From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934220AbZFMBC5 (ORCPT ); Fri, 12 Jun 2009 21:02:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762311AbZFMBCk (ORCPT ); Fri, 12 Jun 2009 21:02:40 -0400 Received: from mail-ew0-f210.google.com ([209.85.219.210]:48424 "EHLO mail-ew0-f210.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1763094AbZFMBCj (ORCPT ); Fri, 12 Jun 2009 21:02:39 -0400 MIME-Version: 1.0 Date: Fri, 12 Jun 2009 18:02:41 -0700 X-Google-Sender-Auth: a4637cc6644bd213 Message-ID: Subject: [PATCH 3/6] Unified AVR32/AT91 MCI Driver Reset Patch From: Rob Emanuele To: Haavard Skinnemoen Cc: Andrew Victor , Nicolas Ferre , linux-arm-kernel@lists.arm.linux.org.uk, linux-kernel@vger.kernel.org, drzeus-mmc@drzeus.cx Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch adds the compile time configuration option for the atmel-mci driver to reset the Atmel MCI controller before every command. This is sometimes needed for the Atmel controller / board to function properly. In the case of the at91sam9g20-ek this is needed. Please read the whole set, try it out, and comment. Thank you, Rob Emanuele --- drivers/mmc/host/Kconfig | 10 ++++++++++ drivers/mmc/host/atmel-mci.c | 11 ++++++++++- 2 files changed, 20 insertions(+), 1 deletions(-) diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig index 6e2f52b..9e24029 100644 --- a/drivers/mmc/host/Kconfig +++ b/drivers/mmc/host/Kconfig @@ -150,6 +150,16 @@ config MMC_ATMELMCI endchoice +config MMC_ATMELMCI_ALWAYS_RESET + bool "Reset before every request. Sometimes needed for buggy chips." + depends on MMC_ATMELMCI + help + There are reports that some buggy controllers work better + with a reset before every command. This may improve your + controller's reliability. + + If unsure, say N. + config MMC_ATMELMCI_DMA bool "Atmel MCI DMA support (EXPERIMENTAL)" depends on MMC_ATMELMCI && AVR32 && DMA_ENGINE && EXPERIMENTAL diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c index 497dd51..b133baa 100644 --- a/drivers/mmc/host/atmel-mci.c +++ b/drivers/mmc/host/atmel-mci.c @@ -65,6 +65,15 @@ struct atmel_mci_dma { #endif }; +/* + * Configuration options from the kernel config + */ +#ifdef CONFIG_MMC_ATMELMCI_ALWAYS_RESET +#define MMC_ALWAYS_RESET 1 +#else +#define MMC_ALWAYS_RESET 0 +#endif + /** * struct atmel_mci - MMC controller state shared between all slots * @lock: Spinlock protecting the queue and associated data. @@ -714,7 +723,7 @@ static void atmci_start_request(struct atmel_mci *host, host->completed_events = 0; host->data_status = 0; - if (host->need_reset) { + if (host->need_reset || MMC_ALWAYS_RESET) { mci_writel(host, CR, MCI_CR_SWRST); mci_writel(host, CR, MCI_CR_MCIEN); mci_writel(host, MR, host->mode_reg); -- 1.6.0.4