From c56cebbe83dde1c93599eb29d85d5c889d7a00cf Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Mon, 14 Mar 2016 09:07:13 +0900 Subject: hwrng: exynos - Fix unbalanced PM runtime put on timeout error path commit f1925d78d7b710a1179828d53e918295f5f5d222 upstream. 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") Signed-off-by: Krzysztof Kozlowski Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- drivers/char/hw_random/exynos-rng.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'drivers/char/hw_random') diff --git a/drivers/char/hw_random/exynos-rng.c b/drivers/char/hw_random/exynos-rng.c index 30cf4623184f..aa30af5f0f2b 100644 --- a/drivers/char/hw_random/exynos-rng.c +++ b/drivers/char/hw_random/exynos-rng.c @@ -89,6 +89,7 @@ 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); @@ -97,17 +98,20 @@ 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) -- cgit v1.2.3