Using orphan clocks can introduce strange behaviour as they don't have rate information at all and also of course don't track
This v2/v3 takes into account suggestions from Stephen Boyd to not try to walk the clock tree at runtime but instead keep track of orphan states on clock tree changes and making it mandatory for everybody from the start as orphaned clocks should not be used at all. This fixes an issue on most rk3288 platforms, where some soc-clocks are supplied by a 32khz clock from an external i2c-chip which often is only probed later in the boot process and maybe even after the drivers using these soc-clocks like the tsadc temperature sensor. In this case the driver using the clock should of course defer probing until the clock is actually usable. As this changes the behaviour for orphan clocks, it would of course benefit from more testing than on my Rockchip boards. To keep the recipent-list reasonable and not spam to much I selected one (the topmost) from the get_maintainer output of each drivers/clk entry. Hopefully some will provide Tested-by-tags :-) Thanks Heiko changes since v2: adapt to comments from Stephen Boyd - rename to clk_core_update_orphan_status - use bools instead of 0/1 for the status - remove redundant check in clk_is_orphan changes since v1: - track orphan status on clock tree changes instead of walking the tree on clk_get operations - make get-deferals mandatory for everybody Cc: Boris Brezillon <[email protected]> Cc: Alex Elder <[email protected]> Cc: Alexandre Belloni <[email protected]> Cc: Stephen Warren <[email protected]> Cc: Max Filippov <[email protected]> Cc: [email protected] Cc: Zhangfei Gao <[email protected]> Cc: Santosh Shilimkar <[email protected]> Cc: Chao Xie <[email protected]> Cc: Jason Cooper <[email protected]> Cc: Stefan Wahren <[email protected]> Cc: Andrew Bresticker <[email protected]> Cc: Robert Jarzmik <[email protected]> Cc: Georgi Djakov <[email protected]> Cc: Sylwester Nawrocki <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Barry Song <[email protected]> Cc: Dinh Nguyen <[email protected]> Cc: Viresh Kumar <[email protected]> Cc: Gabriel FERNANDEZ <[email protected]> Cc: [email protected] Cc: Peter De Schrijver <[email protected]> Cc: Tero Kristo <[email protected]> Cc: Ulf Hansson <[email protected]> Cc: Pawel Moll <[email protected]> Cc: Michal Simek <[email protected]> Heiko Stuebner (2): clk: track the orphan status of clocks and their children clk: prevent orphan clocks from being used drivers/clk/clk.c | 46 +++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 43 insertions(+), 3 deletions(-) -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
