Merge tag 'iio-fixes-for-3.16a' of git://git.kernel.org/pub/scm/linux/kernel/git...

[karo-tx-linux.git] / drivers / of / platform.c

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 92c060e58b02e2e1c12f427b03787465157f2913..6c48d73a7fd7c0f60d6a5a1d82c65b3045d1d3a5 100644 (file)
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -138,9 +138,6 @@ struct platform_device *of_device_alloc(struct device_node *np,
        }
 
        dev->dev.of_node = of_node_get(np);
-#if defined(CONFIG_MICROBLAZE)
-       dev->dev.dma_mask = &dev->archdata.dma_mask;
-#endif
        dev->dev.parent = parent;
 
        if (bus_id)
@@ -152,6 +149,64 @@ struct platform_device *of_device_alloc(struct device_node *np,
 }
 EXPORT_SYMBOL(of_device_alloc);
 
+/**
+ * of_dma_configure - Setup DMA configuration
+ * @dev:       Device to apply DMA configuration
+ *
+ * Try to get devices's DMA configuration from DT and update it
+ * accordingly.
+ *
+ * In case if platform code need to use own special DMA configuration,it
+ * can use Platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE event
+ * to fix up DMA configuration.
+ */
+static void of_dma_configure(struct platform_device *pdev)
+{
+       u64 dma_addr, paddr, size;
+       int ret;
+       struct device *dev = &pdev->dev;
+
+#if defined(CONFIG_MICROBLAZE)
+       pdev->archdata.dma_mask = 0xffffffffUL;
+#endif
+
+       /*
+        * Set default dma-mask to 32 bit. Drivers are expected to setup
+        * the correct supported dma_mask.
+        */
+       dev->coherent_dma_mask = DMA_BIT_MASK(32);
+
+       /*
+        * Set it to coherent_dma_mask by default if the architecture
+        * code has not set it.
+        */
+       if (!dev->dma_mask)
+               dev->dma_mask = &dev->coherent_dma_mask;
+
+       /*
+        * if dma-coherent property exist, call arch hook to setup
+        * dma coherent operations.
+        */
+       if (of_dma_is_coherent(dev->of_node)) {
+               set_arch_dma_coherent_ops(dev);
+               dev_dbg(dev, "device is dma coherent\n");
+       }
+
+       /*
+        * if dma-ranges property doesn't exist - just return else
+        * setup the dma offset
+        */
+       ret = of_dma_get_range(dev->of_node, &dma_addr, &paddr, &size);
+       if (ret < 0) {
+               dev_dbg(dev, "no dma range information to setup\n");
+               return;
+       }
+
+       /* DMA ranges found. Calculate and set dma_pfn_offset */
+       dev->dma_pfn_offset = PFN_DOWN(paddr - dma_addr);
+       dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", dev->dma_pfn_offset);
+}
+
 /**
  * of_platform_device_create_pdata - Alloc, initialize and register an of_device
  * @np: pointer to node to create device for
@@ -178,12 +233,7 @@ static struct platform_device *of_platform_device_create_pdata(
        if (!dev)
                goto err_clear_flag;
 
-#if defined(CONFIG_MICROBLAZE)
-       dev->archdata.dma_mask = 0xffffffffUL;
-#endif
-       dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
-       if (!dev->dev.dma_mask)
-               dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
+       of_dma_configure(dev);
        dev->dev.bus = &platform_bus_type;
        dev->dev.platform_data = platform_data;