On Tue, Oct 01, 2019 at 04:09:05PM +0300, Mika Westerberg wrote: > On Tue, Oct 01, 2019 at 02:47:48PM +0200, Greg Kroah-Hartman wrote: > > > - Thunderbolt Controller driver. This driver is required if you > > > - want to hotplug Thunderbolt devices on Apple hardware or on PCs > > > - with Intel Falcon Ridge or newer. > > > + USB4 (Thunderbolt) driver. USB4 is the public spec based on > > > + Thunderbolt 3 protocol. This driver is required if you want to > > > + hotplug Thunderbolt and USB4 compliant devices on Apple > > > + hardware or on PCs with Intel Falcon Ridge or newer. > > > > Wait, did "old" thunderbolt just get re-branded as USB4? > > Not but the driver started supporting USB4 as well :) > > USB4 is pretty much public spec of Thunderbolt 3 but with some > differences in register layouts (this is because Thunderbolt uses some > vendor specific capabilities which are now moved to more "standard" > places). Ok, then we need to rename the Kconfig option as well, otherwise no one will "know" that this changed, so they will not be prompted for it. > > Because if I have an "old" laptop that needs Thunderbolt support, how am > > I going to know it is now called USB4 instead? > > Well the Kconfig option tries to have both names there: > > tristate "USB4 (Thunderbolt) support" > > and then > > USB4 (Thunderbolt) driver. USB4 is the public spec based on > Thunderbolt 3 protocol. This driver is required if you want to hotplug > Thunderbolt and USB4 compliant devices on Apple hardware or on PCs > with Intel Falcon Ridge or newer. > > and the Kconfig option is still CONFIG_THUNDERBOLT. I know this is > confusing but I don't have better ideas how we can advertise both. I > borrowed this "format" from firewire. CONFIG_USB4 instead? > > Shouldn't there just be a new USB4 option that only enables/builds the > > USB4 stuff if selected? Why would I want all of this additional code on > > my old system if it's not going to do anything at all? > > USB4 devices are backward compatible with Thunderbolt 3 so you should be > able to plug in USB4 device to your old Thunderbolt 3 laptop for > example. It goes the other way as well. Some things are optional but for > example USB4 hubs must support also Thunderbolt 3. > > Does that clarify? Yes, it does, looks like marketing just renamed an old functioning system into a "brand new one!" :) thanks, greg k-h
