[linux-2.6-block.git] / drivers / net / mhi_net.c

// SPDX-License-Identifier: GPL-2.0-or-later
/* MHI Network driver - Network over MHI bus
 *
 * Copyright (C) 2020 Linaro Ltd <loic.poulain@linaro.org>
 */

#include <linux/if_arp.h>
#include <linux/mhi.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/u64_stats_sync.h>

#define MHI_NET_MIN_MTU		ETH_MIN_MTU
#define MHI_NET_MAX_MTU		0xffff
#define MHI_NET_DEFAULT_MTU	0x4000

struct mhi_net_stats {
	u64_stats_t rx_packets;
	u64_stats_t rx_bytes;
	u64_stats_t rx_errors;
	u64_stats_t rx_dropped;
	u64_stats_t tx_packets;
	u64_stats_t tx_bytes;
	u64_stats_t tx_errors;
	u64_stats_t tx_dropped;
	struct u64_stats_sync tx_syncp;
	struct u64_stats_sync rx_syncp;
};

struct mhi_net_dev {
	struct mhi_device *mdev;
	struct net_device *ndev;
	struct delayed_work rx_refill;
	struct mhi_net_stats stats;
	u32 rx_queue_sz;
};

static int mhi_ndo_open(struct net_device *ndev)
{
	struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);

	/* Feed the rx buffer pool */
	schedule_delayed_work(&mhi_netdev->rx_refill, 0);

	/* Carrier is established via out-of-band channel (e.g. qmi) */
	netif_carrier_on(ndev);

	netif_start_queue(ndev);

	return 0;
}

static int mhi_ndo_stop(struct net_device *ndev)
{
	struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);

	netif_stop_queue(ndev);
	netif_carrier_off(ndev);
	cancel_delayed_work_sync(&mhi_netdev->rx_refill);

	return 0;
}

static int mhi_ndo_xmit(struct sk_buff *skb, struct net_device *ndev)
{
	struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
	struct mhi_device *mdev = mhi_netdev->mdev;
	int err;

	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);
	}

	if (mhi_queue_is_full(mdev, DMA_TO_DEVICE))
		netif_stop_queue(ndev);

	return NETDEV_TX_OK;
}

static void mhi_ndo_get_stats64(struct net_device *ndev,
				struct rtnl_link_stats64 *stats)
{
	struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
	unsigned int start;

	do {
		start = u64_stats_fetch_begin_irq(&mhi_netdev->stats.rx_syncp);
		stats->rx_packets = u64_stats_read(&mhi_netdev->stats.rx_packets);
		stats->rx_bytes = u64_stats_read(&mhi_netdev->stats.rx_bytes);
		stats->rx_errors = u64_stats_read(&mhi_netdev->stats.rx_errors);
		stats->rx_dropped = u64_stats_read(&mhi_netdev->stats.rx_dropped);
	} while (u64_stats_fetch_retry_irq(&mhi_netdev->stats.rx_syncp, start));

	do {
		start = u64_stats_fetch_begin_irq(&mhi_netdev->stats.tx_syncp);
		stats->tx_packets = u64_stats_read(&mhi_netdev->stats.tx_packets);
		stats->tx_bytes = u64_stats_read(&mhi_netdev->stats.tx_bytes);
		stats->tx_errors = u64_stats_read(&mhi_netdev->stats.tx_errors);
		stats->tx_dropped = u64_stats_read(&mhi_netdev->stats.tx_dropped);
	} while (u64_stats_fetch_retry_irq(&mhi_netdev->stats.tx_syncp, start));
}

static const struct net_device_ops mhi_netdev_ops = {
	.ndo_open               = mhi_ndo_open,
	.ndo_stop               = mhi_ndo_stop,
	.ndo_start_xmit         = mhi_ndo_xmit,
	.ndo_get_stats64	= mhi_ndo_get_stats64,
};

static void mhi_net_setup(struct net_device *ndev)
{
	ndev->header_ops = NULL;  /* No header */
	ndev->type = ARPHRD_RAWIP;
	ndev->hard_header_len = 0;
	ndev->addr_len = 0;
	ndev->flags = IFF_POINTOPOINT | IFF_NOARP;
	ndev->netdev_ops = &mhi_netdev_ops;
	ndev->mtu = MHI_NET_DEFAULT_MTU;
	ndev->min_mtu = MHI_NET_MIN_MTU;
	ndev->max_mtu = MHI_NET_MAX_MTU;
	ndev->tx_queue_len = 1000;
}

