drivers: uio_dmem_genirq: Don't use DMA_ERROR_CODE to indicate unmapped regions
Damian Hobson-Garcia [Fri, 16 Nov 2012 05:46:10 +0000 (14:46 +0900)]
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>

Documentation/DocBook/uio-howto.tmpl
drivers/uio/uio_dmem_genirq.c

index fdbf86f..ddb05e9 100644 (file)
@@ -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>
 
index d8bbe07..7be8d04 100644 (file)
@@ -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;
        }