Re: [PATCH v2 0/2] USB:ehci:fix the no SRBN register problem

From: Greg KH
Date: Fri Apr 09 2021 - 02:47:41 EST


On Fri, Apr 09, 2021 at 10:42:35AM +0800, liulongfang wrote:
> On 2021/4/8 22:53, Alan Stern wrote:
> > On Thu, Apr 08, 2021 at 09:49:18PM +0800, Longfang Liu wrote:
> >> (1) Add a whitelist for EHCI devices without SBRN registers.
> >> (2) Add Kunpeng920's EHCI device to the whitelist.
> >>
> >> Changes in v2:
> >> - Fix some code style issues.
> >> - Update function name.
> >>
> >> Longfang Liu (2):
> >> USB:ehci:Add a whitelist for EHCI controllers
> >> USB:ehci:fix Kunpeng920 ehci hardware problem
> >>
> >> drivers/usb/host/ehci-pci.c | 30 ++++++++++++++++++++++++++----
> >> 1 file changed, 26 insertions(+), 4 deletions(-)
> >
> > I don't think we need a whole list, along with an associated lookup
> > routine, when there are only two entries. The total amount of code will
> > be smaller if you just add a check for the Kunpeng920 controller to
> > the existing check for the STMICRO controller.
> >
> > Alan Stern
> > .
> >
> Now there are two EHCI controllers that do not have SBRN registers,
> and there may be more in the future. This list is added for subsequent
> compatibility if there are such controllers, instead of a series of if-else.

Why would more people create new EHCI controllers these days with the
cheapness of USB 3 cores? Anyway, let us worry about that if this list
gets "too long", a simple if statement is fine for now.

thanks,

greg k-h