blog.crox.net

Using the HL-340 USB-serial adapter with Linux (1a86:7523, driver ch341)

nospam@example.com (crox) — Mon, 09 Jun 2008 13:07:03 +0200

Here is what dmesg reports :

New USB device found, idVendor=1a86, idProduct=7523
New USB device strings: Mfr=0, Product=2, SerialNumber=0
Product: USB2.0-Ser!

It works fine with the ch341 driver, I just had to add one line to drivers/usb/serial/ch341.c:

static struct usb_device_id id_table [] = {
        { USB_DEVICE(0x4348, 0x5523) },
        { USB_DEVICE(0x1a86, 0x7523) },
        { },
};

The relevant lines from my .config are:

CONFIG_USB_SERIAL=m
CONFIG_USB_SERIAL_GENERIC=y
CONFIG_USB_SERIAL_CH341=m

From the module comments:

ch341.c implements a serial port driver for the Winchiphead CH341.

The CH341 device can be used to implement an RS232 asynchronous serial port, an IEEE-1284 parallel printer port or a memory-like interface. In all cases the CH341 supports an I2C interface as well. This driver only supports the asynchronous serial interface.

I'm currently using a "vanilla" kernel 2.6.25.4.

Scanning barcodes with linux and a webcam

nospam@example.com (crox) — Sun, 11 May 2008 00:30:30 +0200

My Nokia phones can do it, so I thought there must be a way to do it on my laptop too. I wanted a way to scan both "traditional" barcodes and "two-dimensional" ones, like the QR-Codes. Here is my solution.

You'll need :

- a v4l-compatible webcam + mplayer compiled with v4l support (or any other scriptable way to grab frames from the webcam)

- a scriptable image viewer, I use feh on my laptop

- ZXing

Follow the instructions to build the ZXing javase component, then open three shell windows, and run:

shell1 (grab the webcam output as last.jpg +- every half second):

cd /tmp ; while [ 0 ] ; do mplayer tv:// -fps 2 -tv driver=v4l:width=640:height=480:device=/dev/video0 -vo jpeg:quality=95 -frames 2 ; mv 00000001.jpg last.jpg ; done

shell2 (view what you grabbed):

cd /tmp ; feh -R 1/2 last.jpg

shell3 (scan for barcodes):

while [ 0 ] ; do ( java -cp javase/javase.jar:core/core.jar com.google.zxing.client.j2se.CommandLineRunner /tmp/last.jpg | fgrep -v 'No barcode found') ; sleep 1 ; done

So no nice GUI, but it seems to work well.

Linux Kernel 2.6.25 on Gentoo sparc (error: -m64 is not supported by this configuration)

nospam@example.com (crox) — Fri, 25 Apr 2008 00:58:31 +0200

I wanted to try the new 2.6.25 kernel on a Sunblade 100 I'm reinstalling. But immediately after entering "make" I got the following error:

arch/sparc64/kernel/asm-offsets.c:1: error: -m64 is not supported by this configuration
arch/sparc64/kernel/asm-offsets.c:1: error: -mlong-double-64 not allowed with -m64
arch/sparc64/kernel/asm-offsets.c:1: error: -mcmodel= is not supported on 32 bit systems
make[1]: *** [arch/sparc64/kernel/asm-offsets.s] Error 1
make: *** [prepare0] Error 2

I found the solution here, along with the explanation. To make it short, to get it to work, for now you'll have to type:

 # CROSS_COMPILE=sparc64-unknown-linux-gnu- make

Linksys WAG200G-EU stops routing UDP after a while (scripted reboot how-to)

nospam@example.com (crox) — Fri, 07 Mar 2008 11:04:25 +0100

It seems that after having been up for a couple of days, the WAG200G starts having issues routing UDP packets properly. This particularly affects VoIP traffic (here IAX2 on port 4569). The symptoms are that "regular surfing" works flawlessly, but the registration with the asterisk server fails. tcpdump shows no traffic on the server side. Restarting the WAG200G immediately solves the problem.

Here is how I restarted the router from the command line:

wget --http-user=admin --http-password=pa55w0rd \
     --post-data='reboot=1&save=Enregistrer+les+param%E8tres&todo=reboot&h_reboot=1&this_file=Reboot.htm&next_file=index.htm&message=' \
     http://192.168.0.1/setup.cgi

(replace password and IP address as appropriate)

Diskless Ubuntu (Feisty Fawn NFS install)

nospam@example.com (crox) — Thu, 05 Jul 2007 22:23:16 +0200

Tonight I installed my first diskless Ubuntu system. The version I used is the latest available as of today, 7.04 "FeistyFawn". This article covers the client part.

