RedHat sees and uses modem with nousb, but Knoppix fails

[rpeck]

Does "nousb" really work?

I've been trying to get a USR 5610 hardware hardware modem working, as can be seen in another thread in the Networking forum. I now believe that the problem is an irq/boot-time problem, so I've moved over here.

On this box, XP reports that the modem and the USB controller both use irq 23. XP is able to use the modem just fine.

I installed RedHat (don't know which version, but I just bought it at Fry's a couple weeks ago so it's pretty recent). RedHat's modem config wizard found the modem just fine, and lspci showed it using irq 5 (NOTE: not 23). When booting with default options, RedHat will hang when setting up the USB controller. If I give the "nousb" boot option, I can boot RedHat, and the modem works (I can get a PPP connection). I wrote down the output of setserial -G so I could reproduce the config in Knoppix.

On my Knoppix HD install, I booted with nousb, did the setserial command that I got from RedHat, linked /dev/modem to the device file (which happens to be /dev/ttyS4). No dice: kppp and wvdialconf still don't detect the modem.

I also tried disabling USB in the bios setup. The irq reported by lspci -v moved from 5 to 6. I changed my setserial command accordingly, but no dice. I also tried booting with nopcmcia noscsi alongside nousb, with the same result.


Any clues?

[wh7qq]

The dmesg output from various flavors of linux using 2.6.x shows a reference to the effect that "pci irq's are no longer automatically assigned". I also found the following reference that shows that this has been changed in the 2.6.x kernels:

Subject Re: [PATCH] PCI fixes for 2.6.10-rc1
Date Fri, 12 Nov 2004 15:21:55 -0800
From Greg KH <>
ChangeSet 1.2026.35.4, 2004/10/28 15:56:14-05:00, akpm@osdl.org
[PATCH] PCI: remove unconditional PCI ACPI IRQ routing
From: Bjorn Helgaas <bjorn.helgaas@hp.com>
Now that PCI interrupts are routed in pci_enable_device(), remove the
unconditional routing previously done in pci_acpi_init().
This has the potential to break drivers that don't use pci_enable_device()
correctly, so I also added a "pci=routeirq" kernel option that restores the
previous behavior. I intend to remove that option, along with all the code
below, in a month or so.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

So if someone can tell me how to incorporate the "pci=routeirq" line in the init sequence or how to use "pci_enable_device" we might be able to solve this problem that has (with obvious malice aforethought) messed up a lot of folks. :wink:

[rwcitek]

So if someone can tell me how to incorporate the "pci=routeirq" line in the init sequence or how to use "pci_enable_device" we might be able to solve this problem that has (with obvious malice aforethought) messed up a lot of folks. :wink:
You should be able to type that at the boot prompt: boot: knoppix pci=routeirq

This was taken from the kernel-parameters.txt file on another Linux machine running the 2.6.x kernel.

Let us know if that works for you.

Regards,
- Robert
http://www.cwelug.org/

[tdjokic]

This is one site:
http://www.math.sunysb.edu/~comech/tools/PCImodems.html

This is another:
"The 5610B works with Mepis 2004.06 and SM 3.3. I did nothing special. But you have to make sure you have it on the correct COM Port for your machine. Sometimes u have to confirm the com port via windoz - I hate to say that. You may have to link the port to /dev/modem.

Alternatively, try ls -l /dev/modem to find out the com port. You can also do things like ls -l /dev/ttyS2, etc. All from Command line. The latter gives the c 4 68 part of it. Also see man pages on ls. Watch the spaces in the code.

Two other handy pieces of code, from cmnd line as su:

mknod /devttyS2 c 4 68 Here S2 is COM3, etc.
(this sets S2)

ln -s /dev/ttyS2 /dev/modem Links e.g. S2 to /dev/modem"

[wh7qq]

Very interesting! It work (3.8.1 Live) if I use the boot prompt knoppix pci=routeirq and then do sudo setserial /dev/ttyS4 port 0x9000 irq 16 uart 16550 auto_irq skip_test autoconfig spd_vhi (parameters found with lspci -vv). KPPP will then find the modem when you do a modem querry and connects just fine.

In trying to port this to an HD installation of Kanotix 2005-02, adding the pci=routeirq into the boot parameters does not work. KPPPstill reports "Modem Busy" as before. I haven't been able to find "kernel-parameters.txt" anywhere.

This is progress and confirms the culprit...thanks!

How to get this into the HD boot?

Paul

[rwcitek]

Very interesting! It work (3.8.1 Live)
Woo-hoo! Break out the champaign.


I haven't been able to find "kernel-parameters.txt" anywhere.
You've got a HD install of Kanotix? If so, then 'apt-get update && apt-get install kernel-doc-2.6*'. Then look in /usr/share/doc/kernel-doc-2.6.*/Documentation/kernel-parameters.txt.gz


How to get this into the HD boot?
Can you post your modified configuration file for the bootloader (IIRC, Kanotix uses grub.conf)?

Regards,
- Robert
http://www.cwelug.org/

[wh7qq]

I haven't been able to find "kernel-parameters.txt" anywhere.
You've got a HD install of Kanotix? If so, then 'apt-get update && apt-get install kernel-doc-2.6*'. Then look in /usr/share/doc/kernel-doc-2.6.*/Documentation/kernel-parameters.txt.gz

]No file or directory called kernel-doc anything even after" apt-get update" and "apt-get update && apt-get install kernel-doc-2.6"[/b][/b]


How to get this into the HD boot?
Can you post your modified configuration file for the bootloader (IIRC, Kanotix uses grub.conf)?
No grub.conf or anything close found in search on "*grub*" in /. Very strange this Kanotix.



Regards,
- Robert
http://www.cwelug.org/[/quote]N