Re: [Linaro-acpi] [PATCH v3 1/3] Mailbox: Add support for PCC mailbox and channels

[Arnd Bergmann <arnd@arndb.de>]

On Wednesday 03 September 2014 11:23:21 Ashwin Chaugule wrote:
> On 2 September 2014 19:03, Mark Brown <broonie@kernel.org> wrote:
> > On Tue, Sep 02, 2014 at 04:15:05PM -0400, Ashwin Chaugule wrote:
> >
> >> > Using platform_data would no be helpful, because there is no platform
> >> > code to fill that out on ACPI based systems.
> >
> >> Right. So the question is how do we work around the "mbox->dev" and
> >> "client->dev" expectations in the Mailbox framework for PCC, given
> >> that these tables aren't backed by "struct devices" ?
> >
> > As previously suggested just looking things up in the context of a
> > device created to represent the PCC controller seems fine; clients know
> > they're using PCC so can just call a PCC specific API which hides the
> > mechanics from them (for example, using a global variable to store the
> > device).
> 
> IIUC, this means, either modifying the existing
> mbox_controller_register() to know when a PCC mbox is being added, or
> have another PCC specific API for registering as a mailbox? Then, in
> the PCC specific API that requests a PCC channel, depending on what we
> do in the registration path, this function can pick out the PCC
> mailbox pointer and try_module_get(mbox->dev..). Since this is PCC
> specific anyway, we don't need the client->dev argument at all. Did I
> understand you correctly?

Yes, I think this would be reasonable. 

	Arnd