From aa87aa343f2cd236b5eccd643abd4df918ed5c4f Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Tue, 12 May 2009 05:51:05 +0900 Subject: sh: clkfwk: Improve the generic clk_set_parent() implementation. This causes the generic clk_set_parent() implementation to be a bit more intelligent. A clk_reparent() is added to move the clock over to the new parent's sibling list, which then allows the generic rate propagation code to succeed. This also becomes a nop if the new and old parents are unchanged. Signed-off-by: Paul Mundt --- arch/sh/kernel/cpu/clock.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'arch/sh/kernel/cpu/clock.c') diff --git a/arch/sh/kernel/cpu/clock.c b/arch/sh/kernel/cpu/clock.c index e027fe5..e3d1de8 100644 --- a/arch/sh/kernel/cpu/clock.c +++ b/arch/sh/kernel/cpu/clock.c @@ -81,6 +81,19 @@ unsigned long followparent_recalc(struct clk *clk) return clk->parent->rate; } +int clk_reparent(struct clk *child, struct clk *parent) +{ + list_del_init(&child->sibling); + if (parent) + list_add(&child->sibling, &parent->children); + child->parent = parent; + + /* now do the debugfs renaming to reattach the child + to the proper parent */ + + return 0; +} + /* Propagate rate to children */ void propagate_rate(struct clk *tclk) { @@ -288,12 +301,19 @@ int clk_set_parent(struct clk *clk, struct clk *parent) if (!parent || !clk) return ret; + if (clk->parent == parent) + return 0; spin_lock_irqsave(&clock_lock, flags); if (clk->usecount == 0) { if (clk->ops->set_parent) ret = clk->ops->set_parent(clk, parent); + else + ret = clk_reparent(clk, parent); + if (ret == 0) { + pr_debug("clock: set parent of %s to %s (new rate %ld)\n", + clk->name, clk->parent->name, clk->rate); if (clk->ops->recalc) clk->rate = clk->ops->recalc(clk); propagate_rate(clk); -- cgit v1.1