2 files changed, 18 insertions, 1 deletions

diff --git a/Documentation/devicetree/bindings/dma/ste-dma40.txt b/Documentation/devicetree/bindings/dma/ste-dma40.txt
index aa272d866f6e..bea5b73a7390 100644
--- a/Documentation/devicetree/bindings/dma/ste-dma40.txt
+++ b/Documentation/devicetree/bindings/dma/ste-dma40.txt
@@ -11,6 +11,7 @@ Required properties:
 Optional properties:
 - dma-channels: Number of channels supported by hardware - if not present
                 the driver will attempt to obtain the information from H/W
+- disabled-channels: Channels which can not be used
 
 Example:
 
@@ -23,6 +24,7 @@ Example:
 
                 #dma-cells = <2>;
                 memcpy-channels  = <56 57 58 59 60>;
+                disabled-channels  = <12>;
                 dma-channels = <8>;
         };
 
diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index 4e528dd30ad5..ffac8225ff54 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -3482,7 +3482,7 @@ static int __init d40_of_probe(struct platform_device *pdev,
                                struct device_node *np)
 {
         struct stedma40_platform_data *pdata;
-        int num_phy = 0, num_memcpy = 0;
+        int num_phy = 0, num_memcpy = 0, num_disabled = 0;
         const const __be32 *list;
 
         pdata = devm_kzalloc(&pdev->dev,
@@ -3511,6 +3511,21 @@ static int __init d40_of_probe(struct platform_device *pdev,
                                    dma40_memcpy_channels,
                                    num_memcpy);
 
+        list = of_get_property(np, "disabled-channels", &num_disabled);
+        num_disabled /= sizeof(*list);
+
+        if (num_disabled > STEDMA40_MAX_PHYS || num_disabled < 0) {
+                d40_err(&pdev->dev,
+                        "Invalid number of disabled channels specified (%d)\n",
+                        num_disabled);
+                return -EINVAL;
+        }
+
+        of_property_read_u32_array(np, "disabled-channels",
+                                   pdata->disabled_channels,
+                                   num_disabled);
+        pdata->disabled_channels[num_disabled] = -1;
+
         pdev->dev.platform_data = pdata;
 
         return 0;