[PATCH v4] dma: ti: k3-udma: Use ring_idx to pair k3 nav rings

[MD Danish Anwar]

Use ring_idx to pair rings. ring_idx will be same as tx flow_id for all
non-negative flow_ids. For negative flow_ids, ring_idx will be tchan->id
added with bchan_cnt.

Signed-off-by: MD Danish Anwar <danishanwar at ti.com>
---
Changes from v3 to v4:
*) No functional change. Splitted the patch out of the series as suggested
   by Nishant.

v3: https://lore.kernel.org/all/20240124064930.1787929-2-danishanwar@ti.com/

 drivers/dma/ti/k3-udma.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c
index 8a62d63dfe..eea9ec9659 100644
--- a/drivers/dma/ti/k3-udma.c
+++ b/drivers/dma/ti/k3-udma.c
@@ -876,13 +876,20 @@ static int udma_alloc_tx_resources(struct udma_chan *uc)
 {
 	struct k3_nav_ring_cfg ring_cfg;
 	struct udma_dev *ud = uc->ud;
-	int ret;
+	struct udma_tchan *tchan;
+	int ring_idx, ret;
 
 	ret = udma_get_tchan(uc);
 	if (ret)
 		return ret;
 
-	ret = k3_nav_ringacc_request_rings_pair(ud->ringacc, uc->tchan->id, -1,
+	tchan = uc->tchan;
+	if (tchan->tflow_id >= 0)
+		ring_idx = tchan->tflow_id;
+	else
+		ring_idx = ud->bchan_cnt + tchan->id;
+
+	ret = k3_nav_ringacc_request_rings_pair(ud->ringacc, ring_idx, -1,
 						&uc->tchan->t_ring,
 						&uc->tchan->tc_ring);
 	if (ret) {
-- 
2.34.1