ACPI: Fix D3hot v D3cold confusion

Before this patch, ACPI_STATE_D3 incorrectly referenced D3hot
in some places, but D3cold in other places.

After this patch, ACPI_STATE_D3 always means ACPI_STATE_D3_COLD;
and all references to D3hot use ACPI_STATE_D3_HOT.

ACPI's _PR3 method is used to enter both D3hot and D3cold states.
What distinguishes D3hot from D3cold is the presence _PR3
(Power Resources for D3hot)  If these resources are all ON,
then the state is D3hot.  If _PR3 is not present,
or all _PR0 resources for the devices are OFF,
then the state is D3cold.

This patch applies after Linux-3.4-rc1.
A future syntax cleanup may remove ACPI_STATE_D3
to emphasize that it always means ACPI_STATE_D3_COLD.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Aaron Lu <aaron.lu@amd.com>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index 7049a7d..330bb4d 100644 (file)
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -631,7 +631,7 @@ int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
         * We know a device's inferred power state when all the resources
         * required for a given D-state are 'on'.
         */
-       for (i = ACPI_STATE_D0; i < ACPI_STATE_D3; i++) {
+       for (i = ACPI_STATE_D0; i < ACPI_STATE_D3_HOT; i++) {
                list = &device->power.states[i].resources;
                if (list->count < 1)
                        continue;

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 767e2dc..7417267 100644 (file)
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -869,7 +869,7 @@ static int acpi_bus_get_power_flags(struct acpi_device *device)
        /*
         * Enumerate supported power management states
         */
-       for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
+       for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
                struct acpi_device_power_state *ps = &device->power.states[i];
                char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 
@@ -884,21 +884,18 @@ static int acpi_bus_get_power_flags(struct acpi_device *device)
                                acpi_bus_add_power_resource(ps->resources.handles[j]);
                }
 
-               /* The exist of _PR3 indicates D3Cold support */
-               if (i == ACPI_STATE_D3) {
-                       status = acpi_get_handle(device->handle, object_name, &handle);
-                       if (ACPI_SUCCESS(status))
-                               device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
-               }
-
                /* Evaluate "_PSx" to see if we can do explicit sets */
                object_name[2] = 'S';
                status = acpi_get_handle(device->handle, object_name, &handle);
                if (ACPI_SUCCESS(status))
                        ps->flags.explicit_set = 1;
 
-               /* State is valid if we have some power control */
-               if (ps->resources.count || ps->flags.explicit_set)
+               /*
+                * State is valid if there are means to put the device into it.
+                * D3hot is only valid if _PR3 present.
+                */
+               if (ps->resources.count ||
+                   (ps->flags.explicit_set && i < ACPI_STATE_D3_HOT))
                        ps->flags.valid = 1;
 
                ps->power = -1; /* Unknown - driver assigned */

diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 0f150f2..1929c0c 100644 (file)
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -200,7 +200,7 @@ static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
                return PCI_D1;
        case ACPI_STATE_D2:
                return PCI_D2;
-       case ACPI_STATE_D3:
+       case ACPI_STATE_D3_HOT:
                return PCI_D3hot;
        case ACPI_STATE_D3_COLD:
                return PCI_D3cold;
@@ -223,7 +223,7 @@ static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
                [PCI_D0] = ACPI_STATE_D0,
                [PCI_D1] = ACPI_STATE_D1,
                [PCI_D2] = ACPI_STATE_D2,
-               [PCI_D3hot] = ACPI_STATE_D3,
+               [PCI_D3hot] = ACPI_STATE_D3_HOT,
                [PCI_D3cold] = ACPI_STATE_D3
        };
        int error = -EINVAL;

diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h
index eba6604..e8bcc47 100644 (file)
--- a/include/acpi/actypes.h
+++ b/include/acpi/actypes.h
@@ -499,9 +499,10 @@ typedef u64 acpi_integer;
 #define ACPI_STATE_D0                   (u8) 0
 #define ACPI_STATE_D1                   (u8) 1
 #define ACPI_STATE_D2                   (u8) 2
-#define ACPI_STATE_D3                   (u8) 3
-#define ACPI_STATE_D3_COLD              (u8) 4
-#define ACPI_D_STATES_MAX               ACPI_STATE_D3_COLD
+#define ACPI_STATE_D3_HOT               (u8) 3
+#define ACPI_STATE_D3                   (u8) 4
+#define ACPI_STATE_D3_COLD              ACPI_STATE_D3
+#define ACPI_D_STATES_MAX               ACPI_STATE_D3
 #define ACPI_D_STATE_COUNT              5
 
 #define ACPI_STATE_C0                   (u8) 0