From: MyungJoo Ham <myungjoo.ham@samsung.com>
Date: Thu, 30 Sep 2010 13:54:46 +0000 (+0200)
Subject: i2c-s3c2410: fix calculation of SDA line delay
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=7031307aefb6048377385dbb0af2dd43bb0190bb;p=linux-beck.git

i2c-s3c2410: fix calculation of SDA line delay

S3C2440 style I2C controller uses PCLK to calculate the SDA line delay.
The driver wrongly assumed that this delay is calculated from the
frequency that the controller is operating on. This patch fixes this
issue.

Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
---

diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index 72902e0bbfa7..bf831bf81587 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -662,8 +662,8 @@ static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got)
 		unsigned long sda_delay;
 
 		if (pdata->sda_delay) {
-			sda_delay = (freq / 1000) * pdata->sda_delay;
-			sda_delay /= 1000000;
+			sda_delay = clkin * pdata->sda_delay;
+			sda_delay = DIV_ROUND_UP(sda_delay, 1000000);
 			sda_delay = DIV_ROUND_UP(sda_delay, 5);
 			if (sda_delay > 3)
 				sda_delay = 3;