ACPI: power: don't cache power resource state

ACPI may change power resource state behind our back, so don't
keep our local copy, which may not be valid.

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index fb2cff9..fdee82d 100644 (file)
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -198,11 +198,9 @@ int acpi_bus_set_power(acpi_handle handle, int state)
                return -ENODEV;
        }
        /*
-        * Get device's current power state if it's unknown
-        * This means device power state isn't initialized or previous setting failed
+        * Get device's current power state
         */
-       if ((device->power.state == ACPI_STATE_UNKNOWN) || device->flags.force_power_state)
-               acpi_bus_get_power(device->handle, &device->power.state);
+       acpi_bus_get_power(device->handle, &device->power.state);
        if ((state == device->power.state) && !device->flags.force_power_state) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
                                  state));

diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index 57b9a29..af1769a 100644 (file)
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -86,7 +86,6 @@ struct acpi_power_resource {
        acpi_bus_id name;
        u32 system_level;
        u32 order;
-       int state;
        struct mutex resource_lock;
        struct list_head reference;
 };
@@ -128,33 +127,31 @@ acpi_power_get_context(acpi_handle handle,
        return 0;
 }
 
-static int acpi_power_get_state(struct acpi_power_resource *resource)
+static int acpi_power_get_state(struct acpi_power_resource *resource, int *state)
 {
        acpi_status status = AE_OK;
        unsigned long sta = 0;
 
 
-       if (!resource)
+       if (!resource || !state)
                return -EINVAL;
 
        status = acpi_evaluate_integer(resource->device->handle, "_STA", NULL, &sta);
        if (ACPI_FAILURE(status))
                return -ENODEV;
 
-       if (sta & 0x01)
-               resource->state = ACPI_POWER_RESOURCE_STATE_ON;
-       else
-               resource->state = ACPI_POWER_RESOURCE_STATE_OFF;
+       *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
+                             ACPI_POWER_RESOURCE_STATE_OFF;
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
-                         resource->name, resource->state ? "on" : "off"));
+                         resource->name, state ? "on" : "off"));
 
        return 0;
 }
 
 static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state)
 {
-       int result = 0;
+       int result = 0, state1;
        struct acpi_power_resource *resource = NULL;
        u32 i = 0;
 
@@ -168,11 +165,11 @@ static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state)
                result = acpi_power_get_context(list->handles[i], &resource);
                if (result)
                        return result;
-               result = acpi_power_get_state(resource);
+               result = acpi_power_get_state(resource, &state1);
                if (result)
                        return result;
 
-               *state = resource->state;
+               *state = state1;
 
                if (*state != ACPI_POWER_RESOURCE_STATE_ON)
                        break;
@@ -186,7 +183,7 @@ static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state)
 
 static int acpi_power_on(acpi_handle handle, struct acpi_device *dev)
 {
-       int result = 0;
+       int result = 0, state;
        int found = 0;
        acpi_status status = AE_OK;
        struct acpi_power_resource *resource = NULL;
@@ -224,20 +221,14 @@ static int acpi_power_on(acpi_handle handle, struct acpi_device *dev)
        }
        mutex_unlock(&resource->resource_lock);
 
-       if (resource->state == ACPI_POWER_RESOURCE_STATE_ON) {
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] already on\n",
-                                 resource->name));
-               return 0;
-       }
-
        status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL);
        if (ACPI_FAILURE(status))
                return -ENODEV;
 
-       result = acpi_power_get_state(resource);
+       result = acpi_power_get_state(resource, &state);
        if (result)
                return result;
-       if (resource->state != ACPI_POWER_RESOURCE_STATE_ON)
+       if (state != ACPI_POWER_RESOURCE_STATE_ON)
                return -ENOEXEC;
 