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);
	struct sk_buff *skb = mhi_res->buf_addr;
	int free_desc_count;

	free_desc_count = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE);

	if (unlikely(mhi_res->transaction_status)) {
		dev_kfree_skb_any(skb);

		/* MHI layer stopping/resetting the DL channel */
		if (mhi_res->transaction_status == -ENOTCONN)
			return;

		u64_stats_update_begin(&mhi_netdev->stats.rx_syncp);
		u64_stats_inc(&mhi_netdev->stats.rx_errors);
		u64_stats_update_end(&mhi_netdev->stats.rx_syncp);
	} else {
		u64_stats_update_begin(&mhi_netdev->stats.rx_syncp);
		u64_stats_inc(&mhi_netdev->stats.rx_packets);
		u64_stats_add(&mhi_netdev->stats.rx_bytes, mhi_res->bytes_xferd);
		u64_stats_update_end(&mhi_netdev->stats.rx_syncp);

		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;
		}

		skb_put(skb, mhi_res->bytes_xferd);
		netif_rx(skb);
	}

	/* Refill if RX buffers queue becomes low */
	if (free_desc_count >= mhi_netdev->rx_queue_sz / 2)
		schedule_delayed_work(&mhi_netdev->rx_refill, 0);
}

static void mhi_net_ul_callback(struct mhi_device *mhi_dev,
				struct mhi_result *mhi_res)
{
	struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
	struct net_device *ndev = mhi_netdev->ndev;
	struct mhi_device *mdev = mhi_netdev->mdev;
	struct sk_buff *skb = mhi_res->buf_addr;

	/* Hardware has consumed the buffer, so free the skb (which is not
	 * freed by the MHI stack) and perform accounting.
	 */
	dev_consume_skb_any(skb);

	u64_stats_update_begin(&mhi_netdev->stats.tx_syncp);
	if (unlikely(mhi_res->transaction_status)) {

		/* MHI layer stopping/resetting the UL channel */
		if (mhi_res->transaction_status == -ENOTCONN) {
			u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
			return;
		}

		u64_stats_inc(&mhi_netdev->stats.tx_errors);
	} else {
		u64_stats_inc(&mhi_netdev->stats.tx_packets);
		u64_stats_add(&mhi_netdev->stats.tx_bytes, mhi_res->bytes_xferd);
	}
	u64_stats_update_end(&mhi_netdev->stats.tx_syncp);

	if (netif_queue_stopped(ndev) && !mhi_queue_is_full(mdev, DMA_TO_DEVICE))
		netif_wake_queue(ndev);
}

static void mhi_net_rx_refill_work(struct work_struct *work)
{
	struct mhi_net_dev *mhi_netdev = container_of(work, struct mhi_net_dev,
						      rx_refill.work);
	struct net_device *ndev = mhi_netdev->ndev;
	struct mhi_device *mdev = mhi_netdev->mdev;
	int size = READ_ONCE(ndev->mtu);
	struct sk_buff *skb;
	int err;

	while (!mhi_queue_is_full(mdev, DMA_FROM_DEVICE)) {
		skb = netdev_alloc_skb(ndev, size);
		if (unlikely(!skb))
			break;

		err = mhi_queue_skb(mdev, DMA_FROM_DEVICE, skb, size, MHI_EOT);
		if (unlikely(err)) {
			net_err_ratelimited("%s: Failed to queue RX buf (%d)\n",
					    ndev->name, err);
			kfree_skb(skb);
			break;
		}

		/* Do not hog the CPU if rx buffers are consumed faster than
		 * queued (unlikely).
		 */
		cond_resched();
	}

