BSP Developer's Guide

H
Implementing a MUX-Based Network Interface Driver
This function should return OK or ERROR. If an error occurs, it should set errno.
The parameters are:
pCookie
Passes in a pointer to the END_OBJ structure returned by endLoad( ).
Handling a Polling Send: endPollSend( )
Your endPollSend( ) is used by any task (such as the debug agent) that wants to
do a polling send. Thus, your endPollSend( ) must be able to put a packet directly
onto the network stack without queuing a packet on an output queue.
NOTE: When the system calls your endPollSend( ), it is probably in a mode that
cannot service kernel calls. Thus, this entry point should not call any kernel
functions, such as taking a semaphore or allocating memory. Likewise, this entry
point should not block or busy wait because that would probably hang the entire
system.
Your endPollSend( ) must take the following form:
STATUS endPollSend
(
void* pCookie, /* device structure */
M_BLK_ID pMblk, /* data to send */
)
Within your endPollSend( ), check that the device is set to polled mode (by a
previous endIoctl( ) call). Your endPollSend( ) should then put the packet (passed
using pNBuff) directly onto the network. Your endPollSend( ) bypasses queuing
the packet on any output queue.
This function should return OK or ERROR. If an error occurs, it should set errno.
The parameters are:
pCookie
Passes a pointer to the END_OBJ structure returned by endLoad( ).
pMblk
Passes a pointer to an mBlk structure containing the data you want to send.
For information on setting up an mBlk, see H.3.1 Setting Up and Using a
Memory Pool for Receive and Transmit Buffers, p.276.
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