According to the DMA API data has to be synchronised before starting
a DMA transfer to device and after completing a DMA transfer from device.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@xxxxxx>
---
drivers/mmc/host/mxcmmc.c | 18 ++++++++++++------
1 files changed, 12 insertions(+), 6 deletions(-)
diff --git a/drivers/mmc/host/mxcmmc.c b/drivers/mmc/host/mxcmmc.c
index f7199c8..31dfc7b 100644
--- a/drivers/mmc/host/mxcmmc.c
+++ b/drivers/mmc/host/mxcmmc.c
@@ -326,6 +326,7 @@ static inline void mxcmci_swap_buffers(struct mmc_data *data) {}
static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
{
+ struct device *dev = host->dma->device->dev;
unsigned int nob = data->blocks;
unsigned int blksz = data->blksz;
unsigned int datasize = nob * blksz;
@@ -363,18 +364,20 @@ static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
mxcmci_swap_buffers(data);
}
- nents = dma_map_sg(host->dma->device->dev, data->sg,
- data->sg_len, host->dma_dir);
+ nents = dma_map_sg(dev, data->sg, data->sg_len, host->dma_dir);
if (nents != data->sg_len)
return -EINVAL;
+ if (data->flags & MMC_DATA_WRITE)
+ dma_sync_sg_for_device(dev, data->sg, data->sg_len,
+ host->dma_dir);
+
host->desc = dmaengine_prep_slave_sg(host->dma,
data->sg, data->sg_len, slave_dirn,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!host->desc) {
- dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
- host->dma_dir);
+ dma_unmap_sg(dev, data->sg, data->sg_len, host->dma_dir);
host->do_dma = 0;
return 0; /* Fall back to PIO */
}
@@ -487,8 +490,11 @@ static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
int data_error;
if (mxcmci_use_dma(host)) {
- dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
- host->dma_dir);
+ struct device *dev = host->dma->device->dev;
+ dma_unmap_sg(dev, data->sg, data->sg_len, host->dma_dir);
+ if (host->dma_dir == DMA_FROM_DEVICE)
+ dma_sync_sg_for_cpu(dev, data->sg, data->sg_len,
+ host->dma_dir);
mxcmci_swap_buffers(data);
}
--
1.7.2.5
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