Re: [PATCH 3/5] mfd: wm5110: Add delay before releasing reset line on cold boot

From: Mark Brown
Date: Mon Mar 16 2015 - 16:47:28 EST


On Mon, Mar 16, 2015 at 06:45:18PM +0000, Charles Keepax wrote:

> I think your suspend example is pretty tricky, we enable the
> regulators for the core_supplies at boot, so I guess we have
> requested that the system never removes those so if it does so
> anyway perhaps that is a system problem? There isn't really

No, there's no guarantee that the current state is maintained over
system suspend - system suspend can turn anything off (at least from an
API point of view).

> That would leave the only possible solution being a hard reset
> during every runtime resume but that makes me very nervous about
> the AoD interrupts as state for those would be lost upon that
> reset.

No, you're guaranteed that the supply will stay on while the system is
running so runtime PM is not an issue - it's system suspend that's an
issue.

> All in all, I really struggle to see what more the driver could
> do here.

As I suggested in my original reply handle system suspend.

Attachment: signature.asc
Description: Digital signature