From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: Re: [PATCH v4 05/12] mmc: sdhci: Disable HS200/HS400 mode if controller can't support 1.8v Date: Thu, 26 Apr 2018 11:55:20 +0300 Message-ID: <6bdf4feb-bc12-3779-3de6-e08af1d4f518@intel.com> References: <20180425120937.29867-1-kishon@ti.com> <20180425120937.29867-6-kishon@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180425120937.29867-6-kishon@ti.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Kishon Vijay Abraham I , Ulf Hansson Cc: Rob Herring , Mark Rutland , linux-mmc@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, Tony Lindgren List-Id: linux-omap@vger.kernel.org On 25/04/18 15:09, Kishon Vijay Abraham I wrote: > Though MMC controller can indicate HS200/HS400 mode capability (by > using "mmc-hs200-1_8v"/"mmc-hs400-1_8v" dt property), if the IO lines > in the board is connected to 3.3v supply, HS200/HS400 mode cannot be > supported. Such boards have "no-1-8-v" property in their dts file. > Disable HS200/HS400 mode for boards which have "no-1-8-v" set. > > Signed-off-by: Kishon Vijay Abraham I > Acked-by: Tony Lindgren > --- > drivers/mmc/host/sdhci.c | 1 + > include/linux/mmc/host.h | 1 + > 2 files changed, 2 insertions(+) > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > index 2ededa7f43df..b5f047b5f3ae 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -3672,6 +3672,7 @@ int sdhci_setup_host(struct sdhci_host *host) > if (host->quirks2 & SDHCI_QUIRK2_NO_1_8_V) { > host->caps1 &= ~(SDHCI_SUPPORT_SDR104 | SDHCI_SUPPORT_SDR50 | > SDHCI_SUPPORT_DDR50); > + mmc->caps2 &= ~MMC_CAP2_HSX00_1_8V; Seems weird for sdhci to clear flags it never set. Also couldn't we reasonably expect dt properties to be consistent? Is this really about setting SDHCI_QUIRK2_NO_1_8_V in your driver and expecting it to override other dt properties? Although that still begs the question why anyone would set dt properties that the hardware doesn't support? I guess you should also clear MMC_CAP2_HS400_ES. > } > > /* Any UHS-I mode in caps implies SDR12 and SDR25 support. */ > diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h > index 7c6eaf63f5ce..58832451767b 100644 > --- a/include/linux/mmc/host.h > +++ b/include/linux/mmc/host.h > @@ -345,6 +345,7 @@ struct mmc_host { > #define MMC_CAP2_HS400_1_2V (1 << 16) /* Can support HS400 1.2V */ > #define MMC_CAP2_HS400 (MMC_CAP2_HS400_1_8V | \ > MMC_CAP2_HS400_1_2V) > +#define MMC_CAP2_HSX00_1_8V (MMC_CAP2_HS200_1_8V_SDR | MMC_CAP2_HS400_1_8V) > #define MMC_CAP2_HSX00_1_2V (MMC_CAP2_HS200_1_2V_SDR | MMC_CAP2_HS400_1_2V) > #define MMC_CAP2_SDIO_IRQ_NOTHREAD (1 << 17) > #define MMC_CAP2_NO_WRITE_PROTECT (1 << 18) /* No physical write protect pin, assume that card is always read-write */ >