dma-mapping: add dma_{map,unmap}_resource

Map/Unmap a device MMIO resource from a physical address. If no dma_map_ops
method is available the operation is a no-op.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 36 insertions, 0 deletions

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 673b7be85f7a..6e00c7fdbbd3 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -264,6 +264,42 @@ static inline void dma_unmap_page(struct device *dev, dma_addr_t addr,
         debug_dma_unmap_page(dev, addr, size, dir, false);
 }
 
+static inline dma_addr_t dma_map_resource(struct device *dev,
+                                          phys_addr_t phys_addr,
+                                          size_t size,
+                                          enum dma_data_direction dir,
+                                          unsigned long attrs)
+{
+        struct dma_map_ops *ops = get_dma_ops(dev);
+        unsigned long pfn = __phys_to_pfn(phys_addr);
+        dma_addr_t addr;
+
+        BUG_ON(!valid_dma_direction(dir));
+
+        /* Don't allow RAM to be mapped */
+        BUG_ON(pfn_valid(pfn));
+
+        addr = phys_addr;
+        if (ops->map_resource)
+                addr = ops->map_resource(dev, phys_addr, size, dir, attrs);
+
+        debug_dma_map_resource(dev, phys_addr, size, dir, addr);
+
+        return addr;
+}
+
+static inline void dma_unmap_resource(struct device *dev, dma_addr_t addr,
+                                      size_t size, enum dma_data_direction dir,
+                                      unsigned long attrs)
+{
+        struct dma_map_ops *ops = get_dma_ops(dev);
+
+        BUG_ON(!valid_dma_direction(dir));
+        if (ops->unmap_resource)
+                ops->unmap_resource(dev, addr, size, dir, attrs);
+        debug_dma_unmap_resource(dev, addr, size, dir);
+}
+
 static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
                                            size_t size,
                                            enum dma_data_direction dir)