mfd: tps65090: add DT support for tps65090

Add device tree support for the TI PMIC TPS65090.
The device can be registered through platform or DT.

Add device tree binding document for this device.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/tps65090.c b/drivers/mfd/tps65090.c
index 8d12a8e..b496545 100644
--- a/drivers/mfd/tps65090.c
+++ b/drivers/mfd/tps65090.c
@@ -25,6 +25,8 @@
 #include <linux/i2c.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/tps65090.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/err.h>
 
 #define NUM_INT_REG 2
@@ -148,18 +150,31 @@
 	.volatile_reg = is_volatile_reg,
 };
 
+#ifdef CONFIG_OF
+static const struct of_device_id tps65090_of_match[] = {
+	{ .compatible = "ti,tps65090",},
+	{},
+};
+MODULE_DEVICE_TABLE(of, tps65090_of_match);
+#endif
+
 static int tps65090_i2c_probe(struct i2c_client *client,
 					const struct i2c_device_id *id)
 {
 	struct tps65090_platform_data *pdata = client->dev.platform_data;
+	int irq_base = 0;
 	struct tps65090 *tps65090;
 	int ret;
 
-	if (!pdata) {
-		dev_err(&client->dev, "tps65090 requires platform data\n");
+	if (!pdata && !client->dev.of_node) {
+		dev_err(&client->dev,
+			"tps65090 requires platform data or of_node\n");
 		return -EINVAL;
 	}
 
+	if (pdata)
+		irq_base = pdata->irq_base;
+
 	tps65090 = devm_kzalloc(&client->dev, sizeof(*tps65090), GFP_KERNEL);
 	if (!tps65090) {
 		dev_err(&client->dev, "mem alloc for tps65090 failed\n");
@@ -178,7 +193,7 @@
 
 	if (client->irq) {
 		ret = regmap_add_irq_chip(tps65090->rmap, client->irq,
-			IRQF_ONESHOT | IRQF_TRIGGER_LOW, pdata->irq_base,
+			IRQF_ONESHOT | IRQF_TRIGGER_LOW, irq_base,
 			&tps65090_irq_chip, &tps65090->irq_data);
 			if (ret) {
 				dev_err(&client->dev,
@@ -247,6 +262,7 @@
 	.driver	= {
 		.name	= "tps65090",
 		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(tps65090_of_match),
 		.pm	= &tps65090_pm_ops,
 	},
 	.probe		= tps65090_i2c_probe,