From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: Re: [PATCH 2/2] OMAP: HSMMC: Fix response type for busy after response Date: Tue, 13 Jan 2009 16:19:48 +0200 Message-ID: <496CA304.9000802@nokia.com> References: <20090113133827.29474.92645.sendpatchset@ahunter-laptop> <20090113133841.29474.15852.sendpatchset@ahunter-laptop> <20090113144952.3f8cbec8@mjolnir.drzeus.cx> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.nokia.com ([192.100.122.233]:46886 "EHLO mgw-mx06.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753111AbZAMOII (ORCPT ); Tue, 13 Jan 2009 09:08:08 -0500 In-Reply-To: <20090113144952.3f8cbec8@mjolnir.drzeus.cx> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Pierre Ossman Cc: Tony Lindgren , Russell King - ARM Linux , lkml , linux-omap Mailing List , "Lavinen Jarkko (Nokia-M/Helsinki)" , Madhusudhan Chikkature Pierre Ossman wrote: > On Tue, 13 Jan 2009 15:38:41 +0200 > Adrian Hunter wrote: > >> This also fixes the hidden problem that the controller >> was turning off the clock to the card while the card >> was busy - the clock was then switched on for the >> duration of each Send Status command used for polling, >> which is why writes did not lock up altogether. >> i.e. really dysfunctional. > > Does the driver only keep the clock running as long as there is an > ongoing request? That kind of policy should really be handled in the > core where we have more information and can control it better. E.g. some > cards need the clock to finish up internal housekeeping so we need to > delay things for those. > > Rgds Unfortunately it seems to be something the controller does by itself, beyond the control of the driver. Added Jarkko Lavinen and Madhusudhan Chikkature to CC, maybe they can correct me. If it obeys the standard, it should give an additional 8 clock cycles.