From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hein_Tibosch Subject: SD power-control necessary? Date: Fri, 07 Jan 2011 22:39:14 +0800 Message-ID: <4D272592.6000508@yahoo.es> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from bosmailout02.eigbox.net ([66.96.188.2]:57198 "EHLO bosmailout02.eigbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753484Ab1AGPVc (ORCPT ); Fri, 7 Jan 2011 10:21:32 -0500 Received: from bosmailscan07.eigbox.net ([10.20.15.7]) by bosmailout02.eigbox.net with esmtp (Exim) id 1PbDUx-0003Aw-Af for linux-mmc@vger.kernel.org; Fri, 07 Jan 2011 09:40:59 -0500 Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: "linux-mmc@vger.kernel.org" Hello, Maybe a stupid question, but when designing new hardware with a slot for an sd-card, how essential is it that the driver is able to power off/on the card? I would say essential, because I've seen sd-cards in a state in which they didn't respond to MMC_GO_IDLE_STATE anymore, until they were re-inserted. Can anyone shed a light on this? How could an sd-card get into such a state? Will the mmc driver fall back to mmc_rescan() after an initialized card becomes non-responsive? Thanks, Hein