[RFC PATCH 3/3] dmaengine: ti: k3-udma-glue: Add function to request RX channel by ID

[Siddharth Vadapalli]

The existing function k3_udma_glue_request_remote_rx_chn() supports
requesting an RX DMA channel and flow by the name of the RX DMA channel.
Add support to request RX channel by ID in the form of a new function
k3_udma_glue_request_remote_rx_chn_by_id() and export it.

Since the implementation of k3_udma_glue_request_remote_rx_chn_by_id()
reuses most of the code in k3_udma_glue_request_remote_rx_chn(), create
a new function k3_udma_glue_request_remote_rx_chn_common() for the
common code.

Signed-off-by: Siddharth Vadapalli <s-vadapalli@xxxxxx>
---
 drivers/dma/ti/k3-udma-glue.c    | 140 ++++++++++++++++++++++---------
 include/linux/dma/k3-udma-glue.h |   4 +
 2 files changed, 103 insertions(+), 41 deletions(-)

diff --git a/drivers/dma/ti/k3-udma-glue.c b/drivers/dma/ti/k3-udma-glue.c
index d3f04d446c4e..167fe77de71e 100644
--- a/drivers/dma/ti/k3-udma-glue.c
+++ b/drivers/dma/ti/k3-udma-glue.c
@@ -1076,52 +1076,21 @@ k3_udma_glue_request_rx_chn_priv(struct device *dev, const char *name,
 	return ERR_PTR(ret);
 }
 
-static struct k3_udma_glue_rx_channel *
-k3_udma_glue_request_remote_rx_chn(struct device *dev, const char *name,
-				   struct k3_udma_glue_rx_channel_cfg *cfg)
+static int
+k3_udma_glue_request_remote_rx_chn_common(struct k3_udma_glue_rx_channel *rx_chn,
+					  struct k3_udma_glue_rx_channel_cfg *cfg,
+					  struct device *dev)
 {
-	struct k3_udma_glue_rx_channel *rx_chn;
 	int ret, i;
 
-	if (cfg->flow_id_num <= 0 ||
-	    cfg->flow_id_use_rxchan_id ||
-	    cfg->def_flow_cfg ||
-	    cfg->flow_id_base < 0)
-		return ERR_PTR(-EINVAL);
-
-	/*
-	 * Remote RX channel is under control of Remote CPU core, so
-	 * Linux can only request and manipulate by dedicated RX flows
-	 */
-
-	rx_chn = devm_kzalloc(dev, sizeof(*rx_chn), GFP_KERNEL);
-	if (!rx_chn)
-		return ERR_PTR(-ENOMEM);
-
-	rx_chn->common.dev = dev;
-	rx_chn->common.swdata_size = cfg->swdata_size;
-	rx_chn->remote = true;
-	rx_chn->udma_rchan_id = -1;
-	rx_chn->flow_num = cfg->flow_id_num;
-	rx_chn->flow_id_base = cfg->flow_id_base;
-	rx_chn->psil_paired = false;
-
-	/* parse of udmap channel */
-	ret = of_k3_udma_glue_parse_chn(dev->of_node, name,
-					&rx_chn->common, false);
-	if (ret)
-		goto err;
-
 	rx_chn->common.hdesc_size = cppi5_hdesc_calc_size(rx_chn->common.epib,
-						rx_chn->common.psdata_size,
-						rx_chn->common.swdata_size);
+							  rx_chn->common.psdata_size,
+							  rx_chn->common.swdata_size);
 
 	rx_chn->flows = devm_kcalloc(dev, rx_chn->flow_num,
 				     sizeof(*rx_chn->flows), GFP_KERNEL);
-	if (!rx_chn->flows) {
-		ret = -ENOMEM;
-		goto err;
-	}
+	if (!rx_chn->flows)
+		return -ENOMEM;
 
 	rx_chn->common.chan_dev.class = &k3_udma_glue_devclass;
 	rx_chn->common.chan_dev.parent = xudma_get_device(rx_chn->common.udmax);
@@ -1132,7 +1101,7 @@ k3_udma_glue_request_remote_rx_chn(struct device *dev, const char *name,
 		dev_err(dev, "Channel Device registration failed %d\n", ret);
 		put_device(&rx_chn->common.chan_dev);
 		rx_chn->common.chan_dev.parent = NULL;
-		goto err;
+		return ret;
 	}
 
 	if (xudma_is_pktdma(rx_chn->common.udmax)) {
@@ -1144,19 +1113,108 @@ k3_udma_glue_request_remote_rx_chn(struct device *dev, const char *name,
 
 	ret = k3_udma_glue_allocate_rx_flows(rx_chn, cfg);
 	if (ret)
-		goto err;
+		return ret;
 
 	for (i = 0; i < rx_chn->flow_num; i++)
 		rx_chn->flows[i].udma_rflow_id = rx_chn->flow_id_base + i;
 
 	k3_udma_glue_dump_rx_chn(rx_chn);
 
