[PATCH v2 2/2] USB: doc: Binding document for ehci-platform driver
stern at rowland.harvard.edu
Wed Oct 24 15:30:43 EDT 2012
On Wed, 24 Oct 2012, Mitch Bradley wrote:
> >> Ah, now I'm starting to get the picture.
> >> So by listing "usb-ehci" in its device ID table, a driver would
> >> essentially be saying that it can handle _all_ USB EHCI controllers.
> Actually, it means that the driver can handle at least USB EHCI
> controllers that are 100% compatible with the EHCI spec (requiring
> nothing extra). The driver might be able to handle almost-compatible
> controllers, possibly with the help of additional properties.
Unfortunately that's not saying very much. The EHCI spec describes
only PCI-based controllers. Every other sort does require something
> If a DT node lists "usb-ehci" as a "fallback", it's not guaranteed that
> a given version of that driver will work, but it's worth a try in the
> event that no more-specific driver is matched.
While I haven't checked in detail, it seems quite likely that this
would not work with some of the devices that have "usb-ehci" listed in
their compatible values.
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