[Qemu-devel] qemu: hardware error: Failed to create USB device 'usb-tablet'

[Qemu-devel] qemu: hardware error: Failed to create USB device 'usb-tablet'

[dpc]

Hi,

I'm trying to get the tablet emulation for Qemu's VNC server to handle
the mouse better. I'm using `qemu-system-arm` and everything is OK
except for the mouse movement.

After I add `-usb -usbdevie table` argument to `qemu-system-arm`
invocation I get:

qemu: hardware error: Failed to create USB device 'usb-tablet'

CPU #0:
R00=00000000 R01=00000000 R02=00000000 R03=00000000
R04=00000000 R05=00000000 R06=00000000 R07=00000000
R08=00000000 R09=00000000 R10=00000000 R11=00000000
R12=00000000 R13=00000000 R14=00000000 R15=00000000
PSR=400001d3 -Z-- A svc32
Aborted


right after starting qemu.

Any idea why is this happening or is this even possible? I has been
googling for this, but with no success.

Regards,
-- 
Dawid Ciężarkiewicz

Re: [Qemu-devel] qemu: hardware error: Failed to create USB device 'usb-tablet'

[Peter Maydell]

On 29 June 2011 14:21, dpc@ucore.info <dpc@ucore.info> wrote:
> I'm trying to get the tablet emulation for Qemu's VNC server to handle
> the mouse better. I'm using `qemu-system-arm` and everything is OK
> except for the mouse movement.
>
> After I add `-usb -usbdevie table` argument to `qemu-system-arm`
> invocation I get:
>
> qemu: hardware error: Failed to create USB device 'usb-tablet'

Which machine are you using? The default (integratorcp) does not
have a USB controller modelled, so there's nothing to plug the
tablet into and QEMU fails with the above slightly cryptic message...
Try "-M versatilepb".

-- PMM

Re: [Qemu-devel] qemu: hardware error: Failed to create USB device 'usb-tablet'

[dpc]

On Wed, Jun 29, 2011 at 4:52 PM, Peter Maydell <peter.maydell@linaro.org> wrote:
> Which machine are you using? The default (integratorcp) does not
> have a USB controller modelled, so there's nothing to plug the
> tablet into and QEMU fails with the above slightly cryptic message...
> Try "-M versatilepb".

Hmmm. I'm using `vexpress-a9` and it's important for me not to change
it. Should it work for this board? It's the latest supported board
AFAIK.

Thanks for clarification.

Regards,
-- 
Dawid Ciężarkiewicz

Re: [Qemu-devel] qemu: hardware error: Failed to create USB device 'usb-tablet'

[Peter Maydell]

On 29 June 2011 18:08, dpc@ucore.info <dpc@ucore.info> wrote:
> On Wed, Jun 29, 2011 at 4:52 PM, Peter Maydell <peter.maydell@linaro.org> wrote:
>> Which machine are you using? The default (integratorcp) does not
>> have a USB controller modelled, so there's nothing to plug the
>> tablet into and QEMU fails with the above slightly cryptic message...
>> Try "-M versatilepb".
>
> Hmmm. I'm using `vexpress-a9` and it's important for me not to change
> it. Should it work for this board? It's the latest supported board
> AFAIK.

Unfortunately there isn't a QEMU model of the ISP1761 USB controller
which the Versatile Express uses, so that machine model doesn't have
USB support. (versatilepb gets USB support via its PCI bus, but
there is no PCI for vexpress.)

-- PMM

Re: [Qemu-devel] qemu: hardware error: Failed to create USB device 'usb-tablet'

[dpc]

On Wed, Jun 29, 2011 at 7:25 PM, Peter Maydell <peter.maydell@linaro.org> wrote:
> Unfortunately there isn't a QEMU model of the ISP1761 USB controller
> which the Versatile Express uses, so that machine model doesn't have
> USB support. (versatilepb gets USB support via its PCI bus, but
> there is no PCI for vexpress.)
>

Are you aware when can this be supported? I'm aware that Linaro's Qemu
had something about it in TODO for their next release.

