From ebe8a642f50a0020bed317afcde1f9d2a9da429b Mon Sep 17 00:00:00 2001 From: Kyungmin Park Date: Mon, 27 Sep 2010 16:25:17 +0900 Subject: mtd: OneNAND: S5PC110: Add timeout to prevent the endless loop There's no case timeout but add it for some H/W problem or wrong codes implementation Signed-off-by: Kyungmin Park Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse --- drivers/mtd/onenand/samsung.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/onenand/samsung.c b/drivers/mtd/onenand/samsung.c index 7913a921b08b..b80128036a28 100644 --- a/drivers/mtd/onenand/samsung.c +++ b/drivers/mtd/onenand/samsung.c @@ -535,6 +535,7 @@ static int s5pc110_dma_ops(void *dst, void *src, size_t count, int direction) { void __iomem *base = onenand->dma_addr; int status; + unsigned long timeout; writel(src, base + S5PC110_DMA_SRC_ADDR); writel(dst, base + S5PC110_DMA_DST_ADDR); @@ -552,6 +553,13 @@ static int s5pc110_dma_ops(void *dst, void *src, size_t count, int direction) writel(S5PC110_DMA_TRANS_CMD_TR, base + S5PC110_DMA_TRANS_CMD); + /* + * There's no exact timeout values at Spec. + * In real case it takes under 1 msec. + * So 20 msecs are enough. + */ + timeout = jiffies + msecs_to_jiffies(20); + do { status = readl(base + S5PC110_DMA_TRANS_STATUS); if (status & S5PC110_DMA_TRANS_STATUS_TE) { @@ -559,7 +567,8 @@ static int s5pc110_dma_ops(void *dst, void *src, size_t count, int direction) base + S5PC110_DMA_TRANS_CMD); return -EIO; } - } while (!(status & S5PC110_DMA_TRANS_STATUS_TD)); + } while (!(status & S5PC110_DMA_TRANS_STATUS_TD) && + time_before(jiffies, timeout)); writel(S5PC110_DMA_TRANS_CMD_TDC, base + S5PC110_DMA_TRANS_CMD); -- cgit v1.2.3-59-g8ed1b