PCI: pciehp: create files only for existing capabilities

Current pciehp driver creates 'attention' and 'latch' files even if
the controller doesn't support them. In this case, the contents of
those files are meaningless and unpredictable. Those files should be
created only if the controller has the corresponding capabilities.
Signed-off-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/hotplug/pciehp_core.c

@@ -72,18 +72,6 @@ static int get_adapter_status	(struct hotplug_slot *slot, u8 *value);
 static int get_max_bus_speed	(struct hotplug_slot *slot, enum pci_bus_speed *value);
 static int get_cur_bus_speed	(struct hotplug_slot *slot, enum pci_bus_speed *value);
 
-static struct hotplug_slot_ops pciehp_hotplug_slot_ops = {
-	.set_attention_status =	set_attention_status,
-	.enable_slot =		enable_slot,
-	.disable_slot =		disable_slot,
-	.get_power_status =	get_power_status,
-	.get_attention_status =	get_attention_status,
-	.get_latch_status =	get_latch_status,
-	.get_adapter_status =	get_adapter_status,
-  	.get_max_bus_speed =	get_max_bus_speed,
-  	.get_cur_bus_speed =	get_cur_bus_speed,
-};
-
 /**
  * release_slot - free up the memory used by a slot
  * @hotplug_slot: slot to free
@@ -95,6 +83,7 @@ static void release_slot(struct hotplug_slot *hotplug_slot)
 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 		 __func__, hotplug_slot_name(hotplug_slot));
 
+	kfree(hotplug_slot->ops);
 	kfree(hotplug_slot->info);
 	kfree(hotplug_slot);
 }
@@ -104,6 +93,7 @@ static int init_slot(struct controller *ctrl)
 	struct slot *slot = ctrl->slot;
 	struct hotplug_slot *hotplug = NULL;
 	struct hotplug_slot_info *info = NULL;
+	struct hotplug_slot_ops *ops = NULL;
 	char name[SLOT_NAME_SIZE];
 	int retval = -ENOMEM;
 
@@ -115,11 +105,28 @@ static int init_slot(struct controller *ctrl)
 	if (!info)
 		goto out;
 
+	/* Setup hotplug slot ops */
+	ops = kzalloc(sizeof(*ops), GFP_KERNEL);
+	if (!ops)
+		goto out;
+	ops->enable_slot = enable_slot;
+	ops->disable_slot = disable_slot;
+	ops->get_power_status = get_power_status;
+	ops->get_adapter_status = get_adapter_status;
+	ops->get_max_bus_speed = get_max_bus_speed;
+	ops->get_cur_bus_speed = get_cur_bus_speed;
+	if (MRL_SENS(ctrl))
+		ops->get_latch_status = get_latch_status;
+	if (ATTN_LED(ctrl)) {
+		ops->get_attention_status = get_attention_status;
+		ops->set_attention_status = set_attention_status;
+	}
+
 	/* register this slot with the hotplug pci core */
 	hotplug->info = info;
 	hotplug->private = slot;
 	hotplug->release = &release_slot;
-	hotplug->ops = &pciehp_hotplug_slot_ops;
+	hotplug->ops = ops;
 	slot->hotplug_slot = hotplug;
 	snprintf(name, SLOT_NAME_SIZE, "%u", PSN(ctrl));
 
@@ -139,6 +146,7 @@ static int init_slot(struct controller *ctrl)
 	get_adapter_status(hotplug, &info->adapter_status);
 out:
 	if (retval) {
+		kfree(ops);
 		kfree(info);
 		kfree(hotplug);
 	}
@@ -161,9 +169,7 @@ static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
 		  __func__, slot_name(slot));
 
 	hotplug_slot->info->attention_status = status;
-
-	if (ATTN_LED(slot->ctrl))
-		pciehp_set_attention_status(slot, status);
+	pciehp_set_attention_status(slot, status);
 
 	return 0;
 }