Re: [RFC PATCH 1/2] usb: ehci: Add option to override ehci_readl()/ehci_writel()

[Daniel Palmer]

Hi Alan,

On Mon, 13 Jul 2026 at 23:46, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Mon, Jul 13, 2026 at 11:37:19PM +0900, Daniel Palmer wrote:
> > Hi Alan,
> >
> > On Mon, 13 Jul 2026 at 23:21, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote:
> > > > +config HAVE_BROKEN_EHCI_HCD
> > > > +     bool
> > >
> > > That is not a good choice of name; it's far too generic.  EHCI
> > > controllers can be broken in so many different ways...
> > >
> > > How about USB_EHCI_MMIO_OVERRIDES instead?
> >
> > Noted. Based on that we'd have a config for each piece that needs to
> > be overridden so drivers can pick the ones they need?
>
> Maybe.  What other things will need to be overridden?  It's hard to tell
> what you're planning from just a single sample.

For the fotg210 at least the location of the port status register
needs to be overridden, it doesn't support sITDs so that has to be
blocked, and the hardware has a bug where the length of ITDs is broken
so it needs to have a workaround to write the value it wants.

Cheers,

Daniel