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[209.132.180.67]) by mx.google.com with ESMTP id h8-v6si25263185pli.474.2018.05.08.10.45.24; Tue, 08 May 2018 10:45:38 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=1rebcenu; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755639AbeEHRoy (ORCPT + 99 others); Tue, 8 May 2018 13:44:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:33386 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755587AbeEHRoe (ORCPT ); Tue, 8 May 2018 13:44:34 -0400 Received: from mail-qk0-f174.google.com (mail-qk0-f174.google.com [209.85.220.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 953632183B; Tue, 8 May 2018 17:44:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1525801473; bh=6mNJBC0ATPaODrgIxMG5Y62ZWnK4jtKPATJWSJQsh/s=; h=In-Reply-To:References:From:Date:Subject:To:Cc:From; b=1rebcenu1z8UnrJ3wQP6+soUUhppkvJDPD55dhKMfja18Xl6AwuUEvZi+mtpg7fkn h8PNiR5tsVTRnkINkaaZdeeOq6zaJhgSgcdvs4RRWo6IuNeeYRSnr0ju6eLzEQCVXK fLEBUwbHBhGrHQH8bXVGLZtXA/7IwV6TziZxEyMg= Received: by mail-qk0-f174.google.com with SMTP id l132so2638036qke.3; Tue, 08 May 2018 10:44:33 -0700 (PDT) X-Gm-Message-State: ALKqPwcDIwSDwi97RjAhJ94CJ7LYt7PqQXtLRk3gY6TNchMpNsDfl50O cDkaRXS+jL+VMZc+AQbohR3NliDTbom8vgO5Ow== X-Received: by 10.233.224.13 with SMTP id m13mr1743947qkk.43.1525801472790; Tue, 08 May 2018 10:44:32 -0700 (PDT) MIME-Version: 1.0 Received: by 10.12.155.2 with HTTP; Tue, 8 May 2018 10:44:12 -0700 (PDT) In-Reply-To: <20180508145611.49072-4-giulio.benetti@micronovasrl.com> References: <20180508145611.49072-1-giulio.benetti@micronovasrl.com> <20180508145611.49072-4-giulio.benetti@micronovasrl.com> From: Rob Herring Date: Tue, 8 May 2018 12:44:12 -0500 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 4/4] rtc: ds1307: add frequency-test property to check calibration on m41txx To: Giulio Benetti Cc: Alessandro Zummo , Alexandre Belloni , Mark Rutland , "open list:REAL TIME CLOCK (RTC) SUBSYSTEM" , devicetree@vger.kernel.org, "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 8, 2018 at 9:56 AM, Giulio Benetti wrote: > On m41txx you can enable open-drain OUT pin to check if calibration is ok. > Enabling OUT pin with frequency-test bool property, OUT pin will tick > 512 times faster than 1s tick base. > > Enable FT bit on CONTROL register if calibration is active. A DT is (or should be) a pretty static thing, so I don't think this belongs. A kernel command line option (via module params) or a sysfs/debugfs file would make more sense IMO. Rob