[PATCH] fix misalignment in pxamci

[Marek Vasut <marek.vasut@gmail.com>]

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Hi,
Philipp Zabel finally made the pxamci issue clear. It turned out, that pxamci 
needs the DMA destination address to be aligned to 8 bytes. In some cases it 
happened, that the address was aligned to 4 bytes causing controller to 
incorrectly transfer data (and resulting into error like "mmc0: unrecognised 
SCR structure version 1"). The following patch allows to debug this issue and 
moreover fixes it by moving one 4 byte entry of mmc_card structure, aligning 
the DMA destination back to 8 bytes.

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>

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Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
index 65210fc..75b2810 100644
--- a/drivers/mmc/host/pxamci.c
+++ b/drivers/mmc/host/pxamci.c
@@ -153,6 +153,13 @@ static void pxamci_setup_data(struct pxamci_host *host, struct mmc_data *data)
 		if (length & 31 && !(data->flags & MMC_DATA_READ))
 			host->sg_cpu[i].dcmd |= DCMD_ENDIRQEN;
 		if (data->flags & MMC_DATA_READ) {
+#ifdef CONFIG_MMC_DEBUG
+			/* we need destination address to be aligned to 8 bytes
+			   here, if it isn't, we have serious problem */
+			if (sg_dma_address(&data->sg[i]) % 8)
+				pr_debug("%s:%i Misaligned DMA destination\n",
+					__FILE__, __LINE__);
+#endif
 			host->sg_cpu[i].dsadr = host->res->start + MMC_RXFIFO;
 			host->sg_cpu[i].dtadr = sg_dma_address(&data->sg[i]);
 		} else {
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 0d508ac..cb76462 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -89,6 +89,7 @@ struct mmc_card {
 #define MMC_TYPE_MMC		0		/* MMC card */
 #define MMC_TYPE_SD		1		/* SD card */
 #define MMC_TYPE_SDIO		2		/* SDIO card */
+	unsigned int		sdio_funcs;	/* number of SDIO functions */
 	unsigned int		state;		/* (our) card state */
 #define MMC_STATE_PRESENT	(1<<0)		/* present in sysfs */
 #define MMC_STATE_READONLY	(1<<1)		/* card is read-only */
@@ -104,7 +105,6 @@ struct mmc_card {
 	struct sd_scr		scr;		/* extra SD information */
 	struct sd_switch_caps	sw_caps;	/* switch (CMD6) caps */
 
-	unsigned int		sdio_funcs;	/* number of SDIO functions */
 	struct sdio_cccr	cccr;		/* common card info */
 	struct sdio_cis		cis;		/* common tuple info */
 	struct sdio_func	*sdio_func[SDIO_MAX_FUNCS]; /* SDIO functions (devices) */