From 3f401908c5761e7c077f6c735abdcac037c281d9 Mon Sep 17 00:00:00 2001
From: Tony Lindgren <tony@atomide.com>
Date: Thu, 11 Aug 2005 07:02:01 -0700
Subject: [PATCH] ARM: OMAP: Fix writes on some MMC cards

Some MMC cards don't set the R1_READY_FOR_DATA bit if EOFB
interrupt comes first. In this case we need to mask R1_READY_FOR_DATA
to avoid polling card status forever.
---
 drivers/mmc/mmc_block.c |  6 ++++++
 drivers/mmc/omap.c      | 25 +++++++++++++++++++++----
 2 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/mmc_block.c b/drivers/mmc/mmc_block.c
index 808f9132011..09efec1790c 100644
--- a/drivers/mmc/mmc_block.c
+++ b/drivers/mmc/mmc_block.c
@@ -270,6 +270,10 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
 			goto cmd_fail;
 		}
 
+		/* No need to check card status after a read */
+		if (rq_data_dir(req) == READ)
+			goto card_ready;
+
 		do {
 			int err;
 
@@ -299,6 +303,8 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
 			goto cmd_err;
 #endif
 
+	card_ready:
+
 		/*
 		 * A block was successfully transferred.
 		 */
diff --git a/drivers/mmc/omap.c b/drivers/mmc/omap.c
index 28b16246512..f0c827e2ca6 100644
--- a/drivers/mmc/omap.c
+++ b/drivers/mmc/omap.c
@@ -326,7 +326,7 @@ mmc_omap_dma_done(struct mmc_omap_host *host, struct mmc_data *data)
 }
 
 static void
-mmc_omap_cmd_done(struct mmc_omap_host *host, struct mmc_command *cmd)
+mmc_omap_cmd_done(struct mmc_omap_host *host, struct mmc_command *cmd, int card_ready)
 {
 	host->cmd = NULL;
 
@@ -340,6 +340,10 @@ mmc_omap_cmd_done(struct mmc_omap_host *host, struct mmc_command *cmd)
 			OMAP_MMC_READ(host->base, RSP6) |
 			(OMAP_MMC_READ(host->base, RSP7) << 16);
 		DBG("MMC%d: Response %08x\n", host->id, cmd->resp[0]);
+		if (card_ready) {
+			pr_debug("MMC%d: Faking card ready based on EOFB\n", host->id);
+			cmd->resp[0] |= R1_READY_FOR_DATA;
+		}
 		break;
 	case MMC_RSP_LONG:
 		/* response type 2 */
@@ -458,6 +462,7 @@ static irqreturn_t mmc_omap_irq(int irq, void *dev_id, struct pt_regs *regs)
 	u16 status;
 	int end_command;
 	int end_transfer;
+	int card_ready;
 	int transfer_error;
 
 	if (host->cmd == NULL && host->data == NULL) {
@@ -472,6 +477,7 @@ static irqreturn_t mmc_omap_irq(int irq, void *dev_id, struct pt_regs *regs)
 
 	end_command = 0;
 	end_transfer = 0;
+	card_ready = 0;
 	transfer_error = 0;
 
 	while ((status = OMAP_MMC_READ(host->base, STAT)) != 0) {
@@ -558,8 +564,8 @@ static irqreturn_t mmc_omap_irq(int irq, void *dev_id, struct pt_regs *regs)
 					| (OMAP_MMC_READ(host->base, RSP7) << 16);
 				/* STOP sometimes sets must-ignore bits */
 				if (!(response & (R1_CC_ERROR
-	| R1_ILLEGAL_COMMAND
-	| R1_COM_CRC_ERROR))) {
+						  | R1_ILLEGAL_COMMAND
+						  | R1_COM_CRC_ERROR))) {
 					end_command = 1;
 					continue;
 				}
@@ -587,10 +593,21 @@ static irqreturn_t mmc_omap_irq(int irq, void *dev_id, struct pt_regs *regs)
 			// End of command phase
 			end_command = 1;
 		}
+
+		/*
+		 * Some cards produce EOFB interrupt and never
+		 * raise R1_READY_FOR_DATA bit after that.
+		 * To avoid infinite card status polling loop,
+		 * we must fake that bit to MMC layer.
+		 */
+		if ((status & OMAP_MMC_STAT_END_OF_CMD) &&
+		    (status & OMAP_MMC_STAT_END_BUSY)) {
+			card_ready = 1;
+		}
 	}
 
 	if (end_command) {
-		mmc_omap_cmd_done(host, host->cmd);
+		mmc_omap_cmd_done(host, host->cmd, card_ready);
 	}
 	if (transfer_error)
 		mmc_omap_xfer_done(host, host->data);
-- 
2.41.1