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 Rohár <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> --- 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 --- a/drivers/char/hw_random/omap3-rom-rng.c +++ b/drivers/char/hw_random/omap3-rom-rng.c @@ -127,7 +127,8 @@ 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; } -- 2.23.0