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Groups > linux.kernel > #1231964
| From | Tiffany Lin <tiffany.lin@mediatek.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH v2] media: vb2: Fix vb2_dc_prepare do not correct sync data to device |
| Date | 2015-09-24 11:10 +0200 |
| Message-ID | <qcaHo-6Yx-25@gated-at.bofh.it> (permalink) |
| References | <qcaHo-6Yx-17@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
vb2_dc_prepare use the number of SG entries dma_map_sg_attrs return. But in dma_sync_sg_for_device, it use lengths of each SG entries before dma_map_sg_attrs. dma_map_sg_attrs will concatenate SGs until dma length > dma seg bundary. sgt->nents will less than sgt->orig_nents. Using SG entries after dma_map_sg_attrs in vb2_dc_prepare will make some SGs are not sync to device. After add DMA_ATTR_SKIP_CPU_SYNC in vb2_dc_get_userptr to remove sync data to device twice. Device randomly get incorrect data because some SGs are not sync to device. Change to use number of SG entries before dma_map_sg_attrs in vb2_dc_prepare to prevent this issue. Signed-off-by: Tiffany Lin <tiffany.lin@mediatek.com> --- drivers/media/v4l2-core/videobuf2-dma-contig.c | 4 ++-- drivers/media/v4l2-core/videobuf2-dma-sg.c | 5 ++--- 2 files changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c index 2397ceb..c5d00bd 100644 --- a/drivers/media/v4l2-core/videobuf2-dma-contig.c +++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c @@ -100,7 +100,7 @@ static void vb2_dc_prepare(void *buf_priv) if (!sgt || buf->db_attach) return; - dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); + dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir); } static void vb2_dc_finish(void *buf_priv) @@ -112,7 +112,7 @@ static void vb2_dc_finish(void *buf_priv) if (!sgt || buf->db_attach) return; - dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); + dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir); } /*********************************************/ diff --git a/drivers/media/v4l2-core/videobuf2-dma-sg.c b/drivers/media/v4l2-core/videobuf2-dma-sg.c index be7bd65..a09f7fd 100644 --- a/drivers/media/v4l2-core/videobuf2-dma-sg.c +++ b/drivers/media/v4l2-core/videobuf2-dma-sg.c @@ -1,4 +1,3 @@ -/* * videobuf2-dma-sg.c - dma scatter/gather memory allocator for videobuf2 * * Copyright (C) 2010 Samsung Electronics @@ -210,7 +209,7 @@ static void vb2_dma_sg_prepare(void *buf_priv) if (buf->db_attach) return; - dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); + dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir); } static void vb2_dma_sg_finish(void *buf_priv) @@ -222,7 +221,7 @@ static void vb2_dma_sg_finish(void *buf_priv) if (buf->db_attach) return; - dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); + dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir); } static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr, -- 1.8.1.1.dirty -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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[PATCH v2] media: vb2: Fix vb2_dc_prepare do not correct sync data to device Tiffany Lin <tiffany.lin@mediatek.com> - 2015-09-24 11:10 +0200 [PATCH v2] media: vb2: Fix vb2_dc_prepare do not correct sync data to device Tiffany Lin <tiffany.lin@mediatek.com> - 2015-09-24 11:10 +0200
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