linux-kernel - [PATCH 1/2] spi/spi_s3c64xx: Fix timeout handling in wait_for

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1283873872-8633-1-git-send-email-broonie@opensource.wolfsonmicro.com>
Date:	Tue,  7 Sep 2010 16:37:51 +0100
From:	Mark Brown <broonie@...nsource.wolfsonmicro.com>
To:	Grant Likely <grant.likely@...retlab.ca>,
	David Brownell <dbrownell@...rs.sourceforge.net>,
	Jassi Brar <jassi.brar@...sung.com>
Cc:	spi-devel-general@...ts.sourceforge.net,
	linux-kernel@...r.kernel.org,
	Mark Brown <broonie@...nsource.wolfsonmicro.com>
Subject: [PATCH 1/2] spi/spi_s3c64xx: Fix timeout handling in wait_for_xfer()

In wait_for_xfer() for PIO transfer we are using val as both a
counter variable to track the number of spins we've waited for
completion and the value we read from the controller, causing
us to fail to ever actually notice the timeout. Fix this by using
a separate value to hold the register readback.

Also warn when we hit the timeout.

Signed-off-by: Mark Brown <broonie@...nsource.wolfsonmicro.com>
---
 drivers/spi/spi_s3c64xx.c |   11 +++++++----
 1 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spi_s3c64xx.c b/drivers/spi/spi_s3c64xx.c
index 6e48ea9..03b28e4 100644
--- a/drivers/spi/spi_s3c64xx.c
+++ b/drivers/spi/spi_s3c64xx.c
@@ -321,7 +321,7 @@ static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
 {
 	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
 	void __iomem *regs = sdd->regs;
-	unsigned long val;
+	unsigned long val, reg;
 	int ms;
 
 	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
@@ -333,13 +333,16 @@ static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
 		val = wait_for_completion_timeout(&sdd->xfer_completion, val);
 	} else {
 		val = msecs_to_loops(ms);
+
 		do {
-			val = readl(regs + S3C64XX_SPI_STATUS);
-		} while (RX_FIFO_LVL(val, sci) < xfer->len && --val);
+			reg = readl(regs + S3C64XX_SPI_STATUS);
+		} while (RX_FIFO_LVL(reg, sci) < xfer->len && --val);
 	}
 
-	if (!val)
+	if (!val) {
+		dev_warn(&sdd->pdev->dev, "Transfer timeout\n");
 		return -EIO;
+	}
 
 	if (dma_mode) {
 		u32 status;
-- 
1.7.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/