[PATCH v2] mmc: sdhci: add quirk for ACMD23 broken

[Scott Branden <sbranden@broadcom.com>]

Add quirk to handle broken auto-CMD23.
Some controllers do not respond after the first auto-CMD23 is issued.

This allows CMD23 to still work (mandatory for the faster UHS-I mode)
rather than disabling CMD23 entirely via SDHCI_QUIRK2_HOST_NO_CMD23.

Signed-off by: Corneliu Doban <cdoban@broadcom.com>
Signed-off-by: Scott Branden <sbranden@broadcom.com>
---
 drivers/mmc/host/sdhci.c  | 3 ++-
 include/linux/mmc/sdhci.h | 2 ++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index ada1a3e..b37331f 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2985,7 +2985,8 @@ int sdhci_add_host(struct sdhci_host *host)
 	/* Auto-CMD23 stuff only works in ADMA or PIO. */
 	if ((host->version >= SDHCI_SPEC_300) &&
 	    ((host->flags & SDHCI_USE_ADMA) ||
-	     !(host->flags & SDHCI_USE_SDMA))) {
+	     !(host->flags & SDHCI_USE_SDMA)) &&
+	     !(host->quirks2 & SDHCI_QUIRK2_ACMD23_BROKEN)) {
 		host->flags |= SDHCI_AUTO_CMD23;
 		DBG("%s: Auto-CMD23 available\n", mmc_hostname(mmc));
 	} else {
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index dba793e..d979cf9 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -100,6 +100,8 @@ struct sdhci_host {
 #define SDHCI_QUIRK2_BROKEN_DDR50			(1<<7)
 /* Stop command (CMD12) can set Transfer Complete when not using MMC_RSP_BUSY */
 #define SDHCI_QUIRK2_STOP_WITH_TC			(1<<8)
+/* Controller broken with using ACMD23 */
+#define SDHCI_QUIRK2_ACMD23_BROKEN			(1<<9)
 
 	int irq;		/* Device IRQ */
 	void __iomem *ioaddr;	/* Mapped address */
-- 
2.2.0