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From:   Vivek Pernamitta <quic_vpernami@quicinc.com>
To:     mhi@lists.linux.dev
Cc:     mrana@quicinc.com, quic_qianyu@quicinc.com,
        manivannan.sadhasivam@linaro.org, quic_vbadigan@quicinc.com,
        quic_krichai@quicinc.com, quic_skananth@quicinc.com,
        linux-arm-msm@vger.kernel.org,
        Vivek Pernamitta <quic_vpernami@quicinc.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        netdev@vger.kernel.org (open list:NETWORKING DRIVERS),
        linux-kernel@vger.kernel.org (open list)
Subject: [PATCH V2] net: mhi : Add support to enable ethernet interface
Date:   Tue, 18 Jul 2023 11:45:28 +0530
Message-Id: <1689660928-12092-1-git-send-email-quic_vpernami@quicinc.com>
Precedence: bulk

Add support to enable ethernet interface for MHI SWIP channels.

Signed-off-by: Vivek Pernamitta <quic_vpernami@quicinc.com>
Reviewed-by: Daniele Palmas <dnlplm@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
---

changes since v1:
	- Moved to net-next from linux-next	
	- moved to eth_hw_addr_random() to assign Ethernet MAC address
	  from eth_random_addr()
---
 drivers/net/mhi_net.c | 53 ++++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 40 insertions(+), 13 deletions(-)

diff --git a/drivers/net/mhi_net.c b/drivers/net/mhi_net.c
index 3d322ac..5bb8d99 100644
--- a/drivers/net/mhi_net.c
+++ b/drivers/net/mhi_net.c
@@ -11,6 +11,7 @@
 #include <linux/netdevice.h>
 #include <linux/skbuff.h>
 #include <linux/u64_stats_sync.h>
+#include <linux/etherdevice.h>
 
 #define MHI_NET_MIN_MTU		ETH_MIN_MTU
 #define MHI_NET_MAX_MTU		0xffff
@@ -38,10 +39,12 @@ struct mhi_net_dev {
 	u32 rx_queue_sz;
 	int msg_enable;
 	unsigned int mru;
+	bool ethernet_if;
 };
 
 struct mhi_device_info {
 	const char *netname;
+	bool ethernet_if;
 };
 
 static int mhi_ndo_open(struct net_device *ndev)
@@ -140,6 +143,14 @@ static void mhi_net_setup(struct net_device *ndev)
 	ndev->tx_queue_len = 1000;
 }
 
+static void mhi_ethernet_setup(struct net_device *ndev)
+{
+	ndev->netdev_ops = &mhi_netdev_ops;
+	ether_setup(ndev);
+	ndev->min_mtu = ETH_MIN_MTU;
+	ndev->max_mtu = ETH_MAX_MTU;
+}
+
 static struct sk_buff *mhi_net_skb_agg(struct mhi_net_dev *mhi_netdev,
 				       struct sk_buff *skb)
 {
@@ -209,16 +220,22 @@ static void mhi_net_dl_callback(struct mhi_device *mhi_dev,
 			mhi_netdev->skbagg_head = NULL;
 		}
 
-		switch (skb->data[0] & 0xf0) {
-		case 0x40:
-			skb->protocol = htons(ETH_P_IP);
-			break;
-		case 0x60:
-			skb->protocol = htons(ETH_P_IPV6);
-			break;
-		default:
-			skb->protocol = htons(ETH_P_MAP);
-			break;
+		if (mhi_netdev->ethernet_if) {
+			skb_copy_to_linear_data(skb, skb->data,
+						mhi_res->bytes_xferd);
+			skb->protocol = eth_type_trans(skb, mhi_netdev->ndev);
+		} else {
+			switch (skb->data[0] & 0xf0) {
+			case 0x40:
+				skb->protocol = htons(ETH_P_IP);
+				break;
+			case 0x60:
+				skb->protocol = htons(ETH_P_IPV6);
+				break;
+			default:
+				skb->protocol = htons(ETH_P_MAP);
+				break;
+			}
 		}
 
 		u64_stats_update_begin(&mhi_netdev->stats.rx_syncp);
@@ -301,11 +318,17 @@ static void mhi_net_rx_refill_work(struct work_struct *work)
 		schedule_delayed_work(&mhi_netdev->rx_refill, HZ / 2);
 }
 
-static int mhi_net_newlink(struct mhi_device *mhi_dev, struct net_device *ndev)
+static int mhi_net_newlink(struct mhi_device *mhi_dev, struct net_device *ndev, bool eth_dev)
 {
 	struct mhi_net_dev *mhi_netdev;
 	int err;
 
+	if (eth_dev) {
+		eth_hw_addr_random(ndev);
+		if (!is_valid_ether_addr(ndev->dev_addr))
+			return -EADDRNOTAVAIL;
+	}
+
 	mhi_netdev = netdev_priv(ndev);
 
 	dev_set_drvdata(&mhi_dev->dev, mhi_netdev);
@@ -313,6 +336,7 @@ static int mhi_net_newlink(struct mhi_device *mhi_dev, struct net_device *ndev)
 	mhi_netdev->mdev = mhi_dev;
 	mhi_netdev->skbagg_head = NULL;
 	mhi_netdev->mru = mhi_dev->mhi_cntrl->mru;
+	mhi_netdev->ethernet_if = eth_dev;
 
 	INIT_DELAYED_WORK(&mhi_netdev->rx_refill, mhi_net_rx_refill_work);
 	u64_stats_init(&mhi_netdev->stats.rx_syncp);
@@ -356,13 +380,14 @@ static int mhi_net_probe(struct mhi_device *mhi_dev,
 	int err;
 
 	ndev = alloc_netdev(sizeof(struct mhi_net_dev), info->netname,
-			    NET_NAME_PREDICTABLE, mhi_net_setup);
+			    NET_NAME_PREDICTABLE, info->ethernet_if ?
+			    mhi_ethernet_setup : mhi_net_setup);
 	if (!ndev)
 		return -ENOMEM;
 
 	SET_NETDEV_DEV(ndev, &mhi_dev->dev);
 
-	err = mhi_net_newlink(mhi_dev, ndev);
+	err = mhi_net_newlink(mhi_dev, ndev, info->ethernet_if);
 	if (err) {
 		free_netdev(ndev);
 		return err;
@@ -380,10 +405,12 @@ static void mhi_net_remove(struct mhi_device *mhi_dev)
 
 static const struct mhi_device_info mhi_hwip0 = {
 	.netname = "mhi_hwip%d",
+	.ethernet_if = false,
 };
 
 static const struct mhi_device_info mhi_swip0 = {
 	.netname = "mhi_swip%d",
+	.ethernet_if = false,
 };
 
 static const struct mhi_device_id mhi_net_id_table[] = {
-- 
2.7.4