NAME
ieee1284_open - open a portSYNOPSIS
#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_EXCLThis 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_OKThe 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 <[email protected]>- Author.
COPYRIGHT
Copyright © 2001-2003 Tim Waugh| 09/18/2007 |