public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: "Shaun Jackman" <sjackman@gmail.com>
To: LKML <linux-kernel@vger.kernel.org>
Subject: TL16C752B DUART: MCR_OUT2 disables interrupts
Date: Tue, 20 Jun 2006 14:07:36 -0600	[thread overview]
Message-ID: <7f45d9390606201307yfdb8aadn4d00a6afeba0b09b@mail.gmail.com> (raw)

The datasheet I have for the TL16C752B labels the MCR_OUT1 bit as
`FIFO Rdy enable' and the MCR_OUT2 bit as `IRQ enable'. The latter bit
concerns me. The 8250.c driver sets MCR_OUT2 by default; however, if
the user space clears MCR_OUT2 (through an ioctl TIOCMSET operation or
similar), it seems to me that interrupts for that UART will stop
working. Can someone confirm my suspicion?

I'd expect that clearing/setting the OUT1 and OUT2 pins from user
space should be an innocuous operation. Disabling interrupts is a
fairly nasty side effect.

Please cc me in your reply. Cheers,
Shaun

             reply	other threads:[~2006-06-20 20:07 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-06-20 20:07 Shaun Jackman [this message]
2006-06-20 20:26 ` TL16C752B DUART: MCR_OUT2 disables interrupts Paul Fulghum
2006-06-20 20:35   ` Shaun Jackman
2006-06-20 20:37     ` Paul Fulghum

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=7f45d9390606201307yfdb8aadn4d00a6afeba0b09b@mail.gmail.com \
    --to=sjackman@gmail.com \
    --cc=linux-kernel@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