From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ohad Ben-Cohen <ohad@wizery.com>
Subject: Re: MMC runtime PM patches break libertas probe
Date: Fri, 10 Jun 2011 07:28:41 +0300
Message-ID: <BANLkTinDe6fOavZZ+1c1OKS7XMf_J5YhaA@mail.gmail.com>
References: <AANLkTim+Ez8FonyZDu42u4NX-KKV0YS_J-Ya-zT-Gf9q@mail.gmail.com>
 <AANLkTinEes6Er6-WW_t8esjazrLWZ0Z7jvYJDSZL9PNG@mail.gmail.com>
 <AANLkTinJ2K2cz9PSdyNoNGUS8GWfLpqRBH2C3XjO5vjO@mail.gmail.com>
 <AANLkTi=VAU=9Q+Ga7yQyu3aL7gV0vbzymQ-2uJAg1jf8@mail.gmail.com>
 <AANLkTi=QT6_zyddRz=3f6GDx-RVoiROOumhegm8pFuHU@mail.gmail.com>
 <AANLkTimfp0pPqpO03-R4yBsADQ27RLQ_PxLTfBAMfPGk@mail.gmail.com>
 <AANLkTi=gFmq47Xq+CxnU18aHyhcaF78WrWYDhga4Xf2X@mail.gmail.com>
 <AANLkTimqFBBsDCCDNOq22fuqjw7pezizZ9At+1ucGZ-j@mail.gmail.com>
 <AANLkTi=RP0i5cWO4AogGJx-sQ+17YKuiptQWi0ypYVnA@mail.gmail.com>
 <AANLkTiktD13-UC8=gwWhp9oR9_vGcM98VpRQ9i0CQg_-@mail.gmail.com>
 <AANLkTi=8Xd1xTfFvAJkicR_89JOu4P2uwyoMHvXCBKv8@mail.gmail.com>
 <AANLkTi=cPURFAitedD=mjkNiD_=ZCjakkMN6z7ecqv6k@mail.gmail.com>
 <BANLkTikpciJnTudOeSLM_O7AAD4GGkbbOw@mail.gmail.com> <BANLkTikQC+u5yyU+YBAZ5JpFDRFHrHNOoA@mail.gmail.com>
 <BANLkTi=kqnnGf3ezS=cSXCcHpmK3JxwXtg@mail.gmail.com> <BANLkTi=o6Hgb=icinjmZqVx09dx+cp-enw@mail.gmail.com>
 <BANLkTimuLrCd3oHeWOC73scuQ6ydvuwpvw@mail.gmail.com> <BANLkTimmSu33PTDn9ybOSbAfObPe4C-rZA@mail.gmail.com>
 <477F20668A386D41ADCC57781B1F704307FD0BF3B1@SC-VEXCH1.marvell.com>
 <BANLkTi=nz8c9P2qi9FWE+QU0XzSFddUAhA@mail.gmail.com> <477F20668A386D41ADCC57781B1F704307FD0BF3BE@SC-VEXCH1.marvell.com>
 <BANLkTi=qR7bbsnzsCpV=b2C4Ha5Hdb94gQ@mail.gmail.com> <BANLkTimZ+Emm6GrTztEaGnjRu92Pam13mQ@mail.gmail.com>
 <BANLkTi=KjP9sUD0+QjDrJro0JXW4A+zOKg@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Return-path: <linux-mmc-owner@vger.kernel.org>
Received: from mail-wy0-f174.google.com ([74.125.82.174]:64126 "EHLO
	mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1751371Ab1FJE3C (ORCPT
	<rfc822;linux-mmc@vger.kernel.org>); Fri, 10 Jun 2011 00:29:02 -0400
Received: by wya21 with SMTP id 21so1585012wya.19
        for <linux-mmc@vger.kernel.org>; Thu, 09 Jun 2011 21:29:01 -0700 (PDT)
In-Reply-To: <BANLkTi=KjP9sUD0+QjDrJro0JXW4A+zOKg@mail.gmail.com>
Sender: linux-mmc-owner@vger.kernel.org
List-Id: linux-mmc@vger.kernel.org
To: zhangfei gao <zhangfei.gao@gmail.com>
Cc: Bing Zhao <bzhao@marvell.com>, Daniel Drake <dsd@laptop.org>, "linux-mmc@vger.kernel.org" <linux-mmc@vger.kernel.org>, Mike Rapoport <mike@compulab.co.il>, Zhangfei Gao <zgao6@marvell.com>

Hi Zhangfei,

On Fri, Jun 10, 2011 at 5:02 AM, zhangfei gao <zhangfei.gao@gmail.com> wrote:
> Here is answer got from the sd8686 maintainer.
>
> For 8686, the SDIO state machine can only handle init sequence (CMD5,
> 5, 3, 7) from host once. If host sends another init sequence, it will
> not be able to handle CMD5 and causes the SDIO block to hang. Chips
> that are newer than 8686 will be able to handle multiple init sequence
> from host.

Thanks for the reply !

> So yes, for 8686, an IO reset is needed before host can send a new set
> of init sequence.

But if we're powering down and up the device first, then the init
sequence is considered the first one, and then we don't need an IO
reset, right ? That was what we wondered about.

Thanks,
Ohad.