Subject: [PATCH v5 8/9] PCI: epf-mhi: Use dmaengine_prep_config_single() to simplify code

From: Frank Li <[email-masked]>
Date: Tue, 12 May 2026 12:42:06 -0400

Use dmaengine_prep_config_single() to simplify
pci_epf_mhi_edma_read[_sync]() and pci_epf_mhi_edma_write[_sync]().

No functional change.

Tested-by: Niklas Cassel <[email-masked]>
Acked-by: Manivannan Sadhasivam <[email-masked]>
Signed-off-by: Frank Li <[email-masked]>
---
Keep mutex lock because sync with other function.
---
 drivers/pci/endpoint/functions/pci-epf-mhi.c | 52 +++++++++-------------------
 1 file changed, 16 insertions(+), 36 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c
index 7f5326925ed54abf4ae75c465dfe0a9bab37ce40..c3e3b58fb86cd75e175b69ca45530610c500b99e 100644
--- a/drivers/pci/endpoint/functions/pci-epf-mhi.c
+++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c
@@ -328,12 +328,6 @@ static int pci_epf_mhi_edma_read(struct mhi_ep_cntrl *mhi_cntrl,
 	config.direction = DMA_DEV_TO_MEM;
 	config.src_addr = buf_info->host_addr;
 
-	ret = dmaengine_slave_config(chan, &config);
-	if (ret) {
-		dev_err(dev, "Failed to configure DMA channel\n");
-		goto err_unlock;
-	}
-
 	dst_addr = dma_map_single(dma_dev, buf_info->dev_addr, buf_info->size,
 				  DMA_FROM_DEVICE);
 	ret = dma_mapping_error(dma_dev, dst_addr);
@@ -342,9 +336,10 @@ static int pci_epf_mhi_edma_read(struct mhi_ep_cntrl *mhi_cntrl,
 		goto err_unlock;
 	}
 
-	desc = dmaengine_prep_slave_single(chan, dst_addr, buf_info->size,
-					   DMA_DEV_TO_MEM,
-					   DMA_CTRL_ACK | DMA_PREP_INTERRUPT);
+	desc = dmaengine_prep_config_single(chan, dst_addr, buf_info->size,
+					    DMA_DEV_TO_MEM,
+					    DMA_CTRL_ACK | DMA_PREP_INTERRUPT,
+					    &config);
 	if (!desc) {
 		dev_err(dev, "Failed to prepare DMA\n");
 		ret = -EIO;
@@ -401,12 +396,6 @@ static int pci_epf_mhi_edma_write(struct mhi_ep_cntrl *mhi_cntrl,
 	config.direction = DMA_MEM_TO_DEV;
 	config.dst_addr = buf_info->host_addr;
 
-	ret = dmaengine_slave_config(chan, &config);
-	if (ret) {
-		dev_err(dev, "Failed to configure DMA channel\n");
-		goto err_unlock;
-	}
-
 	src_addr = dma_map_single(dma_dev, buf_info->dev_addr, buf_info->size,
 				  DMA_TO_DEVICE);
 	ret = dma_mapping_error(dma_dev, src_addr);
@@ -415,9 +404,10 @@ static int pci_epf_mhi_edma_write(struct mhi_ep_cntrl *mhi_cntrl,
 		goto err_unlock;
 	}
 
-	desc = dmaengine_prep_slave_single(chan, src_addr, buf_info->size,
-					   DMA_MEM_TO_DEV,
-					   DMA_CTRL_ACK | DMA_PREP_INTERRUPT);
+	desc = dmaengine_prep_config_single(chan, src_addr, buf_info->size,
+					    DMA_MEM_TO_DEV,
+					    DMA_CTRL_ACK | DMA_PREP_INTERRUPT,
+					    &config);
 	if (!desc) {
 		dev_err(dev, "Failed to prepare DMA\n");
 		ret = -EIO;
@@ -506,12 +496,6 @@ static int pci_epf_mhi_edma_read_async(struct mhi_ep_cntrl *mhi_cntrl,
 	config.direction = DMA_DEV_TO_MEM;
 	config.src_addr = buf_info->host_addr;
 
-	ret = dmaengine_slave_config(chan, &config);
-	if (ret) {
-		dev_err(dev, "Failed to configure DMA channel\n");
-		goto err_unlock;
-	}
-
 	dst_addr = dma_map_single(dma_dev, buf_info->dev_addr, buf_info->size,
 				  DMA_FROM_DEVICE);
 	ret = dma_mapping_error(dma_dev, dst_addr);
@@ -520,9 +504,10 @@ static int pci_epf_mhi_edma_read_async(struct mhi_ep_cntrl *mhi_cntrl,
 		goto err_unlock;
 	}
 
-	desc = dmaengine_prep_slave_single(chan, dst_addr, buf_info->size,
-					   DMA_DEV_TO_MEM,
-					   DMA_CTRL_ACK | DMA_PREP_INTERRUPT);
+	desc = dmaengine_prep_config_single(chan, dst_addr, buf_info->size,
+					    DMA_DEV_TO_MEM,
+					    DMA_CTRL_ACK | DMA_PREP_INTERRUPT,
+					    &config);
 	if (!desc) {
 		dev_err(dev, "Failed to prepare DMA\n");
 		ret = -EIO;
@@ -585,12 +570,6 @@ static int pci_epf_mhi_edma_write_async(struct mhi_ep_cntrl *mhi_cntrl,
 	config.direction = DMA_MEM_TO_DEV;
 	config.dst_addr = buf_info->host_addr;
 
-	ret = dmaengine_slave_config(chan, &config);
-	if (ret) {
-		dev_err(dev, "Failed to configure DMA channel\n");
-		goto err_unlock;
-	}
-
 	src_addr = dma_map_single(dma_dev, buf_info->dev_addr, buf_info->size,
 				  DMA_TO_DEVICE);
 	ret = dma_mapping_error(dma_dev, src_addr);
@@ -599,9 +578,10 @@ static int pci_epf_mhi_edma_write_async(struct mhi_ep_cntrl *mhi_cntrl,
 		goto err_unlock;
 	}
 
-	desc = dmaengine_prep_slave_single(chan, src_addr, buf_info->size,
-					   DMA_MEM_TO_DEV,
-					   DMA_CTRL_ACK | DMA_PREP_INTERRUPT);
+	desc = dmaengine_prep_config_single(chan, src_addr, buf_info->size,
+					    DMA_MEM_TO_DEV,
+					    DMA_CTRL_ACK | DMA_PREP_INTERRUPT,
+					    &config);
 	if (!desc) {
 		dev_err(dev, "Failed to prepare DMA\n");
 		ret = -EIO;

-- 
2.43.0