iommu/of: mark an unused function as __maybe_unused

When CONFIG_OF_ADDRESS is not set, there is a build warning/error
about an unused function.
Annotate the function to quieten the warning/error.

../drivers/iommu/of_iommu.c:176:29: warning: 'iommu_resv_region_get_type' defined but not used [-Wunused-function]
  176 | static enum iommu_resv_type iommu_resv_region_get_type(struct device *dev, struct resource *phys,
      |                             ^~~~~~~~~~~~~~~~~~~~~~~~~~

Fixes: a5bf3cfce8cb ("iommu: Implement of_iommu_get_resv_regions()")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Will Deacon <will@kernel.org>
Cc: iommu@lists.linux.dev
Reviewed-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20230209010359.23831-1-rdunlap@infradead.org
[joro: Improve code formatting]
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index 3c2e2a13cf9cd07c758c0e9e101304e4f43595dd..40f57d293a79d45647650560122cc2b993907abc 100644 (file)
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -173,8 +173,10 @@ const struct iommu_ops *of_iommu_configure(struct device *dev,
        return ops;
 }
 
-static enum iommu_resv_type iommu_resv_region_get_type(struct device *dev, struct resource *phys,
-                                                      phys_addr_t start, size_t length)
+static enum iommu_resv_type __maybe_unused
+iommu_resv_region_get_type(struct device *dev,
+                          struct resource *phys,
+                          phys_addr_t start, size_t length)
 {
        phys_addr_t end = start + length - 1;