mmc: xenon_sdhci: remove wait_dat0 SDHCI OP

Generic SDHCI driver received support for checking the busy status by
polling the DAT[0] level instead of waiting for the worst MMC switch time.

Unfortunately, it appears that this does not work for Xenon controllers
despite being a part of the standard SDHCI registers and the Armada 3720
datasheet itself telling that BIT(20) is useful for detecting the DAT[0]
busy signal.

I have tried increasing the timeout value, but I have newer managed to
catch DAT_LEVEL bits change from 0 at all.

This issue appears to hit most if not all SoC-s supported by Xenon driver,
at least A3720, A8040 and CN9130 have non working eMMC currently.

So, until a better solution is found drop the wait_dat0 OP for Xenon.
I was able to only test it on A3720, but it should work for others as well.

Fixes: 40e6f52454fc ("drivers: mmc: Add wait_dat0 support for sdhci driver")
Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: Stefan Roese <sr@denx.de>

diff --git a/drivers/mmc/xenon_sdhci.c b/drivers/mmc/xenon_sdhci.c
index e292f29..2f88050 100644 (file)
--- a/drivers/mmc/xenon_sdhci.c
+++ b/drivers/mmc/xenon_sdhci.c
@@ -439,6 +439,8 @@ static const struct sdhci_ops xenon_sdhci_ops = {
        .set_ios_post = xenon_sdhci_set_ios_post
 };
 
+static struct dm_mmc_ops xenon_mmc_ops;
+
 static int xenon_sdhci_probe(struct udevice *dev)
 {
        struct xenon_sdhci_plat *plat = dev_get_plat(dev);
@@ -452,6 +454,9 @@ static int xenon_sdhci_probe(struct udevice *dev)
        host->mmc->dev = dev;
        upriv->mmc = host->mmc;
 
+       xenon_mmc_ops = sdhci_ops;
+       xenon_mmc_ops.wait_dat0 = NULL;
+
        /* Set quirks */
        host->quirks = SDHCI_QUIRK_WAIT_SEND_CMD | SDHCI_QUIRK_32BIT_DMA_ADDR;
 
@@ -568,7 +573,7 @@ U_BOOT_DRIVER(xenon_sdhci_drv) = {
        .id             = UCLASS_MMC,
        .of_match       = xenon_sdhci_ids,
        .of_to_plat = xenon_sdhci_of_to_plat,
-       .ops            = &sdhci_ops,
+       .ops            = &xenon_mmc_ops,
        .bind           = xenon_sdhci_bind,
        .probe          = xenon_sdhci_probe,
        .remove         = xenon_sdhci_remove,