aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/acpi/reboot.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2008-10-23 13:20:36 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2008-10-23 13:20:36 -0400
commit765426e8ee4c0ab2bc9d44951f4865b8494cdbd0 (patch)
tree2b46ab8953eff175c8d3474a9754c1ab1394e4de /drivers/acpi/reboot.c
parent36ec891895020f3bc9953c8b11d079c6d77d76bd (diff)
parent898b054f3eec5921320ae8614b5bdd7b07ea5b43 (diff)
Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (123 commits) dock: make dock driver not a module ACPI: fix ia64 build warning ACPI: hack around sysfs warning with link order ACPI suspend: fix build warning when CONFIG_ACPI_SLEEP=n intel_menlo: fix build warning panasonic-laptop: fix build ACPICA: Update version to 20080926 ACPICA: Add support for zero-length buffer-to-string conversions ACPICA: New: Validation for predefined ACPI methods/objects ACPICA: Fix for implicit return compatibility ACPICA: Fixed a couple memory leaks associated with "implicit return" ACPICA: Optimize buffer allocation procedure ACPICA: Fix possible memory leak, error exit path ACPICA: Fix fault after mem allocation failure in AML parser ACPICA: Remove unused ACPI register bit definition ACPICA: Update version to 20080829 ACPICA: Fix possible memory leak in acpi_ns_get_external_pathname ACPICA: Cleanup for internal Reference Object ACPICA: Update comments - no functional changes ACPICA: Update for Reference ACPI_OPERAND_OBJECT ...
Diffstat (limited to 'drivers/acpi/reboot.c')
-rw-r--r--drivers/acpi/reboot.c25
1 files changed, 22 insertions, 3 deletions
diff --git a/drivers/acpi/reboot.c b/drivers/acpi/reboot.c
index a6b662c00b67..755baf2ca70a 100644
--- a/drivers/acpi/reboot.c
+++ b/drivers/acpi/reboot.c
@@ -15,9 +15,28 @@ void acpi_reboot(void)
15 15
16 rr = &acpi_gbl_FADT.reset_register; 16 rr = &acpi_gbl_FADT.reset_register;
17 17
18 /* Is the reset register supported? */ 18 /*
19 if (!(acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER) || 19 * Is the ACPI reset register supported?
20 rr->bit_width != 8 || rr->bit_offset != 0) 20 *
21 * According to ACPI 3.0, FADT.flags.RESET_REG_SUP indicates
22 * whether the ACPI reset mechanism is supported.
23 *
24 * However, some boxes have this bit clear, yet a valid
25 * ACPI_RESET_REG & RESET_VALUE, and ACPI reboot is the only
26 * mechanism that works for them after S3.
27 *
28 * This suggests that other operating systems may not be checking
29 * the RESET_REG_SUP bit, and are using other means to decide
30 * whether to use the ACPI reboot mechanism or not.
31 *
32 * So when acpi reboot is requested,
33 * only the reset_register is checked. If the following
34 * conditions are met, it indicates that the reset register is supported.
35 * a. reset_register is not zero
36 * b. the access width is eight
37 * c. the bit_offset is zero
38 */
39 if (!(rr->address) || rr->bit_width != 8 || rr->bit_offset != 0)
21 return; 40 return;
22 41
23 reset_value = acpi_gbl_FADT.reset_value; 42 reset_value = acpi_gbl_FADT.reset_value;