diff options
Diffstat (limited to 'drivers/platform/x86/surfacepro3_button.c')
| -rw-r--r-- | drivers/platform/x86/surfacepro3_button.c | 53 |
1 files changed, 48 insertions, 5 deletions
diff --git a/drivers/platform/x86/surfacepro3_button.c b/drivers/platform/x86/surfacepro3_button.c index 1b491690ce07..ec515223f654 100644 --- a/drivers/platform/x86/surfacepro3_button.c +++ b/drivers/platform/x86/surfacepro3_button.c @@ -1,14 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * power/home/volume button support for * Microsoft Surface Pro 3/4 tablet. * * Copyright (c) 2015 Intel Corporation. * All rights reserved. - * - * 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; version 2 - * of the License. */ #include <linux/kernel.h> @@ -24,6 +20,12 @@ #define SURFACE_BUTTON_OBJ_NAME "VGBI" #define SURFACE_BUTTON_DEVICE_NAME "Surface Pro 3/4 Buttons" +#define MSHW0040_DSM_REVISION 0x01 +#define MSHW0040_DSM_GET_OMPR 0x02 // get OEM Platform Revision +static const guid_t MSHW0040_DSM_UUID = + GUID_INIT(0x6fd05c69, 0xcde3, 0x49f4, 0x95, 0xed, 0xab, 0x16, 0x65, + 0x49, 0x80, 0x35); + #define SURFACE_BUTTON_NOTIFY_TABLET_MODE 0xc8 #define SURFACE_BUTTON_NOTIFY_PRESS_POWER 0xc6 @@ -146,6 +148,44 @@ static int surface_button_resume(struct device *dev) } #endif +/* + * Surface Pro 4 and Surface Book 2 / Surface Pro 2017 use the same device + * ID (MSHW0040) for the power/volume buttons. Make sure this is the right + * device by checking for the _DSM method and OEM Platform Revision. + * + * Returns true if the driver should bind to this device, i.e. the device is + * either MSWH0028 (Pro 3) or MSHW0040 on a Pro 4 or Book 1. + */ +static bool surface_button_check_MSHW0040(struct acpi_device *dev) +{ + acpi_handle handle = dev->handle; + union acpi_object *result; + u64 oem_platform_rev = 0; // valid revisions are nonzero + + // get OEM platform revision + result = acpi_evaluate_dsm_typed(handle, &MSHW0040_DSM_UUID, + MSHW0040_DSM_REVISION, + MSHW0040_DSM_GET_OMPR, + NULL, ACPI_TYPE_INTEGER); + + /* + * If evaluating the _DSM fails, the method is not present. This means + * that we have either MSHW0028 or MSHW0040 on Pro 4 or Book 1, so we + * should use this driver. We use revision 0 indicating it is + * unavailable. + */ + + if (result) { + oem_platform_rev = result->integer.value; + ACPI_FREE(result); + } + + dev_dbg(&dev->dev, "OEM Platform Revision %llu\n", oem_platform_rev); + + return oem_platform_rev == 0; +} + + static int surface_button_add(struct acpi_device *device) { struct surface_button *button; @@ -158,6 +198,9 @@ static int surface_button_add(struct acpi_device *device) strlen(SURFACE_BUTTON_OBJ_NAME))) return -ENODEV; + if (!surface_button_check_MSHW0040(device)) + return -ENODEV; + button = kzalloc(sizeof(struct surface_button), GFP_KERNEL); if (!button) return -ENOMEM; |
