linux-kernel - Re: [PATCH v2 2/3] clk: ti: check clock type before doing autoidle ops

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Message-ID: <20181130153729.GG53235@atomide.com>
Date:   Fri, 30 Nov 2018 07:37:29 -0800
From:   Tony Lindgren <tony@...mide.com>
To:     Tero Kristo <t-kristo@...com>
Cc:     Stephen Boyd <sboyd@...nel.org>,
        Andreas Kemnade <andreas@...nade.info>, bcousson@...libre.com,
        letux-kernel@...nphoenux.org, linux-clk@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-omap@...r.kernel.org,
        mturquette@...libre.com, paul@...an.com
Subject: Re: [PATCH v2 2/3] clk: ti: check clock type before doing autoidle
 ops

Hi,

* Tero Kristo <t-kristo@...com> [181130 09:21]:
> On 30/11/2018 09:57, Stephen Boyd wrote:
> > No that is not preferred. Can the omap2_clk_deny_idle() function be
> > integrated closer into the clk framework in some way that allows it to
> > be part of the clk_ops structure? And then have that take a clk_hw
> > structure instead of a struct clk? I haven't looked at this in any
> > detail whatsoever so I may be way off right now.
> 
> It could be added under the main clk_ops struct, however this would
> introduce two new func pointers to it which are not used by anything else
> but OMAP. Are you aware of any other platforms requiring similar feature?

>From consumer usage point of view, I'm still wondering about
the relationship of clk_deny_idle() and clkdm_deny_idle().

It seems that we need to allow reset control drivers call
clk_deny_idle() for the duration of reset. And it seems the
clk_deny_idle() should propagate to also up to the related
clock domain driver to do clkdm_deny_idle().

So maybe clk_deny_idle() is could just be something like:

dev = clk_get_device(clk);
...
error = pm_runtime_get(dev);
...
pm_runtime_put(dev);
...

And that way it would just propagate to the parent clock
domain driver and the clock framework does not need to know
about clockdomains. A clockdomain could be just a genpd
domain.

Or do you guys have better ideas?

Regards,

Tony