dell-wmi: sys_init_module: 'dell_wmi'->init suspiciously returned 21, it should follow 0/-E convention

wmi_install_notify_handler() returns an acpi_error,
but dell_wmi_init() needs return a -errno style error.
Signed-off-by: NLen Brown <len.brown@intel.com>
Tested-by: NPaul Rolland <rol@as2917.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There is no point in having the driver loaded in memory if we fail
to locate particular WMI GUID.
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>
Acked-by: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

These function allocate an acpi object by calling wmi_get_event_data, which
then calls acpi_evaluate_object, and it is not freed afterwards.

And kernel doc is fixed for parameters of wmi_get_event_data.
Signed-off-by: NAnisse Astier <anisse@astier.eu>
Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Acked-by: NCarlos Corbacho <carlos@strangeworlds.co.uk>
Signed-off-by: NLen Brown <len.brown@intel.com>

Newer Dell systems support HotKey features differently from legacy
systems.  A new vendor specifc HotKey SMBIOS table (Type 0xB2) is
defined. This table contains a mapping between scancode and the
corresponding predefined keyfunction ( i.e. keycode).. Also, a new
ACPI-WMI event type (called KeyIDList) with a value of 0x0010 is
defined. Any BIOS containing 0xB2 table will send hotkey notifications
using KeyIDList event.

This is Rezwanul's patch, updated to ensure that brightness events are
not sent if the backlight is controlled via ACPI and with the default
keycode for the display output switching altered to match desktop
expectations.
Signed-off-by: NRezwanul Kabir <Rezwanul_Kabir@dell.com>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

There's no point in generating kernel messages if we didn't receive a
parsable keyboard event - only do so if there appeared to be a scancode.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

Upcoming Dell hardware will send more keyboard events via WMI.  Add
support for them.
Signed-off-by: NMario Limonciello <mario_limonciello@dell.com>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

In debugging with some future machines that actually contain BIOS level
support for dell-wmi, I've determined that the upper half of the data that
comes back from wmi_get_event_data may sometimes contain extra information
that isn't currently relevant when pulling scan codes out of the data.
This causes dell-wmi to improperly respond to these events.
Signed-off-by: NMario Limonciello <mario_limonciello@dell.com>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add a WMI driver for Dell laptops. Currently it does nothing but send a
generic input event when a button with a picture of a battery on it is
pressed, but maybe other uses will appear over time.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>