mfd: palmas: Add device tree handling to mfd

Add device tree handling to the palmas MFD. This takes the values
that can be set from platform data from the device tree nodes instead.

Signed-off-by: Graeme Gregory <gg@slimlogic.co.uk>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/palmas.c b/drivers/mfd/palmas.c
index 7c1a194..4f8d6e6 100644
--- a/drivers/mfd/palmas.c
+++ b/drivers/mfd/palmas.c
@@ -23,6 +23,7 @@
 #include <linux/err.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/palmas.h>
+#include <linux/of_platform.h>
 
 enum palmas_ids {
 	PALMAS_PMIC_ID,
@@ -246,17 +247,56 @@
 			PALMAS_INT1_MASK),
 };
 
+static void __devinit palmas_dt_to_pdata(struct device_node *node,
+		struct palmas_platform_data *pdata)
+{
+	int ret;
+	u32 prop;
+
+	ret = of_property_read_u32(node, "ti,mux_pad1", &prop);
+	if (!ret) {
+		pdata->mux_from_pdata = 1;
+		pdata->pad1 = prop;
+	}
+
+	ret = of_property_read_u32(node, "ti,mux_pad2", &prop);
+	if (!ret) {
+		pdata->mux_from_pdata = 1;
+		pdata->pad2 = prop;
+	}
+
+	/* The default for this register is all masked */
+	ret = of_property_read_u32(node, "ti,power_ctrl", &prop);
+	if (!ret)
+		pdata->power_ctrl = prop;
+	else
+		pdata->power_ctrl = PALMAS_POWER_CTRL_NSLEEP_MASK |
+					PALMAS_POWER_CTRL_ENABLE1_MASK |
+					PALMAS_POWER_CTRL_ENABLE2_MASK;
+}
+
 static int __devinit palmas_i2c_probe(struct i2c_client *i2c,
 			    const struct i2c_device_id *id)
 {
 	struct palmas *palmas;
 	struct palmas_platform_data *pdata;
+	struct device_node *node = i2c->dev.of_node;
 	int ret = 0, i;
 	unsigned int reg, addr;
 	int slave;
 	struct mfd_cell *children;
 
 	pdata = dev_get_platdata(&i2c->dev);
+
+	if (node && !pdata) {
+		pdata = devm_kzalloc(&i2c->dev, sizeof(*pdata), GFP_KERNEL);
+
+		if (!pdata)
+			return -ENOMEM;
+
+		palmas_dt_to_pdata(node, pdata);
+	}
+
 	if (!pdata)
 		return -EINVAL;
 
@@ -379,6 +419,18 @@
 	if (ret)
 		goto err_irq;
 
+	/*
+	 * If we are probing with DT do this the DT way and return here
+	 * otherwise continue and add devices using mfd helpers.
+	 */
+	if (node) {
+		ret = of_platform_populate(node, NULL, NULL, &i2c->dev);
+		if (ret < 0)
+			goto err_irq;
+		else
+			return ret;
+	}
+
 	children = kmemdup(palmas_children, sizeof(palmas_children),
 			   GFP_KERNEL);
 	if (!children) {