summaryrefslogtreecommitdiff
path: root/drivers/char/hw_random/meson-rng.c
diff options
context:
space:
mode:
authorHeiner Kallweit <hkallweit1@gmail.com>2017-02-22 08:02:31 +0100
committerHerbert Xu <herbert@gondor.apana.org.au>2017-03-16 17:58:49 +0800
commit7a794a73d4440cb257f541cc29630c7560266cf7 (patch)
tree387c3faffd8150fe49124aa3afc3399168bc22b1 /drivers/char/hw_random/meson-rng.c
parent1b3f6d148692ef3c3c96af1647083ff38d429e46 (diff)
hwrng: meson - add clock handling to driver
Add handling of RNG0 clock to the driver. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/char/hw_random/meson-rng.c')
-rw-r--r--drivers/char/hw_random/meson-rng.c22
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/char/hw_random/meson-rng.c b/drivers/char/hw_random/meson-rng.c
index 119d698439ae..2e23be802a62 100644
--- a/drivers/char/hw_random/meson-rng.c
+++ b/drivers/char/hw_random/meson-rng.c
@@ -62,6 +62,7 @@
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/of.h>
+#include <linux/clk.h>
#define RNG_DATA 0x00
@@ -69,6 +70,7 @@ struct meson_rng_data {
void __iomem *base;
struct platform_device *pdev;
struct hwrng rng;
+ struct clk *core_clk;
};
static int meson_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
@@ -81,11 +83,17 @@ static int meson_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
return sizeof(u32);
}
+static void meson_rng_clk_disable(void *data)
+{
+ clk_disable_unprepare(data);
+}
+
static int meson_rng_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct meson_rng_data *data;
struct resource *res;
+ int ret;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
@@ -98,6 +106,20 @@ static int meson_rng_probe(struct platform_device *pdev)
if (IS_ERR(data->base))
return PTR_ERR(data->base);
+ data->core_clk = devm_clk_get(dev, "core");
+ if (IS_ERR(data->core_clk))
+ data->core_clk = NULL;
+
+ if (data->core_clk) {
+ ret = clk_prepare_enable(data->core_clk);
+ if (ret)
+ return ret;
+ ret = devm_add_action_or_reset(dev, meson_rng_clk_disable,
+ data->core_clk);
+ if (ret)
+ return ret;
+ }
+
data->rng.name = pdev->name;
data->rng.read = meson_rng_read;