From mboxrd@z Thu Jan 1 00:00:00 1970 From: mike@compulab.co.il (mike at compulab.co.il) Date: Sun, 14 Feb 2010 11:01:43 +0200 Subject: smsc911x suspend/resume In-Reply-To: References: <20100208144951.GF28972@buzzloop.caiaq.de> Message-ID: <20100214090143.GA23498@gentoodev.compulab.local> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Feb 11, 2010 at 06:26:32PM +0000, Steve.Glendinning at smsc.com wrote: > > Hmm, be careful about switching off power supplies that aren't supposed > > to be switched off while others are still powered. You can easily > > destroy hardware with that. Depending on how things are wired up > > internally, voltages can leak from one unit block to the other. Maybe > > Steve can can give a statement from official SMSC source about whether > > it is safe to switch off VDD33A in this case. > > I've checked with the chip architects, no power planes should be > externally > switched off in any suspend mode. The question if they *can* be switched off. With the hardware I have, most of 3.3V supplies are enabled/disabled with the same control. So, to have maximal power saving in the system, I just pull this control to disable 3.3V supplies, VDD33A among them. If smsc9220 can tolerate switching VDD33A during suspend, I can send a patch that allows proper wake-up with such conditions. > Steve