From mboxrd@z Thu Jan 1 00:00:00 1970 From: pavel@ucw.cz (Pavel Machek) Date: Fri, 4 May 2018 22:20:44 +0200 Subject: Motorola Droid 4 progress, power consumption In-Reply-To: <20180503142240.GQ98604@atomide.com> References: <20180501183148.GA26996@amd> <20180502144158.GJ98604@atomide.com> <20180503090611.GA14451@amd> <20180503142240.GQ98604@atomide.com> Message-ID: <20180504202044.GC22519@amd> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi! > > user at devuan:/sys/class/power_supply/battery$ date; cat current_now > > current_avg > > Thu May 3 09:33:07 CEST 2018 > > -56000 > > -72308 > > user at devuan:/sys/class/power_supply/battery$ date; cat current_now > > current_avg > > Thu May 3 09:33:08 CEST 2018 > > -37000 > > -211362 > > I recall it just being calculated based on the time between > the reads. Hard to say what it does, -ENODOCS.. Maybe the mc13783 > PMIC docs have something similar. Hmm. current_avg is world readable; if it does changes to the hardware, that's somehow bad. But I guess I can sample charge_counter every minute or so and get what I need? > > > Hmm oh and the POWER_SUPPLY_CHARGE_COUNTER value should be monitored > > > by your libbattery and it's low value and high value should be saved > > > to a file. Low should be saved when we get the battery low interrupt > > > and battery state changes to POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL. > > > High value should be saved on POWER_SUPPLY_CAPACITY_LEVEL_FULL. > > > > > > Then when you know the high value and low value, you can calculate > > > the remaining capacity based on the current value and > > > POWER_SUPPLY_POWER_AVG. > > > > I'll look into that... but probably will do experiments with python, > > first. > > Sure. The reason why I think we should not do it in the kernel in > addition to the earlier reasoning is that we don't have a place > to store the min and max values across reboot. I think there's > some flash on the battery over 1w bus, but it probably just > contains battery serial number or something and is not intended > for writing much to it. I guess the min and max values should be > really keyd based on this battery id in case the battery gets > changed. I agree this should not be done in kernel as it requires persistent storage. Battery is not user-replacable (and this will recalibrate itself on charge/discharge cycle) so.. I don't think keying is strictly neccessary for D4. Best regards, Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 181 bytes Desc: Digital signature URL: