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 S1752062AbbFFD3R (ORCPT <rfc822;w@1wt.eu>);
	Fri, 5 Jun 2015 23:29:17 -0400
Received: from mail-ig0-f175.google.com ([209.85.213.175]:34470 "EHLO
	mail-ig0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1751168AbbFFD3J (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Fri, 5 Jun 2015 23:29:09 -0400
MIME-Version: 1.0
X-Originating-IP: [109.186.38.88]
In-Reply-To: <557235C1.3020001@codeaurora.org>
References: <1430500026-47990-1-git-send-email-lina.iyer@linaro.org>
 <CAK=WgbYK24aTSmoSZGXDRq2GOBn6296Xa3zPZP0ycNGOtfHRxg@mail.gmail.com>
 <20150511144608.GB16124@linaro.org> <CAK=Wgbae_zXhzt9fL=YD6J9eeA8Xcgut_pBm52DNC5BE2kWCVg@mail.gmail.com>
 <20150518150302.GA23206@linaro.org> <CAK=Wgba0BVZLTJb7SYTX_NJhd46DkW-w8uHSyWsRg=xqK7jArw@mail.gmail.com>
 <20150526203634.GL23206@linaro.org> <CAK=WgbbX5dZ7=WzMr3xGVVP1vBPj_aboLnPOZZsHGi+o-Y2_Cg@mail.gmail.com>
 <557235C1.3020001@codeaurora.org>
From: Ohad Ben-Cohen <ohad@wizery.com>
Date: Sat, 6 Jun 2015 06:28:48 +0300
Message-ID: <CAK=WgbYSev_y45Gh3oJ+1xNPdvvRy=gpa=iSTgPydNodPeh3sQ@mail.gmail.com>
Subject: Re: [PATCH RFC] hwspinlock: Don't take software spinlock before hwspinlock
To: Jeffrey Hugo <jhugo@codeaurora.org>
Cc: Lina Iyer <lina.iyer@linaro.org>, "Anna, Suman" <s-anna@ti.com>,
        Bjorn Andersson <Bjorn.Andersson@sonymobile.com>,
        Andy Gross <agross@codeaurora.org>,
        "linux-arm-msm@vger.kernel.org" <linux-arm-msm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Kumar Gala <galak@codeaurora.org>
Content-Type: text/plain; charset=UTF-8
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Sat, Jun 6, 2015 at 2:50 AM, Jeffrey Hugo <jhugo@codeaurora.org> wrote:
> If you still wish to scope out a capability based alternative, would you
> please provide some details about how you envision it working?  An example
> of the API, how it would be used, future usecases that might be covered by
> it, etc.  That would give us specifics we can discuss and weigh the merits
> of.

How about:
- add a 'hwcaps' member to hwspinlock_device, and define single cap
called HWL_CAP_ALLOW_RAW
- add new 'hwcaps' parameter to hwspin_lock_register
- omap_hwspinlock.c will pass NULL, qcom_hwspinlock will pass HWL_CAP_ALLOW_RAW
- hwspin_lock_register will set hwcaps accordingly
- before a lock is taken in RAW mode, the capabilities are checked
- document everything nicely

Unless I'm missing something, it should take 5 minutes or less. For
reference, feel free to check out mmc_host's caps member and its
usage.

Thanks,
Ohad.