[PATCH v11 1/7] ACPI: scan: Obtain device's desired enumeration power state

From: Sakari Ailus
Date: Wed Feb 10 2021 - 18:15:01 EST


Store a device's desired enumeration power state in struct
acpi_device_power during acpi_device object's initialisation.

Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
---
drivers/acpi/scan.c | 4 ++++
include/acpi/acpi_bus.h | 1 +
2 files changed, 5 insertions(+)

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index a184529d8fa40..6a9b4a92c4f66 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -987,6 +987,7 @@ static void acpi_bus_init_power_state(struct acpi_device *device, int state)

static void acpi_bus_get_power_flags(struct acpi_device *device)
{
+ unsigned long long dse = ACPI_STATE_D0;
u32 i;

/* Presence of _PS0|_PR0 indicates 'power manageable' */
@@ -1008,6 +1009,9 @@ static void acpi_bus_get_power_flags(struct acpi_device *device)
if (acpi_has_method(device->handle, "_DSW"))
device->power.flags.dsw_present = 1;

+ acpi_evaluate_integer(device->handle, "_DSE", NULL, &dse);
+ device->power.state_for_enumeration = dse;
+
/*
* Enumerate supported power management states
*/
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 02a716a0af5d4..becfc9f57002b 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -276,6 +276,7 @@ struct acpi_device_power {
int state; /* Current state */
struct acpi_device_power_flags flags;
struct acpi_device_power_state states[ACPI_D_STATE_COUNT]; /* Power states (D0-D3Cold) */
+ u8 state_for_enumeration; /* Maximum power state for enumeration */
};

/* Performance Management */
--
2.20.1