Hi Mike,
On 08/07/2015 09:09 PM, Michael Turquette wrote:
This patch adds prepare and enable reference counts for the per-user
handles that clock consumers have for a clock node. This patch warns if
an imbalance occurs while trying to disable or unprepare a clock and
aborts, leaving the hardware unaffected.
Signed-off-by: Michael Turquette <mturque...@baylibre.com>
---
drivers/clk/clk.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 898052e..72feee9 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -84,6 +84,8 @@ struct clk {
unsigned long min_rate;
unsigned long max_rate;
struct hlist_node clks_node;
+ unsigned int enable_count;
+ unsigned int prepare_count;
};
/*** locking ***/
@@ -600,6 +602,9 @@ void clk_unprepare(struct clk *clk)
return;
clk_prepare_lock();
+ if (WARN_ON(clk->prepare_count == 0))
Isn't clk_prepare_unlock()call missing here before return?
+ return;
+ clk->prepare_count--;
clk_core_unprepare(clk->core);
clk_prepare_unlock();
}
@@ -657,6 +662,7 @@ int clk_prepare(struct clk *clk)
return 0;
clk_prepare_lock();
+ clk->prepare_count++;
ret = clk_core_prepare(clk->core);
clk_prepare_unlock();
@@ -707,6 +713,9 @@ void clk_disable(struct clk *clk)
return;
flags = clk_enable_lock();
+ if (WARN_ON(clk->enable_count == 0))
Ditto.
+ return;
+ clk->enable_count--;
clk_core_disable(clk->core);
clk_enable_unlock(flags);
}
Regards,
Maxime
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