From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Kroah-Hartman Subject: Re: [PATCH v7 1/2] drivers: base: add support for registering notifier about deferred probe Date: Thu, 14 Apr 2016 14:51:39 -0700 Message-ID: <20160414215139.GA11535@kroah.com> References: <1460540160-18762-1-git-send-email-m.szyprowski@samsung.com> <1460540160-18762-2-git-send-email-m.szyprowski@samsung.com> <20160413141254.GB12749@kroah.com> <570F4886.20203@samsung.com> <20160414211745.GA27692@kroah.com> <20160414213322.GW19428@n2100.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail.linuxfoundation.org ([140.211.169.12]:41633 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751500AbcDNVvk (ORCPT ); Thu, 14 Apr 2016 17:51:40 -0400 Content-Disposition: inline In-Reply-To: <20160414213322.GW19428@n2100.arm.linux.org.uk> Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: Russell King - ARM Linux Cc: Marek Szyprowski , linux-samsung-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Ulf Hansson , Krzysztof Kozlowski , Bartlomiej Zolnierkiewicz On Thu, Apr 14, 2016 at 10:33:22PM +0100, Russell King - ARM Linux wrote: > The problem that's being addressed here is that there's no way at the > moment to know when the drivers on a different bus (namely the platform > bus) have probed and are providing the clock and power domain resources > necessary to be able to read these identifying values. > > I guess if you don't like a notifier, the other alternative is to > setup a delayed workqueue and have the workqueue repeatedly attempt > to register the devices until they all succeed. That's not > particularly nice, because we'd be wasting CPU cycles running > that workqueue for no reason until all the devices get registered. I like that idea, it handles the issue of this crazy hardware where it belongs, in that bus subsystem :) thanks, greg k-h From mboxrd@z Thu Jan 1 00:00:00 1970 From: gregkh@linuxfoundation.org (Greg Kroah-Hartman) Date: Thu, 14 Apr 2016 14:51:39 -0700 Subject: [PATCH v7 1/2] drivers: base: add support for registering notifier about deferred probe In-Reply-To: <20160414213322.GW19428@n2100.arm.linux.org.uk> References: <1460540160-18762-1-git-send-email-m.szyprowski@samsung.com> <1460540160-18762-2-git-send-email-m.szyprowski@samsung.com> <20160413141254.GB12749@kroah.com> <570F4886.20203@samsung.com> <20160414211745.GA27692@kroah.com> <20160414213322.GW19428@n2100.arm.linux.org.uk> Message-ID: <20160414215139.GA11535@kroah.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Apr 14, 2016 at 10:33:22PM +0100, Russell King - ARM Linux wrote: > The problem that's being addressed here is that there's no way at the > moment to know when the drivers on a different bus (namely the platform > bus) have probed and are providing the clock and power domain resources > necessary to be able to read these identifying values. > > I guess if you don't like a notifier, the other alternative is to > setup a delayed workqueue and have the workqueue repeatedly attempt > to register the devices until they all succeed. That's not > particularly nice, because we'd be wasting CPU cycles running > that workqueue for no reason until all the devices get registered. I like that idea, it handles the issue of this crazy hardware where it belongs, in that bus subsystem :) thanks, greg k-h