Also,

Are you aware what is the root of the problem of Qemu not being able
to emulated correct pointer position with mouse device in VNC mode and
requiring tablet? I'm aware of tablet vs mouse difference in specifing
the coordinates (absolute vs relative). I'm just not aware why Qemu
can't translate one into other correctly? I guess I must be missing
something if this haven't been yet fixed.

-- 
Dawid Ciężarkiewicz

Re: [Qemu-devel] qemu: hardware error: Failed to create USB device 'usb-tablet'

[Peter Maydell]

On 30 June 2011 08:20, dpc@ucore.info <dpc@ucore.info> wrote:
> On Wed, Jun 29, 2011 at 7:25 PM, Peter Maydell <peter.maydell@linaro.org> wrote:
>> Unfortunately there isn't a QEMU model of the ISP1761 USB controller
>> which the Versatile Express uses, so that machine model doesn't have
>> USB support. (versatilepb gets USB support via its PCI bus, but
>> there is no PCI for vexpress.)

> Are you aware when can this be supported? I'm aware that Linaro's Qemu
> had something about it in TODO for their next release.

You're probably thinking of the USB support in the OMAP3 beagle/overo
models in qemu-linaro: different chip. I don't have any plans for
vexpress USB support, I'm afraid. (We only have limited resources for
qemu work and for most purposes the standard ps2 mouse works fine on
vexpress.)

-- PMM

Re: [Qemu-devel] qemu: hardware error: Failed to create USB device 'usb-tablet'

[Alexander Graf]

On 30.06.2011, at 09:20, dpc@ucore.info wrote:

> On Wed, Jun 29, 2011 at 7:25 PM, Peter Maydell <peter.maydell@linaro.org> wrote:
>> Unfortunately there isn't a QEMU model of the ISP1761 USB controller
>> which the Versatile Express uses, so that machine model doesn't have
>> USB support. (versatilepb gets USB support via its PCI bus, but
>> there is no PCI for vexpress.)
>> 
> 
> Are you aware when can this be supported? I'm aware that Linaro's Qemu
> had something about it in TODO for their next release.
> 
> Also,
> 
> Are you aware what is the root of the problem of Qemu not being able
> to emulated correct pointer position with mouse device in VNC mode and
> requiring tablet? I'm aware of tablet vs mouse difference in specifing
> the coordinates (absolute vs relative). I'm just not aware why Qemu
> can't translate one into other correctly? I guess I must be missing
> something if this haven't been yet fixed.

For relative pointing devices, the guest does something called "mouse acceleration" where it tries to find out how quickly you're moving the mouse and set the pointer accordingly. Hence the coordinates the guest window management system thinks your mouse is on and the coordinates qemu would think they should be differ.

You can set acceleration to 1 with xset, giving you 1:1 translation of relative movement to absolute movement inside the guest.


Alex

Re: [Qemu-devel] qemu: hardware error: Failed to create USB device 'usb-tablet'

[dpc]

On Thu, Jun 30, 2011 at 9:56 AM, Peter Maydell <peter.maydell@linaro.org> wrote:

> You're probably thinking of the USB support in the OMAP3 beagle/overo
> models in qemu-linaro: different chip. I don't have any plans for
> vexpress USB support, I'm afraid. (We only have limited resources for
> qemu work and for most purposes the standard ps2 mouse works fine on
> vexpress.)

Thanks for clarification.

-- 
Dawid Ciężarkiewicz

Re: [Qemu-devel] qemu: hardware error: Failed to create USB device 'usb-tablet'

[dpc]

On Thu, Jun 30, 2011 at 10:01 AM, Alexander Graf <agraf@suse.de> wrote:
> For relative pointing devices, the guest does something called "mouse acceleration" where it tries to find out how quickly you're moving the mouse and set the pointer accordingly. Hence the coordinates the guest window management system thinks your mouse is on and the coordinates qemu would think they should be differ.
>
> You can set acceleration to 1 with xset, giving you 1:1 translation of relative movement to absolute movement inside the guest.

Thank you. This improves the cursor behavior a lot.

-- 
Dawid Ciężarkiewicz