Re: [PATCH] sh_eth: ensure pm_runtime cannot suspend the device during init

[Ben Dooks <ben.dooks@codethink.co.uk>]

On 14/03/14 20:06, Sergei Shtylyov wrote:
> Hello.
>
> On 03/14/2014 10:01 PM, Ben Dooks wrote:
>
>>> It seems the pm_rumtime work queue is causing the device to be suspended
>>> during initialisation, thus the initialisation may not be able to access
>>> registers properly. Use pm_runtime_get_sync() and pm_runtime_put_sync()
>>> to ensure that the pm system does not suspend it during the probe()
>>> call.
>
>> If this work's for Geert then I'll look into updating the header and
>> sending it to the netdev list.
>
>     I keep wondering why I'm seeing no issues in my setup... I don't
> have drivers/sh/ patch and have CONFIG_PM_RUNTIME=y. Seeing no issues on
> multiplatform kernels on neither Lager nor Koelsch (however, other
> platforms are not enabled).

Without drivers/sh there is no specification to the pm code to do
anything with the platform or OF devices. This means the clocks are
not being auto-managed, which in turn means the clock is probably
being left on from the boot-loader and thus the unit works correctly.

Unfortunately, without drivers/sh patched a number of other drivers
fail to work. This means we need it or something similar in the kernel.

I will spend some time over the weekend moving the code out of the
drivers/sh to somewhere else so that this does not occur again.


-- 
Ben Dooks				http://www.codethink.co.uk/
Senior Engineer				Codethink - Providing Genius