From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by befuddled.reisers.ca (Postfix, from userid 65534) id 19D4C1EF69C; Thu, 26 Jun 2014 18:06:14 -0400 (EDT) Received: from mail0131.smtp25.com (mail0131.smtp25.com [75.126.84.131]) by befuddled.reisers.ca (Postfix) with ESMTPS id 2D8DD1EF516 for ; Thu, 26 Jun 2014 18:06:11 -0400 (EDT) Received: from ccs.covici.com (s-out-001.smtp25.com [67.228.91.90]) by d-out-001.smtp25.com (8.14.2/8.14.2) with ESMTP id s5QM60kR004041 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL) for ; Thu, 26 Jun 2014 18:06:01 -0400 Received: from ccs.covici.com (localhost [127.0.0.1]) by ccs.covici.com (8.14.8/8.14.8) with ESMTP id s5QM5xSa029534 for ; Thu, 26 Jun 2014 18:05:59 -0400 To: "Speakup is a screen review system for Linux." Subject: Re: slackware on a very fast machine In-reply-to: <53AC9533.3010906@math.wisc.edu> References: <53AC736D.3050405@math.wisc.edu> <53AC9533.3010906@math.wisc.edu> Comments: In-reply-to "John G. Heim" message dated "Thu, 26 Jun 2014 16:48:35 -0500." X-Mailer: MH-E 8.2; nmh 1.3; GNU Emacs 23.4.1 Date: Thu, 26 Jun 2014 18:05:59 -0400 Message-ID: <29532.1403820359@ccs.covici.com> From: covici@ccs.covici.com X-SpamH-OriginatingIP: 70.109.53.110 X-SpamH-Filter: d-out-001.smtp25.com-s5QM60kR004041 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 X-BeenThere: speakup@linux-speakup.org X-Mailman-Version: 2.1.16 Precedence: list Reply-To: "Speakup is a screen review system for Linux." List-Id: "Speakup is a screen review system for Linux." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 26 Jun 2014 22:06:14 -0000 Well, the serial console code in the kernel does write directly to the port, but it seems to be only working during the early boot -- I should look at this again, this is how I wrote the first serial driver for speakup -- coping the serial code, but at the time speakup was not part of the kernel, in order to be part of the kernel, things had to change a lot. John G. Heim wrote: > > > The serial consoles you are talking about run in what's called user > space. When you connect to a serial console, you're actually talking > to a server process called getty or agetty. It's not that different > from a web server or ssh server. The kernel doesn't know or care about > those processes. Accessing the serial port in a kernel module is a > totally different process. > > Of course, you may be saying, "Ah, but I can set up a serial console > in the kernel". And this is correct. But that console stops working > once the kernel is booted and if you want to continue to use a console > on that same serial port you have to set up a getty. If you have a > terminal or terminal emulator listening on ttyS0, it may appear to be > seamless but it's actually switching from kernel output to a getty. > > So now maybe you are asking why can't speakup just access the serial > port the same way as the kernel serial console? And that I don't > know. I suspect that code doesn't do things the "right way" > either. The speakup code talks directly to the serial port at address > 3F8. you're not supposed to do that. First it calls a function that is > part of the regular kernel code that appears to do nothing except > return an error code. Upon getting that error code, the speakup code > errors out. All you have to do to make it work is comment out the part > where the speakup code errors out. But my patch removes the call to > the stupid/crazy function as well. > > That function cannot return a success, so why call it? It's crazy. It > makes no sense what so ever. I've asked twice on the kernel mailing > list what the speakup code should do instead and got nothing but > static. All the answers I got either made no sense or they suggested > rewriting the speakup code so that it would run in user space. But > that would make it practically useless. The beauty of speakup is that > you can get boot messages with it. > > I was so angry at one point I considered contacting a lawyer. What I > really should do is find out how the kernel serial console does > it. I'll bet it reads/writes directly to 0x3F8 as well. In that case, > the linux kernel developers are discriminating against speakup. > > The problem doesn't really even effect me that much. I can easily just > recompile the kernel. I've got my version of the debian wheezy kernel > on about 200 amachines here in my department. But if I have to use > grml, I can't use my litetalk. > > > > > On 06/26/14 15:02, Rob Hudson wrote: > > I don't understand why the kernel has serial bugs. Many many many > > companies still use serial consoles, and in fact, as faras I know, it is > > still the most common way of interacting directly with rack-mounted > > computers and some high end routers. What's the deal? > > ----- Original Message ----- From: "John G. Heim" > > To: "Speakup is a screen review system for Linux." > > > > Sent: Thursday, June 26, 2014 2:24 PM > > Subject: Re: slackware on a very fast machine > > > > > >> The syntax is "modprobe speakup_ltlk". > >> > >> But it isn't going to help unless slackware hacked the kernel clode > >> to fix the serial port bug. If they used the speakup code as it is in > >> the kernel, your litetalk won't work. > >> I started trying to make a fork of grml with a patched kernel but > >> never had the time to really get into it. Instead I've been using an > >> FAI disk. FAI is actually an installer system. FAI stands for fully > >> automated install. But they make it real easy to create a live CD. > >> On 06/26/14 14:12, Jude DaShiell wrote: > >>> I can't determine when the 10 seconds starts or ends with > >>> slackware-Current on this machine since the machine appears to be > >>> running > >>> too fast to get any usable audible indicators from it any longer. > >>> What is > >>> the correct syntax to modprobe speakup and have speakup come up on a > >>> litetalk synthesizer on ttyS0? I might be able to get slackware to run > >>> the speakup.s kernel and if I can do that, I ought to be able to key the > >>> modprobe line in once I get in as root. > >>> > >>> > >>> > >>> jude > >>> > >>> _______________________________________________ > >>> Speakup mailing list > >>> Speakup@linux-speakup.org > >>> http://linux-speakup.org/cgi-bin/mailman/listinfo/speakup > >>> > >> > >> -- > >> --- > >> John G. Heim, 608-263-4189, jheim@math.wisc.edu > >> _______________________________________________ > >> Speakup mailing list > >> Speakup@linux-speakup.org > >> http://linux-speakup.org/cgi-bin/mailman/listinfo/speakup > >> > > > > _______________________________________________ > > Speakup mailing list > > Speakup@linux-speakup.org > > http://linux-speakup.org/cgi-bin/mailman/listinfo/speakup > > -- > --- > John G. Heim, 608-263-4189, jheim@math.wisc.edu > _______________________________________________ > Speakup mailing list > Speakup@linux-speakup.org > http://linux-speakup.org/cgi-bin/mailman/listinfo/speakup -- Your life is like a penny. You're going to lose it. The question is: How do you spend it? John Covici covici@ccs.covici.com