OMAP2/3: gpmc-onenand: correct use of async timings

Use async timings when sync timings are not requested.

Also ensure that OneNAND is in async mode when async
timings are used.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/mach-omap2/gpmc-onenand.c b/arch/arm/mach-omap2/gpmc-onenand.c
index 2fd22f9..54fec53 100644
--- a/arch/arm/mach-omap2/gpmc-onenand.c
+++ b/arch/arm/mach-omap2/gpmc-onenand.c
@@ -31,6 +31,8 @@
 static int omap2_onenand_set_async_mode(int cs, void __iomem *onenand_base)
 {
 	struct gpmc_timings t;
+	u32 reg;
+	int err;
 
 	const int t_cer = 15;
 	const int t_avdp = 12;
@@ -43,6 +45,11 @@
 	const int t_wpl = 40;
 	const int t_wph = 30;
 
+	/* Ensure sync read and sync write are disabled */
+	reg = readw(onenand_base + ONENAND_REG_SYS_CFG1);
+	reg &= ~ONENAND_SYS_CFG1_SYNC_READ & ~ONENAND_SYS_CFG1_SYNC_WRITE;
+	writew(reg, onenand_base + ONENAND_REG_SYS_CFG1);
+
 	memset(&t, 0, sizeof(t));
 	t.sync_clk = 0;
 	t.cs_on = 0;
@@ -74,7 +81,16 @@
 			  GPMC_CONFIG1_DEVICESIZE_16 |
 			  GPMC_CONFIG1_MUXADDDATA);
 
-	return gpmc_cs_set_timings(cs, &t);
+	err = gpmc_cs_set_timings(cs, &t);
+	if (err)
+		return err;
+
+	/* Ensure sync read and sync write are disabled */
+	reg = readw(onenand_base + ONENAND_REG_SYS_CFG1);
+	reg &= ~ONENAND_SYS_CFG1_SYNC_READ & ~ONENAND_SYS_CFG1_SYNC_WRITE;
+	writew(reg, onenand_base + ONENAND_REG_SYS_CFG1);
+
+	return 0;
 }
 
 static void set_onenand_cfg(void __iomem *onenand_base, int latency,
@@ -124,7 +140,8 @@
 	} else if (cfg->flags & ONENAND_SYNC_READWRITE) {
 		sync_read = 1;
 		sync_write = 1;
-	}
+	} else
+		return omap2_onenand_set_async_mode(cs, onenand_base);
 
 	if (!freq) {
 		/* Very first call freq is not known */