From mboxrd@z Thu Jan 1 00:00:00 1970 From: Balaji T K Subject: Re: [PATCH 3/7] mmc: omap: clarify DDR timing mode between SD-UHS and eMMC Date: Thu, 16 Jan 2014 16:37:55 +0530 Message-ID: <52D7BD8B.4060300@ti.com> References: <1383653403-10049-1-git-send-email-ulf.hansson@linaro.org> <002101cf11fb$bf5c6280$3e152780$%jun@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from bear.ext.ti.com ([192.94.94.41]:60192 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751669AbaAPLIN (ORCPT ); Thu, 16 Jan 2014 06:08:13 -0500 In-Reply-To: Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Ulf Hansson Cc: Seungwon Jeon , Chris Ball , linux-mmc On Thursday 16 January 2014 04:19 PM, Ulf Hansson wrote: > On 15 January 2014 15:11, Seungwon Jeon wrote: >> Replaced UHS_DDR50 with MMC_DDR52. >> >> CC: Balaji T K >> Signed-off-by: Seungwon Jeon >> --- >> drivers/mmc/host/omap_hsmmc.c | 4 ++-- >> 1 files changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c >> index dbd32ad..cca397e 100644 >> --- a/drivers/mmc/host/omap_hsmmc.c >> +++ b/drivers/mmc/host/omap_hsmmc.c >> @@ -540,7 +540,7 @@ static void omap_hsmmc_set_clock(struct omap_hsmmc_host *host) >> * - MMC/SD clock coming out of controller > 25MHz >> */ >> if ((mmc_slot(host).features & HSMMC_HAS_HSPE_SUPPORT) && >> - (ios->timing != MMC_TIMING_UHS_DDR50) && >> + (ios->timing != MMC_TIMING_MMC_DDR52) && > > Even if I can't find anywhere that OMAP has enabled the corresponding > host caps for UHS SD cards, it still might be the case that OMAP > actually is able to handle the 1.8V I/O voltage switches and thus you > should like keep that. > Hi, Actually the ios->timing check currently there is for eMMC DDR, So this change is needed. > You find the omap specific hack in omap_hsmmc_switch_opcond(). Ideally switch_opcond is for 1.8V MMC (MMC mobile) cards. > the driver should be updated to implement the > host_ops->start_signal_voltage_switch and host_ops->card_busy instead. > uhs support for sd card is not yet in mainline. voltage_switch and card_busy ops will be get implemented for UHS sd card support. Thanks and Regards, Balaji T K > Maybe some the OMAP guys can tell use more to be sure. > > Kind regards > Ulf Hansson > > >> ((OMAP_HSMMC_READ(host->base, CAPA) & HSS) == HSS)) { >> regval = OMAP_HSMMC_READ(host->base, HCTL); >> if (clkdiv && (clk_get_rate(host->fclk)/clkdiv) > 25000000) >> @@ -560,7 +560,7 @@ static void omap_hsmmc_set_bus_width(struct omap_hsmmc_host *host) >> u32 con; >> >> con = OMAP_HSMMC_READ(host->base, CON); >> - if (ios->timing == MMC_TIMING_UHS_DDR50) >> + if (ios->timing == MMC_TIMING_MMC_DDR52) >> con |= DDR; /* configure in DDR mode */ >> else >> con &= ~DDR; >> -- >> 1.7.0.4 >> >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html