The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From d0918764c17b94c30bbb2619929b1719ff52707a Mon Sep 17 00:00:00 2001 From: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx> Date: Tue, 28 Mar 2017 11:00:45 +0200 Subject: [PATCH] mmc: sdhci-of-at91: fix MMC_DDR_52 timing selection The controller has different timings for MMC_TIMING_UHS_DDR50 and MMC_TIMING_MMC_DDR52. Configuring the controller with SDHCI_CTRL_UHS_DDR50, when MMC_TIMING_MMC_DDR52 timings are requested, is not correct and can lead to unexpected behavior. Signed-off-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx> Fixes: bb5f8ea4d514 ("mmc: sdhci-of-at91: introduce driver for the Atmel SDMMC") Cc: <stable@xxxxxxxxxxxxxxx> # 4.4+ Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c index 7fd964256faa..d5430ed02a67 100644 --- a/drivers/mmc/host/sdhci-of-at91.c +++ b/drivers/mmc/host/sdhci-of-at91.c @@ -29,6 +29,8 @@ #include "sdhci-pltfm.h" +#define SDMMC_MC1R 0x204 +#define SDMMC_MC1R_DDR BIT(3) #define SDMMC_CACR 0x230 #define SDMMC_CACR_CAPWREN BIT(0) #define SDMMC_CACR_KEY (0x46 << 8) @@ -103,11 +105,18 @@ static void sdhci_at91_set_power(struct sdhci_host *host, unsigned char mode, sdhci_set_power_noreg(host, mode, vdd); } +void sdhci_at91_set_uhs_signaling(struct sdhci_host *host, unsigned int timing) +{ + if (timing == MMC_TIMING_MMC_DDR52) + sdhci_writeb(host, SDMMC_MC1R_DDR, SDMMC_MC1R); + sdhci_set_uhs_signaling(host, timing); +} + static const struct sdhci_ops sdhci_at91_sama5d2_ops = { .set_clock = sdhci_at91_set_clock, .set_bus_width = sdhci_set_bus_width, .reset = sdhci_reset, - .set_uhs_signaling = sdhci_set_uhs_signaling, + .set_uhs_signaling = sdhci_at91_set_uhs_signaling, .set_power = sdhci_at91_set_power, };