From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 08A48C28B2B for ; Fri, 19 Aug 2022 16:27:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352795AbiHSQ1e (ORCPT ); Fri, 19 Aug 2022 12:27:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36476 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352615AbiHSQYH (ORCPT ); Fri, 19 Aug 2022 12:24:07 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 88801118939; Fri, 19 Aug 2022 09:03:07 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7F7B9617A7; Fri, 19 Aug 2022 16:03:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7D097C433C1; Fri, 19 Aug 2022 16:03:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1660924983; bh=Gz2Jr+pS+jA08IitzJi1AbwCWv5VZEhjC2YGN6UtlOw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iEuRTZFwMorBPElul2lABd0CVrs39ShEuxILLVDDVst59Liv9UvxwX1RjtVpcQRAs AseB3WkEKSYmfr3oZaiU3qFZ3BQSSZp2TE99/EpEj8/IBqIvBjWv81/pziGnf1v94d GZgOs4fVzKrYoAJ2QvQupH3Y1BBRPj+CEGlNSlq4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eugen Hristev , Karl Olsen , Adrian Hunter , Ulf Hansson , Sasha Levin Subject: [PATCH 5.10 316/545] mmc: sdhci-of-at91: fix set_uhs_signaling rewriting of MC1R Date: Fri, 19 Aug 2022 17:41:26 +0200 Message-Id: <20220819153843.500723665@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220819153829.135562864@linuxfoundation.org> References: <20220819153829.135562864@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eugen Hristev [ Upstream commit 5987e6ded29d52e42fc7b06aa575c60a25eee38e ] In set_uhs_signaling, the DDR bit is being set by fully writing the MC1R register. This can lead to accidental erase of certain bits in this register. Avoid this by doing a read-modify-write operation. Fixes: d0918764c17b ("mmc: sdhci-of-at91: fix MMC_DDR_52 timing selection") Signed-off-by: Eugen Hristev Tested-by: Karl Olsen Acked-by: Adrian Hunter Link: https://lore.kernel.org/r/20220630090926.15061-1-eugen.hristev@microchip.com Signed-off-by: Ulf Hansson Signed-off-by: Sasha Levin --- drivers/mmc/host/sdhci-of-at91.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c index d1a1c548c515..0452c312b65e 100644 --- a/drivers/mmc/host/sdhci-of-at91.c +++ b/drivers/mmc/host/sdhci-of-at91.c @@ -100,8 +100,13 @@ static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock) static void sdhci_at91_set_uhs_signaling(struct sdhci_host *host, unsigned int timing) { - if (timing == MMC_TIMING_MMC_DDR52) - sdhci_writeb(host, SDMMC_MC1R_DDR, SDMMC_MC1R); + u8 mc1r; + + if (timing == MMC_TIMING_MMC_DDR52) { + mc1r = sdhci_readb(host, SDMMC_MC1R); + mc1r |= SDMMC_MC1R_DDR; + sdhci_writeb(host, mc1r, SDMMC_MC1R); + } sdhci_set_uhs_signaling(host, timing); } -- 2.35.1