From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [PATCH] tpm: do not suspend/resume if power stays on Date: Wed, 1 Mar 2017 11:43:33 -0700 Message-ID: <20170301184333.GA12197@obsidianresearch.com> References: <20170301115116.19696-1-enric.balletbo@collabora.com> <20170301135429.GF28874@leverpostej> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20170301135429.GF28874@leverpostej> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tpmdd-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Mark Rutland Cc: tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Rob Herring , Sonny Rao , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: tpmdd-devel@lists.sourceforge.net > > +Optional properties: > > +- powered-while-suspended: present when the TPM is left powered on between > > + suspend and resume (makes the suspend/resume callbacks do nothing). > > This reads like configuration rather than a HW property. I read this to mean the HW does not cut power to the TPM when Linux does 'suspend'. We recently added global suspend/resume callbacks to the TPM core. Those call backs do not power off the TPM, they just prepare its internal state to loose power to the chip. Skipping that process on hardware that does not power-off the TPM makes sense to me. But, Sonny, perhaps this should be a global flag in tpm_chip, not a per-interface-driver override? Jason ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot