adapter/parport: Deprecate direct I/O support

We deprecate direct I/O support in favor of ppdev for the following
reasons:

  - Linux supports ppdev since ~2.4 (released ~24 years ago) and it is
    enabled by default on major distros (Ubuntu, Fedora). So it is
    effectively ubiquitous
  - FreeBSD provides no direct I/O support, so ppdev (ppi) is the only
    viable option
  - Direct I/O requires root/elevated privileges which is inadvisable
  - Removing direct I/O reduces build and driver complexity and yields
    a smaller, easier-to-maintain codebase
  - Supporting only ppdev allows us to simplify the codebase by using
    device files (e.g., /dev/parport0) instead of numeric identifiers

Windows is the only rationale to keep direct I/O, but the user base
appears minimal to nonexistent and no active contributors can test the
Windows driver.

Change-Id: Ia6d5ed6e8c5faa2a9b4919ca97c5cf9033372a64
Signed-off-by: Marc Schink <dev@zapb.de>
Reviewed-on: https://review.openocd.org/c/openocd/+/9151
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>
Tested-by: jenkins
This commit is contained in:
Marc Schink
2025-08-17 14:11:39 +00:00
committed by Antonio Borneo
parent 6d51e6b900
commit 39ed0b0bba
3 changed files with 10 additions and 1 deletions

View File

@@ -3225,6 +3225,7 @@ The default port number is 0.
When using direct I/O, the number is the I/O port number.
The default port number is 0x378 (LTP1).
@b{Note:} Direct I/O support is deprecated and will be removed in the future.
@end deffn
@deffn {Config Command} {parport write_on_exit} (@option{on}|@option{off})