For the case where the pci-epf-test driver uses DMA for transferring data to the root complex device, dma_map_single() is used to map virtual address to a physical address (address accessible by DMA controller) and provided to the DMAengine API for transferring data. Here instead of using the PCIe endpoint controller's 'dev' for dma_map_single(), provide DMA channel's 'dev' for dma_map_single() since the data transfer is actually done by DMA. Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx> --- Changes from v1: Use dmaengine_get_dma_device() to get dma device from channel V1: https://lore.kernel.org/r/20211115044944.31103-1-kishon@xxxxxx drivers/pci/endpoint/functions/pci-epf-test.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c index 90d84d3bc868..51f5b0b7b225 100644 --- a/drivers/pci/endpoint/functions/pci-epf-test.c +++ b/drivers/pci/endpoint/functions/pci-epf-test.c @@ -314,12 +314,12 @@ static int pci_epf_test_read(struct pci_epf_test *epf_test) u32 crc32; bool use_dma; phys_addr_t phys_addr; + struct device *dma_dev; phys_addr_t dst_phys_addr; struct timespec64 start, end; struct pci_epf *epf = epf_test->epf; struct device *dev = &epf->dev; struct pci_epc *epc = epf->epc; - struct device *dma_dev = epf->epc->dev.parent; enum pci_barno test_reg_bar = epf_test->test_reg_bar; struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar]; @@ -353,6 +353,7 @@ static int pci_epf_test_read(struct pci_epf_test *epf_test) goto err_dma_map; } + dma_dev = dmaengine_get_dma_device(epf_test->dma_chan); dst_phys_addr = dma_map_single(dma_dev, buf, reg->size, DMA_FROM_DEVICE); if (dma_mapping_error(dma_dev, dst_phys_addr)) { @@ -402,12 +403,12 @@ static int pci_epf_test_write(struct pci_epf_test *epf_test) void *buf; bool use_dma; phys_addr_t phys_addr; + struct device *dma_dev; phys_addr_t src_phys_addr; struct timespec64 start, end; struct pci_epf *epf = epf_test->epf; struct device *dev = &epf->dev; struct pci_epc *epc = epf->epc; - struct device *dma_dev = epf->epc->dev.parent; enum pci_barno test_reg_bar = epf_test->test_reg_bar; struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar]; @@ -444,6 +445,7 @@ static int pci_epf_test_write(struct pci_epf_test *epf_test) goto err_map_addr; } + dma_dev = dmaengine_get_dma_device(epf_test->dma_chan); src_phys_addr = dma_map_single(dma_dev, buf, reg->size, DMA_TO_DEVICE); if (dma_mapping_error(dma_dev, src_phys_addr)) { -- 2.17.1
