[PATCH v2 4/8] ACPI: PM: s2idle: Add acpi.sleep_no_lps0 module parameter

Rafael J. Wysocki
2019-07-30T10:05:51Z

Add a module parameter to prevent the ACPI LPS0 _DSM functions
from being invoked (if need be) and rework the suspend-to-idle
blacklist entries in acpisleep_dmi_table[] to make them simply
prevent suspend-to-idle from being used by default on the systems
in question (which really is the original purpose of those entries).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---

-> v2: Patch reworked, new subject.

---
drivers/acpi/sleep.c | 29 ++++++++++++++---------------
1 file changed, 14 insertions(+), 15 deletions(-)

Index: linux-pm/drivers/acpi/sleep.c
===================================================================
--- linux-pm.orig/drivers/acpi/sleep.c
+++ linux-pm/drivers/acpi/sleep.c
@@ -89,6 +89,10 @@ bool acpi_sleep_state_supported(u8 sleep
}

#ifdef CONFIG_ACPI_SLEEP
+static bool sleep_no_lps0 __read_mostly;
+module_param(sleep_no_lps0, bool, 0644);
+MODULE_PARM_DESC(sleep_no_lps0, "Do not use the special LPS0 device interface");
+
static u32 acpi_target_sleep_state = ACPI_STATE_S0;

u32 acpi_target_system_state(void)
@@ -158,11 +162,11 @@ static int __init init_nvs_nosave(const
return 0;
}

-static bool acpi_sleep_no_lps0;
+static bool acpi_sleep_default_s3;

-static int __init init_no_lps0(const struct dmi_system_id *d)
+static int __init init_default_s3(const struct dmi_system_id *d)
{
- acpi_sleep_no_lps0 = true;
+ acpi_sleep_default_s3 = true;
return 0;
}

@@ -363,7 +367,7 @@ static const struct dmi_system_id acpisl
* S0 Idle firmware interface.
*/
{
- .callback = init_no_lps0,
+ .callback = init_default_s3,
.ident = "Dell XPS13 9360",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
@@ -376,7 +380,7 @@ static const struct dmi_system_id acpisl
* https://bugzilla.kernel.org/show_bug.cgi?id=199057).
*/
{
- .callback = init_no_lps0,
+ .callback = init_default_s3,
.ident = "ThinkPad X1 Tablet(2016)",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
@@ -524,8 +528,9 @@ static void acpi_pm_end(void)
acpi_sleep_tts_switch(acpi_target_sleep_state);
}
#else /* !CONFIG_ACPI_SLEEP */
+#define sleep_no_lps0 (1)
#define acpi_target_sleep_state ACPI_STATE_S0
-#define acpi_sleep_no_lps0 (false)
+#define acpi_sleep_default_s3 (1)
static inline void acpi_sleep_dmi_check(void) {}
#endif /* CONFIG_ACPI_SLEEP */

@@ -904,12 +909,6 @@ static int lps0_device_attach(struct acp
if (lps0_device_handle)
return 0;

- if (acpi_sleep_no_lps0) {
- acpi_handle_info(adev->handle,
- "Low Power S0 Idle interface disabled\n");
- return 0;
- }
-
if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
return 0;

@@ -937,7 +936,7 @@ static int lps0_device_attach(struct acp
* Use suspend-to-idle by default if the default suspend mode was not
* set from the command line.
*/
- if (mem_sleep_default > PM_SUSPEND_MEM)
+ if (mem_sleep_default > PM_SUSPEND_MEM && !acpi_sleep_default_s3)
mem_sleep_current = PM_SUSPEND_TO_IDLE;

return 0;
@@ -972,7 +971,7 @@ static int acpi_s2idle_prepare(void)

static int acpi_s2idle_prepare_late(void)
{
- if (!lps0_device_handle)
+ if (!lps0_device_handle || sleep_no_lps0)
return 0;

if (pm_debug_messages_on)
@@ -1022,7 +1021,7 @@ static void acpi_s2idle_wake(void)

static void acpi_s2idle_restore_early(void)
{
- if (!lps0_device_handle)
+ if (!lps0_device_handle || sleep_no_lps0)
return;

acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT);