[PATCH] hwrng: stm32: fix maybe uninitialized variable warning

From: Maxime Coquelin
Date: Thu May 26 2016 - 05:35:09 EST


This patch fixes the following warning:
drivers/char/hw_random/stm32-rng.c: In function 'stm32_rng_read':
drivers/char/hw_random/stm32-rng.c:82:19: warning: 'sr' may be used
uninitialized in this function

Reported-by: Sudip Mukherjee <sudip.mukherjee@xxxxxxxxxxxxxxx>
Suggested-by: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Daniel Thompson <daniel.thompson@xxxxxxxxxx>
Signed-off-by: Maxime Coquelin <mcoquelin.stm32@xxxxxxxxx>
---
drivers/char/hw_random/stm32-rng.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/char/hw_random/stm32-rng.c b/drivers/char/hw_random/stm32-rng.c
index 92a810648bd0..63d84e6f1891 100644
--- a/drivers/char/hw_random/stm32-rng.c
+++ b/drivers/char/hw_random/stm32-rng.c
@@ -69,8 +69,12 @@ static int stm32_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
}

/* If error detected or data not ready... */
- if (sr != RNG_SR_DRDY)
+ if (sr != RNG_SR_DRDY) {
+ if (WARN_ONCE(sr & (RNG_SR_SEIS | RNG_SR_CEIS),
+ "bad RNG status - %x\n", sr))
+ writel_relaxed(0, priv->base + RNG_SR);
break;
+ }

*(u32 *)data = readl_relaxed(priv->base + RNG_DR);

@@ -79,10 +83,6 @@ static int stm32_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
max -= sizeof(u32);
}

- if (WARN_ONCE(sr & (RNG_SR_SEIS | RNG_SR_CEIS),
- "bad RNG status - %x\n", sr))
- writel_relaxed(0, priv->base + RNG_SR);
-
pm_runtime_mark_last_busy((struct device *) priv->rng.priv);
pm_runtime_put_sync_autosuspend((struct device *) priv->rng.priv);

--
1.9.1