NAME
ieee1284_open - open a port
SYNOPSIS
#include <ieee1284.h>
int ieee1284_open(struct parport *port, int flags, int *capabilities);
DESCRIPTION
In order to begin using a port it must be opened. Any initial set-up of
the port is done at this stage. When an open port is no longer needed
it should be closed with ieee1284_close(3).
The possible flags are:
F1284_EXCL
This device cannot share the port with any other device. If this is
the case it must be declared at this stage, so that other drivers
trying to access the port know not to bother; otherwise they will
wait until this driver releases the port, i.e. never.
The iopl/dev-port access methods don’t support this yet, but the
ppdev ones do.
If capabilities is not NULL it must point to storage for an int, which
will be treated as a set of flags, one per bit, which the library sets
or clears as appropriate. If a capability is present it will be used
when asked for. They are:
CAP1284_RAW
Pin-level access is available. If this capability is present then
the following functions are effective: ieee1284_write_data,
ieee1284_read_status, ieee1284_wait_status, ieee1284_write_control,
ieee1284_read_control, ieee1284_frob_control.
CAP1284_NIBBLE
There is an implementation of nibble mode for this port.
CAP1284_BYTE
There is an implementation of byte mode for this port.
CAP1284_COMPAT
There is an implementation of compatibility mode for this port.
CAP1284_ECP
There is a hardware implementation of ECP mode for this port.
CAP1284_ECPRLE
There is an RLE-aware implementation of ECP mode for this port (the
F1284_RLE flag is recognised by the ECP transfer functions).
CAP1284_ECPSWE
There is a software implementation of ECP mode for this port.
CAP1284_BECP
There is an implementation of bounded ECP mode for this port.
CAP1284_EPP
There is a hardware implementation of EPP mode for this port.
CAP1284_EPPSWE
There is a software implementation of EPP mode for this port.
CAP1284_IRQ
An interrupt line is configured for this port and interrupt
notifications can be received using ieee1284_get_irq_fd(3).
CAP1284_DMA
A DMA channel is configured for this port.
RETURN VALUE
E1284_OK
The port is now opened.
E1284_INIT
There was a problem during port initialization. This could be
because another driver has opened the port exclusively, or some
other reason.
E1284_NOMEM
There is not enough memory.
E1284_NOTAVAIL
One or more of the supplied flags is not supported by this type of
port.
E1284_INVALIDPORT
The port parameter is invalid (for instance, the port may already
be open).
E1284_SYS
There was a problem at the operating system level. The global
variable errno has been set appropriately.
SEE ALSO
ieee1284_close(3)
AUTHOR
Tim Waugh <twaugh@redhat.com>
Author.
COPYRIGHT
Copyright © 2001-2003 Tim Waugh
09/18/2007