hwmon: (ina2xx) Add OF device ID table

The driver doesn't have a struct of_device_id table but supported devices
are registered via Device Trees. This is working on the assumption that a
I2C device registered via OF will always match a legacy I2C device ID and
that the MODALIAS reported will always be of the form i2c:<device>.

But this could change in the future so the correct approach is to have an
OF device ID table if the devices are registered via OF.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/ina2xx.c

@@ -34,6 +34,7 @@
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
 #include <linux/jiffies.h>
+#include <linux/of_device.h>
 #include <linux/of.h>
 #include <linux/delay.h>
 #include <linux/util_macros.h>
@@ -424,13 +425,19 @@ static int ina2xx_probe(struct i2c_client *client,
 	struct device *hwmon_dev;
 	u32 val;
 	int ret, group = 0;
+	enum ina2xx_ids chip;
+
+	if (client->dev.of_node)
+		chip = (enum ina2xx_ids)of_device_get_match_data(&client->dev);
+	else
+		chip = id->driver_data;
 
 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;
 
 	/* set the device type */
-	data->config = &ina2xx_config[id->driver_data];
+	data->config = &ina2xx_config[chip];
 
 	if (of_property_read_u32(dev->of_node, "shunt-resistor", &val) < 0) {
 		struct ina2xx_platform_data *pdata = dev_get_platdata(dev);
@@ -487,9 +494,35 @@ static const struct i2c_device_id ina2xx_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, ina2xx_id);
 
+static const struct of_device_id ina2xx_of_match[] = {
+	{
+		.compatible = "ti,ina219",
+		.data = (void *)ina219
+	},
+	{
+		.compatible = "ti,ina220",
+		.data = (void *)ina219
+	},
+	{
+		.compatible = "ti,ina226",
+		.data = (void *)ina226
+	},
+	{
+		.compatible = "ti,ina230",
+		.data = (void *)ina226
+	},
+	{
+		.compatible = "ti,ina231",
+		.data = (void *)ina226
+	},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, ina2xx_of_match);
+
 static struct i2c_driver ina2xx_driver = {
 	.driver = {
 		.name	= "ina2xx",
+		.of_match_table = of_match_ptr(ina2xx_of_match),
 	},
 	.probe		= ina2xx_probe,
 	.id_table	= ina2xx_id,