mmc: sdhci: add DDR50 1.8V mode support for BayTrail eMMC Controller

This is to enable DDR50 bus speed mode with 1.8V signaling capability
for BayTrail ACPI and PCI mode eMMC Controller.
Signed-off-by: Maurice Petallo <mauricex.r.petallo@intel.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci-acpi.c

@@ -124,7 +124,8 @@ static const struct sdhci_acpi_chip sdhci_acpi_chip_int = {
 
 static const struct sdhci_acpi_slot sdhci_acpi_slot_int_emmc = {
 	.chip    = &sdhci_acpi_chip_int,
-	.caps    = MMC_CAP_8_BIT_DATA | MMC_CAP_NONREMOVABLE | MMC_CAP_HW_RESET,
+	.caps    = MMC_CAP_8_BIT_DATA | MMC_CAP_NONREMOVABLE |
+		   MMC_CAP_HW_RESET | MMC_CAP_1_8V_DDR,
 	.caps2   = MMC_CAP2_HC_ERASE_SZ,
 	.flags   = SDHCI_ACPI_RUNTIME_PM,
 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,

drivers/mmc/host/sdhci-pci.c

@@ -268,7 +268,7 @@ static void sdhci_pci_int_hw_reset(struct sdhci_host *host)
 static int byt_emmc_probe_slot(struct sdhci_pci_slot *slot)
 {
 	slot->host->mmc->caps |= MMC_CAP_8_BIT_DATA | MMC_CAP_NONREMOVABLE |
-				 MMC_CAP_HW_RESET;
+				 MMC_CAP_HW_RESET | MMC_CAP_1_8V_DDR;
 	slot->host->mmc->caps2 |= MMC_CAP2_HC_ERASE_SZ;
 	slot->hw_reset = sdhci_pci_int_hw_reset;
 	return 0;