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Date:   Sat, 24 Aug 2019 02:32:29 +0200
From:   Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= 
        <u.kleine-koenig@pengutronix.de>
To:     Sam Shih <sam.shih@mediatek.com>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        Ryder Lee <ryder.lee@mediatek.com>,
        John Crispin <john@phrozen.org>, linux-pwm@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mediatek@lists.infradead.org
Subject: Re: [PATCH v5 03/13] pwm: mediatek: add a property "clock-frequency"
Message-ID: <20190824003229.7uch4m54vrxlt7uj@pengutronix.de>
References: <1566457123-20791-1-git-send-email-sam.shih@mediatek.com>
 <1566457123-20791-4-git-send-email-sam.shih@mediatek.com>
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Hello Sam,

On Thu, Aug 22, 2019 at 02:58:33PM +0800, Sam Shih wrote:
> This fix mt7628 pwm during configure from userspace. The SoC
> is legacy MIPS and has no complex clock tree. This patch add property
> clock-frequency to the SoC specific data and legacy MIPS SoC need to
> configure it in DT. This property is use for period calculation.
> 
> We will improve this fix by droping has-clks attribute and using
> clock-frequency to do the same thing in a new patch.
> 
> Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
> Signed-off-by: Sam Shih <sam.shih@mediatek.com>

I wonder if instead the platform could provide some dummy and optional
clocks.

You could add a fixed-clock for the clk that is used to determine the
clock rate and switch to devm_clk_get_optional for the others.

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-K?nig            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |