From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934261AbdKBBGH (ORCPT ); Wed, 1 Nov 2017 21:06:07 -0400 Received: from mail-pf0-f194.google.com ([209.85.192.194]:47552 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933886AbdKBBEd (ORCPT ); Wed, 1 Nov 2017 21:04:33 -0400 X-Google-Smtp-Source: ABhQp+SXO6lc1q7isnsRbLMdJBX1npslPeDzueceDQmiXIeDHYjtUDAnnlMZaFgLR1hBfsJCohcuLA== From: Florian Fainelli To: linux-kernel@vger.kernel.org Cc: Florian Fainelli , Matt Mackall , Herbert Xu , Rob Herring , Mark Rutland , Ray Jui , Scott Branden , bcm-kernel-feedback-list@broadcom.com (maintainer:BROADCOM BCM281XX/BCM11XXX/BCM216XX ARM ARCHITE...), Eric Anholt , Stefan Wahren , PrasannaKumar Muralidharan , Russell King , Krzysztof Kozlowski , Harald Freudenberger , Sean Wang , Martin Kaiser , Steffen Trumtrar , linux-crypto@vger.kernel.org (open list:HARDWARE RANDOM NUMBER GENERATOR CORE), devicetree@vger.kernel.org (open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS), linux-rpi-kernel@lists.infradead.org (moderated list:BROADCOM BCM2835 ARM ARCHITECTURE), linux-arm-kernel@lists.infradead.org (moderated list:BROADCOM BCM2835 ARM ARCHITECTURE) Subject: [PATCH 07/12] hwrng: bcm2835-rng: Manage an optional clock Date: Wed, 1 Nov 2017 18:04:03 -0700 Message-Id: <20171102010408.27736-8-f.fainelli@gmail.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20171102010408.27736-1-f.fainelli@gmail.com> References: <20171102010408.27736-1-f.fainelli@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org One of the last steps before bcm63xx-rng can be eliminated is to manage a clock during hwrng::init and hwrng::cleanup, so fetch it in the probe function, and manage it during these two steps when valid. Signed-off-by: Florian Fainelli --- drivers/char/hw_random/bcm2835-rng.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c index ed20e0b6b7ae..35928efb52e7 100644 --- a/drivers/char/hw_random/bcm2835-rng.c +++ b/drivers/char/hw_random/bcm2835-rng.c @@ -15,6 +15,7 @@ #include #include #include +#include #define RNG_CTRL 0x0 #define RNG_STATUS 0x4 @@ -33,6 +34,7 @@ struct bcm2835_rng_priv { struct hwrng rng; void __iomem *base; bool mask_interrupts; + struct clk *clk; }; static inline struct bcm2835_rng_priv *to_rng_priv(struct hwrng *rng) @@ -67,6 +69,11 @@ static int bcm2835_rng_init(struct hwrng *rng) { struct bcm2835_rng_priv *priv = to_rng_priv(rng); u32 val; + int ret; + + ret = clk_prepare_enable(priv->clk); + if (ret) + return ret; if (priv->mask_interrupts) { /* mask the interrupt */ @@ -88,6 +95,8 @@ static void bcm2835_rng_cleanup(struct hwrng *rng) /* disable rng hardware */ __raw_writel(0, priv->base + RNG_CTRL); + + clk_disable_unprepare(priv->clk); } struct bcm2835_rng_of_data { @@ -130,6 +139,11 @@ static int bcm2835_rng_probe(struct platform_device *pdev) return PTR_ERR(priv->base); } + /* Clock is optional on most platforms */ + priv->clk = devm_clk_get(dev, NULL); + if (IS_ERR(priv->clk)) + priv->clk = NULL; + priv->rng.name = "bcm2835-rng"; priv->rng.init = bcm2835_rng_init; priv->rng.read = bcm2835_rng_read; -- 2.9.3