wcn36xx: use dma_zalloc_coherent instead of allocator/memset

Use dma_zalloc_coherent instead of dma_alloc_coherent
followed by memset 0.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ath/wcn36xx/dxe.c

@@ -174,13 +174,12 @@ static int wcn36xx_dxe_init_descs(struct device *dev, struct wcn36xx_dxe_ch *wcn
 	int i;
 
 	size = wcn_ch->desc_num * sizeof(struct wcn36xx_dxe_desc);
-	wcn_ch->cpu_addr = dma_alloc_coherent(dev, size, &wcn_ch->dma_addr,
-					      GFP_KERNEL);
+	wcn_ch->cpu_addr = dma_zalloc_coherent(dev, size,
+					       &wcn_ch->dma_addr,
+					       GFP_KERNEL);
 	if (!wcn_ch->cpu_addr)
 		return -ENOMEM;
 
-	memset(wcn_ch->cpu_addr, 0, size);
-
 	cur_dxe = (struct wcn36xx_dxe_desc *)wcn_ch->cpu_addr;
 	cur_ctl = wcn_ch->head_blk_ctl;
 
@@ -628,13 +627,13 @@ int wcn36xx_dxe_allocate_mem_pools(struct wcn36xx *wcn)
 		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
 
 	s = wcn->mgmt_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_H;
-	cpu_addr = dma_alloc_coherent(wcn->dev, s, &wcn->mgmt_mem_pool.phy_addr,
-				      GFP_KERNEL);
+	cpu_addr = dma_zalloc_coherent(wcn->dev, s,
+				       &wcn->mgmt_mem_pool.phy_addr,
+				       GFP_KERNEL);
 	if (!cpu_addr)
 		goto out_err;
 
 	wcn->mgmt_mem_pool.virt_addr = cpu_addr;
-	memset(cpu_addr, 0, s);
 
 	/* Allocate BD headers for DATA frames */
 
@@ -643,13 +642,13 @@ int wcn36xx_dxe_allocate_mem_pools(struct wcn36xx *wcn)
 		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
 
 	s = wcn->data_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_L;
-	cpu_addr = dma_alloc_coherent(wcn->dev, s, &wcn->data_mem_pool.phy_addr,
-				      GFP_KERNEL);
+	cpu_addr = dma_zalloc_coherent(wcn->dev, s,
+				       &wcn->data_mem_pool.phy_addr,
+				       GFP_KERNEL);
 	if (!cpu_addr)
 		goto out_err;
 
 	wcn->data_mem_pool.virt_addr = cpu_addr;
-	memset(cpu_addr, 0, s);
 
 	return 0;