Subject: Re: [PATCH 01/33] clk_ops: change round_rate() to return unsigned
 long
To: Mikko Perttunen <cyndis@kapsi.fi>, mturquette@baylibre.com,
        sboyd@codeaurora.org, linux-kernel@vger.kernel.org,
        linux-clk@vger.kernel.org
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        linux-mips@linux-mips.org, linux-rpi-kernel@lists.infradead.org,
        patches@opensource.cirrus.com, uclinux-h8-devel@lists.sourceforge.jp,
        linux-amlogic@lists.infradead.org, linux-arm-msm@vger.kernel.org,
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        linux-mediatek@lists.infradead.org, freedreno@lists.freedesktop.org,
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From: "Bryan O'Donoghue" <pure.logic@nexus-software.ie>
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Date: Sun, 31 Dec 2017 13:40:07 +0000
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On 30/12/17 16:36, Mikko Perttunen wrote:
> FWIW, we had this problem some years ago with the Tegra CPU clock - then 
> it was determined that a simpler solution was to have the determine_rate 
> callback support unsigned long rates - so clock drivers that need to 
> return rates higher than 2^31 can instead implement the determine_rate 
> callback. That is what's currently implemented.
> 
> Mikko

Granted we could work around it but, having both zero and less than zero 
indicate error means you can't support larger than LONG_MAX which is I 
think worth fixing.

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bod