From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 07 Jul 2016 22:27:38 +0900 From: Andi Shyti To: Krzysztof Kozlowski Cc: Chanwoo Choi , Jaehoon Chung , Sylwester Nawrocki , Tomasz Figa , Michael Turquette , Stephen Boyd , Kukjin Kim , linux-samsung-soc@vger.kernel.org, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Andi Shyti Subject: Re: [PATCH v4 1/2] clk: exynos5433: do not use CLK_IGNORE_UNUSED for SPI clocks Message-id: <20160707132738.GI23620@samsunx.samsung> References: <1467893637-12573-1-git-send-email-andi.shyti@samsung.com> <1467893637-12573-2-git-send-email-andi.shyti@samsung.com> <577E4F1C.8070004@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii In-reply-to: <577E4F1C.8070004@samsung.com> List-ID: Hi Krzysztof, > > The CLK_IGNORE_UNUSED flag has to be avoided whenever possible. > > Use the CLK_IS_CRITICAL flag instead for critical SPI1 clocks, > > which enables the clock line during boot time. > > I don't agree. Both flags should be avoided. Clk is critical does not > solve the problem. It is just a better workaround for lack of proper > clock consumers. > > The IOCLK is not a critical clock. It can be disabled (e.g. when SoC is > used on a board without any SPI device connected). As we discussed offline there is no driver which is requesting this clock. We cannot ask to the spi driver to handle three clocks because the exynos5433 has its own peculiarities. If we want this on the spi driver's side, we need to add a new compatible and check it everytime. To me it looks uglier than just keep it alive. Thanks, Andi