Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753397Ab2FLRHk (ORCPT ); Tue, 12 Jun 2012 13:07:40 -0400 Received: from na3sys009aog101.obsmtp.com ([74.125.149.67]:52286 "EHLO na3sys009aog101.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751623Ab2FLRHh (ORCPT ); Tue, 12 Jun 2012 13:07:37 -0400 From: Kevin Hilman To: "ABRAHAM\, KISHON VIJAY" Cc: Arnd Bergmann , "Cousson\, Benoit" , Paul Walmsley , tony@atomide.com, linux@arm.linux.org.uk, gregkh@linuxfoundation.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, balbi@ti.com Subject: Re: [RFC PATCH 0/5] omap: add ocp2scp as a misc driver Organization: Texas Instruments, Inc. References: <1338375394-16268-1-git-send-email-kishon@ti.com> <201205310922.18550.arnd@arndb.de> <201205312046.14823.arnd@arndb.de> Date: Tue, 12 Jun 2012 10:07:35 -0700 In-Reply-To: (KISHON VIJAY ABRAHAM's message of "Wed, 6 Jun 2012 20:40:50 +0530") Message-ID: <87fwa01mso.fsf@ti.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2263 Lines: 52 "ABRAHAM, KISHON VIJAY" writes: > Hi Kevin, Benoit, Paul, > > On Fri, Jun 1, 2012 at 2:16 AM, Arnd Bergmann wrote: >> On Thursday 31 May 2012, ABRAHAM, KISHON VIJAY wrote: >>> > I would mark the multiplexed device compatible with "simple-bus", which >>> > results in the child devices automatically getting added. >>> >>> hmm.. ocp2scp has a sysconfig register and it also has a module mode >>> by which it can be enabled/disabled. I was making use of pm_runtime >>> API's to control these registers (Apart from creating child devices, >>> the driver also has a call to pm_runtime_enable). >> >> I see. >> >>> I'm not sure if with >>> "simple-bus" we'll be able to do those. I have to check on that. >> >> How about making it compatible with both "simple-bus" and something >> that handles the pm_runtime requirements? >> >> I don't understand enough of what needs to be done for pm_runtime >> across a lot of devices, but I'd hope that it should be possible >> to do that in a generic way based on the device definition. > > Is there already exists a generic way for handling pm_runtime > requirements (as simple as doing a pm_runtime_enable on a device). As you've discovered, the runtime PM core handles the parent/child relationships already. > So the actual problem is we have ocp2scp as parent and usb2phy and > usb3phy as the child device. ocp2scp has the sysconfig register and it > can be controlled using module mode bit (both of this can be > controlled by pm_runtime). Whenever usb controller(dwc3/musb) wants to > enable a phy, it calls an exported API in usb2/usb3 phy to enable it. > These API's have pm_runtime_get_sync on usb2/usb3 device which in-turn > calls pm_runtime_get_sync of ocp2scp because of parent->child > relationship (For this both usb2/usb3 phy and ocp2scp devices should > have called pm_runtime_enable). All I'm trying is to find a place to > have pm_runtime_enable for ocp2scp. Maybe I'm not following, but why can't it be in the driver? Kevin -- 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/