[PATCH V1 1/2] mmc: sdhci: Introduce new quirk to use reserved timeout

[Sarthak Garg <sartgarg@codeaurora.org>]

Introduce a new quirk for letting vendor drivers to use reserved
timeout value (0xF) in timeout control register.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Sarthak Garg <sartgarg@codeaurora.org>
---
 drivers/mmc/host/sdhci.c | 3 ++-
 drivers/mmc/host/sdhci.h | 5 +++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 1bb6b67..07528a9 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -967,7 +967,8 @@ static u8 sdhci_calc_timeout(struct sdhci_host *host, struct mmc_command *cmd,
 	}
 
 	if (count >= 0xF) {
-		if (!(host->quirks2 & SDHCI_QUIRK2_DISABLE_HW_TIMEOUT))
+		if (!(host->quirks2 & SDHCI_QUIRK2_DISABLE_HW_TIMEOUT) ||
+		!(host->quirks2 & SDHCI_QUIRK2_USE_RESERVED_MAX_TIMEOUT))
 			DBG("Too large timeout 0x%x requested for CMD%d!\n",
 			    count, cmd->opcode);
 		count = 0xE;
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 8d2a096..02f8779 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -476,6 +476,11 @@ struct sdhci_host {
  * block count.
  */
 #define SDHCI_QUIRK2_USE_32BIT_BLK_CNT			(1<<18)
+/*
+ * Some controllers define the usage of 0xF in data timeout counter
+ * register (0x2E) which is actually a reserved bit as per specification.
+ */
+#define SDHCI_QUIRK2_USE_RESERVED_MAX_TIMEOUT		(1<<19)
 
 	int irq;		/* Device IRQ */
 	void __iomem *ioaddr;	/* Mapped address */
-- 
2.7.4