From 7a794a73d4440cb257f541cc29630c7560266cf7 Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Wed, 22 Feb 2017 08:02:31 +0100 Subject: [PATCH] hwrng: meson - add clock handling to driver Add handling of RNG0 clock to the driver. Signed-off-by: Heiner Kallweit Signed-off-by: Herbert Xu --- drivers/char/hw_random/meson-rng.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) 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 #include #include +#include #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;