mtd: sh_flctl: Add FLHOLDCR register

Add a register used in new FLCTL hardware and a feature flag for it.
Signed-off-by: Bastian Hecht <hechtb@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/nand/sh_flctl.c

@@ -693,6 +693,8 @@ static void flctl_select_chip(struct mtd_info *mtd, int chipnr)
 	case 0:
 		flctl->flcmncr_base |= CE0_ENABLE;
 		writel(flctl->flcmncr_base, FLCMNCR(flctl));
+		if (flctl->holden)
+			writel(HOLDEN, FLHOLDCR(flctl));
 		break;
 	default:
 		BUG();
@@ -849,6 +851,7 @@ static int __devinit flctl_probe(struct platform_device *pdev)
 	flctl->pdev = pdev;
 	flctl->flcmncr_base = pdata->flcmncr_val;
 	flctl->hwecc = pdata->has_hwecc;
+	flctl->holden = pdata->use_holden;
 
 	nand->options = NAND_NO_AUTOINCR;
 

include/linux/mtd/sh_flctl.h

@@ -38,6 +38,7 @@
 #define FLDTFIFO(f)		(f->reg + 0x24)
 #define FLECFIFO(f)		(f->reg + 0x28)
 #define FLTRCR(f)		(f->reg + 0x2C)
+#define FLHOLDCR(f)		(f->reg + 0x38)
 #define	FL4ECCRESULT0(f)	(f->reg + 0x80)
 #define	FL4ECCRESULT1(f)	(f->reg + 0x84)
 #define	FL4ECCRESULT2(f)	(f->reg + 0x88)
@@ -109,6 +110,15 @@
 #define TRSTRT		(0x1 << 0)	/* translation start */
 #define TREND		(0x1 << 1)	/* translation end */
 
+/*
+ * FLHOLDCR control bits
+ *
+ * HOLDEN: Bus Occupancy Enable (inverted)
+ * Enable this bit when the external bus might be used in between transfers.
+ * If not set and the bus gets used by other modules, a deadlock occurs.
+ */
+#define HOLDEN		(0x1 << 0)
+
 /* FL4ECCCR control bits */
 #define	_4ECCFA		(0x1 << 2)	/* 4 symbols correct fault */
 #define	_4ECCEND	(0x1 << 1)	/* 4 symbols end */
@@ -138,6 +148,7 @@ struct sh_flctl {
 
 	unsigned page_size:1;	/* NAND page size (0 = 512, 1 = 2048) */
 	unsigned hwecc:1;	/* Hardware ECC (0 = disabled, 1 = enabled) */
+	unsigned holden:1;	/* Hardware has FLHOLDCR and HOLDEN is set */
 };
 
 struct sh_flctl_platform_data {
@@ -146,6 +157,7 @@ struct sh_flctl_platform_data {
 	unsigned long		flcmncr_val;
 
 	unsigned has_hwecc:1;
+	unsigned use_holden:1;
 };
 
 static inline struct sh_flctl *mtd_to_flctl(struct mtd_info *mtdinfo)