MLK-14539 mmc: sdhci: make no-1-8-v also work for DDR52 mode

MMC SDHCI maintainer Adrian Hunter Introduce SDHCI flags for signal
voltage support and set them based on the supported transfer modes,
except in the case where 3V DDR52 is supported but 1.8V is not.

This patch add the support to make eMMC DDR52 only work at 3.3v when
property 'no-1-8-v' defined.

Signed-off-by: Haibo Chen <haibo.chen@nxp.com>

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 91e06e4..f3fc617 100644 (file)
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -3341,6 +3341,7 @@ 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_DDR52_3_3V;
        }
 
        /* Any UHS-I mode in caps implies SDR12 and SDR25 support. */
@@ -3480,10 +3481,11 @@ int sdhci_setup_host(struct sdhci_host *host)
                goto unreg;
        }
 
-       if ((mmc->caps & (MMC_CAP_UHS_SDR12 | MMC_CAP_UHS_SDR25 |
+       if (((mmc->caps & (MMC_CAP_UHS_SDR12 | MMC_CAP_UHS_SDR25 |
                          MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR104 |
                          MMC_CAP_UHS_DDR50 | MMC_CAP_1_8V_DDR)) ||
-           (mmc->caps2 & (MMC_CAP2_HS200_1_8V_SDR | MMC_CAP2_HS400_1_8V)))
+           (mmc->caps2 & (MMC_CAP2_HS200_1_8V_SDR | MMC_CAP2_HS400_1_8V))) &&
+           !(mmc->caps2 & MMC_CAP2_DDR52_3_3V))
                host->flags |= SDHCI_SIGNALING_180;
 
        if (mmc->caps2 & MMC_CAP2_HSX00_1_2V)

diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 2eddfa9..71676e5 100644 (file)
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -313,6 +313,7 @@ struct mmc_host {
 #define MMC_CAP2_NO_SD         (1 << 21)       /* Do not send SD commands during initialization */
 #define MMC_CAP2_NO_MMC                (1 << 22)       /* Do not send (e)MMC commands during initialization */
 #define MMC_CAP2_CD_POST       (1 << 23)       /* post card rescan, let client driver to start */
+#define MMC_CAP2_DDR52_3_3V    (1 << 24)       /* Only supprot eMMC DDR52 at 3.3v */
 
        mmc_pm_flag_t           pm_caps;        /* supported pm features */