Merge branch 'mana-shared' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Leon Romanovsky says:

====================
net: mana: Allow variable size indirection table

Like we talked, I created new shared branch for this patch:
https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git/log/?h=mana-shared

* 'mana-shared' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
   net: mana: Allow variable size indirection table
====================

Link: https://lore.kernel.org/all/20240612183051.GE4966@unreal
Signed-off-by: Leon Romanovsky <leon@kernel.org>

1 files changed, 26 insertions, 5 deletions

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 289feccca376..9bc9fd10d538 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1220,6 +1220,11 @@ void spi_unmap_buf(struct spi_controller *ctlr, struct device *dev,
 	spi_unmap_buf_attrs(ctlr, dev, sgt, dir, 0);
 }
 
+/* Dummy SG for unidirect transfers */
+static struct scatterlist dummy_sg = {
+	.page_link = SG_END,
+};
+
 static int __spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg)
 {
 	struct device *tx_dev, *rx_dev;
@@ -1243,6 +1248,7 @@ static int __spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg)
 	else
 		rx_dev = ctlr->dev.parent;
 
+	ret = -ENOMSG;
 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
 		/* The sync is done before each transfer. */
 		unsigned long attrs = DMA_ATTR_SKIP_CPU_SYNC;
@@ -1257,6 +1263,8 @@ static int __spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg)
 						attrs);
 			if (ret != 0)
 				return ret;
+		} else {
+			xfer->tx_sg.sgl = &dummy_sg;
 		}
 
 		if (xfer->rx_buf != NULL) {
@@ -1270,8 +1278,13 @@ static int __spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg)
 
 				return ret;
 			}
+		} else {
+			xfer->rx_sg.sgl = &dummy_sg;
 		}
 	}
+	/* No transfer has been mapped, bail out with success */
+	if (ret)
+		return 0;
 
 	ctlr->cur_rx_dma_dev = rx_dev;
 	ctlr->cur_tx_dma_dev = tx_dev;
@@ -1307,7 +1320,7 @@ static int __spi_unmap_msg(struct spi_controller *ctlr, struct spi_message *msg)
 	return 0;
 }
 
-static void spi_dma_sync_for_device(struct spi_controller *ctlr,
+static void spi_dma_sync_for_device(struct spi_controller *ctlr, struct spi_message *msg,
 				    struct spi_transfer *xfer)
 {
 	struct device *rx_dev = ctlr->cur_rx_dma_dev;
@@ -1316,11 +1329,14 @@ static void spi_dma_sync_for_device(struct spi_controller *ctlr,
 	if (!ctlr->cur_msg_mapped)
 		return;
 
+	if (!ctlr->can_dma(ctlr, msg->spi, xfer))
+		return;
+
 	dma_sync_sgtable_for_device(tx_dev, &xfer->tx_sg, DMA_TO_DEVICE);
 	dma_sync_sgtable_for_device(rx_dev, &xfer->rx_sg, DMA_FROM_DEVICE);
 }
 
-static void spi_dma_sync_for_cpu(struct spi_controller *ctlr,
+static void spi_dma_sync_for_cpu(struct spi_controller *ctlr, struct spi_message *msg,
 				 struct spi_transfer *xfer)
 {
 	struct device *rx_dev = ctlr->cur_rx_dma_dev;
@@ -1329,6 +1345,9 @@ static void spi_dma_sync_for_cpu(struct spi_controller *ctlr,
 	if (!ctlr->cur_msg_mapped)
 		return;
 
+	if (!ctlr->can_dma(ctlr, msg->spi, xfer))
+		return;
+
 	dma_sync_sgtable_for_cpu(rx_dev, &xfer->rx_sg, DMA_FROM_DEVICE);
 	dma_sync_sgtable_for_cpu(tx_dev, &xfer->tx_sg, DMA_TO_DEVICE);
 }
@@ -1346,11 +1365,13 @@ static inline int __spi_unmap_msg(struct spi_controller *ctlr,
 }
 
 static void spi_dma_sync_for_device(struct spi_controller *ctrl,
+				    struct spi_message *msg,
 				    struct spi_transfer *xfer)
 {
 }
 
 static void spi_dma_sync_for_cpu(struct spi_controller *ctrl,
+				 struct spi_message *msg,
 				 struct spi_transfer *xfer)
 {
 }
@@ -1622,10 +1643,10 @@ static int spi_transfer_one_message(struct spi_controller *ctlr,
 			reinit_completion(&ctlr->xfer_completion);
 
 fallback_pio:
-			spi_dma_sync_for_device(ctlr, xfer);
+			spi_dma_sync_for_device(ctlr, msg, xfer);
 			ret = ctlr->transfer_one(ctlr, msg->spi, xfer);
 			if (ret < 0) {
-				spi_dma_sync_for_cpu(ctlr, xfer);
+				spi_dma_sync_for_cpu(ctlr, msg, xfer);
 
 				if (ctlr->cur_msg_mapped &&
 				   (xfer->error & SPI_TRANS_FAIL_NO_START)) {
@@ -1650,7 +1671,7 @@ fallback_pio:
 					msg->status = ret;
 			}
 
-			spi_dma_sync_for_cpu(ctlr, xfer);
+			spi_dma_sync_for_cpu(ctlr, msg, xfer);
 		} else {
 			if (xfer->len)
 				dev_err(&msg->spi->dev,