i2c-s3c2410: sda_delay should be in ns, not clock ticks

The sda_delay field should be specified in ns, not in clock ticks as when using cpufreq we could be changing the bus rate. Signed-off-by: Ben Dooks <[email protected]>
csanz · Apr 7, 2009 · a192f71 · a192f71
1 parent aa11e38
commit a192f71
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Showing 3 changed files with 21 additions and 7 deletions.
diff --git a/arch/arm/plat-s3c/dev-i2c0.c b/arch/arm/plat-s3c/dev-i2c0.c
@@ -52,7 +52,7 @@ static struct s3c2410_platform_i2c default_i2c_data0 __initdata = {
 	.slave_addr	= 0x10,
 	.bus_freq	= 100*1000,
 	.max_freq	= 400*1000,
-	.sda_delay	= S3C2410_IICLC_SDA_DELAY5 | S3C2410_IICLC_FILTER_ON,
+	.sda_delay	= 100,
 };
 
 void __init s3c_i2c0_set_platdata(struct s3c2410_platform_i2c *pd)

diff --git a/arch/arm/plat-s3c/dev-i2c1.c b/arch/arm/plat-s3c/dev-i2c1.c
@@ -49,7 +49,7 @@ static struct s3c2410_platform_i2c default_i2c_data1 __initdata = {
 	.slave_addr	= 0x10,
 	.bus_freq	= 100*1000,
 	.max_freq	= 400*1000,
-	.sda_delay	= S3C2410_IICLC_SDA_DELAY5 | S3C2410_IICLC_FILTER_ON,
+	.sda_delay	= 100,
 };
 
 void __init s3c_i2c1_set_platdata(struct s3c2410_platform_i2c *pd)

diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
@@ -663,6 +663,23 @@ static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got)
 
 	writel(iiccon, i2c->regs + S3C2410_IICCON);
 
+	if (s3c24xx_i2c_is2440(i2c)) {
+		unsigned long sda_delay;
+
+		if (pdata->sda_delay) {
+			sda_delay = (freq / 1000) * pdata->sda_delay;
+			sda_delay /= 1000000;
+			sda_delay = DIV_ROUND_UP(sda_delay, 5);
+			if (sda_delay > 3)
+				sda_delay = 3;
+			sda_delay |= S3C2410_IICLC_FILTER_ON;
+		} else
+			sda_delay = 0;
+
+		dev_dbg(i2c->dev, "IICLC=%08lx\n", sda_delay);
+		writel(sda_delay, i2c->regs + S3C2440_IICLC);
+	}
+
 	return 0;
 }
 
@@ -769,11 +786,8 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
 
 	/* check for s3c2440 i2c controller  */
 
-	if (s3c24xx_i2c_is2440(i2c)) {
-		dev_dbg(i2c->dev, "S3C2440_IICLC=%08x\n", pdata->sda_delay);
-
-		writel(pdata->sda_delay, i2c->regs + S3C2440_IICLC);
-	}
+	if (s3c24xx_i2c_is2440(i2c))
+		writel(0x0, i2c->regs + S3C2440_IICLC);
 
 	return 0;
 }