From 529571ed8d8cc293c112a2061f130a3f8d458954 Mon Sep 17 00:00:00 2001 From: "lionel.debieve@st.com" Date: Thu, 15 Feb 2018 14:03:10 +0100 Subject: [PATCH] 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 Signed-off-by: Herbert Xu --- drivers/char/hw_random/stm32-rng.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) 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), -- 2.30.2