From f1925d78d7b710a1179828d53e918295f5f5d222 Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Mon, 14 Mar 2016 09:07:13 +0900 Subject: [PATCH] hwrng: exynos - Fix unbalanced PM runtime put on timeout error path In case of timeout during read operation, the exit path lacked PM runtime put. This could lead to unbalanced runtime PM usage counter thus leaving the device in an active state. Fixes: d7fd6075a205 ("hwrng: exynos - Add timeout for waiting on init done") Cc: # v4.4+ Signed-off-by: Krzysztof Kozlowski Signed-off-by: Herbert Xu --- drivers/char/hw_random/exynos-rng.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/char/hw_random/exynos-rng.c b/drivers/char/hw_random/exynos-rng.c index d1fd21e..38b80f8 100644 --- a/drivers/char/hw_random/exynos-rng.c +++ b/drivers/char/hw_random/exynos-rng.c @@ -90,6 +90,7 @@ static int exynos_read(struct hwrng *rng, void *buf, struct exynos_rng, rng); u32 *data = buf; int retry = 100; + int ret = 4; pm_runtime_get_sync(exynos_rng->dev); @@ -98,17 +99,20 @@ static int exynos_read(struct hwrng *rng, void *buf, while (!(exynos_rng_readl(exynos_rng, EXYNOS_PRNG_STATUS_OFFSET) & PRNG_DONE) && --retry) cpu_relax(); - if (!retry) - return -ETIMEDOUT; + if (!retry) { + ret = -ETIMEDOUT; + goto out; + } exynos_rng_writel(exynos_rng, PRNG_DONE, EXYNOS_PRNG_STATUS_OFFSET); *data = exynos_rng_readl(exynos_rng, EXYNOS_PRNG_OUT1_OFFSET); +out: pm_runtime_mark_last_busy(exynos_rng->dev); pm_runtime_put_sync_autosuspend(exynos_rng->dev); - return 4; + return ret; } static int exynos_rng_probe(struct platform_device *pdev) -- 2.7.4