Patch "dmaengine: ti: k3-udma: Report short packet errors" has been added to the 6.6-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    dmaengine: ti: k3-udma: Report short packet errors

to the 6.6-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     dmaengine-ti-k3-udma-report-short-packet-errors.patch
and it can be found in the queue-6.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 92559ec3c2ced4c8c94230c98c871b8d7223b4f3
Author: Jai Luthra <j-luthra@xxxxxx>
Date:   Wed Jan 3 14:37:55 2024 +0530

    dmaengine: ti: k3-udma: Report short packet errors
    
    [ Upstream commit bc9847c9ba134cfe3398011e343dcf6588c1c902 ]
    
    Propagate the TR response status to the device using BCDMA
    split-channels. For example CSI-RX driver should be able to check if a
    frame was not transferred completely (short packet) and needs to be
    discarded.
    
    Fixes: 25dcb5dd7b7c ("dmaengine: ti: New driver for K3 UDMA")
    Signed-off-by: Jai Luthra <j-luthra@xxxxxx>
    Acked-by: Peter Ujfalusi <peter.ujfalusi@xxxxxxxxx>
    Link: https://lore.kernel.org/r/20240103-tr_resp_err-v1-1-2fdf6d48ab92@xxxxxx
    Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c
index 30fd2f386f36..037f1408e798 100644
--- a/drivers/dma/ti/k3-udma.c
+++ b/drivers/dma/ti/k3-udma.c
@@ -3968,6 +3968,7 @@ static void udma_desc_pre_callback(struct virt_dma_chan *vc,
 {
 	struct udma_chan *uc = to_udma_chan(&vc->chan);
 	struct udma_desc *d;
+	u8 status;
 
 	if (!vd)
 		return;
@@ -3977,12 +3978,12 @@ static void udma_desc_pre_callback(struct virt_dma_chan *vc,
 	if (d->metadata_size)
 		udma_fetch_epib(uc, d);
 
-	/* Provide residue information for the client */
 	if (result) {
 		void *desc_vaddr = udma_curr_cppi5_desc_vaddr(d, d->desc_idx);
 
 		if (cppi5_desc_get_type(desc_vaddr) ==
 		    CPPI5_INFO0_DESC_TYPE_VAL_HOST) {
+			/* Provide residue information for the client */
 			result->residue = d->residue -
 					  cppi5_hdesc_get_pktlen(desc_vaddr);
 			if (result->residue)
@@ -3991,7 +3992,12 @@ static void udma_desc_pre_callback(struct virt_dma_chan *vc,
 				result->result = DMA_TRANS_NOERROR;
 		} else {
 			result->residue = 0;
-			result->result = DMA_TRANS_NOERROR;
+			/* Propagate TR Response errors to the client */
+			status = d->hwdesc[0].tr_resp_base->status;
+			if (status)
+				result->result = DMA_TRANS_ABORTED;
+			else
+				result->result = DMA_TRANS_NOERROR;
 		}
 	}
 }