From patchwork Fri Feb 22 05:42:38 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stephen Warren X-Patchwork-Id: 2174591 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork2.kernel.org (Postfix) with ESMTP id DB418DFABD for ; Fri, 22 Feb 2013 05:46:47 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1U8lPM-0001sL-0o; Fri, 22 Feb 2013 05:42:56 +0000 Received: from avon.wwwdotorg.org ([2001:470:1f0f:bd7::2]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1U8lPI-0001rV-Fy; Fri, 22 Feb 2013 05:42:54 +0000 Received: from severn.wwwdotorg.org (unknown [192.168.65.5]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by avon.wwwdotorg.org (Postfix) with ESMTPS id 2D2C16416; Thu, 21 Feb 2013 22:46:19 -0700 (MST) Received: from dart.wwwdotorg.org (c-24-9-124-73.hsd1.co.comcast.net [24.9.124.73]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by severn.wwwdotorg.org (Postfix) with ESMTPSA id 15AA9E40FD; Thu, 21 Feb 2013 22:42:48 -0700 (MST) From: Stephen Warren To: arm@kernel.org Subject: [PATCH] ARM: bcm2835: fix I2C module clock rate Date: Thu, 21 Feb 2013 22:42:38 -0700 Message-Id: <1361511758-5208-1-git-send-email-swarren@wwwdotorg.org> X-Mailer: git-send-email 1.7.10.4 X-NVConfidentiality: public X-Virus-Scanned: clamav-milter 0.96.5 at avon.wwwdotorg.org X-Virus-Status: Clean X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130222_004252_623265_736A651F X-CRM114-Status: GOOD ( 10.06 ) X-Spam-Score: -2.6 (--) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-2.6 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 SPF_PASS SPF: sender matches SPF record -0.7 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Stephen Warren X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org BCM2835-ARM-Peripherals.pdf states that the I2C module's input clock is nominally 150MHz, and that value is currently reflected in bcm2835.dtsi. However, practical measurements show that the rate is actually 250MHz, and this agrees with various downstream kernels. Switch the I2C clock's frequency to 250MHz so that the generated bus clock rate is accurate. Signed-off-by: Stephen Warren --- This is a bug-fix for 3.9. arch/arm/boot/dts/bcm2835.dtsi | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/boot/dts/bcm2835.dtsi b/arch/arm/boot/dts/bcm2835.dtsi index 4bf2a87..7e0481e 100644 --- a/arch/arm/boot/dts/bcm2835.dtsi +++ b/arch/arm/boot/dts/bcm2835.dtsi @@ -105,7 +105,7 @@ compatible = "fixed-clock"; reg = <1>; #clock-cells = <0>; - clock-frequency = <150000000>; + clock-frequency = <250000000>; }; }; };