Properly return backlight registration error to parent.
Mark struct backlight_ops as const.
Signed-off-by: NBruno Prémont <bonbons@linux-vserver.org>
Reviewed-by: NAnisse Astier <anisse@astier.eu>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

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: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

When acpi_evaluate_object() is passed ACPI_ALLOCATE_BUFFER,
the caller must kfree the returned buffer if AE_OK is returned.

The callers of wmi_get_event_data() pass ACPI_ALLOCATE_BUFFER,
and thus must check its return value before accessing
or kfree() on the buffer.
Signed-off-by: NLen Brown <len.brown@intel.com>

Emphasize that that wmi_install_notify_handler() returns an acpi_status
rather than -errno by by testing ACPI_SUCCESS(), ACPI_FAILURE().

No functional change in this patch, but this confusion caused a bug in dell-wmi.
Signed-off-by: NLen Brown <len.brown@intel.com>

Now that we have WMI autoloading
the DMI matching is not needed anymore.
Signed-off-by: NThomas Renninger <trenn@suse.de>
Acked-by: NCarlos Corbacho <carlos@strangeworlds.co.uk>
Acked-by: NAnisse Astier <anisse@astier.eu>
Signed-off-by: NLen Brown <len.brown@intel.com>

Now depends on BACKLIGHT_CLASS_DEVICE.
Driver will return an error if it can't get actual backlight value
Fix remapping of brightness keys when backlight is not controlled by ACPI.
Signed-off-by: NAnisse Astier <anisse@astier.eu>
Signed-off-by: NLen Brown <len.brown@intel.com>

Signed-off-by: NAnisse Astier <anisse@astier.eu>
Signed-off-by: NLen Brown <len.brown@intel.com>

Signed-off-by: NAnisse Astier <anisse@astier.eu>
Signed-off-by: NLen Brown <len.brown@intel.com>

Signed-off-by: NAnisse Astier <anisse@astier.eu>
Signed-off-by: NLen Brown <len.brown@intel.com>

Rely on DYNAMIC_DEBUG instead if needed
Signed-off-by: NAnisse Astier <anisse@astier.eu>
Signed-off-by: NLen Brown <len.brown@intel.com>

There should be less code duplication with usage of gotos
Driver won't load if there's no hardware to control
Safer error handling at input driver allocation
Signed-off-by: NAnisse Astier <anisse@astier.eu>
Signed-off-by: NLen Brown <len.brown@intel.com>

Signed-off-by: NAnisse Astier <anisse@astier.eu>
Signed-off-by: NLen Brown <len.brown@intel.com>

This driver serves backlight (including switching) and volume up/down
keys for MSI machines providing a specific wmi interface:
551A1F84-FBDD-4125-91DB-3EA8F44F1D45
B6F3EEF2-3D2F-49DC-9DE3-85BCE18C62F2
Signed-off-by: NThomas Renninger <trenn@suse.de>
CC: Carlos Corbacho <carlos@strangeworlds.co.uk>
CC: Matthew Garrett <mjg59@srcf.ucam.org>
Tested-by: NMatt Chen <machen@novell.com>
Reviewed-by: NAnisse Astier <anisse@astier.eu>
Signed-off-by: NLen Brown <len.brown@intel.com>