Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756726Ab1CIINp (ORCPT ); Wed, 9 Mar 2011 03:13:45 -0500 Received: from mga02.intel.com ([134.134.136.20]:6492 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752478Ab1CIINn (ORCPT ); Wed, 9 Mar 2011 03:13:43 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.62,289,1297065600"; d="scan'208";a="718071919" Date: Wed, 9 Mar 2011 16:06:09 +0800 From: Chuanxiao Dong To: linux-mmc@vger.kernel.org, cjb@laptop.org Cc: kmpark@infradead.org, prakity@marvell.com, jh80.chung@samsung.com, w.sang@pengutronix.de, linux-kernel@vger.kernel.org Subject: [PATCH]mmc: set timeout for SDHCI host before sending busy cmds Message-ID: <20110309080609.GA23207@intel.com> Reply-To: Chuanxiao Dong MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2132 Lines: 55 Hi all, From the previous discussion, I do not think we have got a clear conclusion about using maximum timeout value. At least we know from Jae hoon Chung using 0xE for every case is not a good. So I want to suggest only use 0xE for busy command. I personally preferred below implementation, which is similar with a RFC patch submitted by Jae hoon Chung, but only without adding a new quirk. I think sdhci_calc_timeout should be left for data transfer since at least we can get a warning if 0xE is not enough for host to use. And if the host controller and the card have no bugs, then the calculated timeout should be safe. Left the old implementation unchanged is also compatible with all existed host controllers and cards. But for busy command, we are not clear about how long is safe enough for waiting and there is also no function to do the calculation for them. So preferred just using 0xE. Below the patch and comment: Set the timeout control register for SDHCI host when send some commands which need busy signal. Use the maximum timeout value 0xE will be safe. Signed-off-by: Chuanxiao Dong --- drivers/mmc/host/sdhci.c | 9 ++++++++- 1 files changed, 8 insertions(+), 1 deletions(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 99c372e..8306323 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -659,8 +659,15 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_data *data) WARN_ON(host->data); - if (data == NULL) + if (data == NULL) { + /* + * set the timeout to be maximum value for commands those with + * busy signal + */ + if (host->cmd->flags & MMC_RSP_BUSY) + sdhci_writeb(host, 0xE, SDHCI_TIMEOUT_CONTROL); return; + } /* Sanity checks */ BUG_ON(data->blksz * data->blocks > 524288); -- 1.6.6.1 -- 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/