[patch 4/7] SDHCI: Add quirk for controller with no end-of-busy IRQ

[Ben Dooks <ben-linux@fluff.org>]

[-- Attachment #1: simtec/s3c64xx/sdhci-add-no-busy-transfer-finish-irq-quirk.patch --]
[-- Type: text/plain, Size: 2378 bytes --]

The Samsung SDHCI controller block seems to fail to generate an
INT_DATA_END after the transfer has completed and the bus busy
state finished. 

Changes in e809517f6fa5803a5a1cd56026f0e2190fc13d5c to use the
new busy method are the cause of the behaviour change.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>

Index: linux.git/drivers/mmc/host/sdhci.c
===================================================================
--- linux.git.orig/drivers/mmc/host/sdhci.c	2008-11-03 10:01:03.000000000 +0000
+++ linux.git/drivers/mmc/host/sdhci.c	2008-11-03 12:20:40.000000000 +0000
@@ -1291,11 +1291,24 @@ static void sdhci_cmd_irq(struct sdhci_h
 	 *       controllers.
 	 */
 	if (host->cmd->flags & MMC_RSP_BUSY) {
+		u32 present;
+
 		if (host->cmd->data)
 			DBG("Cannot wait for busy signal when also "
 				"doing a data transfer");
-		else
+		else if (!(host->quirks & SDHCI_QUIRK_NO_TCIRQ_ON_NOT_BUSY))
 			return;
+
+		/* The Samsung SDHCI does not seem to provide an INT_DATA_END
+		 * when the system goes non-busy, so check the state of the
+		 * transfer by reading SDHCI_PRESENT_STATE to see if the
+		 * controller is ready
+		 */
+
+		present = readl(host->ioaddr + SDHCI_PRESENT_STATE);
+		DBG("busy? present %08x, intstat %08x\n", present, intmask);
+
+		/* fall through and take the SDHCI_INT_RESPONSE */
 	}
 
 	if (intmask & SDHCI_INT_RESPONSE)
Index: linux.git/drivers/mmc/host/sdhci.h
===================================================================
--- linux.git.orig/drivers/mmc/host/sdhci.h	2008-11-03 10:01:03.000000000 +0000
+++ linux.git/drivers/mmc/host/sdhci.h	2008-11-03 12:20:00.000000000 +0000
@@ -57,6 +57,7 @@
 #define  SDHCI_DATA_AVAILABLE	0x00000800
 #define  SDHCI_CARD_PRESENT	0x00010000
 #define  SDHCI_WRITE_PROTECT	0x00080000
+#define  SDHCI_DATA_BIT(x)	(1 << ((x) + 20))
 
 #define SDHCI_HOST_CONTROL 	0x28
 #define  SDHCI_CTRL_LED		0x01
@@ -210,6 +211,8 @@ struct sdhci_host {
 #define SDHCI_QUIRK_BROKEN_SMALL_PIO			(1<<13)
 /* Controller supports high speed but doesn't have the caps bit set */
 #define SDHCI_QUIRK_FORCE_HIGHSPEED			(1<<14)
+/* Controller does not provide transfer-complete interrupt when not busy */
+#define SDHCI_QUIRK_NO_TCIRQ_ON_NOT_BUSY		(1<<15)
 
 	int			irq;		/* Device IRQ */
 	void __iomem *		ioaddr;		/* Mapped address */

-- 
Ben (ben@fluff.org, http://www.fluff.org/)

  'a smiley only costs 4 bytes'