Re: [PATCH] phy: usb: fix Broadcom driver table indexing error

[Sam Edwards]

On Thu, Oct 3, 2024 at 3:47 PM Florian Fainelli
<florian.fainelli@xxxxxxxxxxxx> wrote:
>
> On 10/3/24 14:17, Sam Edwards wrote:
> > The Broadcom USB PHY driver contains a lookup table
> > (`reg_bits_map_tables`) to resolve register bitmaps unique to certain
> > versions of the USB PHY as found in various Broadcom chip families.
> > Historically, this table was just kept carefully in sync with the
> > "selector" enum every time the latter changed to ensure consistency.
> > However, a recent commit (see 'fixes' tag) introduced two new
> > enumerators but did not adjust the array for BCM4908, thus breaking the
> > xHCI controller (and boot process) on this platform and revealing the
> > fragility of this approach.
> >
> > Since these arrays are a little sparse (many elements are zero) and the
> > position of the array elements is significant only insofar as they agree
> > with the enumerators, designated initializers are a better fit than
> > positional initializers here. Convert this table accordingly, fixing the
> > boot-time crash on BCM4908 in the process.
> >
> > Fixes: 4536fe9640b6 ("phy: usb: suppress OC condition for 7439b2")
> > Signed-off-by: Sam Edwards <CFSworks@xxxxxxxxx>

Hi Florian,

>
> Thanks a bunch for the fix, good catch! Sorry to ask you this, but since
> this is intended to be backported to stable trees at some point, would
> you mind breaking this up in two commits:
>
> - one which is easy to review and audit and which adjusts the BCM4908 entry
> - another one which converts to using designated index constants?

Not a problem at all! I'd much rather address feedback like this
myself so I can practice the proper formatting than have you take care
of it. I'll send a split-up v2 in a moment. :)

Kind regards,
Sam

>
> Thanks!
> --
> Florian