[media] dw2102: store i2c client for tuner into dw2102_state

Prepare the dw2102 driver for tuner drivers that are implemented as I2C
drivers (such as m88ts2022). The I2C client is stored in to the state
and released at disconnect.
Signed-off-by: Olli Salonen <olli.salonen@iki.fi>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/usb/dvb-usb/dw2102.c

@@ -114,6 +114,7 @@
 
 struct dw2102_state {
 	u8 initialized;
+	struct i2c_client *i2c_client_tuner;
 	int (*old_set_voltage)(struct dvb_frontend *f, fe_sec_voltage_t v);
 };
 
@@ -2138,10 +2139,26 @@ static int dw2102_probe(struct usb_interface *intf,
 	return -ENODEV;
 }
 
+static void dw2102_disconnect(struct usb_interface *intf)
+{
+	struct dvb_usb_device *d = usb_get_intfdata(intf);
+	struct dw2102_state *st = (struct dw2102_state *)d->priv;
+	struct i2c_client *client;
+
+	/* remove I2C client for tuner */
+	client = st->i2c_client_tuner;
+	if (client) {
+		module_put(client->dev.driver->owner);
+		i2c_unregister_device(client);
+	}
+
+	dvb_usb_device_exit(intf);
+}
+
 static struct usb_driver dw2102_driver = {
 	.name = "dw2102",
 	.probe = dw2102_probe,
-	.disconnect = dvb_usb_device_exit,
+	.disconnect = dw2102_disconnect,
 	.id_table = dw2102_table,
 };