1 files changed, 144 insertions, 155 deletions

diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index 844c155aeb0f..9ac2a9fa90ff 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -56,9 +56,6 @@ ACPI_MODULE_NAME("power");
 #define ACPI_POWER_RESOURCE_STATE_ON    0x01
 #define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
 
-int acpi_power_nocheck;
-module_param_named(power_nocheck, acpi_power_nocheck, bool, 000);
-
 static int acpi_power_add(struct acpi_device *device);
 static int acpi_power_remove(struct acpi_device *device, int type);
 static int acpi_power_resume(struct acpi_device *device);
@@ -80,18 +77,13 @@ static struct acpi_driver acpi_power_driver = {
                 },
 };
 
-struct acpi_power_reference {
-        struct list_head node;
-        struct acpi_device *device;
-};
-
 struct acpi_power_resource {
         struct acpi_device * device;
         acpi_bus_id name;
         u32 system_level;
         u32 order;
+        unsigned int ref_count;
         struct mutex resource_lock;
-        struct list_head reference;
 };
 
 static struct list_head acpi_power_resource_list;
@@ -153,9 +145,8 @@ static int acpi_power_get_state(acpi_handle handle, int *state)
 
 static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state)
 {
-        int result = 0, state1;
-        u32 i = 0;
-
+        int cur_state;
+        int i = 0;
 
         if (!list || !state)
                 return -EINVAL;
@@ -163,122 +154,149 @@ static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state)
         /* The state of the list is 'on' IFF all resources are 'on'. */
 
         for (i = 0; i < list->count; i++) {
-                /*
-                 * The state of the power resource can be obtained by
-                 * using the ACPI handle. In such case it is unnecessary to
-                 * get the Power resource first and then get its state again.
-                 */
-                result = acpi_power_get_state(list->handles[i], &state1);
+                struct acpi_power_resource *resource;
+                acpi_handle handle = list->handles[i];
+                int result;
+
+                result = acpi_power_get_context(handle, &resource);
                 if (result)
                         return result;
 
-                *state = state1;
+                mutex_lock(&resource->resource_lock);
+
+                result = acpi_power_get_state(handle, &cur_state);
+
+                mutex_unlock(&resource->resource_lock);
 
-                if (*state != ACPI_POWER_RESOURCE_STATE_ON)
+                if (result)
+                        return result;
+
+                if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
                         break;
         }
 
         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
-                          *state ? "on" : "off"));
+                          cur_state ? "on" : "off"));
 
-        return result;
+        *state = cur_state;
+
+        return 0;
 }
 
-static int acpi_power_on(acpi_handle handle, struct acpi_device *dev)
+static int __acpi_power_on(struct acpi_power_resource *resource)
 {
-        int result = 0;
-        int found = 0;
         acpi_status status = AE_OK;
-        struct acpi_power_resource *resource = NULL;
-        struct list_head *node, *next;
-        struct acpi_power_reference *ref;
 
+        status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL);
+        if (ACPI_FAILURE(status))
+                return -ENODEV;
+
+        /* Update the power resource's _device_ power state */
+        resource->device->power.state = ACPI_STATE_D0;
+
+        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n",
+                          resource->name));
+
+        return 0;
+}
+
+static int acpi_power_on(acpi_handle handle)
+{
+        int result = 0;
+        struct acpi_power_resource *resource = NULL;
 
         result = acpi_power_get_context(handle, &resource);
         if (result)
                 return result;
 
         mutex_lock(&resource->resource_lock);
-        list_for_each_safe(node, next, &resource->reference) {
-                ref = container_of(node, struct acpi_power_reference, node);
-                if (dev->handle == ref->device->handle) {
-                        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already referenced by resource [%s]\n",
-                                  dev->pnp.bus_id, resource->name));
-                        found = 1;
-                        break;
-                }
-        }
 
-        if (!found) {
-                ref = kmalloc(sizeof (struct acpi_power_reference),
-                    irqs_disabled() ? GFP_ATOMIC : GFP_KERNEL);
-                if (!ref) {
-                        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "kmalloc() failed\n"));
-                        mutex_unlock(&resource->resource_lock);
-                        return -ENOMEM;
-                }
-                list_add_tail(&ref->node, &resource->reference);
-                ref->device = dev;
-                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] added to resource [%s] references\n",
-                          dev->pnp.bus_id, resource->name));
+        if (resource->ref_count++) {
+                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                                  "Power resource [%s] already on",
+                                  resource->name));
+        } else {
+                result = __acpi_power_on(resource);
+                if (result)
+                        resource->ref_count--;
         }
-        mutex_unlock(&resource->resource_lock);
 
-        status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL);
-        if (ACPI_FAILURE(status))
-                return -ENODEV;
-
-        /* Update the power resource's _device_ power state */
-        resource->device->power.state = ACPI_STATE_D0;
+        mutex_unlock(&resource->resource_lock);
 
