Regression from Gutsy: Samsung SCX4200 does not work on Hardy

[Tayroni Alves]

Summary: I have installed the samsung unified driver in Gutsy and on Hardy. The scanner works on gutsy but not on Hardy (libsane 1.0.19-1ubuntu3).

Description: I've installed the driver provided by samsung. The scanner works on a clean install of Gutsy. The same don't happen for Hardy: the scanner is not recognized by xsane.

Output of sane-find-scanner (both Gutsy and Hardy).

found USB scanner (vendor=0x04e8 [Samsung], product=0x341b [SCX-4200 Series]) at libusb:002:003

Using sudo scanimage -L, the scanner is found on gutsy, but not on hardy.

[Tayroni Alves (tay-fisica)]

Fell free to mark this as fixed.

The problem is that the closed source driver software by samsung looks for the usb device on

/proc/bus/usb/00*/00*

and AFAIK 8.04 drops support to /proc/bus/usb/00*/00* and port all software to see the usb devices only on /dev/bus/usb/00*/00*

To reenable support on /proc/bus/usb I edited /etc/init.d/mountdevsubfs.sh

and I modified the lines

#
# Magic to make /proc/bus/usb work
#
#mkdir -p /dev/bus/usb/.usbfs
#domount usbfs "" /dev/bus/usb/.usbfs -obusmode=0700,devmode=0600,listmode=0644
#ln -s .usbfs/devices /dev/bus/usb/devices
#mount --rbind /dev/bus/usb /proc/bus/usb

to

#
# Magic to make /proc/bus/usb work
#
mkdir -p /dev/bus/usb/.usbfs
domount usbfs "" /dev/bus/usb/.usbfs -obusmode=0700,devmode=0600,listmode=0644
ln -s .usbfs/devices /dev/bus/usb/devices
mount --rbind /dev/bus/usb /proc/bus/usb

and reboot. After that, the scanner works like a charm on Hardy Heron.

[Marcelo Fernandez (fernandezm)]

I can confirm this workaround in my Hardy AMD64 desktop. But I hope Samsung can package better drivers for this device.

[Sokolov Sergey (cleversokol-deactivatedaccount)]

There the problem I reported in Bug #303145 but it was marked as duplikate. In 8.04.1 or 8.10 or newer Ubuntu in /etc/init.d/mountdevsubfs.sh there are no such lines. You can see the file in the attachment.

And why this scanner works fine with other Linux distributives?

[Duck (duckjcv)]

SCX4200 en ubuntu 8.10 OK OK OK

Después de instalar la impresora con el driver oficial de Samsung, y comprobar que la impresora funciona bien, falta detectar el scaner. Para eso:

sudo adduser your_login_here lp
sudo adduser your_login_here lpadmin
sudo adduser your_login_here scanner

and edit the file /etc/init.d/mountdevsubfs.sh. ADD THE LINES:

#
# Magic to KEEP /proc/bus/usb working
#
mkdir -p /dev/bus/usb/.usbfs
domount usbfs "" /dev/bus/usb/.usbfs usbfs -obusmode=0700,devmode=0600,listmode=0644
ln -s .usbfs/devices /dev/bus/usb/devices
mount --rbind /dev/bus/usb /proc/bus/usb

right below the line

domount devpts "" /dev/pts devpts -onoexec,nosuid,gid=$TTYGRP,mode=$TTYMODE

Finally, REBOOT!!

(en http://ge.ubuntuforums.com/showthread.php?s=6db0e4ad1558703bc1665ff4059c1d50&t=762159&page=2)