/**
* omap2_clk_disable - disable a clock, if the system is not using it
* @clk: struct clk * to disable
*
* Decrements the usecount on struct clk @clk. If there are no users
* left, call the clkops-specific clock disable function to disable it
* in hardware. If the clock is part of a clockdomain (which they all
* should be), request that the clockdomain be disabled. (It too has
* a usecount, and so will not be disabled in the hardware until it no
* longer has any users.) If the clock has a parent clock (most of
* them do), then call ourselves, recursing on the parent clock. This
* can cause an entire branch of the clock tree to be powered off by
* simply disabling one clock. Intended to be called with the clockfw_lock
* spinlock held. No return value.
*/
void omap2_clk_disable(struct clk *clk)
{
if (clk->usecount == 0) {
WARN(1, "clock: %s: omap2_clk_disable() called, but usecount "
"already 0?", clk->name);
return;
}
pr_debug("clock: %s: decrementing usecount\n", clk->name);
clk->usecount--;
if (clk->usecount > 0)
return;
pr_debug("clock: %s: disabling in hardware\n", clk->name);
if (clk->ops && clk->ops->disable) {
trace_clock_disable(clk->name, 0, smp_processor_id());
clk->ops->disable(clk);
}
if (clk->clkdm)
clkdm_clk_disable(clk->clkdm, clk);
if (clk->parent)
omap2_clk_disable(clk->parent);
}
void clk_disable(struct clk *clk)
{
unsigned long flags;
if (IS_ERR_OR_NULL(clk))
return;
spin_lock_irqsave(&clk->lock, flags);
if (WARN(!clk->warned && !clk->prepare_count,
"%s: Never called prepare or calling disable "
"after unprepare\n",
clk->dbg_name))
clk->warned = true;
if (WARN(clk->count == 0, "%s is unbalanced", clk->dbg_name))
goto out;
if (clk->count == 1) {
struct clk *parent = clk_get_parent(clk);
trace_clock_disable(clk->dbg_name, 0, smp_processor_id());
if (clk->ops->disable)
clk->ops->disable(clk);
unvote_rate_vdd(clk, clk->rate);
clk_disable(clk->depends);
clk_disable(parent);
}
clk->count--;
out:
spin_unlock_irqrestore(&clk->lock, flags);
}
