+ chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ /* DMARS area is optional, if absent, this controller cannot do slave DMA */
+ dmars = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ /*
+ * IRQ resources:
+ * 1. there always must be at least one IRQ IO-resource. On SH4 it is
+ * the error IRQ, in which case it is the only IRQ in this resource:
+ * start == end. If it is the only IRQ resource, all channels also
+ * use the same IRQ.
+ * 2. DMA channel IRQ resources can be specified one per resource or in
+ * ranges (start != end)
+ * 3. iff all events (channels and, optionally, error) on this
+ * controller use the same IRQ, only one IRQ resource can be
+ * specified, otherwise there must be one IRQ per channel, even if
+ * some of them are equal
+ * 4. if all IRQs on this controller are equal or if some specific IRQs
+ * specify IORESOURCE_IRQ_SHAREABLE in their resources, they will be
+ * requested with the IRQF_SHARED flag
+ */
+ errirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (!chan || !errirq_res)
+ return -ENODEV;
+
+ if (!request_mem_region(chan->start, resource_size(chan), pdev->name)) {
+ dev_err(&pdev->dev, "DMAC register region already claimed\n");
+ return -EBUSY;
+ }
+
+ if (dmars && !request_mem_region(dmars->start, resource_size(dmars), pdev->name)) {
+ dev_err(&pdev->dev, "DMAC DMARS region already claimed\n");
+ err = -EBUSY;
+ goto ermrdmars;
+ }
+
+ err = -ENOMEM;