backlight: Allow properties to be passed at registration

Values such as max_brightness should be set before backlights are
registered, but the current API doesn't allow that. Add a parameter to
backlight_device_register and update drivers to ensure that they
set this correctly.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
diff --git a/drivers/video/backlight/da903x_bl.c b/drivers/video/backlight/da903x_bl.c
index 74cdc64..686e4a7 100644
--- a/drivers/video/backlight/da903x_bl.c
+++ b/drivers/video/backlight/da903x_bl.c
@@ -105,6 +105,7 @@
 	struct da9034_backlight_pdata *pdata = pdev->dev.platform_data;
 	struct da903x_backlight_data *data;
 	struct backlight_device *bl;
+	struct backlight_properties props;
 	int max_brightness;
 
 	data = kzalloc(sizeof(*data), GFP_KERNEL);
@@ -134,15 +135,15 @@
 		da903x_write(data->da903x_dev, DA9034_WLED_CONTROL2,
 				DA9034_WLED_ISET(pdata->output_current));
 
-	bl = backlight_device_register(pdev->name, data->da903x_dev,
-			data, &da903x_backlight_ops);
+	props.max_brightness = max_brightness;
+	bl = backlight_device_register(pdev->name, data->da903x_dev, data,
+				       &da903x_backlight_ops, &props);
 	if (IS_ERR(bl)) {
 		dev_err(&pdev->dev, "failed to register backlight\n");
 		kfree(data);
 		return PTR_ERR(bl);
 	}
 
-	bl->props.max_brightness = max_brightness;
 	bl->props.brightness = max_brightness;
 
 	platform_set_drvdata(pdev, bl);