	/* If we're still starved of rx buffers, reschedule later */
	if (mhi_get_free_desc_count(mdev, DMA_FROM_DEVICE) == mhi_netdev->rx_queue_sz)
		schedule_delayed_work(&mhi_netdev->rx_refill, HZ / 2);
}

static struct device_type wwan_type = {
	.name = "wwan",
};

static int mhi_net_probe(struct mhi_device *mhi_dev,
			 const struct mhi_device_id *id)
{
	const char *netname = (char *)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);
	if (!ndev)
		return -ENOMEM;

	mhi_netdev = netdev_priv(ndev);
	dev_set_drvdata(dev, mhi_netdev);
	mhi_netdev->ndev = ndev;
	mhi_netdev->mdev = mhi_dev;
	SET_NETDEV_DEV(ndev, &mhi_dev->dev);
	SET_NETDEV_DEVTYPE(ndev, &wwan_type);

	INIT_DELAYED_WORK(&mhi_netdev->rx_refill, mhi_net_rx_refill_work);
	u64_stats_init(&mhi_netdev->stats.rx_syncp);
	u64_stats_init(&mhi_netdev->stats.tx_syncp);

	/* Start MHI channels */
	err = mhi_prepare_for_transfer(mhi_dev);
	if (err)
		goto out_err;

	/* Number of transfer descriptors determines size of the queue */
	mhi_netdev->rx_queue_sz = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE);

	err = register_netdev(ndev);
	if (err)
		goto out_err;

	return 0;

out_err:
	free_netdev(ndev);
	return err;
}

static void mhi_net_remove(struct mhi_device *mhi_dev)
{
	struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);

	unregister_netdev(mhi_netdev->ndev);

	mhi_unprepare_from_transfer(mhi_netdev->mdev);

	free_netdev(mhi_netdev->ndev);
}

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" },
	{}
};
MODULE_DEVICE_TABLE(mhi, mhi_net_id_table);

static struct mhi_driver mhi_net_driver = {
	.probe = mhi_net_probe,
	.remove = mhi_net_remove,
	.dl_xfer_cb = mhi_net_dl_callback,
	.ul_xfer_cb = mhi_net_ul_callback,
	.id_table = mhi_net_id_table,
	.driver = {
		.name = "mhi_net",
		.owner = THIS_MODULE,
	},
};

module_mhi_driver(mhi_net_driver);

