Commit ddeb9bfa authored by Loic Poulain's avatar Loic Poulain Committed by David S. Miller
Browse files

net: mhi: Add protocol support 



MHI can transport different protocols, some are handled at upper level,
like IP and QMAP(rmnet/netlink), but others will need to be inside MHI
net driver, like mbim. This change adds support for protocol rx and
tx_fixup callbacks registration, that can be used to encode/decode the
targeted protocol.

Signed-off-by: default avatarLoic Poulain <loic.poulain@linaro.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 24a1720a

drivers/net/mhi_net.c

+57 −12
Original line number Diff line number Diff line
@@ -34,11 +34,24 @@ struct mhi_net_dev { 
	struct net_device *ndev;

	struct sk_buff *skbagg_head;

	struct sk_buff *skbagg_tail;

	const struct mhi_net_proto *proto;

	void *proto_data;

	struct delayed_work rx_refill;

	struct mhi_net_stats stats;

	u32 rx_queue_sz;

};



struct mhi_net_proto {

	int (*init)(struct mhi_net_dev *mhi_netdev);

	struct sk_buff * (*tx_fixup)(struct mhi_net_dev *mhi_netdev, struct sk_buff *skb);

	void (*rx)(struct mhi_net_dev *mhi_netdev, struct sk_buff *skb);

};



struct mhi_device_info {

	const char *netname;

	const struct mhi_net_proto *proto;

};



static int mhi_ndo_open(struct net_device *ndev)

{

	struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
@@ -68,26 +81,35 @@ static int mhi_ndo_stop(struct net_device *ndev) 
static int mhi_ndo_xmit(struct sk_buff *skb, struct net_device *ndev)

{

	struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);

	const struct mhi_net_proto *proto = mhi_netdev->proto;

	struct mhi_device *mdev = mhi_netdev->mdev;

	int err;



	if (proto && proto->tx_fixup) {

		skb = proto->tx_fixup(mhi_netdev, skb);

		if (unlikely(!skb))

			goto exit_drop;

	}



	err = mhi_queue_skb(mdev, DMA_TO_DEVICE, skb, skb->len, MHI_EOT);

	if (unlikely(err)) {

		net_err_ratelimited("%s: Failed to queue TX buf (%d)\n",

				    ndev->name, err);



		u64_stats_update_begin(&mhi_netdev->stats.tx_syncp);

		u64_stats_inc(&mhi_netdev->stats.tx_dropped);

		u64_stats_update_end(&mhi_netdev->stats.tx_syncp);



		/* drop the packet */

		dev_kfree_skb_any(skb);

		goto exit_drop;

	}



	if (mhi_queue_is_full(mdev, DMA_TO_DEVICE))

		netif_stop_queue(ndev);



	return NETDEV_TX_OK;



exit_drop:

	u64_stats_update_begin(&mhi_netdev->stats.tx_syncp);

	u64_stats_inc(&mhi_netdev->stats.tx_dropped);

	u64_stats_update_end(&mhi_netdev->stats.tx_syncp);



	return NETDEV_TX_OK;

}



static void mhi_ndo_get_stats64(struct net_device *ndev,
@@ -164,6 +186,7 @@ static void mhi_net_dl_callback(struct mhi_device *mhi_dev, 
				struct mhi_result *mhi_res)

{

	struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);

	const struct mhi_net_proto *proto = mhi_netdev->proto;

	struct sk_buff *skb = mhi_res->buf_addr;

	int free_desc_count;
@@ -220,6 +243,9 @@ static void mhi_net_dl_callback(struct mhi_device *mhi_dev, 
			break;

		}



		if (proto && proto->rx)

			proto->rx(mhi_netdev, skb);

		else

			netif_rx(skb);

	}
@@ -302,14 +328,14 @@ static struct device_type wwan_type = { 
static int mhi_net_probe(struct mhi_device *mhi_dev,

			 const struct mhi_device_id *id)

{

	const char *netname = (char *)id->driver_data;

	const struct mhi_device_info *info = (struct mhi_device_info *)id->driver_data;

	struct device *dev = &mhi_dev->dev;

	struct mhi_net_dev *mhi_netdev;

	struct net_device *ndev;

	int err;



	ndev = alloc_netdev(sizeof(*mhi_netdev), netname, NET_NAME_PREDICTABLE,

			    mhi_net_setup);

	ndev = alloc_netdev(sizeof(*mhi_netdev), info->netname,

			    NET_NAME_PREDICTABLE, mhi_net_setup);

	if (!ndev)

		return -ENOMEM;
@@ -318,6 +344,7 @@ static int mhi_net_probe(struct mhi_device *mhi_dev, 
	mhi_netdev->ndev = ndev;

	mhi_netdev->mdev = mhi_dev;

	mhi_netdev->skbagg_head = NULL;

	mhi_netdev->proto = info->proto;

	SET_NETDEV_DEV(ndev, &mhi_dev->dev);

	SET_NETDEV_DEVTYPE(ndev, &wwan_type);
@@ -337,8 +364,16 @@ static int mhi_net_probe(struct mhi_device *mhi_dev, 
	if (err)

		goto out_err;



	if (mhi_netdev->proto) {

		err = mhi_netdev->proto->init(mhi_netdev);

		if (err)

			goto out_err_proto;

	}



	return 0;



out_err_proto:

	unregister_netdev(ndev);

out_err:

	free_netdev(ndev);

	return err;
@@ -358,9 +393,19 @@ static void mhi_net_remove(struct mhi_device *mhi_dev) 
	free_netdev(mhi_netdev->ndev);

}



static const struct mhi_device_info mhi_hwip0 = {

	.netname = "mhi_hwip%d",

};



static const struct mhi_device_info mhi_swip0 = {

	.netname = "mhi_swip%d",

};



static const struct mhi_device_id mhi_net_id_table[] = {

	{ .chan = "IP_HW0", .driver_data = (kernel_ulong_t)"mhi_hwip%d" },

	{ .chan = "IP_SW0", .driver_data = (kernel_ulong_t)"mhi_swip%d" },

	/* Hardware accelerated data PATH (to modem IPA), protocol agnostic */

	{ .chan = "IP_HW0", .driver_data = (kernel_ulong_t)&mhi_hwip0 },

	/* Software data PATH (to modem CPU) */

	{ .chan = "IP_SW0", .driver_data = (kernel_ulong_t)&mhi_swip0 },

	{}

};

MODULE_DEVICE_TABLE(mhi, mhi_net_id_table);