[ARM] omap: clk_set_parent: deny changing parent if clock is enabled

[pandora-kernel.git] / arch / arm / plat-omap / clock.c

diff --git a/arch/arm/plat-omap/clock.c b/arch/arm/plat-omap/clock.c
index 08baa18..2e06145 100644 (file)
--- a/arch/arm/plat-omap/clock.c
+++ b/arch/arm/plat-omap/clock.c
@@ -144,13 +144,16 @@ int clk_set_parent(struct clk *clk, struct clk *parent)
                return ret;
 
        spin_lock_irqsave(&clockfw_lock, flags);
-       if (arch_clock->clk_set_parent)
-               ret = arch_clock->clk_set_parent(clk, parent);
-       if (ret == 0) {
-               if (clk->recalc)
-                       clk->rate = clk->recalc(clk);
-               propagate_rate(clk);
-       }
+       if (clk->usecount == 0) {
+               if (arch_clock->clk_set_parent)
+                       ret = arch_clock->clk_set_parent(clk, parent);
+               if (ret == 0) {
+                       if (clk->recalc)
+                               clk->rate = clk->recalc(clk);
+                       propagate_rate(clk);
+               }
+       } else
+               ret = -EBUSY;
        spin_unlock_irqrestore(&clockfw_lock, flags);
 
        return ret;