dmaengine: ti: k3-udma-glue: Add function to request TX chan for thread ID

The existing function k3_udma_glue_request_tx_chn() supports requesting
a TX DMA channel by its name. Add a new function to request TX DMA channel
for a given thread ID, named k3_udma_glue_request_tx_chn_for_thread_id().
Also, export it for use by drivers which are probed by alternate methods
(non device-tree) but still wish to make use of the existing DMA APIs. Such
drivers could be informed about the thread ID corresponding to the TX DMA
channel by RPMsg for example.

Since the new function k3_udma_glue_request_tx_chn_for_thread_id() reuses
most of the code in k3_udma_glue_request_tx_chn(), create a new function
for the common code, named k3_udma_glue_request_tx_chn_common().

Signed-off-by: Siddharth Vadapalli <[email protected]>
Acked-by: Peter Ujfalusi <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>

Author: Siddharth-Vadapalli-at-TI

drivers/dma/ti/k3-udma-glue.c

@@ -274,29 +274,13 @@ static int k3_udma_glue_cfg_tx_chn(struct k3_udma_glue_tx_channel *tx_chn)
 	return tisci_rm->tisci_udmap_ops->tx_ch_cfg(tisci_rm->tisci, &req);
 }
 
-struct k3_udma_glue_tx_channel *k3_udma_glue_request_tx_chn(struct device *dev,
-		const char *name, struct k3_udma_glue_tx_channel_cfg *cfg)
+static int
+k3_udma_glue_request_tx_chn_common(struct device *dev,
+				   struct k3_udma_glue_tx_channel *tx_chn,
+				   struct k3_udma_glue_tx_channel_cfg *cfg)
 {
-	struct k3_udma_glue_tx_channel *tx_chn;
 	int ret;
 
-	tx_chn = devm_kzalloc(dev, sizeof(*tx_chn), GFP_KERNEL);
-	if (!tx_chn)
-		return ERR_PTR(-ENOMEM);
-
-	tx_chn->common.dev = dev;
-	tx_chn->common.swdata_size = cfg->swdata_size;
-	tx_chn->tx_pause_on_err = cfg->tx_pause_on_err;
-	tx_chn->tx_filt_einfo = cfg->tx_filt_einfo;
-	tx_chn->tx_filt_pswords = cfg->tx_filt_pswords;
-	tx_chn->tx_supr_tdpkt = cfg->tx_supr_tdpkt;
-
-	/* parse of udmap channel */
-	ret = of_k3_udma_glue_parse_chn(dev->of_node, name,
-					&tx_chn->common, true);
-	if (ret)
-		goto err;
-
 	tx_chn->common.hdesc_size = cppi5_hdesc_calc_size(tx_chn->common.epib,
 						tx_chn->common.psdata_size,
 						tx_chn->common.swdata_size);
@@ -312,7 +296,7 @@ struct k3_udma_glue_tx_channel *k3_udma_glue_request_tx_chn(struct device *dev,
 	if (IS_ERR(tx_chn->udma_tchanx)) {
 		ret = PTR_ERR(tx_chn->udma_tchanx);
 		dev_err(dev, "UDMAX tchanx get err %d\n", ret);
-		goto err;
+		return ret;
 	}
 	tx_chn->udma_tchan_id = xudma_tchan_get_id(tx_chn->udma_tchanx);
 
@@ -325,7 +309,7 @@ struct k3_udma_glue_tx_channel *k3_udma_glue_request_tx_chn(struct device *dev,
 		dev_err(dev, "Channel Device registration failed %d\n", ret);
 		put_device(&tx_chn->common.chan_dev);
 		tx_chn->common.chan_dev.parent = NULL;
-		goto err;
+		return ret;
 	}
 
 	if (xudma_is_pktdma(tx_chn->common.udmax)) {
@@ -349,7 +333,7 @@ struct k3_udma_glue_tx_channel *k3_udma_glue_request_tx_chn(struct device *dev,
 					     &tx_chn->ringtxcq);
 	if (ret) {
 		dev_err(dev, "Failed to get TX/TXCQ rings %d\n", ret);
-		goto err;
+		return ret;
 	}
 
 	/* Set the dma_dev for the rings to be configured */
@@ -365,13 +349,13 @@ struct k3_udma_glue_tx_channel *k3_udma_glue_request_tx_chn(struct device *dev,
 	ret = k3_ringacc_ring_cfg(tx_chn->ringtx, &cfg->tx_cfg);
 	if (ret) {
 		dev_err(dev, "Failed to cfg ringtx %d\n", ret);
-		goto err;
+		return ret;
 	}
 
 	ret = k3_ringacc_ring_cfg(tx_chn->ringtxcq, &cfg->txcq_cfg);
 	if (ret) {
 		dev_err(dev, "Failed to cfg ringtx %d\n", ret);
-		goto err;
+		return ret;
 	}
 
