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authorlionel.debieve@st.com <lionel.debieve@st.com>2018-02-15 14:03:10 +0100
committerHerbert Xu <herbert@gondor.apana.org.au>2018-03-03 00:03:09 +0800
commit529571ed8d8cc293c112a2061f130a3f8d458954 (patch)
tree635118ba548288f472dae78e3841f8db35698496 /drivers/char/hw_random
parent695788fd1b41938e86b9fba9670f751599836b2d (diff)
downloadlinux-529571ed8d8cc293c112a2061f130a3f8d458954.tar.bz2
hwrng: stm32 - allow disable clock error detection
Add a new property that allow to disable the clock error detection which is required when the clock source selected is out of specification (which is not mandatory). Signed-off-by: Lionel Debieve <lionel.debieve@st.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/char/hw_random')
-rw-r--r--drivers/char/hw_random/stm32-rng.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/drivers/char/hw_random/stm32-rng.c b/drivers/char/hw_random/stm32-rng.c
index 83c695938a2d..709a8d061be3 100644
--- a/drivers/char/hw_random/stm32-rng.c
+++ b/drivers/char/hw_random/stm32-rng.c
@@ -26,6 +26,7 @@
#define RNG_CR 0x00
#define RNG_CR_RNGEN BIT(2)
+#define RNG_CR_CED BIT(5)
#define RNG_SR 0x04
#define RNG_SR_SEIS BIT(6)
@@ -48,6 +49,7 @@ struct stm32_rng_private {
void __iomem *base;
struct clk *clk;
struct reset_control *rst;
+ bool ced;
};
static int stm32_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
@@ -101,7 +103,11 @@ static int stm32_rng_init(struct hwrng *rng)
if (err)
return err;
- writel_relaxed(RNG_CR_RNGEN, priv->base + RNG_CR);
+ if (priv->ced)
+ writel_relaxed(RNG_CR_RNGEN, priv->base + RNG_CR);
+ else
+ writel_relaxed(RNG_CR_RNGEN | RNG_CR_CED,
+ priv->base + RNG_CR);
/* clear error indicators */
writel_relaxed(0, priv->base + RNG_SR);
@@ -149,6 +155,8 @@ static int stm32_rng_probe(struct platform_device *ofdev)
reset_control_deassert(priv->rst);
}
+ priv->ced = of_property_read_bool(np, "clock-error-detect");
+
dev_set_drvdata(dev, priv);
priv->rng.name = dev_driver_string(dev),