From mboxrd@z Thu Jan 1 00:00:00 1970 From: YH Huang Subject: Re: [PATCH] sbs-battery: fix power status when battery is dry Date: Mon, 28 Mar 2016 10:32:10 +0800 Message-ID: <1459132330.16645.14.camel@mtksdaap41> References: <1458726794-48298-1-git-send-email-yh.huang@mediatek.com> <1458801832.16645.7.camel@mtksdaap41> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-pm-owner@vger.kernel.org To: Daniel Kurtz Cc: Sebastian Reichel , Dmitry Eremin-Solenikov , David Woodhouse , Matthias Brugger , linux-pm@vger.kernel.org, "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "moderated list:ARM/Mediatek SoC support" List-Id: linux-mediatek@lists.infradead.org On Fri, 2016-03-25 at 11:06 +0800, Daniel Kurtz wrote: > On Thu, Mar 24, 2016 at 2:43 PM, YH Huang wro= te: > > > > Hi Daniel, > > > > On Thu, 2016-03-24 at 12:01 +0800, Daniel Kurtz wrote: > > > Hi YH, > > > > > > On Wed, Mar 23, 2016 at 5:53 PM, YH Huang = wrote: > > > > When the battery is dry and BATTERY_FULL_DISCHARGED is set, > > > > we should check BATTERY_DISCHARGING to decide the power status. > > > > If BATTERY_DISCHARGING is set, the power status is not charging= =2E > > > > Or the power status should be charging. > > > > > > > > Signed-off-by: YH Huang > > > > --- > > > > drivers/power/sbs-battery.c | 22 ++++++++++++---------- > > > > 1 file changed, 12 insertions(+), 10 deletions(-) > > > > > > > > diff --git a/drivers/power/sbs-battery.c b/drivers/power/sbs-ba= ttery.c > > > > index d6226d6..d86db0e 100644 > > > > --- a/drivers/power/sbs-battery.c > > > > +++ b/drivers/power/sbs-battery.c > > > > @@ -382,11 +382,12 @@ static int sbs_get_battery_property(struc= t i2c_client *client, > > > > > > > > if (ret & BATTERY_FULL_CHARGED) > > > > val->intval =3D POWER_SUPPLY_STATUS_FUL= L; > > > > - else if (ret & BATTERY_FULL_DISCHARGED) > > > > - val->intval =3D POWER_SUPPLY_STATUS_NOT= _CHARGING; > > > > - else if (ret & BATTERY_DISCHARGING) > > > > - val->intval =3D POWER_SUPPLY_STATUS_DIS= CHARGING; > > > > - else > > > > + else if (ret & BATTERY_DISCHARGING) { > > > > + if (ret & BATTERY_FULL_DISCHARGED) > > > > + val->intval =3D POWER_SUPPLY_ST= ATUS_NOT_CHARGING; > > > > + else > > > > + val->intval =3D POWER_SUPPLY_ST= ATUS_DISCHARGING; > > > > + } else > > > > > > > > > I think (BATTERY_DISCHARGING && BATTERY_FULL_DISCHARGED) is still > > > POWER_SUPPLY_STATUS_DISCHARGING. > > > So, let's just report what the battery says and do: > > > > > > else if (ret & BATTERY_DISCHARGING) > > > val->intval =3D POWER_SUPPLY_STATU= S_DISCHARGING; > > > > > So we just ignore the special situation (BATTERY_DISCHARGING && > > BATTERY_FULL_DISCHARGED). > > Isn't POWER_SUPPLY_STATUS_NOT_CHARGING a useful information? >=20 > The battery is discharging. The fact that it is also reporting that > it is already "discharged" just seems premature. I would expect to > only see NOT_CHARGING if completely discharged *and* not discharging. I check the "Smart Battery Data Specification Revision 1.1". And there are some words about FULLY_DISCHARGED. "Discharge should be stopped soon." "This status bit may be set prior to the =E2=80=98TERMINATE_DISCHARGE_ALARM=E2=80=99 as an early or first level = warning of end of battery charge." It looks like the FULLY_DISCHARGED status is used to announce the warning of battery charge and it is still discharging if there is no on= e takes care of it.