From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753097AbcEIMGU (ORCPT ); Mon, 9 May 2016 08:06:20 -0400 Received: from mga01.intel.com ([192.55.52.88]:8317 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751640AbcEIMGR (ORCPT ); Mon, 9 May 2016 08:06:17 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,600,1455004800"; d="scan'208";a="802192109" Subject: Re: [PATCH v2 5/6] mmc: sdhci: implement enhanced strobe callback To: Shawn Lin , Ulf Hansson References: <1461897751-28810-1-git-send-email-shawn.lin@rock-chips.com> <1461898103-29026-1-git-send-email-shawn.lin@rock-chips.com> Cc: Jaehoon Chung , Michal Simek , soren.brinkmann@xilinx.com, Rob Herring , linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, Doug Anderson , Heiko Stuebner , linux-rockchip@lists.infradead.org, devicetree@vger.kernel.org From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Message-ID: <57307C4B.2040003@intel.com> Date: Mon, 9 May 2016 15:02:19 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <1461898103-29026-1-git-send-email-shawn.lin@rock-chips.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 29/04/16 05:48, Shawn Lin wrote: > Enhanced strobe stuff currently is beyond the scope > of Secure Digital Host Controller Interface. So we can't > find a register here to enable/disable it. We experct > variant drivers to finish the details according to their > vendor settings. > > Signed-off-by: Shawn Lin > --- > > Changes in v2: None > > drivers/mmc/host/sdhci.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > index 94cffa7..a04e4c4 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -2049,6 +2049,16 @@ out_unlock: > return err; > } > > +static int sdhci_prepare_enhanced_strobe(struct mmc_host *mmc, bool enable) > +{ > + /* > + * Currently we can't find a register to enable enhanced strobe > + * function for standard sdhci, so we expect variant drivers to > + * overwrite it. > + */ > + return -EINVAL; > +} Since we don't need it at the moment, let's not have it at all for now. > + > static int sdhci_select_drive_strength(struct mmc_card *card, > unsigned int max_dtr, int host_drv, > int card_drv, int *drv_type) > @@ -2158,6 +2168,7 @@ static const struct mmc_host_ops sdhci_ops = { > .enable_sdio_irq = sdhci_enable_sdio_irq, > .start_signal_voltage_switch = sdhci_start_signal_voltage_switch, > .prepare_hs400_tuning = sdhci_prepare_hs400_tuning, > + .prepare_enhanced_strobe = sdhci_prepare_enhanced_strobe, > .execute_tuning = sdhci_execute_tuning, > .select_drive_strength = sdhci_select_drive_strength, > .card_event = sdhci_card_event, >