[PATCH 2/2] ASoC: use dma_ops of parent device for acp_audio_dma
From: Yu Zhao
Date: Tue Dec 04 2018 - 17:43:06 EST
AMD platform device acp_audio_dma can only be created by parent PCI
device driver (drivers/gpu/drm/amd/amdgpu/amdgpu_acp.c). Pass struct
device of the parent to snd_pcm_lib_preallocate_pages() so
dma_alloc_coherent() can use correct dma_ops. Otherwise, it will
use default dma_ops which is nommu_dma_ops on x86_64 even when
IOMMU is enabled and set to non passthrough mode.
Though platform device inherits some dma related fields during its
creation in mfd_add_device(), we can't simply pass its struct device
to snd_pcm_lib_preallocate_pages() because dma_ops is not among the
inherited fields. Even it were, drivers/iommu/amd_iommu.c would
ignore it because get_device_id() doesn't handle platform device.
This change shouldn't give us any trouble even struct device of the
parent becomes null or represents some non PCI device in the future,
because get_dma_ops() correctly handles null struct device or uses
the default dma_ops if struct device doesn't have it set.
Signed-off-by: Yu Zhao <yuzhao@xxxxxxxxxx>
---
sound/soc/amd/acp-pcm-dma.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/sound/soc/amd/acp-pcm-dma.c b/sound/soc/amd/acp-pcm-dma.c
index fd3db4c37882..f4011bebc7ec 100644
--- a/sound/soc/amd/acp-pcm-dma.c
+++ b/sound/soc/amd/acp-pcm-dma.c
@@ -1146,18 +1146,21 @@ static int acp_dma_new(struct snd_soc_pcm_runtime *rtd)
struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd,
DRV_NAME);
struct audio_drv_data *adata = dev_get_drvdata(component->dev);
+ struct device *parent = component->dev->parent;
switch (adata->asic_type) {
case CHIP_STONEY:
ret = snd_pcm_lib_preallocate_pages_for_all(rtd->pcm,
SNDRV_DMA_TYPE_DEV,
- NULL, ST_MIN_BUFFER,
+ parent,
+ ST_MIN_BUFFER,
ST_MAX_BUFFER);
break;
default:
ret = snd_pcm_lib_preallocate_pages_for_all(rtd->pcm,
SNDRV_DMA_TYPE_DEV,
- NULL, MIN_BUFFER,
+ parent,
+ MIN_BUFFER,
MAX_BUFFER);
break;
}
--
2.20.0.rc1.387.gf8505762e3-goog