Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756653AbaFZPqS (ORCPT ); Thu, 26 Jun 2014 11:46:18 -0400 Received: from mail-vc0-f175.google.com ([209.85.220.175]:33275 "EHLO mail-vc0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755517AbaFZPqQ (ORCPT ); Thu, 26 Jun 2014 11:46:16 -0400 MIME-Version: 1.0 In-Reply-To: <1403785148-20792-3-git-send-email-ch.naveen@samsung.com> References: <1403785148-20792-1-git-send-email-ch.naveen@samsung.com> <1403785148-20792-3-git-send-email-ch.naveen@samsung.com> Date: Thu, 26 Jun 2014 08:46:14 -0700 X-Google-Sender-Auth: KIgWyBBEUjQtRy1LELSeWz5cTws Message-ID: Subject: Re: [PATCH 2/3] ARM: DTS: Add NTC thermistor nodes to Exynos5250 based Snow From: Doug Anderson To: Naveen Krishna Chatradhi Cc: linux-samsung-soc , "devicetree@vger.kernel.org" , linux-iio , "linux-kernel@vger.kernel.org" , Greg Kroah-Hartman , Naveen Krishna , "cpgs ." , Tushar Behera Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Naveen, On Thu, Jun 26, 2014 at 5:19 AM, Naveen Krishna Chatradhi wrote: > Exynos5250 based Snow board has 4 NTC thermistors to measure > temperatures at various points on the board. > > IIO based ADC becomes the parent and NTC thermistors are the childs, > via the HWMON interface. > > Signed-off-by: Naveen Krishna Chatradhi > --- > Posted earlier by Doug Anderson @ https://lkml.org/lkml/2013/3/27/453 > > This patch depends on (1/4 and 2/4 patches of) patchset posted > http://www.spinics.net/lists/linux-iio/msg13486.html > Which were applied on to Guenter Roeck's tree. > > cat sysfs entries exported by hwmon for 4 thermistors > and verified the values on Snow. > > arch/arm/boot/dts/exynos5250-snow.dts | 34 +++++++++++++++++++++++++++++++++ > 1 file changed, 34 insertions(+) NAK. The first chunk of exynos5250-snow devices have the thermistors populated, but a huge chunk of devices also _don't_ have them populated. If I remember my history properly, rev3 and earlier all had thermistors. Some of rev4 might have thermistors (I never got a clear answer). ...and rev5 definitely doesn't have resistors. Aside from thermistors there's no good reason to differentiate rev3 and rev4 (they just have different memory). The upstream kernel may eventually need to differentiate rev4 and rev5 since they have a different audio codec. See for some descriptions of the different revisions of snow and how they were handled in the Chrome OS tree. See for thermistors talk. Patch set #1 actually split out rev3, but we then decided that we really didn't need to use the thermistors on any of the revisions so the later patchsets just totally take them out. -Doug -- 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/