From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752564AbeBSK4V (ORCPT ); Mon, 19 Feb 2018 05:56:21 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:57668 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752468AbeBSK4T (ORCPT ); Mon, 19 Feb 2018 05:56:19 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Mon, 19 Feb 2018 16:26:18 +0530 From: Abhishek Sahu To: Sricharan R Cc: Andy Gross , Wolfram Sang , David Brown , linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 08/12] i2c: qup: change completion timeout according to transfer length In-Reply-To: <7dcbac1f-edaf-aecf-8e58-04d243384758@codeaurora.org> References: <1517644697-30806-1-git-send-email-absahu@codeaurora.org> <1517644697-30806-9-git-send-email-absahu@codeaurora.org> <7dcbac1f-edaf-aecf-8e58-04d243384758@codeaurora.org> Message-ID: <6a1983c0ca81afce908f622a53abd563@codeaurora.org> User-Agent: Roundcube Webmail/1.2.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018-02-16 10:18, Sricharan R wrote: > On 2/3/2018 1:28 PM, Abhishek Sahu wrote: >> Currently the completion timeout is being taken according to >> maximum transfer length which is too high if SCL is operating in >> high frequency. This patch calculates timeout on the basis of >> one-byte transfer time and uses the same for completion timeout. >> >> Signed-off-by: Abhishek Sahu >> --- >> drivers/i2c/busses/i2c-qup.c | 9 ++++++--- >> 1 file changed, 6 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/i2c/busses/i2c-qup.c >> b/drivers/i2c/busses/i2c-qup.c >> index a91fc70..6df65ea 100644 >> --- a/drivers/i2c/busses/i2c-qup.c >> +++ b/drivers/i2c/busses/i2c-qup.c >> @@ -130,8 +130,8 @@ >> #define MX_TX_RX_LEN SZ_64K >> #define MX_BLOCKS (MX_TX_RX_LEN / QUP_READ_LIMIT) >> >> -/* Max timeout in ms for 32k bytes */ >> -#define TOUT_MAX 300 >> +/* Min timeout for i2c transfers */ >> +#define TOUT_MIN 2 >> > > may be you can mention, why is this 2 ? > This 2 seconds is timeout which I am adding on the top of maximum xfer time calculated from bus speed to compensate the interrupt latency and other factors. It will make xfer timeout minimum as 2 seconds. I will update the comment to explain it in more detail. Thanks, Abhishek