platform/x86: mxm-wmi: fix memleak in mxm_wmi_call_mx[ds|mx]()

The ACPI buffer memory (out.pointer) returned by wmi_evaluate_method()
is not freed after the call, so it leads to memory leak.

The method results in ACPI buffer is not used, so just pass NULL to
wmi_evaluate_method() which fixes the memory leak.

Fixes: 99b38b4acc0d ("platform/x86: add MXM WMI driver.")
Signed-off-by: Yu Liao <liaoyu15@huawei.com>
Link: https://lore.kernel.org/r/20221129011101.2042315-1-liaoyu15@huawei.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

platform/x86: mxm-wmi: Evaluate wmi method with instance number 0x0

According to MXM 2.1 specification, there is the only one instance of the
WMI GUID F6CB5C3C-9CAE-4EBD-B577-931EA32A2CC0 and so it is instance 0x0.

MXM 2.1 specification:
https://lekensteyn.nl/files/docs/mxm-2.1-software-spec.pdf

_WDG dump:
// Methods GUID {F6CB5C3C-9CAE-4EBD-B577-931EA32A2CC0}
0x3C, 0x5C, 0xCB, 0xF6, 0xAE, 0x9C, 0xBD, 0x4E, 0xB5, 0x77, 0x93,
0x1E, 0xA3, 0x2A, 0x2C, 0xC0,
0x4D, 0x58, // Object ID "MX" = method "WMMX"
1, // Instance Count
0x02, // Flags (WMIACPI_REGFLAG_METHOD)

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

drivers: platform: Include appropriate header file in mxm-wmi.c

This patch includes appropriate header file linux/mxm-wmi.h in
x86/mxm-wmi.c because functions mxm_wmi_call_mxds(), mxm_wmi_call_mxmx()
and mxm_wmi_supported() have their prototype declaration in
linux/mxm-wmi.h.

Thus, it also eliminates the following warnings in x86/mxm-wmi.c:
drivers/platform/x86/mxm-wmi.c:43:5: warning: no previous prototype for ‘mxm_wmi_call_mxds’ [-Wmissing-prototypes]
drivers/platform/x86/mxm-wmi.c:68:5: warning: no previous prototype for ‘mxm_wmi_call_mxmx’ [-Wmissing-prototypes]
drivers/platform/x86/mxm-wmi.c:93:6: warning: no previous prototype for ‘mxm_wmi_supported’ [-Wmissing-prototypes]

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>

ACPI: Clean up inclusions of ACPI header files

Replace direct inclusions of <acpi/acpi.h>, <acpi/acpi_bus.h> and
<acpi/acpi_drivers.h>, which are incorrect, with <linux/acpi.h>
inclusions and remove some inclusions of those files that aren't
necessary.

First of all, <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h>
should not be included directly from any files that are built for
CONFIG_ACPI unset, because that generally leads to build warnings about
undefined symbols in !CONFIG_ACPI builds. For CONFIG_ACPI set,
<linux/acpi.h> includes those files and for CONFIG_ACPI unset it
provides stub ACPI symbols to be used in that case.

Second, there are ordering dependencies between those files that always
have to be met. Namely, it is required that <acpi/acpi_bus.h> be included
prior to <acpi/acpi_drivers.h> so that the acpi_pci_root declarations the
latter depends on are always there. And <acpi/acpi.h> which provides
basic ACPICA type declarations should always be included prior to any other
ACPI headers in CONFIG_ACPI builds. That also is taken care of including
<linux/acpi.h> as appropriate.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci stuff)
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> (Xen stuff)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

mxm/wmi: add MXMX interface entry point.

The MXMX method appears to be a mutex of some sort.

Signed-off-by: Dave Airlie <airlied@redhat.com>

platform/x86: add MXM WMI driver.

MXM is a laptop graphics card form-factor + interface specification,
this adds an initial stub driver to talk to the MXM WMI interface.

The only method used is the MUX switching method needed to do switchable
graphics on the nvidia chipsets.

Signed-off-by: Dave Airlie <airlied@redhat.com>
Acked-by: Matthew Garrett <mjg@redhat.com>