From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiner Kallweit Subject: [PATCH v2 3/3] hwrng: meson: add clock handling to driver Date: Tue, 21 Feb 2017 21:26:20 +0100 Message-ID: <989cf7bf-b7ea-0b41-510b-6eab403f0185@gmail.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: linux-clk@vger.kernel.org, devicetree@vger.kernel.org To: Jerome Brunet , Kevin Hilman , Herbert Xu , Neil Armstrong , linux-amlogic@lists.infradead.org, linux-crypto@vger.kernel.org, Stephen Boyd , Michael Turquette Return-path: Received: from mail-wm0-f66.google.com ([74.125.82.66]:33900 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751161AbdBUU0b (ORCPT ); Tue, 21 Feb 2017 15:26:31 -0500 In-Reply-To: Sender: linux-crypto-owner@vger.kernel.org List-ID: Add handling of RNG0 clock to the driver. Signed-off-by: Heiner Kallweit --- v2: - consider that clock is optional - use managed call to clk_disable_unprepare to ensure that cleaning up is done in the right order if driver is removed --- 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 119d6984..2e23be80 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 *clk) +{ + clk_disable_unprepare(clk); +} + 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; -- 2.11.1