From patchwork Fri Dec 2 13:14:22 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adrian Hunter X-Patchwork-Id: 9458371 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id DA49160761 for ; Fri, 2 Dec 2016 13:20:22 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CD17928558 for ; Fri, 2 Dec 2016 13:20:22 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C1CD228556; Fri, 2 Dec 2016 13:20:22 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DF6E828558 for ; Fri, 2 Dec 2016 13:20:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932173AbcLBNUG (ORCPT ); Fri, 2 Dec 2016 08:20:06 -0500 Received: from mga03.intel.com ([134.134.136.65]:19569 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759294AbcLBNTp (ORCPT ); Fri, 2 Dec 2016 08:19:45 -0500 Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga103.jf.intel.com with ESMTP; 02 Dec 2016 05:19:35 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,729,1477983600"; d="scan'208";a="1067086216" Received: from ahunter-desktop.fi.intel.com ([10.237.72.168]) by orsmga001.jf.intel.com with ESMTP; 02 Dec 2016 05:19:33 -0800 From: Adrian Hunter To: Ulf Hansson Cc: linux-mmc Subject: [PATCH V2 4/9] mmc: sdhci: Always allow tuning to fall back to fixed sampling Date: Fri, 2 Dec 2016 15:14:22 +0200 Message-Id: <1480684467-26833-5-git-send-email-adrian.hunter@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1480684467-26833-1-git-send-email-adrian.hunter@intel.com> References: <1480684467-26833-1-git-send-email-adrian.hunter@intel.com> Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP SDHCI falls back to fixed sampling if there is an error during tuning. However it also reports an error unless there is periodic re-tuning. That is not the best option because: a) there is a reasonable chance that fixed sampling will work, especially at room temperature. b) re-tuning will be done again anyway if there are CRC errors. Change to return no error always when falling back to fixed sampling. Signed-off-by: Adrian Hunter --- drivers/mmc/host/sdhci.c | 20 ++------------------ 1 file changed, 2 insertions(+), 18 deletions(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index ad2f2c6113e4..a23887799f43 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2098,8 +2098,6 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode) sdhci_do_reset(host, SDHCI_RESET_CMD); sdhci_do_reset(host, SDHCI_RESET_DATA); - err = -EIO; - if (cmd.opcode != MMC_SEND_TUNING_BLOCK_HS200) goto out; @@ -2137,24 +2135,10 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode) ctrl &= ~SDHCI_CTRL_EXEC_TUNING; sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2); } - if (!(ctrl & SDHCI_CTRL_TUNED_CLK)) { + if (!(ctrl & SDHCI_CTRL_TUNED_CLK)) pr_info(DRIVER_NAME ": Tuning procedure failed, falling back to fixed sampling clock\n"); - err = -EIO; - } - out: - if (tuning_count) { - /* - * In case tuning fails, host controllers which support - * re-tuning can try tuning again at a later time, when the - * re-tuning timer expires. So for these controllers, we - * return 0. Since there might be other controllers who do not - * have this capability, we return error for them. - */ - err = 0; - } - - host->mmc->retune_period = err ? 0 : tuning_count; + host->mmc->retune_period = tuning_count; sdhci_writel(host, host->ier, SDHCI_INT_ENABLE); sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);