From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752741AbaIRXCX (ORCPT ); Thu, 18 Sep 2014 19:02:23 -0400 Received: from smtp.codeaurora.org ([198.145.11.231]:42153 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751401AbaIRXCW convert rfc822-to-8bit (ORCPT ); Thu, 18 Sep 2014 19:02:22 -0400 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) Subject: Re: [PATCH] pinctrl: qcom: use restart_notifier mechanism for ps_hold From: Kumar Gala In-Reply-To: <20140918224904.GD3749@joshc.qualcomm.com> Date: Thu, 18 Sep 2014 16:02:19 -0700 Cc: Bjorn Andersson , Linus Walleij , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, Pramod Gurav , Guenter Roeck Content-Transfer-Encoding: 8BIT Message-Id: <9CD0FD1C-E8EA-4585-9837-070199BCC26D@codeaurora.org> References: <1411079579-10172-1-git-send-email-joshc@codeaurora.org> <11F1E440-6BD4-46F1-A399-4334FBA2C3B6@codeaurora.org> <20140918224904.GD3749@joshc.qualcomm.com> To: Josh Cartwright X-Mailer: Apple Mail (2.1878.6) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sep 18, 2014, at 3:49 PM, Josh Cartwright wrote: > On Thu, Sep 18, 2014 at 03:47:20PM -0700, Kumar Gala wrote: >> On Sep 18, 2014, at 3:32 PM, Josh Cartwright wrote: >> >>> By converting to the restart_notifier mechanism for restart, we allow >>> for other mechanisms, like the watchdog, to be used for restart in the >>> case where PS_HOLD has failed to reset the chip. >>> >>> Choose priority 128, as according to documentation, this mechanism "is >>> sufficient to restart the entire system?. >> >> Will we use a higher priority for watchdog? or how would we fail over to watchdog? > > The registered restart handlers are called in (descending) priority > order. This driver registers as 128, but conceivably there could be > some super-board-specific restart mechanism that can register itself as > higher priority than this and it will be attempted first. > > If PS_HOLD doesn't work, the lower priority restart handlers will > continue to be called, including the watchdog, which is registering with > the lowest priority (0). Cool, thanks. - k -- Employee of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation