iommu/ipmmu-vmsa: Use helper functions to access dev->iommu_fwspec

Use the new helpers dev_iommu_fwspec_get()/set() to access
the dev->iommu_fwspec pointer. This makes it easier to move
that pointer later into another struct.
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/ipmmu-vmsa.c

@@ -82,7 +82,9 @@ static struct ipmmu_vmsa_domain *to_vmsa_domain(struct iommu_domain *dom)
 
 static struct ipmmu_vmsa_device *to_ipmmu(struct device *dev)
 {
-	return dev->iommu_fwspec ? dev->iommu_fwspec->iommu_priv : NULL;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+
+	return fwspec ? fwspec->iommu_priv : NULL;
 }
 
 #define TLB_LOOP_TIMEOUT		100	/* 100us */
@@ -641,7 +643,7 @@ static void ipmmu_domain_free(struct iommu_domain *io_domain)
 static int ipmmu_attach_device(struct iommu_domain *io_domain,
 			       struct device *dev)
 {
-	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 	struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
 	struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
 	unsigned int i;
@@ -690,7 +692,7 @@ static int ipmmu_attach_device(struct iommu_domain *io_domain,
 static void ipmmu_detach_device(struct iommu_domain *io_domain,
 				struct device *dev)
 {
-	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 	struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
 	unsigned int i;
 
@@ -742,13 +744,15 @@ static phys_addr_t ipmmu_iova_to_phys(struct iommu_domain *io_domain,
 static int ipmmu_init_platform_device(struct device *dev,
 				      struct of_phandle_args *args)
 {
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 	struct platform_device *ipmmu_pdev;
 
 	ipmmu_pdev = of_find_device_by_node(args->np);
 	if (!ipmmu_pdev)
 		return -ENODEV;
 
-	dev->iommu_fwspec->iommu_priv = platform_get_drvdata(ipmmu_pdev);
+	fwspec->iommu_priv = platform_get_drvdata(ipmmu_pdev);
+
 	return 0;
 }