Re: [PATCH 0/3] thunderbolt: Update XDomain vendor properties dynamically

[Greg KH]

On Fri, Aug 08, 2025 at 11:13:13AM +0200, Mika Westerberg wrote:
> On Fri, Aug 08, 2025 at 10:02:08AM +0100, Greg KH wrote:
> > On Fri, Aug 08, 2025 at 06:45:38AM +0200, Mika Westerberg wrote:
> > > On Thu, Aug 07, 2025 at 11:07:39AM -0500, Mario Limonciello wrote:
> > > > On 8/7/25 11:02 AM, Greg KH wrote:
> > > > > On Thu, Aug 07, 2025 at 07:15:33AM +0200, Mika Westerberg wrote:
> > > > > > On Wed, Aug 06, 2025 at 05:58:26PM +0100, Greg KH wrote:
> > > > > > > On Wed, Aug 06, 2025 at 05:00:24PM +0200, Mika Westerberg wrote:
> > > > > > > > On Wed, Aug 06, 2025 at 09:06:30AM -0500, Mario Limonciello wrote:
> > > > > > > > > On 8/6/2025 3:51 AM, Mika Westerberg wrote:
> > > > > > > > > > On Wed, Aug 06, 2025 at 11:46:04AM +0530, Rangoju, Raju wrote:
> > > > > > > > > > > 
> > > > > > > > > > > 
> > > > > > > > > > > On 7/28/2025 12:17 PM, Mika Westerberg wrote:
> > > > > > > > > > > > Hi,
> > > > > > > > > > > > 
> > > > > > > > > > > > On Tue, Jul 22, 2025 at 11:20:23PM +0530, Raju Rangoju wrote:
> > > > > > > > > > > > > This patch series aims to update vendor properties for XDomain
> > > > > > > > > > > > > dynamically for vendors like AMD, Intel and ASMedia.
> > > > > > > > > > > > 
> > > > > > > > > > > > The XDomain properties pretty much describe "software" not the underlying
> > > > > > > > > > > > hardware so I don't understand why this is needed? We could have some USB
> > > > > > > > > > > > IF registered Linux specific ID there but I don't see why this matters at
> > > > > > > > > > > > all.
> > > > > > > > > > > 
> > > > > > > > > > > Currently, it is showing up as "Intel" on AMD host controllers during
> > > > > > > > > > > inter-domain connection. I suppose an alternative is to just call it "Linux"
> > > > > > > > > > > or "Linux Connection Manager" to ensure we accurately represent the
> > > > > > > > > > > connections across different systems.
> > > > > > > > > > > 
> > > > > > > > > > > I appreciate your guidance on this and suggestions you might have.
> > > > > > > > > > 
> > > > > > > > > > Yeah, something like that (I prefer "Linux"). The "ID" still is 0x8086
> > > > > > > > > > though but I don't think that matters. AFAIK we have other "donated" IDs in
> > > > > > > > > > use in Linux. Let me check on our side if that's okay.
> > > > > > > > > 
> > > > > > > > > Having looked through this discussion I personally like "Linux" for this
> > > > > > > > > string too.
> > > > > > > > > 
> > > > > > > > > As for the vendor ID doesn't the LF have an ID assigned already of 0x1d6b?
> > > > > > > > > Would it make sense to use that?
> > > > > > > > 
> > > > > > > > AFAIK that's PCI ID, right? It should be USB IF assigned ID and LF is not
> > > > > > > > here at least:
> > > > > > > > 
> > > > > > > >    https://www.usb.org/members
> > > > > > > > 
> > > > > > > > If it really matters we can sure register one.
> > > > > > > 
> > > > > > > Linux has an official USB vendor id, we use it for when Linux is used as
> > > > > > > a USB gadget device and in a few other places.  If you want to reserve a
> > > > > > > product id from it, just let me know and I can dole it out (the list is
> > > > > > > around here somewhere...)
> > > > > > 
> > > > > > Yes please :) I think this is the right thing to do.
> > > > > 
> > > > > Great, please let me know why you need it and what it will be for and
> > > > > why.  I totally can not figure that out from this thread...
> > > > > 
> > > > > thanks,
> > > > > 
> > > > > greg k-h
> > > > 
> > > > Actually it's a very similar reason for the gadget drivers.  When connected
> > > > to other machines and using the USB4 networking feature (like a host to host
> > > > communication) the Linux kernel will identify itself and the other side will
> > > > show that to a user.
> > > > 
> > > > So right now it's got some hardcoded values.  This thread was prompting to
> > > > change the strings, but it's brought about the realization that we should
> > > > also be using a Linux specific vendor (the one uses in gadget devices) and
> > > > then a Linux specific "device id" which you will allocate.
> > > > 
> > > > Hope that helps!
> > > 
> > > Thanks Mario, yes exactly that :)
> > > 
> > > "Linux USB4 Inter-domain discovery properties" in a nutshell.
> > 
> > Ok, sounds good.  Here's the currently assigned ids that we have so far:
> > 
> > # Linux Foundation USB id list.
> > 1d6b  Linux Foundation
> >         0001  1.1 root hub
> >         0002  2.0 root hub
> >         0003  3.0 root hub
> >         0010  USB Debug Target
> >         0011  USB GDB Target
> >         0100  PTP Gadget
> >         0101  Audio Gadget
> >         0102  EEM Gadget
> >         0103  NCM (Ethernet) Gadget
> >         0104  Multifunction Composite Gadget
> >         0105  FunctionFS Gadget
> >         0106  Composite Gadget: ACM + Mass Storage
> >         0107  Embedded Hub Gadgetg
> >         0200  Qemu Audio Device
> >         0246  BlueZ Host Stack
> >         0247  BlueZ for Android
> > 
> > Any specific number feel drawn toward using?  Would 0004 make sense as this is
> > "USB 4" or should we save that if we ever get a USB 4.0 root hub?
> 
> 0004 USB4
> 
> sounds good to me. In USB4 there is no "root hub". It's called host router
> (but we do have device routers that are called USB4 hubs for added
> confusion ;-).
> 
> But I'm fine with other numbers too, does not matter if you want to save it
> for some future USB variant.

Ok, use 0004 for this.  But what should I use for the text string here
in the usb.ids file?

thanks,

greg k-h