Re: [PATCH v4 4/4] ARM: mvebu: Armada 385 GP: Add regulators to the SATA port

From: Hans de Goede
Date: Sat Jan 17 2015 - 09:29:39 EST


Hi,

On 17-01-15 14:14, Mark Brown wrote:
On Sat, Jan 17, 2015 at 09:48:57AM +0100, Hans de Goede wrote:

and leave these regulators on, rather then turn them of $random time,
because as I've advocated before (see the simplefb thread) there is
no simple magic moment when it is right to turn things off, so doing
it when userspace starts is more or less as good as any moment, and if
it turns out that that is not a good moment, then maybe we need to
re-think the turning off in general.

Following your argument to the logical conclusion means we can never
turn any regualtor off - we always have the risk that there's another
shared user which is going to get a power bounce if we power down. More
directly we'll also get people complaining that we're burning power
pointlessly on their systems for devices they've not even got drivers
enabled for. This powering down is something there's been user demand
for.

Right, note I'm only advocating to not turn off regulators marked as
regulator-boot-on. I would expect any regulator to have such a
marking to have at least one user with an actual driver. If people decide
to not build that driver, and then complain we can simply tell them to
build the driver ...

Regards,

Hans
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