[PATCH] net: moxa: inherit DMA masks to make dma_map_single() work

[Sergei Antonov <saproj@gmail.com>]

dma_map_single() calls fail in moxart_mac_setup_desc_ring() and
moxart_mac_start_xmit() which leads to an incessant output of this:

[   16.043925] moxart-ethernet 92000000.mac eth0: DMA mapping error
[   16.050957] moxart-ethernet 92000000.mac eth0: DMA mapping error
[   16.058229] moxart-ethernet 92000000.mac eth0: DMA mapping error

To make dma_map_single() work, inherit DMA masks from the platform device.

Signed-off-by: Sergei Antonov <saproj@gmail.com>
CC: Jakub Kicinski <kuba@kernel.org>
CC: Pavel Skripkin <paskripkin@gmail.com>
CC: David S. Miller <davem@davemloft.net>
CC: Guobin Huang <huangguobin4@huawei.com>
CC: Paolo Abeni <pabeni@redhat.com>
---
 drivers/net/ethernet/moxa/moxart_ether.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/moxa/moxart_ether.c b/drivers/net/ethernet/moxa/moxart_ether.c
index a3214a762e4b..de99211d85c2 100644
--- a/drivers/net/ethernet/moxa/moxart_ether.c
+++ b/drivers/net/ethernet/moxa/moxart_ether.c
@@ -537,6 +537,10 @@ static int moxart_mac_probe(struct platform_device *pdev)
 	ndev->priv_flags |= IFF_UNICAST_FLT;
 	ndev->irq = irq;
 
+	/* Inherit the DMA masks from the platform device */
+	ndev->dev.dma_mask = p_dev->dma_mask;
+	ndev->dev.coherent_dma_mask = p_dev->coherent_dma_mask;
+
 	SET_NETDEV_DEV(ndev, &pdev->dev);
 
 	ret = register_netdev(ndev);
-- 
2.32.0