redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity

ACPI: suspend: restore BM_RLD on resume

Browse source 
In 2.6.29,
31878dd86b
"ACPI: remove BM_RLD access from idle entry path"
moved BM_RLD initialization to init-time from run time.

But we discovered that some BIOS do not restore BM_RLD
after suspend, causing device errors on C3 and C4
after resume.  So now the kernel restores BM_RLD.

http://bugzilla.kernel.org/show_bug.cgi?id=13032

Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Len Brown 2009-05-07 22:19:45 -04:00
parent 413f81eba3
commit 815ab0fd40
1 changed files with 23 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

23
drivers/acpi/processor_idle.c
View file

@ -202,15 +202,38 @@ static void acpi_state_timer_broadcast(struct acpi_processor *pr,
* Suspend / resume control
*/
static int acpi_idle_suspend;
static u32 saved_bm_rld;
static void acpi_idle_bm_rld_save(void)
{
acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &saved_bm_rld);
}
static void acpi_idle_bm_rld_restore(void)
{
u32 resumed_bm_rld;
acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &resumed_bm_rld);
if (resumed_bm_rld != saved_bm_rld)
acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld);
}
int acpi_processor_suspend(struct acpi_device * device, pm_message_t state)
{
if (acpi_idle_suspend == 1)
return 0;
acpi_idle_bm_rld_save();
acpi_idle_suspend = 1;
return 0;
}
int acpi_processor_resume(struct acpi_device * device)
{
if (acpi_idle_suspend == 0)
return 0;
acpi_idle_bm_rld_restore();
acpi_idle_suspend = 0;
return 0;
}