Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757525Ab3JOG4a (ORCPT ); Tue, 15 Oct 2013 02:56:30 -0400 Received: from mail-oa0-f43.google.com ([209.85.219.43]:59241 "EHLO mail-oa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752087Ab3JOG42 (ORCPT ); Tue, 15 Oct 2013 02:56:28 -0400 MIME-Version: 1.0 In-Reply-To: <1381818232-12542-1-git-send-email-ch.naveen@samsung.com> References: <1381490814-20890-1-git-send-email-ch.naveen@samsung.com> <1381818232-12542-1-git-send-email-ch.naveen@samsung.com> Date: Tue, 15 Oct 2013 15:56:27 +0900 X-Google-Sender-Auth: hUIGqsGLfwJ2_0xRY9dfH2Mm_2Y Message-ID: Subject: Re: [PATCH v2] i2c: s3c2410: dont need CPU_FREQ transitions for exynos series From: Kyungmin Park To: Naveen Krishna Chatradhi Cc: linux-i2c@vger.kernel.org, t.figa@samsung.com, sjg@chromium.org, linux-kernel@vger.kernel.org, linux-samsung-soc@vger.kernel.org, wsa@the-dreams.de, ben-linux@fluff.org, grant.likely@secretlab.ca, broonie@kernel.org, dianders@chromium.org, cpgs@samsung.com Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2208 Lines: 58 On Tue, Oct 15, 2013 at 3:23 PM, Naveen Krishna Chatradhi wrote: > For Exynos4 and Exynos5 SoCs from Samsung the i2c clock is based > on a fixed 66 MHz peripheral clock, and therefore is completely > independent of the cpu frequency. > Thus, registering for a CPU freq notifier is very wasteful. > > This patch modifes the code such that, i2c bus registers to > cpu_freq_transition only if CONFIG_CPU_FREQ_S3C24XX is enabled. > > This change should save a bunch of cpufreq transitions calls > which does not apply to exynos SoCs. > > Signed-off-by: Naveen Krishna Chatradhi Acked-by: Kyungmin Park > --- > Changes since v1: > Use CONFIG_CPU_FREQ_S3C24XX instead of (CONFIG_CPU_FREQ & !CONFIG_EXYNOS) > As commented by Tomasz > > drivers/i2c/busses/i2c-s3c2410.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c > index cab1c91..97f14f7 100644 > --- a/drivers/i2c/busses/i2c-s3c2410.c > +++ b/drivers/i2c/busses/i2c-s3c2410.c > @@ -123,7 +123,7 @@ struct s3c24xx_i2c { > struct s3c2410_platform_i2c *pdata; > int gpios[2]; > struct pinctrl *pctrl; > -#ifdef CONFIG_CPU_FREQ > +#if defined(CONFIG_CPU_FREQ_S3C24XX) > struct notifier_block freq_transition; > #endif > }; > @@ -843,7 +843,7 @@ static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got) > return 0; > } > > -#ifdef CONFIG_CPU_FREQ > +#if defined(CONFIG_CPU_FREQ_S3C24XX) > > #define freq_to_i2c(_n) container_of(_n, struct s3c24xx_i2c, freq_transition) > > -- > 1.7.10.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/