i2c: rcar: refactor probe function a little

The probe function is a little bit messy, something here, something
there. Rework it so that there is some order: first init the private
structure, then the adapter, then do HW init. This also allows us to
remove the device argument of the clock calculation function, because it
now can be deduced from the private structure. Also, shorten some lines
where possible. This is a preparation for further refactoring.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

drivers/i2c/busses/i2c-rcar.c

@@ -162,15 +162,11 @@ static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv)
 	return -EBUSY;
 }
 
-static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv,
-				    u32 bus_speed,
-				    struct device *dev)
+static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv, u32 bus_speed)
 {
-	u32 scgd, cdf;
-	u32 round, ick;
-	u32 scl;
-	u32 cdf_width;
+	u32 scgd, cdf, round, ick, scl, cdf_width;
 	unsigned long rate;
+	struct device *dev = rcar_i2c_priv_to_dev(priv);
 
 	switch (priv->devtype) {
 	case I2C_RCAR_GEN1:
@@ -610,21 +606,7 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 	if (IS_ERR(priv->io))
 		return PTR_ERR(priv->io);
 
-	bus_speed = 100000; /* default 100 kHz */
-	of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed);
-
 	priv->devtype = (enum rcar_i2c_type)of_match_device(rcar_i2c_dt_ids, dev)->data;
-
-	pm_runtime_enable(dev);
-	pm_runtime_get_sync(dev);
-	ret = rcar_i2c_clock_calculate(priv, bus_speed, dev);
-	if (ret < 0)
-		goto out_pm_put;
-
-	rcar_i2c_init(priv);
-	pm_runtime_put(dev);
-
-	irq = platform_get_irq(pdev, 0);
 	init_waitqueue_head(&priv->wait);
 
 	adap = &priv->adap;
@@ -637,8 +619,20 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 	i2c_set_adapdata(adap, priv);
 	strlcpy(adap->name, pdev->name, sizeof(adap->name));
 
-	ret = devm_request_irq(dev, irq, rcar_i2c_irq, 0,
-			       dev_name(dev), priv);
+	bus_speed = 100000; /* default 100 kHz */
+	of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed);
+
+	pm_runtime_enable(dev);
+	pm_runtime_get_sync(dev);
+	ret = rcar_i2c_clock_calculate(priv, bus_speed);
+	if (ret < 0)
+		goto out_pm_put;
+
+	rcar_i2c_init(priv);
+	pm_runtime_put(dev);
+
+	irq = platform_get_irq(pdev, 0);
+	ret = devm_request_irq(dev, irq, rcar_i2c_irq, 0, dev_name(dev), priv);
 	if (ret < 0) {
 		dev_err(dev, "cannot get irq %d\n", irq);
 		goto out_pm_disable;