X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=drivers%2Fi2c%2Fbusses%2Fi2c-s3c2410.c;h=fdd7a4259d2c1216a8f8ca7024e573a2bfb86caf;hb=b7fd4552a67d2e3466931b2808bfc8f22889878e;hp=127eb3805facb55a9f2e6fa0badb4885c709195d;hpb=d8723062a26b17080d89e6b4d360ba50d1e453dd;p=platform%2Fkernel%2Flinux-starfive.git

diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index 127eb38..fdd7a42 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -216,8 +216,17 @@ static bool is_ack(struct s3c24xx_i2c *i2c)
 	int tries;
 
 	for (tries = 50; tries; --tries) {
-		if (readl(i2c->regs + S3C2410_IICCON)
-			& S3C2410_IICCON_IRQPEND) {
+		unsigned long tmp = readl(i2c->regs + S3C2410_IICCON);
+
+		if (!(tmp & S3C2410_IICCON_ACKEN)) {
+			/*
+			 * Wait a bit for the bus to stabilize,
+			 * delay estimated experimentally.
+			 */
+			usleep_range(100, 200);
+			return true;
+		}
+		if (tmp & S3C2410_IICCON_IRQPEND) {
 			if (!(readl(i2c->regs + S3C2410_IICSTAT)
 				& S3C2410_IICSTAT_LASTBIT))
 				return true;