linux-kernel - [PATCH 2/2] hwrng: iproc-rng200: Move enable/disable in separate function

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Date:   Mon, 14 Dec 2020 17:04:54 +0100
From:   matthias.bgg@...nel.org
To:     mpm@...enic.com, herbert@...dor.apana.org.au, rjui@...adcom.com,
        sbranden@...adcom.com, f.fainelli@...il.com
Cc:     linux-kernel@...r.kernel.org, Julia.Lawall@...ia.fr,
        bcm-kernel-feedback-list@...adcom.com,
        linux-arm-kernel@...ts.infradead.org, nsaenzjulienne@...e.de,
        linux-crypto@...r.kernel.org, Matthias Brugger <mbrugger@...e.com>
Subject: [PATCH 2/2] hwrng: iproc-rng200: Move enable/disable in separate function

From: Matthias Brugger <mbrugger@...e.com>

We are calling the same code for enable and disable the block in various
parts of the driver. Put that code into a new function to reduce code
duplication.

Signed-off-by: Matthias Brugger <mbrugger@...e.com>

---

 drivers/char/hw_random/iproc-rng200.c | 37 ++++++++++++---------------
 1 file changed, 17 insertions(+), 20 deletions(-)

diff --git a/drivers/char/hw_random/iproc-rng200.c b/drivers/char/hw_random/iproc-rng200.c
index e106ce3c0146..3367b26085e8 100644
--- a/drivers/char/hw_random/iproc-rng200.c
+++ b/drivers/char/hw_random/iproc-rng200.c
@@ -53,15 +53,26 @@ struct iproc_rng200_dev {
 
 #define to_rng_priv(rng)	container_of(rng, struct iproc_rng200_dev, rng)
 
-static void iproc_rng200_restart(void __iomem *rng_base)
+static void iproc_rng200_enable(void __iomem *rng_base, bool enable)
 {
 	uint32_t val;
 
-	/* Disable RBG */
 	val = ioread32(rng_base + RNG_CTRL_OFFSET);
 	val &= ~RNG_CTRL_RNG_RBGEN_MASK;
-	val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;
+
+	if (enable)
+		val |= RNG_CTRL_RNG_RBGEN_ENABLE;
+	else
+		val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;
+
 	iowrite32(val, rng_base + RNG_CTRL_OFFSET);
+}
+
+static void iproc_rng200_restart(void __iomem *rng_base)
+{
+	uint32_t val;
+
+	iproc_rng200_enable(rng_base, false);
 
 	/* Clear all interrupt status */
 	iowrite32(0xFFFFFFFFUL, rng_base + RNG_INT_STATUS_OFFSET);
@@ -83,11 +94,7 @@ static void iproc_rng200_restart(void __iomem *rng_base)
 	val &= ~RBG_SOFT_RESET;
 	iowrite32(val, rng_base + RBG_SOFT_RESET_OFFSET);
 
-	/* Enable RBG */
-	val = ioread32(rng_base + RNG_CTRL_OFFSET);
-	val &= ~RNG_CTRL_RNG_RBGEN_MASK;
-	val |= RNG_CTRL_RNG_RBGEN_ENABLE;
-	iowrite32(val, rng_base + RNG_CTRL_OFFSET);
+	iproc_rng200_enable(rng_base, true);
 }
 
 static int iproc_rng200_read(struct hwrng *rng, void *buf, size_t max,
@@ -154,13 +161,8 @@ static int iproc_rng200_read(struct hwrng *rng, void *buf, size_t max,
 static int iproc_rng200_init(struct hwrng *rng)
 {
 	struct iproc_rng200_dev *priv = to_rng_priv(rng);
-	uint32_t val;
 
-	/* Setup RNG. */
-	val = ioread32(priv->base + RNG_CTRL_OFFSET);
-	val &= ~RNG_CTRL_RNG_RBGEN_MASK;
-	val |= RNG_CTRL_RNG_RBGEN_ENABLE;
-	iowrite32(val, priv->base + RNG_CTRL_OFFSET);
+	iproc_rng200_enable(priv->base, true);
 
 	return 0;
 }
@@ -168,13 +170,8 @@ static int iproc_rng200_init(struct hwrng *rng)
 static void iproc_rng200_cleanup(struct hwrng *rng)
 {
 	struct iproc_rng200_dev *priv = to_rng_priv(rng);
-	uint32_t val;
 
-	/* Disable RNG hardware */
-	val = ioread32(priv->base + RNG_CTRL_OFFSET);
-	val &= ~RNG_CTRL_RNG_RBGEN_MASK;
-	val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;
-	iowrite32(val, priv->base + RNG_CTRL_OFFSET);
+	iproc_rng200_enable(priv->base, false);
 }
 
 static int iproc_rng200_probe(struct platform_device *pdev)
-- 
2.29.2