lkml.org 
[lkml]   [2015]   [Apr]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 24/31] ACPICA: Permanently set _REV to the value '2'.
Date
From: Bob Moore <robert.moore@intel.com>

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@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
---
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


\
 
 \ /
  Last update: 2015-04-13 06:21    [W:0.084 / U:0.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site