[RFC] opp: Fixup release of clock when using set/put clkname

From: Rajendra Nayak
Date: Tue Apr 14 2020 - 03:15:38 EST


Fixup dev_pm_opp_put_clkname() to check for a valid clock pointer
before it does a clk_put, since its likely that
_opp_table_kref_release() has already done a clk_put. Also fixup
_opp_table_kref_release() to set the clock pointer to ERR_PTR(-EINVAL)
after its done doing a clk_put so dev_pm_opp_put_clkname() can then
catch it.

Signed-off-by: Rajendra Nayak <rnayak@xxxxxxxxxxxxxx>
---
drivers/opp/core.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index e4f01e7..6d064a8 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -1061,8 +1061,10 @@ static void _opp_table_kref_release(struct kref *kref)
_of_clear_opp_table(opp_table);

/* Release clk */
- if (!IS_ERR(opp_table->clk))
+ if (!IS_ERR(opp_table->clk)) {
clk_put(opp_table->clk);
+ opp_table->clk = ERR_PTR(-EINVAL);
+ }

WARN_ON(!list_empty(&opp_table->opp_list));

@@ -1744,8 +1746,10 @@ void dev_pm_opp_put_clkname(struct opp_table *opp_table)
/* Make sure there are no concurrent readers while updating opp_table */
WARN_ON(!list_empty(&opp_table->opp_list));

- clk_put(opp_table->clk);
- opp_table->clk = ERR_PTR(-EINVAL);
+ if (!IS_ERR(opp_table->clk)) {
+ clk_put(opp_table->clk);
+ opp_table->clk = ERR_PTR(-EINVAL);
+ }

dev_pm_opp_put_opp_table(opp_table);
}
--
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