diff mbox

[3/6] MTD: lantiq: xway: remove endless loop

Message ID 1451941501-42952-4-git-send-email-blogic@openwrt.org
State Changes Requested
Headers show

Commit Message

John Crispin Jan. 4, 2016, 9:04 p.m. UTC 
The reset loop logic could run into a endless loop. Lets fix it as
requested.

http://lists.infradead.org/pipermail/linux-mtd/2012-September/044240.html

Signed-off-by: John Crispin <blogic@openwrt.org>
---
 drivers/mtd/nand/xway_nand.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

Comments

Brian Norris Jan. 4, 2016, 11:39 p.m. UTC | #1 
On Mon, Jan 04, 2016 at 10:04:58PM +0100, John Crispin wrote:
> The reset loop logic could run into a endless loop. Lets fix it as
> requested.
> 
> http://lists.infradead.org/pipermail/linux-mtd/2012-September/044240.html

Ah, 3 to 4 years late on the follow up; nice :) Better late than never,
I guess...
diff mbox

Patch

diff --git a/drivers/mtd/nand/xway_nand.c b/drivers/mtd/nand/xway_nand.c
index 548a2b8..c75a2bc 100644
--- a/drivers/mtd/nand/xway_nand.c
+++ b/drivers/mtd/nand/xway_nand.c
@@ -59,16 +59,22 @@  static u32 xway_latchcmd;
 static void xway_reset_chip(struct nand_chip *chip)
 {
 	unsigned long nandaddr = (unsigned long) chip->IO_ADDR_W;
+	unsigned long timeout;
 	unsigned long flags;
 
 	nandaddr &= ~NAND_WRITE_ADDR;
 	nandaddr |= NAND_WRITE_CMD;
 
 	/* finish with a reset */
+	timeout = jiffies + msecs_to_jiffies(20);
+
 	spin_lock_irqsave(&ebu_lock, flags);
 	writeb(NAND_WRITE_CMD_RESET, (void __iomem *) nandaddr);
-	while ((ltq_ebu_r32(EBU_NAND_WAIT) & NAND_WAIT_WR_C) == 0)
-		;
+	do {
+		if ((ltq_ebu_r32(EBU_NAND_WAIT) & NAND_WAIT_WR_C) == 0)
+			break;
+		cond_resched();
+	} while (!time_after_eq(jiffies, timeout));
 	spin_unlock_irqrestore(&ebu_lock, flags);
 }