+	return 0;
+}
+
+static struct k3_udma_glue_rx_channel *
+k3_udma_glue_request_remote_rx_chn(struct device *dev, const char *name,
+				   struct k3_udma_glue_rx_channel_cfg *cfg)
+{
+	struct k3_udma_glue_rx_channel *rx_chn;
+	int ret;
+
+	if (cfg->flow_id_num <= 0 ||
+	    cfg->flow_id_use_rxchan_id ||
+	    cfg->def_flow_cfg ||
+	    cfg->flow_id_base < 0)
+		return ERR_PTR(-EINVAL);
+
+	/*
+	 * Remote RX channel is under control of Remote CPU core, so
+	 * Linux can only request and manipulate by dedicated RX flows
+	 */
+
+	rx_chn = devm_kzalloc(dev, sizeof(*rx_chn), GFP_KERNEL);
+	if (!rx_chn)
+		return ERR_PTR(-ENOMEM);
+
+	rx_chn->common.dev = dev;
+	rx_chn->common.swdata_size = cfg->swdata_size;
+	rx_chn->remote = true;
+	rx_chn->udma_rchan_id = -1;
+	rx_chn->flow_num = cfg->flow_id_num;
+	rx_chn->flow_id_base = cfg->flow_id_base;
+	rx_chn->psil_paired = false;
+
+	/* parse of udmap channel */
+	ret = of_k3_udma_glue_parse_chn(dev->of_node, name,
+					&rx_chn->common, false);
+	if (ret)
+		goto err;
+
+	ret = k3_udma_glue_request_remote_rx_chn_common(rx_chn, cfg, dev);
+	if (ret)
+		goto err;
+
+	return rx_chn;
+
+err:
+	k3_udma_glue_release_rx_chn(rx_chn);
+	return ERR_PTR(ret);
+}
+
+struct k3_udma_glue_rx_channel *
+k3_udma_glue_request_remote_rx_chn_by_id(struct device *dev, struct device_node *udmax_np,
+					 struct k3_udma_glue_rx_channel_cfg *cfg, u32 thread_id)
+{
+	struct k3_udma_glue_rx_channel *rx_chn;
+	int ret;
+
+	if (cfg->flow_id_num <= 0 ||
+	    cfg->flow_id_use_rxchan_id ||
+	    cfg->def_flow_cfg ||
+	    cfg->flow_id_base < 0)
+		return ERR_PTR(-EINVAL);
+
+	/*
+	 * Remote RX channel is under control of Remote CPU core, so
+	 * Linux can only request and manipulate by dedicated RX flows
+	 */
+
+	rx_chn = devm_kzalloc(dev, sizeof(*rx_chn), GFP_KERNEL);
+	if (!rx_chn)
+		return ERR_PTR(-ENOMEM);
+
+	rx_chn->common.dev = dev;
+	rx_chn->common.swdata_size = cfg->swdata_size;
+	rx_chn->remote = true;
+	rx_chn->udma_rchan_id = -1;
+	rx_chn->flow_num = cfg->flow_id_num;
+	rx_chn->flow_id_base = cfg->flow_id_base;
+	rx_chn->psil_paired = false;
+
+	ret = of_k3_udma_glue_parse_chn_by_id(udmax_np, &rx_chn->common, false, thread_id);
+	if (ret)
+		goto err;
+
+	ret = k3_udma_glue_request_remote_rx_chn_common(rx_chn, cfg, dev);
+	if (ret)
+		goto err;
+
 	return rx_chn;
 
 err:
 	k3_udma_glue_release_rx_chn(rx_chn);
 	return ERR_PTR(ret);
 }
+EXPORT_SYMBOL_GPL(k3_udma_glue_request_remote_rx_chn_by_id);
 
 struct k3_udma_glue_rx_channel *
 k3_udma_glue_request_rx_chn(struct device *dev, const char *name,
diff --git a/include/linux/dma/k3-udma-glue.h b/include/linux/dma/k3-udma-glue.h
index 6205d84430ca..a81d1b8f889c 100644
--- a/include/linux/dma/k3-udma-glue.h
+++ b/include/linux/dma/k3-udma-glue.h
@@ -108,6 +108,10 @@ struct k3_udma_glue_rx_channel_cfg {
 
 struct k3_udma_glue_rx_channel;
 
+struct k3_udma_glue_rx_channel *
+k3_udma_glue_request_remote_rx_chn_by_id(struct device *dev, struct device_node *udmax_np,
+					 struct k3_udma_glue_rx_channel_cfg *cfg, u32 thread_id);
+
 struct k3_udma_glue_rx_channel *k3_udma_glue_request_rx_chn(
 		struct device *dev,
 		const char *name,
-- 
2.34.1