From mboxrd@z Thu Jan 1 00:00:00 1970 From: jeremy.kerr@canonical.com (Jeremy Kerr) Date: Mon, 07 Feb 2011 14:07:57 +0800 Subject: [RFC, PATCH 3/3] clk: add warnings for incorrect enable/prepare semantics In-Reply-To: <201102011711.31258.jeremy.kerr@canonical.com> Message-ID: <1297058877.800990.238556019385.3.gpush@pororo> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org This change adds warnings to check for: 1) enabling a clock that hasn't been prepared; and 2) unpreparing a clock that is still enabled While the correctness can't be guaranteed, these warnings should cover most situations. Signed-off-by: Jeremy Kerr --- drivers/clk/clk.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 51dbd33..2369959 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -35,6 +35,8 @@ void clk_unprepare(struct clk *clk) if (!clk->ops->unprepare) return; + WARN_ON(clk->enable_count); + mutex_lock(&clk->prepare_lock); if (--clk->prepare_count == 0) clk->ops->unprepare(clk); @@ -50,6 +52,8 @@ int clk_enable(struct clk *clk) if (!clk->ops->enable) return 0; + WARN_ON(clk->ops->prepare && clk->prepare_count); + spin_lock(&clk->enable_lock); if (!clk->enable_count) ret = clk->ops->enable(clk);