+/*
+ * Allows changing the DMA callback function or data. This may be needed if
+ * the driver shares a single DMA channel for multiple dma triggers.
+ */
+int omap_set_dma_callback(int lch,
+ void (* callback)(int lch, u16 ch_status, void *data),
+ void *data)
+{
+ unsigned long flags;
+
+ if (lch < 0)
+ return -ENODEV;
+
+ spin_lock_irqsave(&dma_chan_lock, flags);
+ if (dma_chan[lch].dev_id == -1) {
+ printk(KERN_ERR "DMA callback for not set for free channel\n");
+ spin_unlock_irqrestore(&dma_chan_lock, flags);
+ return -EINVAL;
+ }
+ dma_chan[lch].callback = callback;
+ dma_chan[lch].data = data;
+ spin_unlock_irqrestore(&dma_chan_lock, flags);
+
+ return 0;
+}
+