Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758293AbYCZUTF (ORCPT ); Wed, 26 Mar 2008 16:19:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757066AbYCZUNY (ORCPT ); Wed, 26 Mar 2008 16:13:24 -0400 Received: from smtp.nokia.com ([192.100.122.230]:59819 "EHLO mgw-mx03.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756623AbYCZUNV (ORCPT ); Wed, 26 Mar 2008 16:13:21 -0400 Message-ID: <47EAAD9A.8080809@indt.org.br> Date: Wed, 26 Mar 2008 16:10:02 -0400 From: Carlos Aguiar User-Agent: Thunderbird 1.5.0.12 (X11/20070604) MIME-Version: 1.0 To: ext Pierre Ossman CC: Tony Lindgren , linux-kernel@vger.kernel.org Subject: [PATCH 18/18] MMC: OMAP: Do not busy wait for end of command for ever References: <47DAD39C.90405@indt.org.br> <20080324132631.1e0d2125@mjolnir.drzeus.cx> In-Reply-To: <20080324132631.1e0d2125@mjolnir.drzeus.cx> X-Enigmail-Version: 0.94.0.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 26 Mar 2008 20:12:44.0843 (UTC) FILETIME=[C0CD67B0:01C88F7D] X-Nokia-AV: Clean Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1516 Lines: 43 From: Jarkko Lavinen The limit was a fixed 100k limit in the busy loop, which is not accurate. It would better to have time limit for the worst case which occurs when sending 80 cycles at 400 kHz and takes about 200 microseconds, so limit the max time spend in the busy loop for some 250 microseconds. Signed-off-by: Jarkko Lavinen --- drivers/mmc/host/omap.c | 8 +++++++- 1 files changed, 7 insertions(+), 1 deletions(-) diff --git a/drivers/mmc/host/omap.c b/drivers/mmc/host/omap.c index b28ae3b..2468e2f 100644 --- a/drivers/mmc/host/omap.c +++ b/drivers/mmc/host/omap.c @@ -1276,11 +1276,17 @@ static void mmc_omap_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) OMAP_MMC_WRITE(host, CON, dsor); slot->saved_con = dsor; if (ios->power_mode == MMC_POWER_ON) { + /* worst case at 400kHz, 80 cycles makes 200 microsecs */ + int usecs = 250; + /* Send clock cycles, poll completion */ OMAP_MMC_WRITE(host, IE, 0); OMAP_MMC_WRITE(host, STAT, 0xffff); OMAP_MMC_WRITE(host, CMD, 1 << 7); - while ((OMAP_MMC_READ(host, STAT) & 1) == 0); + while (usecs > 0 && (OMAP_MMC_READ(host, STAT) & 1) == 0) { + udelay(1); + usecs--; + } OMAP_MMC_WRITE(host, STAT, 1); } -- 1.5.3.GIT -- 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/