From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1756449Ab0JVQ4V (ORCPT <rfc822;w@1wt.eu>);
	Fri, 22 Oct 2010 12:56:21 -0400
Received: from mho-01-ewr.mailhop.org ([204.13.248.71]:62605 "EHLO
	mho-01-ewr.mailhop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1754084Ab0JVQ4T (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Fri, 22 Oct 2010 12:56:19 -0400
X-Mail-Handler: MailHop Outbound by DynDNS
X-Originating-IP: 67.188.36.105
X-Report-Abuse-To: abuse@dyndns.com (see http://www.dyndns.com/services/mailhop/outbound_abuse.html for abuse reporting information)
X-MHO-User: U2FsdGVkX1/bP0c4hMcd1swNbUQz561Q
Date: Fri, 22 Oct 2010 09:56:13 -0700
From: Tony Lindgren <tony@atomide.com>
To: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>, Balaji T K <balajitk@ti.com>,
        "Kamat, Nishant" <nskamat@ti.com>, linux-omap@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        akpm@linux-foundation.org, Greg KH <greg@kroah.com>,
        Benoit Cousson <b-cousson@ti.com>,
        Grant Likely <grant.likely@secretlab.ca>,
        Hari Kanigeri <h-kanigeri2@ti.com>, Suman Anna <s-anna@ti.com>,
        Simon Que <sque@ti.com>
Subject: Re: [PATCH 3/3] omap: add hwspinlock device
Message-ID: <20101022165612.GF9149@atomide.com>
References: <1287387875-14168-1-git-send-email-ohad@wizery.com>
 <1287387875-14168-4-git-send-email-ohad@wizery.com>
 <87r5fmxghm.fsf@deeprootsystems.com>
 <AANLkTinZ2+ocJCfUpT15Ow3J9XBa-8XWnVC3gDDJ7s-v@mail.gmail.com>
 <87bp6pviwf.fsf@deeprootsystems.com>
 <AANLkTikE1dCXW-7ScVoDgEK3sxai_TyFzstSG+zvNm2F@mail.gmail.com>
 <8739s0sobc.fsf@deeprootsystems.com>
 <AANLkTikdjtYtzhgM_=io3SFdUZq=8Xcc8n24bW=SFgTA@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <AANLkTikdjtYtzhgM_=io3SFdUZq=8Xcc8n24bW=SFgTA@mail.gmail.com>
User-Agent: Mutt/1.5.20 (2009-06-14)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

* Ohad Ben-Cohen <ohad@wizery.com> [101020 12:12]:
> On Wed, Oct 20, 2010 at 8:37 PM, Kevin Hilman
> <khilman@deeprootsystems.com> wrote:
> >> Let's take the i2c-omap for example.
> >>
> >> It sounds like it must have a predefined hwspinlock, but what if:
> >>
> >> 1. It will use omap_hwspinlock_request() to dynamically allocate a hwspinlock
> >> 2. Obviously, the hwspinlock id number must be communicated to the M3
> >> BIOS, so the i2c-omap will publish that id using a small shared memory
> >> entry that will be allocated for this sole purpose
> >> 3. we will make sure that 1+2 completes before the remote processor is
> >> taken out of reset

Guys, let's try to come up with a generic interface for this instead of
polluting the device drivers with more omap specific interfaces.

We really want to keep the drivers generic and platform independent.

Sure we still have some omap specific stuff in the drivers, like
cpu_is_omapxxxx, and omap specific dma calls, but those will be going
away.

Unless somebody has better ideas, I suggest we pass a lock function
in the platform_data to the drivers that need it, and do the omap
specific nasty stuff in the platform code.

Regards,

Tony