[PATCH 2/2] hwrng: meson: add clock handling to driver
Heiner Kallweit
hkallweit1 at gmail.com
Sun Feb 19 12:35:52 PST 2017
Add handling of RNG0 clock to the driver.
Signed-off-by: Heiner Kallweit <hkallweit1 at gmail.com>
---
drivers/char/hw_random/meson-rng.c | 27 ++++++++++++++++++++++++++-
1 file changed, 26 insertions(+), 1 deletion(-)
diff --git a/drivers/char/hw_random/meson-rng.c b/drivers/char/hw_random/meson-rng.c
index 119d6984..1f586e48 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)
@@ -86,6 +88,7 @@ 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)
@@ -98,12 +101,33 @@ 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))
+ return PTR_ERR(data->core_clk);
+
+ ret = clk_prepare_enable(data->core_clk);
+ if (ret)
+ return ret;
+
data->rng.name = pdev->name;
data->rng.read = meson_rng_read;
platform_set_drvdata(pdev, data);
- return devm_hwrng_register(dev, &data->rng);
+ ret = devm_hwrng_register(dev, &data->rng);
+ if (ret)
+ clk_disable_unprepare(data->core_clk);
+
+ return ret;
+}
+
+static int meson_rng_remove(struct platform_device *pdev)
+{
+ struct meson_rng_data *data = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(data->core_clk);
+
+ return 0;
}
static const struct of_device_id meson_rng_of_match[] = {
@@ -114,6 +138,7 @@ MODULE_DEVICE_TABLE(of, meson_rng_of_match);
static struct platform_driver meson_rng_driver = {
.probe = meson_rng_probe,
+ .remove = meson_rng_remove,
.driver = {
.name = "meson-rng",
.of_match_table = meson_rng_of_match,
--
2.11.1
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