On 08/23/2013 09:44 AM, Mark Brown wrote:

On Mon, Aug 19, 2013 at 12:10:02PM +0800, Huang Shijie wrote:

quoted

+static int fsl_qspi_wait_till_ready(struct fsl_qspi *q)
+{
+	unsigned long deadline;
+	u32 sr;
+
+	deadline = jiffies + msecs_to_jiffies(40000);
+
+	do {
+		if ((sr = fsl_qspi_read_sr(q)) < 0)
+			break;
+		else if (!(sr & SR_WIP))
+			return 0;
+
+		cond_resched();
+
+	} while (!time_after_eq(jiffies, deadline));
+
+	return 1;
+}

Return an error code if we time out?

You also need to check that you didn't complete between your last 
fsl_qspi_read_sr() and the time_arter_eq() check. Theoretically, there 
could be a lot of time between them (due to cond_resched(), for 
instance). 40000 milliseconds is also a lot of time, but still...

IOW, add a check before the "return -ESOMETHING", something like this:

if (!(fsl_qspi_read_sr(q) & SR_WIP))
	return 0;

Brian