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 <[email protected]> Signed-off-by: Kyungmin Park <[email protected]> Signed-off-by: Marek Szyprowski <[email protected]> Signed-off-by: Ben Dooks <[email protected]>
yshchan · Sep 30, 2010 · 7031307 · 7031307
1 parent 4bba0fd
commit 7031307
Showing 1 changed file with 2 additions and 2 deletions.
diff --git 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;