Re: [PATCH V1] net: mhi : Add support to enable ethernet interface

[Vivek Pernamitta <quic_vpernami@quicinc.com>]

On 6/30/2023 3:14 PM, Vivek Pernamitta wrote:
> Add support to enable ethernet interface for MHI SWIP channels.
>
> Signed-off-by: Vivek Pernamitta <quic_vpernami@quicinc.com>
> ---
>   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..0a47e15 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_random_addr(ndev->dev_addr);
> +		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[] = {