agp: tidy up handling of scratch pages w.r.t. DMA API

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 13 insertions, 10 deletions

diff --git a/drivers/char/agp/backend.c b/drivers/char/agp/backend.c
index 19ac3663acdc..3c3a487f7b9d 100644
--- a/drivers/char/agp/backend.c
+++ b/drivers/char/agp/backend.c
@@ -150,17 +150,20 @@ static int agp_backend_initialize(struct agp_bridge_data *bridge)
                 }
 
                 bridge->scratch_page_real = phys_to_gart(page_to_phys(page));
-                bridge->scratch_page = bridge->driver->mask_memory(bridge,
-                                           phys_to_gart(page_to_phys(page)), 0);
-
-                if (bridge->driver->agp_map_page &&
-                    bridge->driver->agp_map_page(phys_to_virt(page_to_phys(page)),
-                                                &bridge->scratch_page_dma)) {
-                        dev_err(&bridge->dev->dev,
-                                "unable to dma-map scratch page\n");
-                        rc = -ENOMEM;
-                        goto err_out_nounmap;
+                if (bridge->driver->agp_map_page) {
+                        if (bridge->driver->agp_map_page(phys_to_virt(page_to_phys(page)),
+                                                         &bridge->scratch_page_dma)) {
+                                dev_err(&bridge->dev->dev,
+                                        "unable to dma-map scratch page\n");
+                                rc = -ENOMEM;
+                                goto err_out_nounmap;
+                        }
+                } else {
+                        bridge->scratch_page_dma = phys_to_gart(page_to_phys(page));
                 }
+
+                bridge->scratch_page = bridge->driver->mask_memory(bridge,
+                                                   bridge->scratch_page_dma, 0);
         }
 
         size_value = bridge->driver->fetch_size();