rtc: abx80x: Add Device Tree matching table

Enable automatic loading of the module when a Device Tree overlay
specifies a device supported by this driver.
Signed-off-by: Kevin P. Fleming <kevin+linux@km6g.us>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200528114617.166587-1-kevin+linux@km6g.us

drivers/rtc/rtc-abx80x.c

@@ -13,6 +13,7 @@
 #include <linux/bcd.h>
 #include <linux/i2c.h>
 #include <linux/module.h>
+#include <linux/of_device.h>
 #include <linux/rtc.h>
 #include <linux/watchdog.h>
 
@@ -863,9 +864,57 @@ static const struct i2c_device_id abx80x_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, abx80x_id);
 
+#ifdef CONFIG_OF
+static const struct of_device_id abx80x_of_match[] = {
+	{
+		.compatible = "abracon,abx80x",
+		.data = (void *)ABX80X
+	},
+	{
+		.compatible = "abracon,ab0801",
+		.data = (void *)AB0801
+	},
+	{
+		.compatible = "abracon,ab0803",
+		.data = (void *)AB0803
+	},
+	{
+		.compatible = "abracon,ab0804",
+		.data = (void *)AB0804
+	},
+	{
+		.compatible = "abracon,ab0805",
+		.data = (void *)AB0805
+	},
+	{
+		.compatible = "abracon,ab1801",
+		.data = (void *)AB1801
+	},
+	{
+		.compatible = "abracon,ab1803",
+		.data = (void *)AB1803
+	},
+	{
+		.compatible = "abracon,ab1804",
+		.data = (void *)AB1804
+	},
+	{
+		.compatible = "abracon,ab1805",
+		.data = (void *)AB1805
+	},
+	{
+		.compatible = "microcrystal,rv1805",
+		.data = (void *)RV1805
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(of, abx80x_of_match);
+#endif
+
 static struct i2c_driver abx80x_driver = {
 	.driver		= {
 		.name	= "rtc-abx80x",
+		.of_match_table = of_match_ptr(abx80x_of_match),
 	},
 	.probe		= abx80x_probe,
 	.id_table	= abx80x_id,