[PATCH v10 29/30] media: pci: fix common ALSA DMA-mapping related codes

Marek Szyprowski m.szyprowski at samsung.com
Fri Sep 4 09:17:10 EDT 2020


The Documentation/DMA-API-HOWTO.txt states that dma_map_sg returns the
numer of the created entries in the DMA address space. However the
subsequent calls to dma_sync_sg_for_{device,cpu} and dma_unmap_sg must be
called with the original number of entries passed to dma_map_sg. The
sg_table->nents in turn holds the result of the dma_map_sg call as stated
in include/linux/scatterlist.h. Adapt the code to obey those rules.

While touching this code, update it to use the modern DMA_FROM_DEVICE
definitions.

Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
---
 drivers/media/pci/cx23885/cx23885-alsa.c | 4 ++--
 drivers/media/pci/cx25821/cx25821-alsa.c | 4 ++--
 drivers/media/pci/cx88/cx88-alsa.c       | 6 +++---
 drivers/media/pci/saa7134/saa7134-alsa.c | 4 ++--
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/media/pci/cx23885/cx23885-alsa.c b/drivers/media/pci/cx23885/cx23885-alsa.c
index df44ed7393a0..c797bff6eebb 100644
--- a/drivers/media/pci/cx23885/cx23885-alsa.c
+++ b/drivers/media/pci/cx23885/cx23885-alsa.c
@@ -113,7 +113,7 @@ static int cx23885_alsa_dma_map(struct cx23885_audio_dev *dev)
 	struct cx23885_audio_buffer *buf = dev->buf;
 
 	buf->sglen = dma_map_sg(&dev->pci->dev, buf->sglist,
-			buf->nr_pages, PCI_DMA_FROMDEVICE);
+			buf->nr_pages, DMA_FROM_DEVICE);
 
 	if (0 == buf->sglen) {
 		pr_warn("%s: cx23885_alsa_map_sg failed\n", __func__);
@@ -129,7 +129,7 @@ static int cx23885_alsa_dma_unmap(struct cx23885_audio_dev *dev)
 	if (!buf->sglen)
 		return 0;
 
-	dma_unmap_sg(&dev->pci->dev, buf->sglist, buf->sglen, PCI_DMA_FROMDEVICE);
+	dma_unmap_sg(&dev->pci->dev, buf->sglist, buf->nr_pages, DMA_FROM_DEVICE);
 	buf->sglen = 0;
 	return 0;
 }
diff --git a/drivers/media/pci/cx25821/cx25821-alsa.c b/drivers/media/pci/cx25821/cx25821-alsa.c
index 301616426d8a..8da31c953b02 100644
--- a/drivers/media/pci/cx25821/cx25821-alsa.c
+++ b/drivers/media/pci/cx25821/cx25821-alsa.c
@@ -177,7 +177,7 @@ static int cx25821_alsa_dma_map(struct cx25821_audio_dev *dev)
 	struct cx25821_audio_buffer *buf = dev->buf;
 
 	buf->sglen = dma_map_sg(&dev->pci->dev, buf->sglist,
-			buf->nr_pages, PCI_DMA_FROMDEVICE);
+			buf->nr_pages, DMA_FROM_DEVICE);
 
 	if (0 == buf->sglen) {
 		pr_warn("%s: cx25821_alsa_map_sg failed\n", __func__);
@@ -193,7 +193,7 @@ static int cx25821_alsa_dma_unmap(struct cx25821_audio_dev *dev)
 	if (!buf->sglen)
 		return 0;
 
-	dma_unmap_sg(&dev->pci->dev, buf->sglist, buf->sglen, PCI_DMA_FROMDEVICE);
+	dma_unmap_sg(&dev->pci->dev, buf->sglist, buf->nr_pages, DMA_FROM_DEVICE);
 	buf->sglen = 0;
 	return 0;
 }
diff --git a/drivers/media/pci/cx88/cx88-alsa.c b/drivers/media/pci/cx88/cx88-alsa.c
index 7d7aceecc985..d38633bc1330 100644
--- a/drivers/media/pci/cx88/cx88-alsa.c
+++ b/drivers/media/pci/cx88/cx88-alsa.c
@@ -316,7 +316,7 @@ static int cx88_alsa_dma_map(struct cx88_audio_dev *dev)
 	struct cx88_audio_buffer *buf = dev->buf;
 
 	buf->sglen = dma_map_sg(&dev->pci->dev, buf->sglist,
-			buf->nr_pages, PCI_DMA_FROMDEVICE);
+			buf->nr_pages, DMA_FROM_DEVICE);
 
 	if (buf->sglen == 0) {
 		pr_warn("%s: cx88_alsa_map_sg failed\n", __func__);
@@ -332,8 +332,8 @@ static int cx88_alsa_dma_unmap(struct cx88_audio_dev *dev)
 	if (!buf->sglen)
 		return 0;
 
-	dma_unmap_sg(&dev->pci->dev, buf->sglist, buf->sglen,
-		     PCI_DMA_FROMDEVICE);
+	dma_unmap_sg(&dev->pci->dev, buf->sglist, buf->nr_pages,
+		     DMA_FROM_DEVICE);
 	buf->sglen = 0;
 	return 0;
 }
diff --git a/drivers/media/pci/saa7134/saa7134-alsa.c b/drivers/media/pci/saa7134/saa7134-alsa.c
index 544ca57eee75..707ca77221dc 100644
--- a/drivers/media/pci/saa7134/saa7134-alsa.c
+++ b/drivers/media/pci/saa7134/saa7134-alsa.c
@@ -297,7 +297,7 @@ static int saa7134_alsa_dma_map(struct saa7134_dev *dev)
 	struct saa7134_dmasound *dma = &dev->dmasound;
 
 	dma->sglen = dma_map_sg(&dev->pci->dev, dma->sglist,
-			dma->nr_pages, PCI_DMA_FROMDEVICE);
+			dma->nr_pages, DMA_FROM_DEVICE);
 
 	if (0 == dma->sglen) {
 		pr_warn("%s: saa7134_alsa_map_sg failed\n", __func__);
@@ -313,7 +313,7 @@ static int saa7134_alsa_dma_unmap(struct saa7134_dev *dev)
 	if (!dma->sglen)
 		return 0;
 
-	dma_unmap_sg(&dev->pci->dev, dma->sglist, dma->sglen, PCI_DMA_FROMDEVICE);
+	dma_unmap_sg(&dev->pci->dev, dma->sglist, dma->nr_pages, DMA_FROM_DEVICE);
 	dma->sglen = 0;
 	return 0;
 }
-- 
2.17.1




More information about the linux-arm-kernel mailing list