From: Adrian Hunter <ext-adrian.hunter@nokia.com>
Date: Thu, 14 Aug 2008 11:00:12 +0000 (+0300)
Subject: [MTD] [OneNAND] OMAP3: add delay for GPIO
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=782b7a367d81da005d93b28cb00f9ae086773c24;p=deliverable%2Flinux.git

[MTD] [OneNAND] OMAP3: add delay for GPIO

On OMAP3, the driver was occasionally not seeing the GPIO
interrupt.  Adding a small delay of one register read
eliminates the problem.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
---

diff --git a/drivers/mtd/onenand/omap2.c b/drivers/mtd/onenand/omap2.c
index 40153ace5df6..34b42533f4bb 100644
--- a/drivers/mtd/onenand/omap2.c
+++ b/drivers/mtd/onenand/omap2.c
@@ -141,8 +141,13 @@ static int omap2_onenand_wait(struct mtd_info *mtd, int state)
 
 		/* Turn interrupts on */
 		syscfg = read_reg(c, ONENAND_REG_SYS_CFG1);
-		syscfg |= ONENAND_SYS_CFG1_IOBE;
-		write_reg(c, syscfg, ONENAND_REG_SYS_CFG1);
+		if (!(syscfg & ONENAND_SYS_CFG1_IOBE)) {
+			syscfg |= ONENAND_SYS_CFG1_IOBE;
+			write_reg(c, syscfg, ONENAND_REG_SYS_CFG1);
+			if (cpu_is_omap34xx())
+				/* Add a delay to let GPIO settle */
+				syscfg = read_reg(c, ONENAND_REG_SYS_CFG1);
+		}
 
 		INIT_COMPLETION(c->irq_done);
 		if (c->gpio_irq) {