MODULE_AUTHOR("Loic Poulain <loic.poulain@linaro.org>");
MODULE_DESCRIPTION("Network over MHI");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
3ffec6a1 LP	1	// SPDX-License-Identifier: GPL-2.0-or-later
	2	/* MHI Network driver - Network over MHI bus
	3	*
	4	* Copyright (C) 2020 Linaro Ltd <loic.poulain@linaro.org>
	5	*/
	6
	7	#include <linux/if_arp.h>
	8	#include <linux/mhi.h>
	9	#include <linux/mod_devicetable.h>
	10	#include <linux/module.h>
	11	#include <linux/netdevice.h>
	12	#include <linux/skbuff.h>
	13	#include <linux/u64_stats_sync.h>
	14
	15	#define MHI_NET_MIN_MTU ETH_MIN_MTU
	16	#define MHI_NET_MAX_MTU 0xffff
	17	#define MHI_NET_DEFAULT_MTU 0x4000
	18
	19	struct mhi_net_stats {
	20	u64_stats_t rx_packets;
	21	u64_stats_t rx_bytes;
	22	u64_stats_t rx_errors;
	23	u64_stats_t rx_dropped;
	24	u64_stats_t tx_packets;
	25	u64_stats_t tx_bytes;
	26	u64_stats_t tx_errors;
	27	u64_stats_t tx_dropped;
3ffec6a1 LP	28	struct u64_stats_sync tx_syncp;
	29	struct u64_stats_sync rx_syncp;
	30	};
	31
	32	struct mhi_net_dev {
	33	struct mhi_device *mdev;
	34	struct net_device *ndev;
	35	struct delayed_work rx_refill;
	36	struct mhi_net_stats stats;
	37	u32 rx_queue_sz;
	38	};
	39
	40	static int mhi_ndo_open(struct net_device *ndev)
	41	{
	42	struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
	43
	44	/* Feed the rx buffer pool */
	45	schedule_delayed_work(&mhi_netdev->rx_refill, 0);
	46
	47	/* Carrier is established via out-of-band channel (e.g. qmi) */
	48	netif_carrier_on(ndev);
	49
	50	netif_start_queue(ndev);
	51
	52	return 0;
	53	}
	54
	55	static int mhi_ndo_stop(struct net_device *ndev)
	56	{
	57	struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
	58
	59	netif_stop_queue(ndev);
	60	netif_carrier_off(ndev);
	61	cancel_delayed_work_sync(&mhi_netdev->rx_refill);
	62
	63	return 0;
	64	}
	65
	66	static int mhi_ndo_xmit(struct sk_buff skb, struct net_device ndev)
	67	{
	68	struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
	69	struct mhi_device *mdev = mhi_netdev->mdev;
	70	int err;
	71
	72	err = mhi_queue_skb(mdev, DMA_TO_DEVICE, skb, skb->len, MHI_EOT);
	73	if (unlikely(err)) {
	74	net_err_ratelimited("%s: Failed to queue TX buf (%d)\n",
	75	ndev->name, err);
	76
	77	u64_stats_update_begin(&mhi_netdev->stats.tx_syncp);
	78	u64_stats_inc(&mhi_netdev->stats.tx_dropped);
	79	u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
	80
	81	/* drop the packet */
	82	dev_kfree_skb_any(skb);
	83	}
	84
	85	if (mhi_queue_is_full(mdev, DMA_TO_DEVICE))
	86	netif_stop_queue(ndev);
	87
	88	return NETDEV_TX_OK;
	89	}
	90
	91	static void mhi_ndo_get_stats64(struct net_device *ndev,
92	struct rtnl_link_stats64 *stats)
93	{
94	struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
95	unsigned int start;
96
97	do {
98	start = u64_stats_fetch_begin_irq(&mhi_netdev->stats.rx_syncp);
99	stats->rx_packets = u64_stats_read(&mhi_netdev->stats.rx_packets);
100	stats->rx_bytes = u64_stats_read(&mhi_netdev->stats.rx_bytes);
101	stats->rx_errors = u64_stats_read(&mhi_netdev->stats.rx_errors);
102	stats->rx_dropped = u64_stats_read(&mhi_netdev->stats.rx_dropped);
103	} while (u64_stats_fetch_retry_irq(&mhi_netdev->stats.rx_syncp, start));
104
105	do {
106	start = u64_stats_fetch_begin_irq(&mhi_netdev->stats.tx_syncp);
107	stats->tx_packets = u64_stats_read(&mhi_netdev->stats.tx_packets);
108	stats->tx_bytes = u64_stats_read(&mhi_netdev->stats.tx_bytes);
109	stats->tx_errors = u64_stats_read(&mhi_netdev->stats.tx_errors);
110	stats->tx_dropped = u64_stats_read(&mhi_netdev->stats.tx_dropped);
