i2c-nomadik: fixup bus delays
authorLinus Walleij <linus.walleij@stericsson.com>
Thu, 23 Sep 2010 07:04:11 +0000 (09:04 +0200)
committerBen Dooks <ben-linux@fluff.org>
Mon, 25 Oct 2010 01:40:48 +0000 (02:40 +0100)
We were missing a transfer delay in one execution path leading to
hangs and the bus timeout was too low leading to errors under
stress tests.

Acked-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Signed-off-by: Sundar R Iyer <sundar.iyer@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
drivers/i2c/busses/i2c-nomadik.c

index e461de7..c9fffd0 100644 (file)
 /* maximum threshold value */
 #define MAX_I2C_FIFO_THRESHOLD 15
 
+/* per-transfer delay, required for the hardware to stabilize */
+#define I2C_DELAY              150
+
 enum i2c_status {
        I2C_NOP,
        I2C_ON_GOING,
@@ -118,7 +121,7 @@ enum i2c_operation {
 };
 
 /* controller response timeout in ms */
-#define I2C_TIMEOUT_MS 500
+#define I2C_TIMEOUT_MS 2000
 
 /**
  * struct i2c_nmk_client - client specific data
@@ -267,6 +270,7 @@ static int init_hw(struct nmk_i2c_dev *dev)
 
        clk_disable(dev->clk);
 
+       udelay(I2C_DELAY);
        return 0;
 }
 
@@ -599,7 +603,7 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap,
                        clk_disable(dev->clk);
                        return status;
                }
-               mdelay(1);
+               udelay(I2C_DELAY);
        }
        clk_disable(dev->clk);