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>

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/usb/misc/appledisplay.c b/drivers/usb/misc/appledisplay.c
index 4d2952f1fb13..3adab041355a 100644
--- a/drivers/usb/misc/appledisplay.c
+++ b/drivers/usb/misc/appledisplay.c
@@ -202,6 +202,7 @@ static void appledisplay_work(struct work_struct *work)
 static int appledisplay_probe(struct usb_interface *iface,
         const struct usb_device_id *id)
 {
+        struct backlight_properties props;
         struct appledisplay *pdata;
         struct usb_device *udev = interface_to_usbdev(iface);
         struct usb_host_interface *iface_desc;
@@ -279,16 +280,16 @@ static int appledisplay_probe(struct usb_interface *iface,
         /* Register backlight device */
         snprintf(bl_name, sizeof(bl_name), "appledisplay%d",
                 atomic_inc_return(&count_displays) - 1);
+        memset(&props, 0, sizeof(struct backlight_properties));
+        props.max_brightness = 0xff;
         pdata->bd = backlight_device_register(bl_name, NULL, pdata,
-                                                &appledisplay_bl_data);
+                                              &appledisplay_bl_data, &props);
         if (IS_ERR(pdata->bd)) {
                 dev_err(&iface->dev, "Backlight registration failed\n");
                 retval = PTR_ERR(pdata->bd);
                 goto error;
         }
 
-        pdata->bd->props.max_brightness = 0xff;
-
         /* Try to get brightness */
         brightness = appledisplay_bl_get_brightness(pdata->bd);