111	} while (u64_stats_fetch_retry_irq(&mhi_netdev->stats.tx_syncp, start));
112	}
113
114	static const struct net_device_ops mhi_netdev_ops = {
115	.ndo_open = mhi_ndo_open,
116	.ndo_stop = mhi_ndo_stop,
117	.ndo_start_xmit = mhi_ndo_xmit,
118	.ndo_get_stats64 = mhi_ndo_get_stats64,
119	};
120
121	static void mhi_net_setup(struct net_device *ndev)
122	{
123	ndev->header_ops = NULL; /* No header */
c134db89	124	ndev->type = ARPHRD_RAWIP;
3ffec6a1 LP	125	ndev->hard_header_len = 0;
	126	ndev->addr_len = 0;
	127	ndev->flags = IFF_POINTOPOINT \| IFF_NOARP;
	128	ndev->netdev_ops = &mhi_netdev_ops;
	129	ndev->mtu = MHI_NET_DEFAULT_MTU;
	130	ndev->min_mtu = MHI_NET_MIN_MTU;
	131	ndev->max_mtu = MHI_NET_MAX_MTU;
	132	ndev->tx_queue_len = 1000;
	133	}
	134
	135	static void mhi_net_dl_callback(struct mhi_device *mhi_dev,
	136	struct mhi_result *mhi_res)
	137	{
	138	struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
	139	struct sk_buff *skb = mhi_res->buf_addr;
6e10785e	140	int free_desc_count;
3ffec6a1	141
6e10785e	142	free_desc_count = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE);
3ffec6a1 LP	143
	144	if (unlikely(mhi_res->transaction_status)) {
	145	dev_kfree_skb_any(skb);
	146
	147	/* MHI layer stopping/resetting the DL channel */
	148	if (mhi_res->transaction_status == -ENOTCONN)
	149	return;
	150
	151	u64_stats_update_begin(&mhi_netdev->stats.rx_syncp);
	152	u64_stats_inc(&mhi_netdev->stats.rx_errors);
	153	u64_stats_update_end(&mhi_netdev->stats.rx_syncp);
	154	} else {
	155	u64_stats_update_begin(&mhi_netdev->stats.rx_syncp);
	156	u64_stats_inc(&mhi_netdev->stats.rx_packets);
	157	u64_stats_add(&mhi_netdev->stats.rx_bytes, mhi_res->bytes_xferd);
	158	u64_stats_update_end(&mhi_netdev->stats.rx_syncp);
	159
c134db89 LP	160	switch (skb->data[0] & 0xf0) {
	161	case 0x40:
	162	skb->protocol = htons(ETH_P_IP);
	163	break;
	164	case 0x60:
	165	skb->protocol = htons(ETH_P_IPV6);
	166	break;
	167	default:
	168	skb->protocol = htons(ETH_P_MAP);
	169	break;
	170	}
	171
3ffec6a1 LP	172	skb_put(skb, mhi_res->bytes_xferd);
	173	netif_rx(skb);
	174	}
	175
	176	/* Refill if RX buffers queue becomes low */
6e10785e	177	if (free_desc_count >= mhi_netdev->rx_queue_sz / 2)
3ffec6a1 LP	178	schedule_delayed_work(&mhi_netdev->rx_refill, 0);
	179	}
	180
	181	static void mhi_net_ul_callback(struct mhi_device *mhi_dev,
	182	struct mhi_result *mhi_res)
	183	{
	184	struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
	185	struct net_device *ndev = mhi_netdev->ndev;
efc36d3c	186	struct mhi_device *mdev = mhi_netdev->mdev;
3ffec6a1 LP	187	struct sk_buff *skb = mhi_res->buf_addr;
	188
	189	/* Hardware has consumed the buffer, so free the skb (which is not
	190	* freed by the MHI stack) and perform accounting.
	191	*/
	192	dev_consume_skb_any(skb);
	193
	194	u64_stats_update_begin(&mhi_netdev->stats.tx_syncp);
	195	if (unlikely(mhi_res->transaction_status)) {
	196
	197	/* MHI layer stopping/resetting the UL channel */
	198	if (mhi_res->transaction_status == -ENOTCONN) {
	199	u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
	200	return;
	201	}
	202
	203	u64_stats_inc(&mhi_netdev->stats.tx_errors);
	204	} else {
	205	u64_stats_inc(&mhi_netdev->stats.tx_packets);
	206	u64_stats_add(&mhi_netdev->stats.tx_bytes, mhi_res->bytes_xferd);
	207	}
	208	u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
	209
efc36d3c	210	if (netif_queue_stopped(ndev) && !mhi_queue_is_full(mdev, DMA_TO_DEVICE))
3ffec6a1 LP	211	netif_wake_queue(ndev);
	212	}
	213
	214	static void mhi_net_rx_refill_work(struct work_struct *work)
