mtd: fix the wrong timeo for panic_nand_wait()

The panic_nand_wait() expects the timeo in ms and not in jiffies.
But in nand_wait(), the timeo for panic_nand_wait() is assigned with
wrong value(jiffies + some delay). The timeo should be set like the
panic_nand_write() does.

This patch passes timeo in ms to panic_nand_wait().
And this patch also passes timeo in jiffies(converted by msecs_to_jiffies)
to time_before() which makes the code more readable.
Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

drivers/mtd/nand/nand_base.c

@@ -825,13 +825,8 @@ static void panic_nand_wait(struct mtd_info *mtd, struct nand_chip *chip,
 static int nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
 {
 
-	unsigned long timeo = jiffies;
 	int status, state = chip->state;
-
-	if (state == FL_ERASING)
-		timeo += (HZ * 400) / 1000;
-	else
-		timeo += (HZ * 20) / 1000;
+	unsigned long timeo = (state == FL_ERASING ? 400 : 20);
 
 	led_trigger_event(nand_led_trigger, LED_FULL);
 
@@ -849,6 +844,7 @@ static int nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
 	if (in_interrupt() || oops_in_progress)
 		panic_nand_wait(mtd, chip, timeo);
 	else {
+		timeo = jiffies + msecs_to_jiffies(timeo);
 		while (time_before(jiffies, timeo)) {
 			if (chip->dev_ready) {
 				if (chip->dev_ready(mtd))