From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kalyan Kinthada Subject: Re: [PATCH] dt-bindings: i2c: Add armada-38x i2c binding Date: Sun, 24 Sep 2017 21:44:21 +0000 Message-ID: <1506289460890.34765@alliedtelesis.co.nz> References: <20170922020429.20941-1-kalyan.kinthada@alliedtelesis.co.nz>,<87377fmbpw.fsf@free-electrons.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Received: from gate2.alliedtelesis.co.nz ([202.36.163.20]:44780 "EHLO gate2.alliedtelesis.co.nz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752881AbdIXVo1 (ORCPT ); Sun, 24 Sep 2017 17:44:27 -0400 In-Reply-To: <87377fmbpw.fsf@free-electrons.com> Content-Language: en-NZ Sender: linux-i2c-owner@vger.kernel.org List-Id: linux-i2c@vger.kernel.org To: Gregory CLEMENT Cc: "devicetree@vger.kernel.org" , "wsa@the-dreams.de" , "robh+dt@kernel.org" , "pawel.moll@arm.com" , "mark.rutland@arm.com" , "ijc+devicetree@hellion.org.uk" , "galak@codeaurora.org" , "linux-i2c@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Chris Packham Hi Gregory,=0A= =0A= I got this information from Armada-38x functional errata document.=0A= =0A= I can add the "marvell,mv78230-i2c" compatible string to the appropriate d= evice tree files =0A= but the i2c-mv64xxx driver enables an additional feature (offload i2c tran= sactions)=0A= based on the compatible string "marvell,mv78230-i2c".=0A= =0A= I am not sure if this feature (offload i2c transactions) should be enabled = for Armada-38x devices.=0A= That is the reason I felt for the need of a new compatible string specifica= lly for Armada-38x SoCs.=0A= =0A= Thanks,=0A= Kalyan=0A= ________________________________________=0A= From: Gregory CLEMENT =0A= Sent: Friday, 22 September 2017 7:30 p.m.=0A= To: Kalyan Kinthada=0A= Cc: devicetree@vger.kernel.org; wsa@the-dreams.de; robh+dt@kernel.org; pawe= l.moll@arm.com; mark.rutland@arm.com; ijc+devicetree@hellion.org.uk; galak@= codeaurora.org; linux-i2c@vger.kernel.org; linux-kernel@vger.kernel.org; Ch= ris Packham=0A= Subject: Re: [PATCH] dt-bindings: i2c: Add armada-38x i2c binding=0A= =0A= Hi Kalyan,=0A= =0A= On ven., sept. 22 2017, Kalyan Kinthada wrote:=0A= =0A= > All armada-38x variants(380, 385, 388) SoCs have an issue=0A= > in i2c controller which violates the i2c repeated start timing.=0A= =0A= =0A= Did you had an issue with one of the SoC ?=0A= If yes what was your setting ?=0A= On my side I never managed to have this sort of issue on Armada 38x.=0A= =0A= >=0A= > This errata is fixed in the i2c-mv64xxx driver but enabled=0A= > only for devices with compatible string "marvell,mv78230-i2c".=0A= =0A= In this case why not just adding the "marvell,mv78230-i2c" as compatible=0A= string in the appropriate device tree files ?=0A= =0A= Gregory=0A= =0A= >=0A= > This patch introduces a new compatible string=0A= > "marvell,armada-38x-i2c" for the i2c controller on armada-38x SoCs=0A= > so that the workaound is enabled.=0A= =0A= =0A= >=0A= > Signed-off-by: Kalyan Kinthada =0A= > ---=0A= > Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt | 1 +=0A= > 1 file changed, 1 insertion(+)=0A= >=0A= > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt b/Docu= mentation/devicetree/bindings/i2c/i2c-mv64xxx.txt=0A= > index 5c30026921..fc100b6bdb 100644=0A= > --- a/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt=0A= > +++ b/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt=0A= > @@ -14,6 +14,7 @@ Required properties :=0A= > very rare, initial version of the SoC which=0A= > had broken offload support. Linux=0A= > auto-detects this and sets it appropriately.=0A= > + - "marvell,armada-38x-i2c"=0A= > - interrupts : The interrupt number=0A= >=0A= > Optional properties :=0A= > --=0A= > 2.14.1=0A= >=0A= =0A= --=0A= Gregory Clement, Free Electrons=0A= Kernel, drivers, real-time and embedded Linux=0A= development, consulting, training and support.=0A= http://free-electrons.com=0A=