	215	{
	216	struct mhi_net_dev *mhi_netdev = container_of(work, struct mhi_net_dev,
	217	rx_refill.work);
	218	struct net_device *ndev = mhi_netdev->ndev;
	219	struct mhi_device *mdev = mhi_netdev->mdev;
	220	int size = READ_ONCE(ndev->mtu);
	221	struct sk_buff *skb;
	222	int err;
	223
6e10785e	224	while (!mhi_queue_is_full(mdev, DMA_FROM_DEVICE)) {
3ffec6a1 LP	225	skb = netdev_alloc_skb(ndev, size);
	226	if (unlikely(!skb))
	227	break;
	228
	229	err = mhi_queue_skb(mdev, DMA_FROM_DEVICE, skb, size, MHI_EOT);
	230	if (unlikely(err)) {
	231	net_err_ratelimited("%s: Failed to queue RX buf (%d)\n",
	232	ndev->name, err);
	233	kfree_skb(skb);
	234	break;
	235	}
	236
3ffec6a1 LP	237	/* Do not hog the CPU if rx buffers are consumed faster than
	238	* queued (unlikely).
	239	*/
	240	cond_resched();
	241	}
	242
	243	/* If we're still starved of rx buffers, reschedule later */
6e10785e	244	if (mhi_get_free_desc_count(mdev, DMA_FROM_DEVICE) == mhi_netdev->rx_queue_sz)
3ffec6a1 LP	245	schedule_delayed_work(&mhi_netdev->rx_refill, HZ / 2);
	246	}
	247
b80b5dbf LP	248	static struct device_type wwan_type = {
	249	.name = "wwan",
	250	};
	251
3ffec6a1 LP	252	static int mhi_net_probe(struct mhi_device *mhi_dev,
	253	const struct mhi_device_id *id)
	254	{
	255	const char netname = (char )id->driver_data;
	256	struct device *dev = &mhi_dev->dev;
	257	struct mhi_net_dev *mhi_netdev;
	258	struct net_device *ndev;
	259	int err;
	260
	261	ndev = alloc_netdev(sizeof(*mhi_netdev), netname, NET_NAME_PREDICTABLE,
	262	mhi_net_setup);
	263	if (!ndev)
	264	return -ENOMEM;
	265
	266	mhi_netdev = netdev_priv(ndev);
	267	dev_set_drvdata(dev, mhi_netdev);
	268	mhi_netdev->ndev = ndev;
	269	mhi_netdev->mdev = mhi_dev;
	270	SET_NETDEV_DEV(ndev, &mhi_dev->dev);
b80b5dbf	271	SET_NETDEV_DEVTYPE(ndev, &wwan_type);
3ffec6a1	272
3ffec6a1 LP	273	INIT_DELAYED_WORK(&mhi_netdev->rx_refill, mhi_net_rx_refill_work);
	274	u64_stats_init(&mhi_netdev->stats.rx_syncp);
	275	u64_stats_init(&mhi_netdev->stats.tx_syncp);
	276
	277	/* Start MHI channels */
	278	err = mhi_prepare_for_transfer(mhi_dev);
	279	if (err)
	280	goto out_err;
	281
e6ec3ccd LP	282	/* Number of transfer descriptors determines size of the queue */
	283	mhi_netdev->rx_queue_sz = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE);
	284
3ffec6a1 LP	285	err = register_netdev(ndev);
	286	if (err)
	287	goto out_err;
	288
	289	return 0;
	290
	291	out_err:
	292	free_netdev(ndev);
	293	return err;
	294	}
	295
	296	static void mhi_net_remove(struct mhi_device *mhi_dev)
	297	{
	298	struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
	299
	300	unregister_netdev(mhi_netdev->ndev);
	301
	302	mhi_unprepare_from_transfer(mhi_netdev->mdev);
	303
	304	free_netdev(mhi_netdev->ndev);
	305	}
	306
	307	static const struct mhi_device_id mhi_net_id_table[] = {
	308	{ .chan = "IP_HW0", .driver_data = (kernel_ulong_t)"mhi_hwip%d" },
	309	{ .chan = "IP_SW0", .driver_data = (kernel_ulong_t)"mhi_swip%d" },
	310	{}
	311	};
	312	MODULE_DEVICE_TABLE(mhi, mhi_net_id_table);
	313
	314	static struct mhi_driver mhi_net_driver = {
	315	.probe = mhi_net_probe,
	316	.remove = mhi_net_remove,
	317	.dl_xfer_cb = mhi_net_dl_callback,
	318	.ul_xfer_cb = mhi_net_ul_callback,
	319	.id_table = mhi_net_id_table,
	320	.driver = {
	321	.name = "mhi_net",
	322	.owner = THIS_MODULE,
	323	},
	324	};
	325
	326	module_mhi_driver(mhi_net_driver);
	327
	328	MODULE_AUTHOR("Loic Poulain <loic.poulain@linaro.org>");
	329	MODULE_DESCRIPTION("Network over MHI");
	330	MODULE_LICENSE("GPL v2");