Spurious errors "ucsi_acpi USBC000:00: bogus connector number in CCI: 1" on 7.0-rc7

Spurious errors "ucsi_acpi USBC000:00: bogus connector number in CCI: 1" on 7.0-rc7

[Takashi Iwai]

Hi,

since 7.0-rc7, I'm getting a few errors
  ucsi_acpi USBC000:00: bogus connector number in CCI: 1
at boot of Thinkpad T14s Gen 6 AMD with a dock.

Obviously this came from the commit d2d8c17ac01a ("usb: typec: ucsi:
validate connector number in ucsi_notify_common()"), and reverting it
made it gone away.  I didn't notice anything practically broken either
before or after the revert, though -- the USB devices connected on the
dock keep working, at least.

Is this a firmware bug, or some missing piece in the code?
Judging from the message, it means that ucsi->cap.num_connectors is 0,
I suppose.


thanks,

Takashi

Re: Spurious errors "ucsi_acpi USBC000:00: bogus connector number in CCI: 1" on 7.0-rc7

[Greg Kroah-Hartman]

On Tue, Apr 07, 2026 at 07:38:50AM +0200, Takashi Iwai wrote:
> Hi,
> 
> since 7.0-rc7, I'm getting a few errors
>   ucsi_acpi USBC000:00: bogus connector number in CCI: 1
> at boot of Thinkpad T14s Gen 6 AMD with a dock.
> 
> Obviously this came from the commit d2d8c17ac01a ("usb: typec: ucsi:
> validate connector number in ucsi_notify_common()"), and reverting it
> made it gone away.  I didn't notice anything practically broken either
> before or after the revert, though -- the USB devices connected on the
> dock keep working, at least.
> 
> Is this a firmware bug, or some missing piece in the code?
> Judging from the message, it means that ucsi->cap.num_connectors is 0,
> I suppose.

Ugh, what's the odds this is an off-by-one error in the firmware? :)

Nathan and Heikki, any ideas?

thanks,

greg k-h

Re: Spurious errors "ucsi_acpi USBC000:00: bogus connector number in CCI: 1" on 7.0-rc7

[Nathan Rebello]

On Tue, Apr 07, 2026 at 07:58:00AM +0200, Greg Kroah-Hartman wrote:
> On Tue, Apr 07, 2026 at 07:38:50AM +0200, Takashi Iwai wrote:
> > Is this a firmware bug, or some missing piece in the code?
> > Judging from the message, it means that ucsi->cap.num_connectors is 0,
> > I suppose.
>
> Ugh, what's the odds this is an off-by-one error in the firmware? :)
>
> Nathan and Heikki, any ideas?

This isn't an off-by-one or firmware bug. Takashi is right that
num_connectors is 0. The validation checks against
ucsi->cap.num_connectors, but notifications can arrive before
ucsi_init() has populated that field via GET_CAPABILITY.

Pre-init notifications are already handled safely by the early-event
guard in ucsi_connector_change(), so the fix is to skip validation
when num_connectors hasn't been initialized yet.

Sending a fix shortly.

Thanks,
Nathan