ACPI: Unconditionally set SCI_EN on resume
The ACPI spec tells us that the firmware will reenable SCI_EN on resume.
Reality disagrees in some cases. The ACPI spec tells us that the only way
to set SCI_EN is via an SMM call.
https://bugzilla.kernel.org/show_bug.cgi?id=13745 shows us that doing so
may break machines. Tracing the ACPI calls made by Windows shows that it
unconditionally sets SCI_EN on resume with a direct register write, and
therefore the overwhelming probability is that everything is fine with
this behaviour.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Tested-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index baa76bb..4ab2275 100644
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -80,22 +80,6 @@
#ifdef CONFIG_ACPI_SLEEP
static u32 acpi_target_sleep_state = ACPI_STATE_S0;
-/*
- * According to the ACPI specification the BIOS should make sure that ACPI is
- * enabled and SCI_EN bit is set on wake-up from S1 - S3 sleep states. Still,
- * some BIOSes don't do that and therefore we use acpi_enable() to enable ACPI
- * on such systems during resume. Unfortunately that doesn't help in
- * particularly pathological cases in which SCI_EN has to be set directly on
- * resume, although the specification states very clearly that this flag is
- * owned by the hardware. The set_sci_en_on_resume variable will be set in such
- * cases.
- */
-static bool set_sci_en_on_resume;
-
-void __init acpi_set_sci_en_on_resume(void)
-{
- set_sci_en_on_resume = true;
-}
/*
* ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
@@ -253,11 +237,8 @@
break;
}
- /* If ACPI is not enabled by the BIOS, we need to enable it here. */
- if (set_sci_en_on_resume)
- acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
- else
- acpi_enable();
+ /* This violates the spec but is required for bug compatibility. */
+ acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
/* Reprogram control registers and execute _BFS */
acpi_leave_sleep_state_prep(acpi_state);
@@ -346,12 +327,6 @@
return 0;
}
-static int __init init_set_sci_en_on_resume(const struct dmi_system_id *d)
-{
- set_sci_en_on_resume = true;
- return 0;
-}
-
static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
{
.callback = init_old_suspend_ordering,
@@ -370,22 +345,6 @@
},
},
{
- .callback = init_set_sci_en_on_resume,
- .ident = "Apple MacBook 1,1",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."),
- DMI_MATCH(DMI_PRODUCT_NAME, "MacBook1,1"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Apple MacMini 1,1",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."),
- DMI_MATCH(DMI_PRODUCT_NAME, "Macmini1,1"),
- },
- },
- {
.callback = init_old_suspend_ordering,
.ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
.matches = {
@@ -394,94 +353,6 @@
},
},
{
- .callback = init_set_sci_en_on_resume,
- .ident = "Toshiba Satellite L300",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
- DMI_MATCH(DMI_PRODUCT_NAME, "Satellite L300"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Hewlett-Packard HP G7000 Notebook PC",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
- DMI_MATCH(DMI_PRODUCT_NAME, "HP G7000 Notebook PC"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Hewlett-Packard HP Pavilion dv3 Notebook PC",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
- DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dv3 Notebook PC"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Hewlett-Packard Pavilion dv4",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
- DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dv4"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Hewlett-Packard Pavilion dv7",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
- DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dv7"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Hewlett-Packard Compaq Presario C700 Notebook PC",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
- DMI_MATCH(DMI_PRODUCT_NAME, "Compaq Presario C700 Notebook PC"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Hewlett-Packard Compaq Presario CQ40 Notebook PC",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
- DMI_MATCH(DMI_PRODUCT_NAME, "Compaq Presario CQ40 Notebook PC"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Lenovo ThinkPad T410",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
- DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T410"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Lenovo ThinkPad T510",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
- DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T510"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Lenovo ThinkPad W510",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
- DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad W510"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Lenovo ThinkPad X201[s]",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
- DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201"),
- },
- },
- {
.callback = init_old_suspend_ordering,
.ident = "Panasonic CF51-2L",
.matches = {
@@ -490,30 +361,6 @@
DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
},
},
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Dell Studio 1558",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
- DMI_MATCH(DMI_PRODUCT_NAME, "Studio 1558"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Dell Studio 1557",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
- DMI_MATCH(DMI_PRODUCT_NAME, "Studio 1557"),
- },
- },
- {
- .callback = init_set_sci_en_on_resume,
- .ident = "Dell Studio 1555",
- .matches = {
- DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
- DMI_MATCH(DMI_PRODUCT_NAME, "Studio 1555"),
- },
- },
{},
};
#endif /* CONFIG_SUSPEND */