Hello, This short patch set aims to fix issues in the common clock framework WRT support of the clock suppliers as loadable modules. The thread [1] might be a good summary and pre-requisiste reading on what this patch series is trying to achieve. The first patch adds common implementation of the __clk_get(), __clk_put() helpers for the common clock framework. Currently these functions are empty and the modules that registered clocks are prone to removal and leaving invalid clock references. The second patch adds implementation of the clk_unregister() function and is based on patch [2]. I have some doubts whether we need to be taking reference on a module in clk_get() _and_ use kref to keep track of references to a clock. Taking reference on a module only seems insufficient, since a clock supplier driver can be unbound from its device through sysfs, even if the module stays in place. We could be doing only reference counting on the clock, but then there are issues as Russell clearly explained in [1]. It is not obvious what to do with a clock when it has consumers and its supplier driver is being deinitialized/unloaded [3]. IMHO clock suppliers should be normally prevented from being removed when resources they provide are in use, otherwise it all may get a bit hairy. Thanks, Sylwester [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2013-July/183302.html [2] http://www.spinics.net/lists/arm-kernel/msg247548.html [3] http://lists.infradead.org/pipermail/linux-arm-kernel/2013-July/183292.html Sylwester Nawrocki (2): clk: add common __clk_get(), __clk_put() implementations clk: implement clk_unregister arch/arm/include/asm/clkdev.h | 2 + arch/blackfin/include/asm/clkdev.h | 2 + arch/mips/include/asm/clkdev.h | 2 + arch/sh/include/asm/clkdev.h | 2 + drivers/clk/clk.c | 147 +++++++++++++++++++++++++++++++++++- include/linux/clk-private.h | 5 ++ include/linux/clkdev.h | 5 ++ 7 files changed, 162 insertions(+), 3 deletions(-) -- 1.7.9.5