My other diskless machines all run Gentoo (for the time being). I've described previously how I set up my SB 100, the rest of the setup was based on this article.

The following two articles were helpful:

https://help.ubuntu.com/community/Installation/OnNFSDrive
http://developer.novell.com/wiki/index.php/Feisty/HOWTO:_Convert_Ubuntu_to_Diskless

However I found some of the info to be uncomplete or outdated.

From what I have read, unlike with Gentoo, it seems that there is no easy way to get a working diskless Ubuntu system directly. Instead, you have to install to a disk first, and then make your setup diskless. I did not really want to open the box, so I tried first to install on a 2 GB CF card, which didn't work because the card was full before the install completed (du now reports that the system is 2.1 GB big). So I ended up putting a disk in the box, and I ran a regular install.

Note: As in the SB100 article, 10.0.0.10 will be my dhcp/nfs/tftp server ('fileserver'). 10.0.0.30 will be the Ubuntu desktop.

Once that was completed, instead of rebooting as suggested by the installer, I opened a shell (gnome-terminal), and ran:

sudo su -

mkdir /mnt/tmp

mkdir /mnt/nfs

mount /dev/sda1 /mnt/tmp

mount 10.0.0.10:/diskless/ubuntu /mnt/nfs

cp -a /mnt/tmp/* /mnt/nfs/

After that, there are just a couple of things that need to be changed:

chroot /mnt/nfs

mount -t proc proc proc

vi etc/initramfs-tools/initramfs.conf

and make sure you have:

BOOT=nfs

then run:

update-initramfs -u

Now check what you have in /boot, and update your network boot config files accordingly. I use pxegrub, and here is how /boot/grub.lst looks like:

default 0

timeout 10

title=Diskless Ubuntu

root (nd)

kernel /diskless/tv/boot/vmlinuz-2.6.20-15-generic ip=dhcp root=/dev/nfs nfsroot=10.0.0.10:/diskless/tv ro quiet splash

initrd /diskless/tv/boot/initrd.img-2.6.20-15-generic

Finally, don't forget to update etc/fstab and etc/network/interfaces. I've read several theories, here is what worked for me:

fstab:

# /etc/fstab: static file system information.

#

#                

proc            /proc           proc    defaults        0       0

/dev/nfs        /               nfs     defaults        0       0

/dev/scd0       /media/cdrom0   udf,iso9660 user,noauto     0       0

network/interfaces:

auto lo

iface lo inet loopback



auto eth0

iface eth0 inet static

        address 10.0.0.30

        netmask 255.255.255.0

        network 10.0.0.0

        broadcast 10.0.0.255

        gateway 10.0.0.1

(note: commenting out eth0 as suggested in some places made the system hang during the boot process.)

Lightning for x86_64 Linux (amd64)

nospam@example.com (crox) — Fri, 15 Jun 2007 16:50:29 +0200

Lightning is a Thunderbird plug-in that adds calendar functions. More on the mozilla.org page. I tried to install the .xpi from there, but it failed with the following error message:

"Lightning" could not be installed because it is not compatible with your Thunderbird build type (Linux_x86_64-gcc3). Please contact the author of this item about the problem.

So I downloaded the source from this page, and followed the instructions from here. This page and the link to that one were also helpful.

In case you don't want to open all those links, I've put the resulting .xpi file here for you to download: lightning-0.3.1-x86_64.xpi. Or if you prefer to build it yourself, here is how I did it:

[untar/bz, cd mozilla]
make distclean
export CFLAGS="-O2 -pipe -fPIC"
export CHOST="x86_64-pc-linux-gnu"
export CXXFLAGS="${CFLAGS}"
export MAKEOPTS="-j3"
ac_cv_visibility_pragma=no ./configure --enable-application=mail --enable-extensions=default,lightning
make

(of course you may want to change some stuff to better suit your system, I've got a Core 2 Duo laptop running Gentoo Linux)

Then just select Tools > Extensions in Thunderbird and install the lightning.xpi you've just built (located in dist/xpi-stage/lightning.xpi).

