drivers: uio_dmem_genirq: Don't use DMA_ERROR_CODE to indicate unmapped regions

DMA_ERROR_CODE is not defined on all architectures and is architecture
specific.  Instead, use the constant, ~0 to indicate unmapped regions.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Damian Hobson-Garcia <dhobsong@igel.co.jp>
Cc: "Hans J. Koch" <hjk@hansjkoch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 5 insertions, 3 deletions

diff --git a/Documentation/DocBook/uio-howto.tmpl b/Documentation/DocBook/uio-howto.tmpl
index fdbf86fcfccd..ddb05e98af0d 100644
--- a/Documentation/DocBook/uio-howto.tmpl
+++ b/Documentation/DocBook/uio-howto.tmpl
@@ -771,7 +771,7 @@ framework to set up sysfs files for this region. Simply leave it alone.
         <varname>/sys/class/uio/uioX/maps/mapY/*</varname>.
         The dynmaic memory regions will be freed when the UIO device file is
         closed. When no processes are holding the device file open, the address
-        returned to userspace is DMA_ERROR_CODE.
+        returned to userspace is ~0.
         </para>
 </sect1>
 
diff --git a/drivers/uio/uio_dmem_genirq.c b/drivers/uio/uio_dmem_genirq.c
index d8bbe0783cdc..7be8d0421cae 100644
--- a/drivers/uio/uio_dmem_genirq.c
+++ b/drivers/uio/uio_dmem_genirq.c
@@ -29,6 +29,7 @@
 #include <linux/of_address.h>
 
 #define DRIVER_NAME "uio_dmem_genirq"
+#define DMEM_MAP_ERROR (~0)
 
 struct uio_dmem_genirq_platdata {
         struct uio_info *uioinfo;
@@ -60,6 +61,7 @@ static int uio_dmem_genirq_open(struct uio_info *info, struct inode *inode)
                 addr = dma_alloc_coherent(&priv->pdev->dev, uiomem->size,
                                 (dma_addr_t *)&uiomem->addr, GFP_KERNEL);
                 if (!addr) {
+                        uiomem->addr = DMEM_MAP_ERROR;
                         ret = -ENOMEM;
                         break;
                 }
@@ -95,7 +97,7 @@ static int uio_dmem_genirq_release(struct uio_info *info, struct inode *inode)
                 dma_free_coherent(&priv->pdev->dev, uiomem->size,
                                 priv->dmem_region_vaddr[dmem_region++],
                                 uiomem->addr);
-                uiomem->addr = DMA_ERROR_CODE;
+                uiomem->addr = DMEM_MAP_ERROR;
                 ++uiomem;
         }
 
@@ -238,7 +240,7 @@ static int uio_dmem_genirq_probe(struct platform_device *pdev)
                         break;
                 }
                 uiomem->memtype = UIO_MEM_PHYS;
-                uiomem->addr = DMA_ERROR_CODE;
+                uiomem->addr = DMEM_MAP_ERROR;
                 uiomem->size = pdata->dynamic_region_sizes[i];
                 ++uiomem;
         }