains the autosense kernel thread blocking flag.
3.14 Defining the Polling Context Flag
A LAN driver typically does not need to perform polling operations. However,
the
if_el
driver provides an example of how polling operations might be
accomplished.
The polling context flag in a network driver’s
softc
data structure indicates
whether polling is on or off. The following code shows the declaration of the
polling member in the
if_el
device driver’s
el_softc
data structure:
int
polling_flag;
1
1
Declares a polling context flag member called
polling_flag
. This
member stores a boolean value of 1 (polling context is on) or 0 (polling
context is off).
Defining the softc Data Structure 3–9