UPDATE - 2007-06-28 - Lightning 0.5

After reading Matthew's comment I downloaded the newly released Lightning 0.5 from here, and built lightning-0.5-x86_64.xpi following the exact same procedure that I used for 0.3.1. Then I installed it from Tools > Extensions, restarted Thunderbird and immediately noticed the different appearance. (I did not uninstall 0.3.1 first, which apparently is ok.)

Getting Google Earth for linux to work properly on amd64 (x86_64) Gentoo - i915 module (do_wait: drmWaitVBlank returned -1, IRQs don't seem to be working correctly. - Try running with LIBGL_THROTTLE_R

nospam@example.com (crox) — Sat, 02 Jun 2007 20:20:45 +0200

There is no 64 bit version of Google Earth for linux, so you'll need to make sure you have the latest version of the following packages first:

app-emulation/emul-linux-x86-baselibs
app-emulation/emul-linux-x86-compat
app-emulation/emul-linux-x86-gtklibs
app-emulation/emul-linux-x86-qtlibs
app-emulation/emul-linux-x86-soundlibs
app-emulation/emul-linux-x86-xlibs

This allowed me to start GE in the first place. But then it was horribly slow, although glxinfo reported "direct rendering: Yes" etc.

When started from the console, GE would output the following:

do_wait: drmWaitVBlank returned -1, IRQs don't seem to be working correctly.
Try running with LIBGL_THROTTLE_REFRESH and LIBL_SYNC_REFRESH unset.

Doing a search led me to try setting LIBGL_ALWAYS_INDIRECT=1 before running Google Earth. Indeed the warning disappeared, and GE was really faster. However, as soon as I would zoom too close, the whole screen was getting more and more sky-blue, until no image was being displayed anymore...

Finally, I found this article, and especially the comments from Eduardo Habkost and "Researcher".

I followed Researcher's instructions, and Google Earth is now working perfectly. For your convenience, I've put drm_nowaitVblank.c here to download (you cannot copy-paste from the original page because the parser there treats the includes as html code). Also to compile the code on amd64 you'll want to use gcc32 and not gcc...

Gentoo Linux on HP/Compaq nx7400 Core 2 Duo Laptop - Update (suspend to ram working now)

nospam@example.com (crox) — Tue, 08 May 2007 08:34:17 +0200

An update to my initial article on installing Gentoo on my nx7400 laptop:

I've switched to kernel 2.6.21-gentoo (latest gentoo-sources available currently with ~amd64), and to the latest versions of ipw3945, alsa and xorg, and suspend to ram works fine now. (the screen would not switch on again with vanilla kernel 2.6.19)

Hibernation (suspend to disk) seems to work as well, apart from the fact that the screen resolution is not restored correctly, but for now I'm happy with suspend-to-ram.

Convert Mac fonts to Unix / Windows format and vice-versa (dfont to ttf)

nospam@example.com (crox) — Fri, 27 Apr 2007 12:53:33 +0200

Fondu is "A set of programs to interconvert between mac font formats and pfb, ttf, otf and bdf files on unix."

I think that says it all :o) In particular, it allowed me to convert a .dfont-packaged font from a Mac to a set of .ttf files that I can use on my linux desktop.

How to set thunderbird to correctly attach text files (with Content-Disposition: attachment instead of inline)

nospam@example.com (crox) — Wed, 25 Apr 2007 10:32:47 +0200

For years I've been annoyed by the habit thunderbird has to set "Content-Disposition: inline" when you attach a text file to an outgoing e-mail.

Experimenting with our mail to fax gateway, I finally took the time to fix it today. As with some other "advanced" settings in Fireforx/Thunderbird, there is an option you can set to achieve the (imho) correct behavior, but no GUI dialog for it.

So in order to have outgoing text files attached with "Content-Disposition: attachment", you need to set mail.content_disposition_type to 1 (default is 0). You can do this by going to "Edit" -> "Preferences" -> "Advanced" -> "Config Editor". (Using the windows version it's probably "Tools" -> "Options" -> etc.)

Diskless Linux on a Sunblade 100

nospam@example.com (crox) — Sun, 01 Apr 2007 00:14:00 +0200

Initially written on 2006-05-17

On my other (x86/amd64) diskless machines, I use PXE with pxegrub. My setup is quite similar to (and inspired by) this one.

Now, on sparc machines, there is no BIOS nor PXE. But you don't need all that, since you have the Open Boot... This is how I managed to make my Sunblade 100 totally diskless (using a "vanilla" kernel, the latest version being currently 2.6.16.16).

