diff mbox series

[v2,06/11] spi: dw-dma: Check DMA Tx-desc submission status

Message ID 20200920112322.24585-7-Sergey.Semin@baikalelectronics.ru (mailing list archive)
State Accepted
Commit 9a6471a1a2c24964838a5bfa4d374e644e9daf07
Headers show
Series spi: dw-dma: Add max SG entries burst capability support | expand

Commit Message

Serge Semin Sept. 20, 2020, 11:23 a.m. UTC
We suggest to add the dmaengine_submit() return value test for errors.  It
has been unnecessary while the driver was expected to be utilized in pair
with DW DMAC. But since now the driver can be used with any DMA engine, it
might be useful to track the errors on DMA submissions so not miss them
and get into an unpredictable driver behaviour.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>

---

Changelog v2:
- Replace negative conditional statements with the positive ones.
- Terminate the prepared descriptors on submission errors.
---
 drivers/spi/spi-dw-dma.c | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/spi/spi-dw-dma.c b/drivers/spi/spi-dw-dma.c
index 769d10ca74b4..aa3900809126 100644
--- a/drivers/spi/spi-dw-dma.c
+++ b/drivers/spi/spi-dw-dma.c
@@ -275,6 +275,8 @@  static struct dma_async_tx_descriptor *
 dw_spi_dma_submit_tx(struct dw_spi *dws, struct spi_transfer *xfer)
 {
 	struct dma_async_tx_descriptor *txdesc;
+	dma_cookie_t cookie;
+	int ret;
 
 	txdesc = dmaengine_prep_slave_sg(dws->txchan,
 				xfer->tx_sg.sgl,
@@ -287,7 +289,13 @@  dw_spi_dma_submit_tx(struct dw_spi *dws, struct spi_transfer *xfer)
 	txdesc->callback = dw_spi_dma_tx_done;
 	txdesc->callback_param = dws;
 
-	dmaengine_submit(txdesc);
+	cookie = dmaengine_submit(txdesc);
+	ret = dma_submit_error(cookie);
+	if (ret) {
+		dmaengine_terminate_sync(dws->txchan);
+		return NULL;
+	}
+
 	set_bit(TX_BUSY, &dws->dma_chan_busy);
 
 	return txdesc;
@@ -371,6 +379,8 @@  static struct dma_async_tx_descriptor *dw_spi_dma_submit_rx(struct dw_spi *dws,
 		struct spi_transfer *xfer)
 {
 	struct dma_async_tx_descriptor *rxdesc;
+	dma_cookie_t cookie;
+	int ret;
 
 	rxdesc = dmaengine_prep_slave_sg(dws->rxchan,
 				xfer->rx_sg.sgl,
@@ -383,7 +393,13 @@  static struct dma_async_tx_descriptor *dw_spi_dma_submit_rx(struct dw_spi *dws,
 	rxdesc->callback = dw_spi_dma_rx_done;
 	rxdesc->callback_param = dws;
 
-	dmaengine_submit(rxdesc);
+	cookie = dmaengine_submit(rxdesc);
+	ret = dma_submit_error(cookie);
+	if (ret) {
+		dmaengine_terminate_sync(dws->rxchan);
+		return NULL;
+	}
+
 	set_bit(RX_BUSY, &dws->dma_chan_busy);
 
 	return rxdesc;