From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Thomas Pfaff <tpfaff@pcs.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Question about TTY_DO_WRITE_WAKEUP
Date: Thu, 20 Nov 2008 13:17:26 +0000 [thread overview]
Message-ID: <20081120131726.2636b559@lxorguk.ukuu.org.uk> (raw)
In-Reply-To: <Pine.LNX.4.64.0811201007120.30713@lxtpfaff.pcs.ditec.de>
On Thu, 20 Nov 2008 11:06:19 +0100 (CET)
Thomas Pfaff <tpfaff@pcs.com> wrote:
> I have written a program that reads and writes data to the serial uart using
> async io.
> Unfortunately it does not work properly because a SIGIO is never gerated when
> output becomes possible, the reason is that TTY_DO_WRITE_WAKEUP is not set for
> most of the tty drivers. After i set the bit in serial_core.c the program works
> as expected.
> Now i wonder why TTY_DO_WRITE_WAKEUP is almost always disabled ?
Almost nobody uses SIGIO based I/O, especially on serial so I'm not
actually suprised by this one. If you've got patches that fix it then
please send them in.
Alan
next prev parent reply other threads:[~2008-11-20 13:18 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-11-20 10:06 Thomas Pfaff
2008-11-20 13:17 ` Alan Cox [this message]
2008-11-20 14:09 ` Thomas Pfaff
2008-11-20 14:31 ` Alan Cox
2008-11-20 15:12 ` Thomas Pfaff
2008-11-20 15:55 ` Alan Cox
2008-11-20 16:39 ` Thomas Pfaff
2008-11-20 16:47 ` Alan Cox
2008-11-20 16:58 ` Alan Cox
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20081120131726.2636b559@lxorguk.ukuu.org.uk \
--to=alan@lxorguk.ukuu.org.uk \
--cc=linux-kernel@vger.kernel.org \
--cc=tpfaff@pcs.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®