From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752807AbbDAQrj (ORCPT ); Wed, 1 Apr 2015 12:47:39 -0400 Received: from mo4-p00-ob.smtp.rzone.de ([81.169.146.220]:13088 "EHLO mo4-p00-ob.smtp.rzone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751764AbbDAQrf convert rfc822-to-8bit (ORCPT ); Wed, 1 Apr 2015 12:47:35 -0400 X-RZG-AUTH: :JGIXVUS7cutRB/49FwqZ7WcKdUCnXG6JabOfSXKWrat/hNPvz+KM X-RZG-CLASS-ID: mo00 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) Subject: Re: [PATCH v4 3/6] Documentation: DT: Document twl4030-madc-battery bindings From: "Dr. H. Nikolaus Schaller" In-Reply-To: Date: Wed, 1 Apr 2015 18:46:59 +0200 Cc: Marek Belisko , Benoit Cousson , Tony Lindgren , Sebastian Reichel , Dmitry Eremin-Solenikov , David Woodhouse , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , linux-omap , "linux-arm-kernel@lists.infradead.org" , "linux-pm@vger.kernel.org" Content-Transfer-Encoding: 8BIT Message-Id: <034B4896-E7D1-4860-ADBE-78C4DB7C4B11@goldelico.com> References: <1426022847-30912-1-git-send-email-marek@goldelico.com> <1426022847-30912-4-git-send-email-marek@goldelico.com> To: Rob Herring X-Mailer: Apple Mail (2.1878.6) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Am 01.04.2015 um 18:30 schrieb Rob Herring : > On Tue, Mar 10, 2015 at 4:27 PM, 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..d3dd9d8 >> --- /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" > > Is this a sub-node of the twl4030 or something? Please define where > this fits (hint: I would expect to be a sub node of a charging > controller or battery monitor). It is a driver connecting some battery parameters with measurements provided by the twl4030-madc to present a /sys/class/power_supply node for the battery with a coarse estimate for the charging level. So maybe the best wording is that it is a battery-driver assuming a twl4030-madc providing raw measurements (voltage, charging). Therefore it could as well be battery-twl4030-madc. > >> + - capacity-uah : battery capacity in uAh >> + - ti,volt-to-capacity-charging-map : list of voltage(mV):level(%) values >> + for charging calibration (see example) >> + - ti,volt-to-capacity-discharging-map : list of voltage(mV):level(%) values >> + for discharging calibration (see example) > > These seem like properties of the battery independent of the > battery/charging controller which is the twl4030. Ideally we would > define battery nodes generically and independent of the charge > controllers. Then there are smart batteries to consider too. For smart batteries there are completely independent mechanisms like I2C and HDQ/1-wire communication with fuel gauge chips (e.g. b27xxx). Those do not need such battery properties because they are stored in EEPROMs within these chips. So all this is a quite special solution just for those handful of board that have no smart battery and use exactly this twl4030 chip. It is not intended to become a generic charging/fuel solution. Just make it work with DT (it worked with platform_data since ~3.12). BR, Nikolaus > > Rob > >> + - io-channels: Should contain IIO channel specifiers >> + for each element in io-channel-names. >> +- io-channel-names: Should contain the following values: >> + * "temp" - The ADC channel for temperature reading >> + * "ichg" - The ADC channel for battery charging status >> + * "vbat" - The ADC channel to measure the battery voltage >> + >> +Example: >> + madc-battery { >> + compatible = "ti,twl4030-madc-battery"; >> + capacity-uah = <1200000>; >> + ti,volt-to-capacity-charging-map = <4200 100>, >> + <4100 75>, >> + <4000 55>, >> + <3900 25>, >> + <3800 5>, >> + <3700 2>, >> + <3600 1>, >> + <3300 0>; >> + >> + ti,volt-to-capacity-discharging-map = <4200 100> >> + <4100 95>, >> + <4000 70>, >> + <3800 50>, >> + <3700 10>, >> + <3600 5>, >> + <3300 0>; >> + io-channels = <&twl_madc 1>, >> + <&twl_madc 10>, >> + <&twl_madc 12>; >> + io-channel-names = "temp", >> + "ichg", >> + "vbat"; >> + }; >> -- >> 1.9.1 >>