-        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned on\n",
-                          resource->name));
-        return 0;
+        return result;
 }
 
-static int acpi_power_off_device(acpi_handle handle, struct acpi_device *dev)
+static int acpi_power_off(acpi_handle handle)
 {
         int result = 0;
         acpi_status status = AE_OK;
         struct acpi_power_resource *resource = NULL;
-        struct list_head *node, *next;
-        struct acpi_power_reference *ref;
 
         result = acpi_power_get_context(handle, &resource);
         if (result)
                 return result;
 
         mutex_lock(&resource->resource_lock);
-        list_for_each_safe(node, next, &resource->reference) {
-                ref = container_of(node, struct acpi_power_reference, node);
-                if (dev->handle == ref->device->handle) {
-                        list_del(&ref->node);
-                        kfree(ref);
-                        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] removed from resource [%s] references\n",
-                            dev->pnp.bus_id, resource->name));
-                        break;
-                }
+
+        if (!resource->ref_count) {
+                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                                  "Power resource [%s] already off",
+                                  resource->name));
+                goto unlock;
         }
 
-        if (!list_empty(&resource->reference)) {
-                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Cannot turn resource [%s] off - resource is in use\n",
-                    resource->name));
-                mutex_unlock(&resource->resource_lock);
-                return 0;
+        if (--resource->ref_count) {
+                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                                  "Power resource [%s] still in use\n",
+                                  resource->name));
+                goto unlock;
         }
-        mutex_unlock(&resource->resource_lock);
 
         status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL);
-        if (ACPI_FAILURE(status))
-                return -ENODEV;
+        if (ACPI_FAILURE(status)) {
+                result = -ENODEV;
+        } else {
+                /* Update the power resource's _device_ power state */
+                resource->device->power.state = ACPI_STATE_D3;
 
-        /* Update the power resource's _device_ power state */
-        resource->device->power.state = ACPI_STATE_D3;
+                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                                  "Power resource [%s] turned off\n",
+                                  resource->name));
+        }
 
-        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned off\n",
-                          resource->name));
+ unlock:
+        mutex_unlock(&resource->resource_lock);
 
-        return 0;
+        return result;
+}
+
+static void __acpi_power_off_list(struct acpi_handle_list *list, int num_res)
+{
+        int i;
+
+        for (i = num_res - 1; i >= 0 ; i--)
+                acpi_power_off(list->handles[i]);
+}
+
+static void acpi_power_off_list(struct acpi_handle_list *list)
+{
+        __acpi_power_off_list(list, list->count);
+}
+
+static int acpi_power_on_list(struct acpi_handle_list *list)
+{
+        int result = 0;
+        int i;
+
+        for (i = 0; i < list->count; i++) {
+                result = acpi_power_on(list->handles[i]);
+                if (result) {
+                        __acpi_power_off_list(list, i);
+                        break;
+                }
+        }
+
+        return result;
 }
 
 /**
@@ -364,7 +382,7 @@ int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
 
         /* Open power resource */
         for (i = 0; i < dev->wakeup.resources.count; i++) {
-                int ret = acpi_power_on(dev->wakeup.resources.handles[i], dev);
+                int ret = acpi_power_on(dev->wakeup.resources.handles[i]);
                 if (ret) {
                         printk(KERN_ERR PREFIX "Transition power state\n");
                         dev->wakeup.flags.valid = 0;
@@ -419,8 +437,7 @@ int acpi_disable_wakeup_device_power(struct acpi_device *dev)
 
         /* Close power resource */
         for (i = 0; i < dev->wakeup.resources.count; i++) {
-                int ret = acpi_power_off_device(
-                                dev->wakeup.resources.handles[i], dev);
+                int ret = acpi_power_off(dev->wakeup.resources.handles[i]);
                 if (ret) {
                         printk(KERN_ERR PREFIX "Transition power state\n");
                         dev->wakeup.flags.valid = 0;
@@ -438,19 +455,16 @@ int acpi_disable_wakeup_device_power(struct acpi_device *dev)
                              Device Power Management
    -------------------------------------------------------------------------- */
 
-int acpi_power_get_inferred_state(struct acpi_device *device)
+int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
 {
         int result = 0;
         struct acpi_handle_list *list = NULL;
         int list_state = 0;
         int i = 0;
 
-
-        if (!device)
+        if (!device || !state)
                 return -EINVAL;
 
-        device->power.state = ACPI_STATE_UNKNOWN;
-
         /*
          * We know a device's inferred power state when all the resources
          * required for a given D-state are 'on'.
@@ -465,66 +479,51 @@ int acpi_power_get_inferred_state(struct acpi_device *device)
                         return result;
 
