Commits
Shawn Guo committed 081c9025f49
clk: divider: do not propagate rate change request when unnecessary If the current rate of parent clock is sufficient to provide child a requested rate with a proper divider setting, the rate change request should not be propagated. Instead, changing the divider setting is good enough to get child clock run at the requested rate. On an imx6q clock configuration illustrated below, ahb --> ipg --> ipg_per 132M 66M 66M calling clk_set_rate(ipg_per, 22M) with the current clk_divider_bestdiv() implementation will result in the rate change up to ahb level like the following, because of the unnecessary/incorrect rate change propagation. ahb --> ipg --> ipg_per 66M 22M 22M Fix the problem by trying to see if the requested rate can be achieved by simply changing the divider value, and in that case return the divider immediately from function clk_divider_bestdiv() as the best one, so that all those unnecessary rate change propagation can be saved. Reported-by: Anson Huang <b20788@freescale.com> Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>