audio: host-zephyr: rework calls to DMA driver, remove channel pointer

For historical reasons, host-zephyr has somewhat complicated code to
manage the DMA channel instance information. When a DMA channel is allocated,
a pointer to the system DMA channel table is acquired and some additional
information is stored per channel. This is however redundant as the only
piece of information actually needed is the channel index.

Simplify the code by not storing the channel pointer anymore, but
rather just store the channel index and use that in all calls to the
DMA driver.

Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>

Author: kv2019i

src/audio/copier/host_copier.h

@@ -54,10 +54,11 @@ struct host_data {
 	/* local DMA config */
 #if CONFIG_ZEPHYR_NATIVE_DRIVERS
 	struct sof_dma *dma;
+	int chan_index;
 #else
 	struct dma *dma;
-#endif
 	struct dma_chan_data *chan;
+#endif
 	struct dma_sg_config config;
 #ifdef __ZEPHYR__
 	struct dma_config z_config;

src/audio/host-zephyr.c

@@ -84,7 +84,7 @@ static int host_dma_set_config_and_copy(struct host_data *hd, struct comp_dev *d
 	local_elem->size = bytes;
 
 	/* reconfigure transfer */
-	ret = sof_dma_config(hd->chan->dma, hd->chan->index, &hd->z_config);
+	ret = sof_dma_config(hd->dma, hd->chan_index, &hd->z_config);
 	if (ret < 0) {
 		comp_err(dev, "dma_config() failed, ret = %d",
 			 ret);
@@ -93,7 +93,7 @@ static int host_dma_set_config_and_copy(struct host_data *hd, struct comp_dev *d
 
 	cb(dev, bytes);
 
-	ret = sof_dma_reload(hd->chan->dma, hd->chan->index, bytes);
+	ret = sof_dma_reload(hd->dma, hd->chan_index, bytes);
 	if (ret < 0) {
 		comp_err(dev, "dma_copy() failed, ret = %d",
 			 ret);
@@ -223,15 +223,15 @@ static int host_copy_one_shot(struct host_data *hd, struct comp_dev *dev, copy_c
 	hd->z_config.head_block->block_size = local_elem->size;
 
 	/* reconfigure transfer */
-	ret = sof_dma_config(hd->chan->dma, hd->chan->index, &hd->z_config);
+	ret = sof_dma_config(hd->dma, hd->chan_index, &hd->z_config);
 	if (ret < 0) {
 		comp_err(dev, "dma_config() failed, ret = %u", ret);
 		return ret;
 	}
 
 	cb(dev, copy_bytes);
 
-	ret = sof_dma_reload(hd->chan->dma, hd->chan->index, copy_bytes);
+	ret = sof_dma_reload(hd->dma, hd->chan_index, copy_bytes);
 	if (ret < 0)
 		comp_err(dev, "dma_copy() failed, ret = %u", ret);
 
@@ -369,7 +369,7 @@ static void host_dma_cb(struct comp_dev *dev, size_t bytes)
 /* get status from dma and check for xrun */
 static int host_get_status(struct comp_dev *dev, struct host_data *hd, struct dma_status *stat)
 {
-	int ret = sof_dma_get_status(hd->chan->dma, hd->chan->index, stat);
+	int ret = sof_dma_get_status(hd->dma, hd->chan_index, stat);
 #if CONFIG_XRUN_NOTIFICATIONS_ENABLE
 	if (ret == -EPIPE && !hd->xrun_notification_sent) {
 		hd->xrun_notification_sent = send_copier_gateway_xrun_notif_msg
@@ -556,7 +556,7 @@ static int host_copy_normal(struct host_data *hd, struct comp_dev *dev, copy_cal
 	if (!copy_bytes) {
 		if (hd->partial_size != 0) {
 			if (stream_sync(hd, dev)) {
-				ret = sof_dma_reload(hd->chan->dma, hd->chan->index,
+				ret = sof_dma_reload(hd->dma, hd->chan_index,
 						     hd->partial_size);
 				if (ret < 0)
 					comp_err(dev, "dma_reload() failed, ret = %u", ret);
@@ -583,7 +583,7 @@ static int host_copy_normal(struct host_data *hd, struct comp_dev *dev, copy_cal
 	    hd->dma_buffer_size - hd->partial_size <=
 	    (2 + threshold) * hd->period_bytes) {
 		if (stream_sync(hd, dev)) {
-			ret = sof_dma_reload(hd->chan->dma, hd->chan->index,
+			ret = sof_dma_reload(hd->dma, hd->chan_index,
 					     hd->partial_size);
 			if (ret < 0)
 				comp_err(dev, "dma_reload() failed, ret = %u", ret);
@@ -651,22 +651,22 @@ int host_common_trigger(struct host_data *hd, struct comp_dev *dev, int cmd)
 	if (cmd != COMP_TRIGGER_START && hd->copy_type == COMP_COPY_ONE_SHOT)
 		return ret;
 