 	/* request and cfg psi-l */
@@ -382,11 +366,42 @@ struct k3_udma_glue_tx_channel *k3_udma_glue_request_tx_chn(struct device *dev,
 	ret = k3_udma_glue_cfg_tx_chn(tx_chn);
 	if (ret) {
 		dev_err(dev, "Failed to cfg tchan %d\n", ret);
-		goto err;
+		return ret;
 	}
 
 	k3_udma_glue_dump_tx_chn(tx_chn);
 
+	return 0;
+}
+
+struct k3_udma_glue_tx_channel *
+k3_udma_glue_request_tx_chn(struct device *dev, const char *name,
+			    struct k3_udma_glue_tx_channel_cfg *cfg)
+{
+	struct k3_udma_glue_tx_channel *tx_chn;
+	int ret;
+
+	tx_chn = devm_kzalloc(dev, sizeof(*tx_chn), GFP_KERNEL);
+	if (!tx_chn)
+		return ERR_PTR(-ENOMEM);
+
+	tx_chn->common.dev = dev;
+	tx_chn->common.swdata_size = cfg->swdata_size;
+	tx_chn->tx_pause_on_err = cfg->tx_pause_on_err;
+	tx_chn->tx_filt_einfo = cfg->tx_filt_einfo;
+	tx_chn->tx_filt_pswords = cfg->tx_filt_pswords;
+	tx_chn->tx_supr_tdpkt = cfg->tx_supr_tdpkt;
+
+	/* parse of udmap channel */
+	ret = of_k3_udma_glue_parse_chn(dev->of_node, name,
+					&tx_chn->common, true);
+	if (ret)
+		goto err;
+
+	ret = k3_udma_glue_request_tx_chn_common(dev, tx_chn, cfg);
+	if (ret)
+		goto err;
+
 	return tx_chn;
 
 err:
@@ -395,6 +410,41 @@ struct k3_udma_glue_tx_channel *k3_udma_glue_request_tx_chn(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(k3_udma_glue_request_tx_chn);
 
+struct k3_udma_glue_tx_channel *
+k3_udma_glue_request_tx_chn_for_thread_id(struct device *dev,
+					  struct k3_udma_glue_tx_channel_cfg *cfg,
+					  struct device_node *udmax_np, u32 thread_id)
+{
+	struct k3_udma_glue_tx_channel *tx_chn;
+	int ret;
+
+	tx_chn = devm_kzalloc(dev, sizeof(*tx_chn), GFP_KERNEL);
+	if (!tx_chn)
+		return ERR_PTR(-ENOMEM);
+
+	tx_chn->common.dev = dev;
+	tx_chn->common.swdata_size = cfg->swdata_size;
+	tx_chn->tx_pause_on_err = cfg->tx_pause_on_err;
+	tx_chn->tx_filt_einfo = cfg->tx_filt_einfo;
+	tx_chn->tx_filt_pswords = cfg->tx_filt_pswords;
+	tx_chn->tx_supr_tdpkt = cfg->tx_supr_tdpkt;
+
+	ret = of_k3_udma_glue_parse_chn_by_id(udmax_np, &tx_chn->common, true, thread_id);
+	if (ret)
+		goto err;
+
+	ret = k3_udma_glue_request_tx_chn_common(dev, tx_chn, cfg);
+	if (ret)
+		goto err;
+
+	return tx_chn;
+
+err:
+	k3_udma_glue_release_tx_chn(tx_chn);
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(k3_udma_glue_request_tx_chn_for_thread_id);
+
 void k3_udma_glue_release_tx_chn(struct k3_udma_glue_tx_channel *tx_chn)
 {
 	if (tx_chn->psil_paired) {

include/linux/dma/k3-udma-glue.h

@@ -26,6 +26,11 @@ struct k3_udma_glue_tx_channel;
 struct k3_udma_glue_tx_channel *k3_udma_glue_request_tx_chn(struct device *dev,
 		const char *name, struct k3_udma_glue_tx_channel_cfg *cfg);
 
+struct k3_udma_glue_tx_channel *
+k3_udma_glue_request_tx_chn_for_thread_id(struct device *dev,
+					  struct k3_udma_glue_tx_channel_cfg *cfg,
+					  struct device_node *udmax_np, u32 thread_id);
+
 void k3_udma_glue_release_tx_chn(struct k3_udma_glue_tx_channel *tx_chn);
 int k3_udma_glue_push_tx_chn(struct k3_udma_glue_tx_channel *tx_chn,
 			     struct cppi5_host_desc_t *desc_tx,