From: Bob Moore <robert.moore@xxxxxxxxx> ACPICA commit 7af00219681ab35ebe57d64a9189fd04a5a026d8 Windows uses a value of 2, and has no plans to ever change this. So, _REV is essentially useless for its primary purpose. Worse, some BIOS vendors have used the difference in _REV values between Windows and ACPICA to indicate which one is running. It has been decided by the ACPI community to deprecate this method, and return 1 for ACPI 1.0 (32-bit integers) and 2 for ACPI 2.0 and greater (both 32-bit and 64-bit integers. ACPICA is changed to reflect this. Link: https://github.com/acpica/acpica/commit/7af00219 Signed-off-by: Bob Moore <robert.moore@xxxxxxxxx> Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx> --- drivers/acpi/acpica/utglobal.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/acpica/utglobal.c b/drivers/acpi/acpica/utglobal.c index 5e8df91..a72685c 100644 --- a/drivers/acpi/acpica/utglobal.c +++ b/drivers/acpi/acpica/utglobal.c @@ -102,12 +102,19 @@ const struct acpi_predefined_names acpi_gbl_pre_defined_names[] = { {"_SB_", ACPI_TYPE_DEVICE, NULL}, {"_SI_", ACPI_TYPE_LOCAL_SCOPE, NULL}, {"_TZ_", ACPI_TYPE_DEVICE, NULL}, - {"_REV", ACPI_TYPE_INTEGER, (char *)ACPI_CA_SUPPORT_LEVEL}, + /* + * March, 2015: + * The _REV object is in the process of being deprecated, because + * other ACPI implementations permanently return 2. Thus, it + * has little or no value. Return 2 for compatibility with + * other ACPI implementations. + */ + {"_REV", ACPI_TYPE_INTEGER, ACPI_CAST_PTR(char, 2)}, {"_OS_", ACPI_TYPE_STRING, ACPI_OS_NAME}, - {"_GL_", ACPI_TYPE_MUTEX, (char *)1}, + {"_GL_", ACPI_TYPE_MUTEX, ACPI_CAST_PTR(char, 1)}, #if !defined (ACPI_NO_METHOD_EXECUTION) || defined (ACPI_CONSTANT_EVAL_ONLY) - {"_OSI", ACPI_TYPE_METHOD, (char *)1}, + {"_OSI", ACPI_TYPE_METHOD, ACPI_CAST_PTR(char, 1)}, #endif /* Table terminator */ -- 1.7.10 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html