        /* Update the power resource's _device_ power state */
@@ -250,7 +241,7 @@ static int acpi_power_on(acpi_handle handle, struct acpi_device *dev)
 
 static int acpi_power_off_device(acpi_handle handle, struct acpi_device *dev)
 {
-       int result = 0;
+       int result = 0, state;
        acpi_status status = AE_OK;
        struct acpi_power_resource *resource = NULL;
        struct list_head *node, *next;
@@ -281,20 +272,14 @@ static int acpi_power_off_device(acpi_handle handle, struct acpi_device *dev)
        }
        mutex_unlock(&resource->resource_lock);
 
-       if (resource->state == ACPI_POWER_RESOURCE_STATE_OFF) {
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] already off\n",
-                                 resource->name));
-               return 0;
-       }
-
        status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL);
        if (ACPI_FAILURE(status))
                return -ENODEV;
 
-       result = acpi_power_get_state(resource);
+       result = acpi_power_get_state(resource, &state);
        if (result)
                return result;
-       if (resource->state != ACPI_POWER_RESOURCE_STATE_OFF)
+       if (state != ACPI_POWER_RESOURCE_STATE_OFF)
                return -ENOEXEC;
 
        /* Update the power resource's _device_ power state */
@@ -494,7 +479,7 @@ static struct proc_dir_entry *acpi_power_dir;
 static int acpi_power_seq_show(struct seq_file *seq, void *offset)
 {
        int count = 0;
-       int result = 0;
+       int result = 0, state;
        struct acpi_power_resource *resource = NULL;
        struct list_head *node, *next;
        struct acpi_power_reference *ref;
@@ -505,12 +490,12 @@ static int acpi_power_seq_show(struct seq_file *seq, void *offset)
        if (!resource)
                goto end;
 
-       result = acpi_power_get_state(resource);
+       result = acpi_power_get_state(resource, &state);
        if (result)
                goto end;
 
        seq_puts(seq, "state:                   ");
-       switch (resource->state) {
+       switch (state) {
        case ACPI_POWER_RESOURCE_STATE_ON:
                seq_puts(seq, "on\n");
                break;
@@ -591,7 +576,7 @@ static int acpi_power_remove_fs(struct acpi_device *device)
 
 static int acpi_power_add(struct acpi_device *device)
 {
-       int result = 0;
+       int result = 0, state;
        acpi_status status = AE_OK;
        struct acpi_power_resource *resource = NULL;
        union acpi_object acpi_object;
@@ -622,11 +607,11 @@ static int acpi_power_add(struct acpi_device *device)
        resource->system_level = acpi_object.power_resource.system_level;
        resource->order = acpi_object.power_resource.resource_order;
 
-       result = acpi_power_get_state(resource);
+       result = acpi_power_get_state(resource, &state);
        if (result)
                goto end;
 
-       switch (resource->state) {
+       switch (state) {
        case ACPI_POWER_RESOURCE_STATE_ON:
                device->power.state = ACPI_STATE_D0;
                break;
@@ -643,7 +628,7 @@ static int acpi_power_add(struct acpi_device *device)
                goto end;
 
        printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
-              acpi_device_bid(device), resource->state ? "on" : "off");
+              acpi_device_bid(device), state ? "on" : "off");
 
       end:
        if (result)
@@ -680,7 +665,7 @@ static int acpi_power_remove(struct acpi_device *device, int type)
 
 static int acpi_power_resume(struct acpi_device *device)
 {
-       int result = 0;
+       int result = 0, state;
        struct acpi_power_resource *resource = NULL;
        struct acpi_power_reference *ref;
 
@@ -689,12 +674,12 @@ static int acpi_power_resume(struct acpi_device *device)
 
        resource = (struct acpi_power_resource *)acpi_driver_data(device);
 
-       result = acpi_power_get_state(resource);
+       result = acpi_power_get_state(resource, &state);
        if (result)
                return result;
 
        mutex_lock(&resource->resource_lock);
-       if ((resource->state == ACPI_POWER_RESOURCE_STATE_OFF) &&
+       if (state == ACPI_POWER_RESOURCE_STATE_OFF &&
            !list_empty(&resource->reference)) {
                ref = container_of(resource->reference.next, struct acpi_power_reference, node);
                mutex_unlock(&resource->resource_lock);