Note: In this example, 10.0.0.10 will be my dhcp/nfs/tftp server which I will refer to as 'fileserver'. 10.0.0.30 is the sunblade.

- when configuring the kernel:

[*] Default bootloader kernel arguments (ip=dhcp root=/dev/nfs nfsroot=10.0.0.10:/diskless/sunblade)

(in "Networking" -> "Networking support" -> "Networking options")

[*]   IP: kernel level autoconfiguration
│ [*]     IP: DHCP support
│ [*]     IP: BOOTP support
│ [*]     IP: RARP support

(in "File systems" -> "Network File Systems")

<*> NFS file system support
[*]   Provide NFSv3 client support
[*] Root file system on NFS

Configure all other settings as you would do for a disk install, but make sure you compile your NIC driver in the kernel (not as module)

Then:

make
make modules_install
make tftpboot.img ROOT_IMG=/dev/null

(the resulting tftpboot.img will be in arch/sparc64/boot/tftpboot.img)

I copied tftpboot.img to fileserver as tftpimage-2.6.16.16, and added the following entry in my dhcpd.conf:

host sunblade {
    hardware ethernet 00:03:BA:08:12:34;
    fixed-address 10.0.0.30;
    always-reply-rfc1048 on;
    filename "sunblade/boot/tftpimage-2.6.16.16";
}

Finally, to net-boot your diskless Sunblade you'll need to enter

boot net:dhcp

in the Open Boot prompt. When you are happy with it, you can set it as default:

setenv boot-device net:dhcp cdrom disk net

Notes:

- apparently, instead of using make tftpboot.img you can just "elftoaout" vmlinux

- another alternative would be to use tilo, which comes with silo, to build the image

Gentoo sparc: sys-devel/kgcc64 vs. sys-devel/gcc-sparc64 (blocking each other)

nospam@example.com (crox) — Sun, 01 Apr 2007 00:09:00 +0200

If you get this:

[blocks B ] sys-devel/gcc-sparc64 (is blocking sys-devel/kgcc64-3.4.6)

Check this thread on the gentoo forums:

There are a couple of architectures on Gentoo that have a 32-bit userland, but need a 64-bit kernel compiler. kgcc64 is an attempt to provide one package for all of those architectures rather than the gcc- packages that exist now. The way we migrated over to this caused the issue you are seeing.

Basically, you'll need to

emerge --unmerge gcc-sparc64 && emerge sys-devel/kgcc64

Microsoft to pay companies to switch from Google to Live Search

nospam@example.com (crox) — Sat, 31 Mar 2007 23:36:38 +0200

see the following stories:

1. http://battellemedia.com/archives/003447.php

2. http://www.itwire.com.au/content/view/10554/532/

3. http://www.ledevoir.com/2007/03/19/135590.html (in French)

The first article describes the program. I also found most comments by the readers worth reading - and altogether they summarize pretty much everything I would have to say about it :o)

Zfone - secured VoIP conversations (SIP)

nospam@example.com (crox) — Sat, 31 Mar 2007 23:10:01 +0200

I came across this project the other day. Apparently it should work with any SIP-based VoIP client. (They list X-Lite, Gizmo and SJphone.)

I haven't had a chance to test it, but I sure will - they provide a source-form linux version. I may even contribute a gentoo e-build, since so far I couldn't find one...

What makes this project even more interesting to me is the fact that Phil Zimmermann, the original creator of PGP, is behind it.

TestDisk / PhotoRec: tool to recover lost files and partitions (Gentoo Linux)

nospam@example.com (crox) — Sun, 18 Mar 2007 22:55:00 +0100

Homepage: http://www.cgsecurity.org/

Description in portage: Multi-platform tool to check and undelete partition, supports reiserfs, ntfs, fat32, ext2/3 and many others. Also includes PhotoRec to recover pictures from digital camera memory.

Installation (Gentoo Linux amd64):

echo 'app-admin/testdisk ~amd64' >> /etc/portage/package.keywords
echo 'app-admin/testdisk jpeg ntfs' >> /etc/portage/package.use
emerge -av app-admin/testdisk

To use it, just run 'photorec' as root in a shell window. Despite the name, photorec will find and recover many files, not only pictures. You'll find the full list on the PhotoRec homepage.

I haven't tried TestDisk yet, but PhotoRec has been useful several times already.