hwrng: timeriomem - Fix cooldown period calculation

[ Upstream commit e145f55 ]

Ensure cooldown period tolerance of 1% is actually accounted for.

Fixes: ca3bff7 ("hwrng: timeriomem - Improve performance...")
Signed-off-by: Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: janweinstock

drivers/char/hw_random/timeriomem-rng.c

@@ -69,7 +69,7 @@ static int timeriomem_rng_read(struct hwrng *hwrng, void *data,
 		 */
 		if (retval > 0)
 			usleep_range(period_us,
-					period_us + min(1, period_us / 100));
+					period_us + max(1, period_us / 100));
 
 		*(u32 *)data = readl(priv->io_base);
 		retval += sizeof(u32);