From: Grant Edwards <grant.b.edwards@gmail.com>
To: linux-serial@vger.kernel.org
Subject: Re: New serial card development
Date: Tue, 23 Oct 2012 18:45:51 +0000 (UTC) [thread overview]
Message-ID: <k66okv$811$1@ger.gmane.org> (raw)
In-Reply-To: 20121023192633.18849645@pyramind.ukuu.org.uk
On 2012-10-23, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
>> Can it be guaranteed that it's going to be fast enough at high
>> baud-rates to prevent any gap between the first byte and subsequent
>> bytes?
>
> Possibly not for some protocols (or worse yet 'almost always' for
> some protocols).
>
> It's something to look at once the basic bits are in.
>
>> I now work for a company that has manufactured PC serial boards for
>> 25+ years, and we still get regular requests for that feature (and our
>> boards do support it -- though our Linux driver does not).
>
> In which case when we get to addressing this it will be good to make
> sure we cover your needs as well.
FWIW, in some products we're planning that will require support for
various industrial serial protocols, I'm leaning towards abandoning
the tty driver approach and writing a stand-alone character device
driver. The byte-stream oriented tty/line-discipline layer just
doesn't fit well when dealing with frame-oriented industrial protocols
that depend on things like 9th bit addressing and detecting
sub-millisecond inter-byte timeouts. When I add in the lack of
long-term stability in the tty API it seems like it might not be such
a bad idea to give up trying to make the tty abstraction fit a use
case that's just nothing like a teletype.
--
Grant Edwards grant.b.edwards Yow! Gibble, Gobble, we
at ACCEPT YOU ...
gmail.com
next prev parent reply other threads:[~2012-10-23 18:46 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-10-09 18:43 New serial card development Matt Schulte
2012-10-14 9:37 ` Theodore Ts'o
2012-10-15 19:08 ` Matt Schulte
2012-10-15 23:26 ` Alan Cox
2012-10-16 2:32 ` Theodore Ts'o
2012-10-17 20:24 ` Matt Schulte
2012-10-19 21:21 ` Theodore Ts'o
2012-10-23 16:27 ` Matt Schulte
2012-10-23 16:31 ` Matt Schulte
2012-10-23 18:38 ` Greg KH
2012-10-29 20:04 ` Matt Schulte
2012-10-31 21:55 ` Matt Schulte
2012-11-01 22:03 ` Matt Schulte
2012-11-01 22:26 ` Alan Cox
2012-11-02 18:47 ` Matt Schulte
2012-11-02 20:21 ` Alan Cox
2012-10-23 18:06 ` Grant Edwards
2012-10-23 18:26 ` Alan Cox
2012-10-23 18:45 ` Grant Edwards [this message]
2012-10-23 19:16 ` Greg KH
2012-10-23 19:42 ` Grant Edwards
2012-10-23 20:10 ` Greg KH
2012-10-23 19:24 ` Alan Cox
2012-10-23 19:48 ` Grant Edwards
2012-10-23 20:31 ` Theodore Ts'o
2012-10-23 20:41 ` Grant Edwards
[not found] ` <CAJp1Oe6k7NWqdbYkJnd787JiT55-wSbG+tX1tP7Cy-oPShdVaA@mail.gmail.com>
2012-10-17 20:23 ` Matt Schulte
2012-10-17 21:53 ` 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='k66okv$811$1@ger.gmane.org' \
--to=grant.b.edwards@gmail.com \
--cc=linux-serial@vger.kernel.org \
/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;
as well as URLs for NNTP newsgroup(s).