i2c-designware: Move retriveving the clock speed out of core code.

The clock frequecy supplied to the IP core is specific to a single
instance of the driver.  This patch makes it possible to have multiple
Designware I2C cores in the system possibly running at different core
frequencies.

Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

drivers/i2c/busses/i2c-designware-platdrv.c

@@ -43,6 +43,10 @@ static struct i2c_algorithm i2c_dw_algo = {
 	.master_xfer	= i2c_dw_xfer,
 	.functionality	= i2c_dw_func,
 };
+static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
+{
+	return clk_get_rate(dev->clk)/1000;
+}
 
 static int __devinit dw_i2c_probe(struct platform_device *pdev)
 {
@@ -84,6 +88,8 @@ static int __devinit dw_i2c_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, dev);
 
 	dev->clk = clk_get(&pdev->dev, NULL);
+	dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
+
 	if (IS_ERR(dev->clk)) {
 		r = -ENODEV;
 		goto err_free_mem;