[PATCH 4/4] hwrng: bcm2835: Read as much data as available
From: Yendapally Reddy Dhananjaya Reddy <hidden>
Date: 2016-05-23 16:21:46
Also in:
linux-crypto, linux-devicetree, lkml
Subsystem:
hardware random number generator core, the rest · Maintainers:
Olivia Mackall, Herbert Xu, Linus Torvalds
Read the requested number of data from the fifo Signed-off-by: Yendapally Reddy Dhananjaya Reddy <redacted> --- drivers/char/hw_random/bcm2835-rng.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c
index b1e8b78..9bbdc07 100644
--- a/drivers/char/hw_random/bcm2835-rng.c
+++ b/drivers/char/hw_random/bcm2835-rng.c@@ -43,6 +43,8 @@ static int bcm2835_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait) { void __iomem *rng_base = (void __iomem *)rng->priv; + u32 max_words = max/sizeof(u32); + u32 num_words, count; while ((__raw_readl(rng_base + RNG_STATUS) >> 24) == 0) { if (!wait)
@@ -50,8 +52,14 @@ static int bcm2835_rng_read(struct hwrng *rng, void *buf, size_t max, cpu_relax(); } - *(u32 *)buf = __raw_readl(rng_base + RNG_DATA); - return sizeof(u32); + num_words = (readl(rng_base + RNG_STATUS) >> 24); + if (num_words > max_words) + num_words = max_words; + + for (count = 0; count < num_words; count++) + ((u32 *)buf)[count] = readl(rng_base + RNG_DATA); + + return (num_words * sizeof(u32)); } static struct hwrng bcm2835_rng_ops = {
--
2.1.0