backlight: add backlight type

There may be multiple ways of controlling the backlight on a given
machine.  Allow drivers to expose the type of interface they are
providing, making it possible for userspace to make appropriate policy
decisions.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Airlie <airlied@linux.ie>
Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 90f8f7676d1f..a9eec8c95a1f 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -795,6 +795,7 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
                 count++;
 
                 memset(&props, 0, sizeof(struct backlight_properties));
+                props.type = BACKLIGHT_FIRMWARE;
                 props.max_brightness = device->brightness->count - 3;
                 device->backlight = backlight_device_register(name, NULL, device,
                                                               &acpi_backlight_ops,