From cd97f39b7cdf1c8a9c9f52865eec795b7f0c811d Mon Sep 17 00:00:00 2001
From: Jean Delvare <khali@linux-fr.org>
Date: Tue, 24 Feb 2009 19:19:49 +0100
Subject: i2c-dev: Clarify the unit of ioctl I2C_TIMEOUT

The unit in which user-space can set the bus timeout value is jiffies
for historical reasons (back when HZ was always 100.) This is however
not good because user-space doesn't know how long a jiffy lasts. The
timeout value should instead be set in a fixed time unit. Given the
original value of HZ, this unit should be 10 ms, for compatibility.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
---
 include/linux/i2c-dev.h | 2 +-
 include/linux/i2c.h     | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

(limited to 'include')

diff --git a/include/linux/i2c-dev.h b/include/linux/i2c-dev.h
index 311315b56b61..fd53bfd26470 100644
--- a/include/linux/i2c-dev.h
+++ b/include/linux/i2c-dev.h
@@ -33,7 +33,7 @@
  */
 #define I2C_RETRIES	0x0701	/* number of times a device address should
 				   be polled when not acknowledging */
-#define I2C_TIMEOUT	0x0702	/* set timeout in jiffies - call with int */
+#define I2C_TIMEOUT	0x0702	/* set timeout in units of 10 ms */
 
 /* NOTE: Slave address is 7 or 10 bits, but 10-bit addresses
  * are NOT supported! (due to code brokenness)
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index fcfbfea3af72..c86c3b07604c 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -361,7 +361,7 @@ struct i2c_adapter {
 	struct mutex bus_lock;
 	struct mutex clist_lock;
 
-	int timeout;
+	int timeout;			/* in jiffies */
 	int retries;
 	struct device dev;		/* the adapter device */
 
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