Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752614AbaJIIC5 (ORCPT ); Thu, 9 Oct 2014 04:02:57 -0400 Received: from mail-vc0-f178.google.com ([209.85.220.178]:33791 "EHLO mail-vc0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750853AbaJIICp (ORCPT ); Thu, 9 Oct 2014 04:02:45 -0400 MIME-Version: 1.0 In-Reply-To: <20140926133920.GG7422@leverpostej> References: <1394052739-8589-1-git-send-email-marek@goldelico.com> <1394052739-8589-4-git-send-email-marek@goldelico.com> <20140922110320.GI3290@leverpostej> <20140926133920.GG7422@leverpostej> Date: Thu, 9 Oct 2014 10:02:43 +0200 Message-ID: Subject: Re: [PATCH v2] Documentation: DT: Document twl4030-madc-battery bindings. From: Belisko Marek To: Mark Rutland Cc: "robh+dt@kernel.org" , Pawel Moll , "ijc+devicetree@hellion.org.uk" , "galak@codeaurora.org" , "rob@landley.net" , "dbaryshkov@gmail.com" , "dwmw2@infradead.org" , "grant.likely@linaro.org" , "hns@goldelico.com" , "sre@debian.org" , "devicetree@vger.kernel.org" , "linux-doc@vger.kernel.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Mark, On Fri, Sep 26, 2014 at 3:39 PM, Mark Rutland wrote: > On Mon, Sep 22, 2014 at 09:35:03PM +0100, Belisko Marek wrote: >> Hi Mark, >> >> On Mon, Sep 22, 2014 at 1:03 PM, Mark Rutland wrote: >> > Hi, >> > >> > On Wed, Mar 05, 2014 at 08:52:19PM +0000, Marek Belisko wrote: >> >> Signed-off-by: Marek Belisko >> >> --- >> >> .../bindings/power_supply/twl4030_madc_battery.txt | 43 ++++++++++++++++++++++ >> >> 1 file changed, 43 insertions(+) >> >> create mode 100644 Documentation/devicetree/bindings/power_supply/twl4030_madc_battery.txt >> >> >> >> diff --git a/Documentation/devicetree/bindings/power_supply/twl4030_madc_battery.txt b/Documentation/devicetree/bindings/power_supply/twl4030_madc_battery.txt >> >> new file mode 100644 >> >> index 0000000..fd0b6d2 >> >> --- /dev/null >> >> +++ b/Documentation/devicetree/bindings/power_supply/twl4030_madc_battery.txt >> >> @@ -0,0 +1,43 @@ >> >> +twl4030_madc_battery >> >> + >> >> +Required properties: >> >> + - compatible : "ti,twl4030-madc-battery" >> > >> > I'm rather confused by this; the code seems to have stripped away all >> > the twl4030 dependencies and this now seems to be a generic ADC battery >> > status driver. So why does this need to be specific to twl4030? >> You are right. Also possibly driver name is incorrect :). Better name could be >> ti, madc-battery. > > Ok. > >> > >> >> + - capacity : battery capacity in uAh >> > >> > I would make the units explicit in the name; "capacity" can be measured >> > in many ways. >> OK capacity_uAh should be fine I believe. > > Well, "capacity-uah" to match naming conventions. OK. > >> > >> >> + - charging-calibration-data : list of voltage(mV):level(%) values >> >> + for charging calibration (see example) >> >> + - discharging-calibration-data : list of voltage(mV):level(%) values >> >> + for discharging calibration (see example) >> > >> > Regardless of the prefixing of these property names, the specifics are >> > unclear to me. >> Do you suggest to rename it completely or is enough to add "ti, " prefix? > > I'm not suggesting prefixing. I'm suggesting that "calibration data" > could mean a variety of things, so having a more specific name would be > beneficial. Charging and discharging data are used for some kind of interpolation within voltage interval. So we get volume from ADC and then convert it according charging/discharging table to some value which is then useded in various battery properties (status, charge_now, capacity, time_to_empty_now). So maybe battery-charging/discharging-calibration-data could be property name? > >> > Does this apply to vbat? >> Yes bat is read and then interpolation algorithm is applied for >> various power properties. >> So mapping from voltage to percentage is defined in table. >> > >> > Is vbat guaranteed to read in mV? >> Yes. >> > >> > Is any particular order required? The example seems to go be in >> > descending percentage values. >> There is done sorting in driver so ordering it's not necessary. >> > >> > Is any particular interpolation expected on behalf of the OS, or is this >> > just an informative set of measurements that hte OS can use as it sees >> > fit? >> > >> >> + - io-channels: Should contain IIO channel specifiers >> >> + for each element in io-channel-names. >> >> +- io-channel-names: Should contain the following values: >> All 3 statements was copied from rx51-battery and documentation is the same. >> There is not unit for all channels just raw values which are then >> converted in driver. > > I don't understand. How do you figure out the mapping of those raw > values to sensible units? Surely you need additional information to do > so? Yes mapping from raw values is done in driver. Like current read from iio channel_ichg is multiplied by 1000 or read from channel_temp is multiplied by 10 to have proper values for battery properties. > > Mark. BR, marek -- as simple and primitive as possible ------------------------------------------------- Marek Belisko - OPEN-NANDRA Freelance Developer Ruska Nova Ves 219 | Presov, 08005 Slovak Republic Tel: +421 915 052 184 skype: marekwhite twitter: #opennandra web: http://open-nandra.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/