dma: add channel release callback

This is useful for releasing channel resources "allocated" during
channel request. These resources can refer to enabled IRQs, PDs,
etc...

Signed-off-by: Laurentiu Mihalcea <[email protected]>

Author: LaurentiuM1234

include/zephyr/drivers/dma.h

@@ -352,6 +352,20 @@ typedef int (*dma_api_get_attribute)(const struct device *dev, uint32_t type, ui
 typedef bool (*dma_api_chan_filter)(const struct device *dev,
 				int channel, void *filter_param);
 
+/**
+ * @typedef dma_chan_release
+ * @brief channel release function call
+ *
+ * used to release channel resources "allocated" during the
+ * request phase. These resources can refer to enabled PDs, IRQs
+ * etc...
+ *
+ * @param dev Pointer to the DMA device instance
+ * @param channel channel id to use
+ */
+typedef void (*dma_api_chan_release)(const struct device *dev,
+				     uint32_t channel);
+
 __subsystem struct dma_driver_api {
 	dma_api_config config;
 	dma_api_reload reload;
@@ -362,6 +376,7 @@ __subsystem struct dma_driver_api {
 	dma_api_get_status get_status;
 	dma_api_get_attribute get_attribute;
 	dma_api_chan_filter chan_filter;
+	dma_api_chan_release chan_release;
 };
 /**
  * @endcond
@@ -595,13 +610,19 @@ __syscall void dma_release_channel(const struct device *dev,
 static inline void z_impl_dma_release_channel(const struct device *dev,
 					      uint32_t channel)
 {
+	const struct dma_driver_api *api =
+		(const struct dma_driver_api *)dev->api;
 	struct dma_context *dma_ctx = (struct dma_context *)dev->data;
 
 	if (dma_ctx->magic != DMA_MAGIC) {
 		return;
 	}
 
 	if ((int)channel < dma_ctx->dma_channels) {
+		if (api->chan_release) {
+			api->chan_release(dev, channel);
+		}
+
 		atomic_clear_bit(dma_ctx->atomic, channel);
 	}