                 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
-                        device->power.state = i;
+                        *state = i;
                         return 0;
                 }
         }
 
-        device->power.state = ACPI_STATE_D3;
-
+        *state = ACPI_STATE_D3;
         return 0;
 }
 
-int acpi_power_transition(struct acpi_device *device, int state)
+int acpi_power_on_resources(struct acpi_device *device, int state)
 {
-        int result = 0;
-        struct acpi_handle_list *cl = NULL;     /* Current Resources */
-        struct acpi_handle_list *tl = NULL;     /* Target Resources */
-        int i = 0;
+        if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3)
+                return -EINVAL;
+
+        return acpi_power_on_list(&device->power.states[state].resources);
+}
 
+int acpi_power_transition(struct acpi_device *device, int state)
+{
+        int result;
 
         if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
                 return -EINVAL;
 
+        if (device->power.state == state)
+                return 0;
+
         if ((device->power.state < ACPI_STATE_D0)
             || (device->power.state > ACPI_STATE_D3))
                 return -ENODEV;
 
-        cl = &device->power.states[device->power.state].resources;
-        tl = &device->power.states[state].resources;
-
         /* TBD: Resources must be ordered. */
 
         /*
          * First we reference all power resources required in the target list
-         * (e.g. so the device doesn't lose power while transitioning).
-         */
-        for (i = 0; i < tl->count; i++) {
-                result = acpi_power_on(tl->handles[i], device);
-                if (result)
-                        goto end;
-        }
-
-        if (device->power.state == state) {
-                goto end;
-        }
-
-        /*
-         * Then we dereference all power resources used in the current list.
+         * (e.g. so the device doesn't lose power while transitioning).  Then,
+         * we dereference all power resources used in the current list.
          */
-        for (i = 0; i < cl->count; i++) {
-                result = acpi_power_off_device(cl->handles[i], device);
-                if (result)
-                        goto end;
-        }
+        result = acpi_power_on_list(&device->power.states[state].resources);
+        if (!result)
+                acpi_power_off_list(
+                        &device->power.states[device->power.state].resources);
 
-     end:
-        if (result)
-                device->power.state = ACPI_STATE_UNKNOWN;
-        else {
-        /* We shouldn't change the state till all above operations succeed */
-                device->power.state = state;
-        }
+        /* We shouldn't change the state unless the above operations succeed. */
+        device->power.state = result ? ACPI_STATE_UNKNOWN : state;
 
         return result;
 }
@@ -551,7 +550,6 @@ static int acpi_power_add(struct acpi_device *device)
 
         resource->device = device;
         mutex_init(&resource->resource_lock);
-        INIT_LIST_HEAD(&resource->reference);
         strcpy(resource->name, device->pnp.bus_id);
         strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
         strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
@@ -594,22 +592,14 @@ static int acpi_power_add(struct acpi_device *device)
 
 static int acpi_power_remove(struct acpi_device *device, int type)
 {
-        struct acpi_power_resource *resource = NULL;
-        struct list_head *node, *next;
+        struct acpi_power_resource *resource;
 
-
-        if (!device || !acpi_driver_data(device))
+        if (!device)
                 return -EINVAL;
 
         resource = acpi_driver_data(device);
-
-        mutex_lock(&resource->resource_lock);
-        list_for_each_safe(node, next, &resource->reference) {
-                struct acpi_power_reference *ref = container_of(node, struct acpi_power_reference, node);
-                list_del(&ref->node);
-                kfree(ref);
-        }
-        mutex_unlock(&resource->resource_lock);
+        if (!resource)
+                return -EINVAL;
 
         kfree(resource);
 
@@ -619,29 +609,28 @@ static int acpi_power_remove(struct acpi_device *device, int type)
 static int acpi_power_resume(struct acpi_device *device)
 {
         int result = 0, state;
-        struct acpi_power_resource *resource = NULL;
-        struct acpi_power_reference *ref;
+        struct acpi_power_resource *resource;
 
-        if (!device || !acpi_driver_data(device))
+        if (!device)
                 return -EINVAL;
 
         resource = acpi_driver_data(device);
+        if (!resource)
+                return -EINVAL;
+
+        mutex_lock(&resource->resource_lock);
 
         result = acpi_power_get_state(device->handle, &state);
         if (result)
-                return result;
+                goto unlock;
 
-        mutex_lock(&resource->resource_lock);
-        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);
-                result = acpi_power_on(device->handle, ref->device);
-                return result;
-        }
+        if (state == ACPI_POWER_RESOURCE_STATE_OFF && resource->ref_count)
+                result = __acpi_power_on(resource);
 
+ unlock:
         mutex_unlock(&resource->resource_lock);
-        return 0;
+
+        return result;
 }
 
 int __init acpi_power_init(void)