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From: Ohad Ben-Cohen <ohad@wizery.com>
Date: Fri, 14 Nov 2014 22:05:07 +0200
Message-ID: <CAK=WgbYEQPwPH-i_kfF8-h6uOH9q4rcT1+W0smG3e=chDg833Q@mail.gmail.com>
Subject: Re: [PATCHv6 4/5] hwspinlock/core: add common OF helpers
To: Suman Anna <s-anna@ti.com>
Cc: Mark Rutland <mark.rutland@arm.com>, Kumar Gala <galak@codeaurora.org>,
        Tony Lindgren <tony@atomide.com>,
        Josh Cartwright <joshc@codeaurora.org>,
        Bjorn Andersson <bjorn@kryo.se>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-omap@vger.kernel.org" <linux-omap@vger.kernel.org>,
        linux-arm <linux-arm-kernel@lists.infradead.org>
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On Fri, Nov 14, 2014 at 7:09 PM, Suman Anna <s-anna@ti.com> wrote:
>> It seems to me that hwspin_lock_request_specific failures should be
>> used by clients to defer their probing. Why wouldn't such a simple
>> solution work?

> Because the API always returns NULL on failures and there is no way for
> the clients to figure out if the lock id passed is invalid or the bank
> containing the lock is not registered.

It seems to me this may always be the case - lock ids may be wrong and
there's no way to fully validate them.

Let's start with the simpler approach where
hwspin_lock_request_specific failures are used by clients to defer
their probing.

If a real use case will require changes we can always do that later,
though it seems to me the only gain by changing this API is to catch a
small subset of fatal DT mistakes which will anyway be caught very
early in the development.

Thanks,
Ohad.