On 09/22/2017 06:03 AM, Linus Walleij wrote:

On Thu, Sep 21, 2017 at 3:04 AM, Florian Fainelli [off-list ref] wrote:

quoted

Some platforms (e.g: Broadcom STB: BMIPS_GENERIC/ARCH_BRCMSTB) will lose
their register contents when entering their lower power state. In such a
case, the pinctrl-single driver that is used will not be able to restore
the power states without telling the core about it and having
pinctrl_select_state() check for that.

This patch adds a new optional boolean property that Device Tree can
define in order to obtain exactly that and having the core pinctrl code
take that into account.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

If we use this per-controller approach rather than the per-state approach
I discuss in reply to patch 1/2, we should probably make it a generic
property for pin controllers and not just a pinctrl-single business.

I suppose it makes sense to make this a generic pinctrl property then.
drivers/pinctrl/core.c does not appear to be trying to fetch any
properties for a pinctrl device, but that is probably not too hard to add.

So patch pinctrl-bindings.txt and put the code somewhere in
core.

But that is more of a detail, first we need to figure out how to
handle this business in general.

Fair enough.
-- 
Florian