platform/x86/intel/vsec: Enhance and Export intel_vsec_add_aux()

Remove static for intel_vsec_add_aux() and export this interface so that
it can be used by other vsec related modules.

This driver creates aux devices by parsing PCI-VSEC, which allows
individual drivers to load on those devices. Those driver may further
create more devices on aux bus by parsing the PCI MMIO region.

For example, TPMI (Topology Aware Register and PM Capsule Interface)
creates device nodes for power management features by parsing MMIO region.

When TPMI driver creates devices, it can reuse existing function
intel_vsec_add_aux() to create aux devices with TPMI device as the parent.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: David E. Box <david.e.box@linux.intel.com>
Link: https://lore.kernel.org/r/20230202010738.2186174-3-srinivas.pandruvada@linux.intel.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

drivers/platform/x86/intel/vsec.c

@@ -138,8 +138,9 @@ static void intel_vsec_dev_release(struct device *dev)
 	kfree(intel_vsec_dev);
 }
 
-static int intel_vsec_add_aux(struct pci_dev *pdev, struct intel_vsec_device *intel_vsec_dev,
-			      const char *name)
+int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent,
+		       struct intel_vsec_device *intel_vsec_dev,
+		       const char *name)
 {
 	struct auxiliary_device *auxdev = &intel_vsec_dev->auxdev;
 	int ret, id;
@@ -150,9 +151,12 @@ static int intel_vsec_add_aux(struct pci_dev *pdev, struct intel_vsec_device *in
 		return ret;
 	}
 
+	if (!parent)
+		parent = &pdev->dev;
+
 	auxdev->id = ret;
 	auxdev->name = name;
-	auxdev->dev.parent = &pdev->dev;
+	auxdev->dev.parent = parent;
 	auxdev->dev.release = intel_vsec_dev_release;
 
 	ret = auxiliary_device_init(auxdev);
@@ -169,7 +173,7 @@ static int intel_vsec_add_aux(struct pci_dev *pdev, struct intel_vsec_device *in
 		return ret;
 	}
 
-	ret = devm_add_action_or_reset(&pdev->dev, intel_vsec_remove_aux,
+	ret = devm_add_action_or_reset(parent, intel_vsec_remove_aux,
 				       auxdev);
 	if (ret < 0)
 		return ret;
@@ -182,6 +186,7 @@ static int intel_vsec_add_aux(struct pci_dev *pdev, struct intel_vsec_device *in
 
 	return 0;
 }
+EXPORT_SYMBOL_NS_GPL(intel_vsec_add_aux, INTEL_VSEC);
 
 static int intel_vsec_add_dev(struct pci_dev *pdev, struct intel_vsec_header *header,
 			      struct intel_vsec_platform_info *info)
@@ -239,7 +244,8 @@ static int intel_vsec_add_dev(struct pci_dev *pdev, struct intel_vsec_header *he
 	else
 		intel_vsec_dev->ida = &intel_vsec_ida;
 
-	return intel_vsec_add_aux(pdev, intel_vsec_dev, intel_vsec_name(header->id));
+	return intel_vsec_add_aux(pdev, NULL, intel_vsec_dev,
+				  intel_vsec_name(header->id));
 }
 
 static bool intel_vsec_walk_header(struct pci_dev *pdev,

drivers/platform/x86/intel/vsec.h

@@ -40,6 +40,10 @@ struct intel_vsec_device {
 	int num_resources;
 };
 
+int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent,
+		       struct intel_vsec_device *intel_vsec_dev,
+		       const char *name);
+
 static inline struct intel_vsec_device *dev_to_ivdev(struct device *dev)
 {
 	return container_of(dev, struct intel_vsec_device, auxdev.dev);