BUG: [PATCH v2] isoc: mediatek: Check for error clk pointer

[Guenter Roeck]

On Fri, Jan 28, 2022 at 10:51:20AM +0100, Frank Wunderlich wrote:
> Hi,
> 
> this commit is merged in 5.17-rc1 and breaks scpsys on mt7622/bananapi R64
> 
> mtk-scpsys: probe of 10006000.power-controller failed with error -2
> 
> at least ethernet is affected (i guess usb,sata,btif,... too, but not checked), as gmacs do not get probed as depency of it
> 
> after reverting this commit it is working again.
> 
> have not yet digged deeper into it why it is failing, but maybe author has an idea
> 

I created a revert of the problematic patch with some explanation.

https://lore.kernel.org/lkml/20220205014755.699603-1-linux@roeck-us.net/

Sorry that I didn't reference this discussion; I only noticed it after
I wrote the revert. The revert and my analysis is based on the impact
of this patch on affected Chromebooks.

The revert is queued for v4.19.y and later stable releases because
the patch discussed here made it into all those releases and breaks
pretty much all Mediatek based systems using the affected driver.

Guenter