-	if (!hd->chan) {
+	if (hd->chan_index == -EINVAL) {
 		comp_err(dev, "no dma channel configured");
 		return -EINVAL;
 	}
 
 	switch (cmd) {
 	case COMP_TRIGGER_START:
 		hd->partial_size = 0;
-		ret = sof_dma_start(hd->chan->dma, hd->chan->index);
+		ret = sof_dma_start(hd->dma, hd->chan_index);
 		if (ret < 0)
 			comp_err(dev, "dma_start() failed, ret = %u",
 				 ret);
 		break;
 	case COMP_TRIGGER_STOP:
 	case COMP_TRIGGER_XRUN:
-		ret = sof_dma_stop(hd->chan->dma, hd->chan->index);
+		ret = sof_dma_stop(hd->dma, hd->chan_index);
 		if (ret < 0)
 			comp_err(dev, "dma stop failed: %d",
 				 ret);
@@ -726,7 +726,7 @@ __cold int host_common_new(struct host_data *hd, struct comp_dev *dev,
 		sof_dma_put(hd->dma);
 		return -ENOMEM;
 	}
-	hd->chan = NULL;
+	hd->chan_index = -EINVAL;
 	hd->copy_type = COMP_COPY_NORMAL;
 
 	return 0;
@@ -865,7 +865,7 @@ int host_common_params(struct host_data *hd, struct comp_dev *dev,
 	uint32_t buffer_size_preferred;
 	uint32_t addr_align;
 	uint32_t align;
-	int i, channel, err;
+	int i, err;
 	bool is_scheduling_source = dev == dev->pipeline->sched_comp;
 	uint32_t round_up_size;
 
@@ -1001,22 +1001,16 @@ int host_common_params(struct host_data *hd, struct comp_dev *dev,
 	/* get DMA channel from DMAC
 	 * note: stream_tag is ignored by dw-dma
 	 */
-	channel = sof_dma_request_channel(hd->dma, hda_chan);
-	if (channel < 0) {
+	hd->chan_index = sof_dma_request_channel(hd->dma, hda_chan);
+	if (hd->chan_index < 0) {
 		comp_err(dev, "requested channel %d is busy", hda_chan);
 		return -ENODEV;
 	}
-	hd->chan = &hd->dma->chan[channel];
 
 	uint32_t buffer_addr = 0;
 	uint32_t buffer_bytes = 0;
 	uint32_t addr;
 
-	hd->chan->direction = config->direction;
-	hd->chan->desc_count = config->elem_array.count;
-	hd->chan->is_scheduling_source = config->is_scheduling_source;
-	hd->chan->period = config->period;
-
 	memset(dma_cfg, 0, sizeof(*dma_cfg));
 
 	dma_block_cfg = rzalloc(SOF_MEM_FLAG_USER,
@@ -1063,7 +1057,7 @@ int host_common_params(struct host_data *hd, struct comp_dev *dev,
 		break;
 	}
 
-	err = sof_dma_config(hd->chan->dma, hd->chan->index, dma_cfg);
+	err = sof_dma_config(hd->dma, hd->chan_index, dma_cfg);
 	if (err < 0) {
 		comp_err(dev, "dma_config() failed");
 		goto err_free_block_cfg;
@@ -1095,7 +1089,7 @@ int host_common_params(struct host_data *hd, struct comp_dev *dev,
 		 */
 		struct io_perf_data_item init_data = {
 			IO_PERF_HDA_ID,
-			hd->chan->index,
+			hd->chan_index,
 			params->direction,
 			IO_PERF_POWERED_UP_ENABLED,
 			IO_PERF_D0IX_POWER_MODE,
@@ -1111,8 +1105,8 @@ int host_common_params(struct host_data *hd, struct comp_dev *dev,
 	dma_cfg->head_block = NULL;
 	rfree(dma_block_cfg);
 err_release_channel:
-	sof_dma_release_channel(hd->dma, hd->chan->index);
-	hd->chan = NULL;
+	sof_dma_release_channel(hd->dma, hd->chan_index);
+	hd->chan_index = -EINVAL;
 
 	return err;
 }
@@ -1170,10 +1164,10 @@ static int host_position(struct comp_dev *dev,
 
 void host_common_reset(struct host_data *hd, uint16_t state)
 {
-	if (hd->chan) {
-		sof_dma_stop(hd->chan->dma, hd->chan->index);
-		sof_dma_release_channel(hd->dma, hd->chan->index);
-		hd->chan = NULL;
+	if (hd->chan_index != -EINVAL) {
+		sof_dma_stop(hd->dma, hd->chan_index);
+		sof_dma_release_channel(hd->dma, hd->chan_index);
+		hd->chan_index = -EINVAL;
 	}
 
 	/* free all DMA elements */