[patchv3 5/5] MMC: SDHCI AutoCMD23 support.

[Andrei Warkentin <andreiw@motorola.com>]

Enables Auto-CMD23 support where available (SDHCI 3.0 controllers)

Cc: arindam.nath@amd.com
Cc: cjb@laptop.org
Cc: arnd@arndb.de
Cc: subhashj@codeaurora.org
Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
---
 drivers/mmc/host/Kconfig  |    9 +++++++++
 drivers/mmc/host/sdhci.c  |   16 +++++++++++++++-
 drivers/mmc/host/sdhci.h  |    2 ++
 include/linux/mmc/sdhci.h |    1 +
 4 files changed, 27 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index b981715..d4e5658 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -68,6 +68,15 @@ config MMC_SDHCI_PCI
 
 	  If unsure, say N.
 
+config MMC_SDHCI_AUTO_CMD23
+       tristate "SDHCI 3.0 Auto-CMD23 support (EXPERIMENTAL)"
+       depends on MMC_SDHCI && EXPERIMENTAL
+       help
+         This enables the Auto-CMD23 optimization for multiblock
+         transfers where a CMD23 would be sent
+
+         If unsure, say N.
+
 config MMC_RICOH_MMC
 	bool "Ricoh MMC Controller Disabler  (EXPERIMENTAL)"
 	depends on MMC_SDHCI_PCI
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 41c987d..e7a38b6 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -844,7 +844,13 @@ static void sdhci_set_transfer_mode(struct sdhci_host *host,
 		if (!host->mrq->sbc &&
 		    host->flags & SDHCI_ACMD12)
 			mode |= SDHCI_TRNS_ACMD12;
+		else if (host->mrq->sbc &&
+			 host->flags & SDHCI_ACMD23) {
+			mode |= SDHCI_TRNS_ACMD23;
+			sdhci_writel(host, data->blocks, SDHCI_ARGUMENT2);
+		}
 	}
+
 	if (data->flags & MMC_DATA_READ)
 		mode |= SDHCI_TRNS_READ;
 	if (host->flags & SDHCI_REQ_USE_DMA)
@@ -1189,7 +1195,7 @@ static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq)
 		tasklet_schedule(&host->finish_tasklet);
 	} else {
 
-		if (mrq->sbc)
+		if (mrq->sbc && !(host->flags & SDHCI_ACMD23))
 			sdhci_send_command(host, mrq->sbc);
 		else
 			sdhci_send_command(host, mrq->cmd);
@@ -1947,6 +1953,14 @@ int sdhci_add_host(struct sdhci_host *host)
 	if (host->quirks & SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12)
 		host->flags |= SDHCI_ACMD12;
 
+#ifdef CONFIG_MMC_SDHCI_CMD23
+	/* Auto-CMD23 stuff only works in ADMA or PIO. */
+	if ((host->version == SDHCI_SPEC_300) &&
+	    ((host->flags & SDHCI_USE_ADMA) ||
+	     !(host->flags & SDHCI_REQ_USE_DMA)))
+		host->flags |= SDHCI_ACMD23;
+#endif
+
 	/*
 	 * A controller may support 8-bit width, but the board itself
 	 * might not have the pins brought out.  Boards that support
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 85750a9..2b3fb76 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -25,6 +25,7 @@
  */
 
 #define SDHCI_DMA_ADDRESS	0x00
+#define SDHCI_ARGUMENT2		0x00
 
 #define SDHCI_BLOCK_SIZE	0x04
 #define  SDHCI_MAKE_BLKSZ(dma, blksz) (((dma & 0x7) << 12) | (blksz & 0xFFF))
@@ -37,6 +38,7 @@
 #define  SDHCI_TRNS_DMA		0x01
 #define  SDHCI_TRNS_BLK_CNT_EN	0x02
 #define  SDHCI_TRNS_ACMD12	0x04
+#define  SDHCI_TRNS_ACMD23	0x08
 #define  SDHCI_TRNS_READ	0x10
 #define  SDHCI_TRNS_MULTI	0x20
 
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index c54ac14..d91585a 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -110,6 +110,7 @@ struct sdhci_host {
 #define SDHCI_REQ_USE_DMA	(1<<2)	/* Use DMA for this req. */
 #define SDHCI_DEVICE_DEAD	(1<<3)	/* Device unresponsive */
 #define SDHCI_ACMD12		(1<<4)	/* Auto CMD12 support */
+#define SDHCI_ACMD23		(1<<5)	/* Auto CMD23 support */
 
 	unsigned int version;	/* SDHCI spec. version */
 
-- 
1.7.0.4