IBM Thinkpad T21: Hotplugging of cdrom and floppy devices

IBM Thinkpad T21: Hotplugging of cdrom and floppy devices

[Andreas Hartmann]

Hello all,

I'm using actual 2.4.x-kernels with the laptop I mentioned in the subject.

When I put off my floppy-device (/dev/fd1) and put in my cdrom-device 
(/dev/hdc; both no pcmcia-devices) or vice versa, the kernel doesn't 
recognize this change. The change - LED of the laptop is blinking until 
I suspend the laptop for example with apm -s or with the keyboard Fn-F4 
and rewake it. After this "little sleep", the kernel suddenly knows 
about the new hardware and it can handle it.

I tested the hotplugging-feature of the kernel 2.4.x - but I couldn't 
get it working.

Is there any other possibility to give the kernel a chance to detect a 
hardware change without going through the suspend-mode? I mean, is there 
a piece of software, which does the same as in the wake-up-situation of 
the notebook after suspend?

Thank you for your advice,
Andreas Hartmann

Re: IBM Thinkpad T21: Hotplugging of cdrom and floppy devices

[Colonel]

In clouddancer.list.kernel, <andihartmann@freenet.de> wrote:
>
>When I put off my floppy-device (/dev/fd1) and put in my cdrom-device 
>(/dev/hdc; both no pcmcia-devices) or vice versa, the kernel doesn't 
>recognize this change. The change - LED of the laptop is blinking until 
>I suspend the laptop for example with apm -s or with the keyboard Fn-F4 
>and rewake it. After this "little sleep", the kernel suddenly knows 
>about the new hardware and it can handle it.
>
>I tested the hotplugging-feature of the kernel 2.4.x - but I couldn't 
>get it working.
>
>Is there any other possibility to give the kernel a chance to detect a 
>hardware change without going through the suspend-mode? I mean, is there 
>a piece of software, which does the same as in the wake-up-situation of 
>the notebook after suspend?

The Thinkpad linux webpages mention : suspend, swap device, unsuspend.

I suspect there is a BIOS function that handles the device change,
since that is where the suspend actually occurs.  Windows must call it
directly.  Hotplugging is for the standard interfaces, the thinkpad
Ultrabay is unique.  You should probably be asking the IBM linux
group.

-- 
Windows 2001: "I'm sorry Dave ...  I'm afraid I can't do that."

Re: IBM Thinkpad T21: Hotplugging of cdrom and floppy devices

[Alan Cox]

> I suspect there is a BIOS function that handles the device change,
> since that is where the suspend actually occurs.  Windows must call it
> directly.  Hotplugging is for the standard interfaces, the thinkpad
> Ultrabay is unique.  You should probably be asking the IBM linux
> group.

My first guess would be that you want to look at the PNPBIOS support from
the -ac tree and see if you get PNPBIOS events.