From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter 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> References: <1480684467-26833-1-git-send-email-adrian.hunter@intel.com> Return-path: 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 In-Reply-To: <1480684467-26833-1-git-send-email-adrian.hunter@intel.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Ulf Hansson Cc: linux-mmc 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); -- 1.9.1