[PATCH AUTOSEL 4.9 18/91] hwrng: omap3-rom - Call clk_disable_unprepare() on exit only if not idled

[Sasha Levin]

From: Tony Lindgren <tony@xxxxxxxxxxx>

[ Upstream commit eaecce12f5f0d2c35d278e41e1bc4522393861ab ]

When unloading omap3-rom-rng, we'll get the following:

WARNING: CPU: 0 PID: 100 at drivers/clk/clk.c:948 clk_core_disable

This is because the clock may be already disabled by omap3_rom_rng_idle().
Let's fix the issue by checking for rng_idle on exit.

Cc: Aaro Koskinen <aaro.koskinen@xxxxxx>
Cc: Adam Ford <aford173@xxxxxxxxx>
Cc: Pali RohÃr <pali.rohar@xxxxxxxxx>
Cc: Sebastian Reichel <sre@xxxxxxxxxx>
Cc: Tero Kristo <t-kristo@xxxxxx>
Fixes: 1c6b7c2108bd ("hwrng: OMAP3 ROM Random Number Generator support")
Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/char/hw_random/omap3-rom-rng.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/char/hw_random/omap3-rom-rng.c b/drivers/char/hw_random/omap3-rom-rng.c
index 37a58d78aab31..3324a7f4bee37 100644
--- a/drivers/char/hw_random/omap3-rom-rng.c
+++ b/drivers/char/hw_random/omap3-rom-rng.c
@@ -114,7 +114,8 @@ static int omap3_rom_rng_remove(struct platform_device *pdev)
 {
 	cancel_delayed_work_sync(&idle_work);
 	hwrng_unregister(&omap3_rom_rng_ops);
-	clk_disable_unprepare(rng_clk);
+	if (!rng_idle)
+		clk_disable_unprepare(rng_clk);
 	return 0;
 }
 
-- 
2.20.1