Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754688AbaDKDJ4 (ORCPT ); Thu, 10 Apr 2014 23:09:56 -0400 Received: from mail-yk0-f170.google.com ([209.85.160.170]:63635 "EHLO mail-yk0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753190AbaDKDJz (ORCPT ); Thu, 10 Apr 2014 23:09:55 -0400 MIME-Version: 1.0 In-Reply-To: <20140410173616.GC6518@sirena.org.uk> References: <1397134229-2380-1-git-send-email-harinik@xilinx.com> <20140410173616.GC6518@sirena.org.uk> Date: Fri, 11 Apr 2014 08:39:54 +0530 Message-ID: Subject: Re: [PATCH] spi: core: Increase timeout value From: Harini Katakam To: Mark Brown Cc: linux-spi@vger.kernel.org, "linux-kernel@vger.kernel.org" , michals@xilinx.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 Hi Mark, On Thu, Apr 10, 2014 at 11:06 PM, Mark Brown wrote: > On Thu, Apr 10, 2014 at 06:20:29PM +0530, Harini Katakam wrote: > >> Considering acceptable latencies, this timeout can be set to a large >> value >= 1*HZ typically. > >> This patch adds a tolerance of 2000 msec in the core accordingly. > > That's too much, it's 2 seconds which gets to be incredibly painful when > trying to debug problems - if you're sitting there waiting for a driver > to time out some operations (and it may be more than one of them) so you > can look at the diagnostics it can be quite aggrivating. That's why the > delays are related to the expected runtime for the operation. Something > like double the expected runtime plus something in the 100ms or so range > perhaps? > OK. > Ideally we'd use the actual speed the device set rather than the > requested one too, that'd help. How would you propose to do that - driver should write back actual speed set to xfer->speed_hz? Regards, Harini -- 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/