[PATCH 1/4] mmc: sdhci: add quirk for ACMD23 broken

From: Scott Branden
Date: Thu Mar 05 2015 - 10:59:19 EST


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@xxxxxxxxxxxx>
Signed-off-by: Scott Branden <sbranden@xxxxxxxxxxxx>

Signed-off-by: Scott Branden <sbranden@xxxxxxxxxxxx>
---
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 f1a488e..fcf78ab 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -3085,7 +3085,8 @@ 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 f767a0d..a29e9bb 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -106,6 +106,8 @@ struct sdhci_host {
#define SDHCI_QUIRK2_CLEAR_TRANSFERMODE_REG_BEFORE_CMD (1<<10)
/* Capability register bit-63 indicates HS400 support */
#define SDHCI_QUIRK2_CAPS_BIT63_FOR_HS400 (1<<11)
+/* Controller broken with using ACMD23 */
+#define SDHCI_QUIRK2_ACMD23_BROKEN (1<<12)

int irq; /* Device IRQ */
void __iomem *ioaddr; /* Mapped address */
--
2.2.2

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