From mboxrd@z Thu Jan 1 00:00:00 1970 From: francesco.virlinzi@st.com (Francesco VIRLINZI) Date: Tue, 10 Nov 2009 15:00:59 +0100 Subject: [Proposal] [PATCH] generic clock framework Message-ID: <4AF9721B.4070203@st.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi all I'm Francesco and I work in STMicroelectronics In the last ELC-E_2009 I spoke on a generic clock framework I'm working on (see http://tree.celinuxforum.org/CelfPubWiki/ELCEurope2009Presentations?action=AttachFile&do=view&target=ELC_E_2009_Generic_Clock_Framework.pdf). I wrote the gcf to manage both clocks the platform_devices during a clock operation. The main features are: - it's integrated in the LDM - it tracks the clock-to-clock relationship - it tracks the clock-to-device relationship - it has sysfs interface - - the user can navigate the clock tree under /sys/clocks/... - it uses the linux API () with some extra functions (to register/unregister a clock and other utility functions as clk_for_each()) - it involves the platform_device and the platform_driver in the clock propagation. - - basically each clock operation is managed as a transaction which evolves step by step. - - all the clock rates are evaluated (before the clk operation is actually done) - - each platform_device can check (before the clk operation is actually done) the clk environment it will have at the end of clock operation and if required it can reject the operation. - - each clock operation is actually executed only if all the platform_devices accept the operation it-self Moreover a common clock framework could be used to avoid a lot of duplicated and/or similar code just a grep of 'EXPORT_SYMBOL\(clk_enable' under arch/arm finds 22 entries. The patch is based on a 2.6.30 kernel also if it has a preliminary integration with the PM_RUNTIME support. It works on our st40 (an sh4 cpu based system) no test/porting was done on any ARM platform. It would be mainly a starting point for a discussion and I'm available to extend/fix/share it. Regards Francesco -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- An embedded and charset-unspecified text was scrubbed... Name: 0001-generic-clock-framework.patch URL: