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  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/* MHI MBIM Network driver - Network/MBIM over MHI bus
  3 *
  4 * Copyright (C) 2021 Linaro Ltd <loic.poulain@linaro.org>
  5 *
  6 * This driver copy some code from cdc_ncm, which is:
  7 * Copyright (C) ST-Ericsson 2010-2012
  8 * and cdc_mbim, which is:
  9 * Copyright (c) 2012  Smith Micro Software, Inc.
 10 * Copyright (c) 2012  Bjørn Mork <bjorn@mork.no>
 11 *
 12 */
 13
 14#include <linux/ethtool.h>
 15#include <linux/if_arp.h>
 16#include <linux/if_vlan.h>
 17#include <linux/ip.h>
 18#include <linux/mhi.h>
 19#include <linux/mii.h>
 20#include <linux/mod_devicetable.h>
 21#include <linux/module.h>
 22#include <linux/netdevice.h>
 23#include <linux/skbuff.h>
 24#include <linux/u64_stats_sync.h>
 25#include <linux/usb.h>
 26#include <linux/usb/cdc.h>
 27#include <linux/usb/usbnet.h>
 28#include <linux/usb/cdc_ncm.h>
 29#include <linux/wwan.h>
 30
 31/* 3500 allows to optimize skb allocation, the skbs will basically fit in
 32 * one 4K page. Large MBIM packets will simply be split over several MHI
 33 * transfers and chained by the MHI net layer (zerocopy).
 34 */
 35#define MHI_DEFAULT_MRU 3500
 36
 37#define MHI_MBIM_DEFAULT_MTU 1500
 38#define MHI_MAX_BUF_SZ 0xffff
 39
 40#define MBIM_NDP16_SIGN_MASK 0x00ffffff
 41
 42#define MHI_MBIM_LINK_HASH_SIZE 8
 43#define LINK_HASH(session) ((session) % MHI_MBIM_LINK_HASH_SIZE)
 44
 45struct mhi_mbim_link {
 46	struct mhi_mbim_context *mbim;
 47	struct net_device *ndev;
 48	unsigned int session;
 49
 50	/* stats */
 51	u64_stats_t rx_packets;
 52	u64_stats_t rx_bytes;
 53	u64_stats_t rx_errors;
 54	u64_stats_t tx_packets;
 55	u64_stats_t tx_bytes;
 56	u64_stats_t tx_errors;
 57	u64_stats_t tx_dropped;
 58	struct u64_stats_sync tx_syncp;
 59	struct u64_stats_sync rx_syncp;
 60
 61	struct hlist_node hlnode;
 62};
 63
 64struct mhi_mbim_context {
 65	struct mhi_device *mdev;
 66	struct sk_buff *skbagg_head;
 67	struct sk_buff *skbagg_tail;
 68	unsigned int mru;
 69	u32 rx_queue_sz;
 70	u16 rx_seq;
 71	u16 tx_seq;
 72	struct delayed_work rx_refill;
 73	spinlock_t tx_lock;
 74	struct hlist_head link_list[MHI_MBIM_LINK_HASH_SIZE];
 75};
 76
 77struct mbim_tx_hdr {
 78	struct usb_cdc_ncm_nth16 nth16;
 79	struct usb_cdc_ncm_ndp16 ndp16;
 80	struct usb_cdc_ncm_dpe16 dpe16[2];
 81} __packed;
 82
 83static struct mhi_mbim_link *mhi_mbim_get_link_rcu(struct mhi_mbim_context *mbim,
 84						   unsigned int session)
 85{
 86	struct mhi_mbim_link *link;
 87
 88	hlist_for_each_entry_rcu(link, &mbim->link_list[LINK_HASH(session)], hlnode) {
 89		if (link->session == session)
 90			return link;
 91	}
 92
 93	return NULL;
 94}
 95
 96static struct sk_buff *mbim_tx_fixup(struct sk_buff *skb, unsigned int session,
 97				     u16 tx_seq)
 98{
 99	unsigned int dgram_size = skb->len;
100	struct usb_cdc_ncm_nth16 *nth16;
101	struct usb_cdc_ncm_ndp16 *ndp16;
102	struct mbim_tx_hdr *mbim_hdr;
103
104	/* Only one NDP is sent, containing the IP packet (no aggregation) */
105
106	/* Ensure we have enough headroom for crafting MBIM header */
107	if (skb_cow_head(skb, sizeof(struct mbim_tx_hdr))) {
108		dev_kfree_skb_any(skb);
109		return NULL;
110	}
111
112	mbim_hdr = skb_push(skb, sizeof(struct mbim_tx_hdr));
113
114	/* Fill NTB header */
115	nth16 = &mbim_hdr->nth16;
116	nth16->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
117	nth16->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
118	nth16->wSequence = cpu_to_le16(tx_seq);
119	nth16->wBlockLength = cpu_to_le16(skb->len);
120	nth16->wNdpIndex = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
121
122	/* Fill the unique NDP */
123	ndp16 = &mbim_hdr->ndp16;
124	ndp16->dwSignature = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN | (session << 24));
125	ndp16->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp16)
126					+ sizeof(struct usb_cdc_ncm_dpe16) * 2);
127	ndp16->wNextNdpIndex = 0;
128
129	/* Datagram follows the mbim header */
130	ndp16->dpe16[0].wDatagramIndex = cpu_to_le16(sizeof(struct mbim_tx_hdr));
131	ndp16->dpe16[0].wDatagramLength = cpu_to_le16(dgram_size);
132
133	/* null termination */
134	ndp16->dpe16[1].wDatagramIndex = 0;
135	ndp16->dpe16[1].wDatagramLength = 0;
136
137	return skb;
138}
139
140static netdev_tx_t mhi_mbim_ndo_xmit(struct sk_buff *skb, struct net_device *ndev)
141{
142	struct mhi_mbim_link *link = wwan_netdev_drvpriv(ndev);
143	struct mhi_mbim_context *mbim = link->mbim;
144	unsigned long flags;
145	int err = -ENOMEM;
146
147	/* Serialize MHI channel queuing and MBIM seq */
148	spin_lock_irqsave(&mbim->tx_lock, flags);
149
150	skb = mbim_tx_fixup(skb, link->session, mbim->tx_seq);
151	if (unlikely(!skb))
152		goto exit_unlock;
153
154	err = mhi_queue_skb(mbim->mdev, DMA_TO_DEVICE, skb, skb->len, MHI_EOT);
155
156	if (mhi_queue_is_full(mbim->mdev, DMA_TO_DEVICE))
157		netif_stop_queue(ndev);
158
159	if (!err)
160		mbim->tx_seq++;
161
162exit_unlock:
163	spin_unlock_irqrestore(&mbim->tx_lock, flags);
164
165	if (unlikely(err)) {
166		net_err_ratelimited("%s: Failed to queue TX buf (%d)\n",
167				    ndev->name, err);
168		dev_kfree_skb_any(skb);
169		goto exit_drop;
170	}
171
172	return NETDEV_TX_OK;
173
174exit_drop:
175	u64_stats_update_begin(&link->tx_syncp);
176	u64_stats_inc(&link->tx_dropped);
177	u64_stats_update_end(&link->tx_syncp);
178
179	return NETDEV_TX_OK;
180}
181
182static int mbim_rx_verify_nth16(struct mhi_mbim_context *mbim, struct sk_buff *skb)
183{
184	struct usb_cdc_ncm_nth16 *nth16;
185	int len;
186
187	if (skb->len < sizeof(struct usb_cdc_ncm_nth16) +
188			sizeof(struct usb_cdc_ncm_ndp16)) {
189		net_err_ratelimited("frame too short\n");
190		return -EINVAL;
191	}
192
193	nth16 = (struct usb_cdc_ncm_nth16 *)skb->data;
194
195	if (nth16->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN)) {
196		net_err_ratelimited("invalid NTH16 signature <%#010x>\n",
197				    le32_to_cpu(nth16->dwSignature));
198		return -EINVAL;
199	}
200
201	/* No limit on the block length, except the size of the data pkt */
202	len = le16_to_cpu(nth16->wBlockLength);
203	if (len > skb->len) {
204		net_err_ratelimited("NTB does not fit into the skb %u/%u\n",
205				    len, skb->len);
206		return -EINVAL;
207	}
208
209	if (mbim->rx_seq + 1 != le16_to_cpu(nth16->wSequence) &&
210	    (mbim->rx_seq || le16_to_cpu(nth16->wSequence)) &&
211	    !(mbim->rx_seq == 0xffff && !le16_to_cpu(nth16->wSequence))) {
212		net_err_ratelimited("sequence number glitch prev=%d curr=%d\n",
213				    mbim->rx_seq, le16_to_cpu(nth16->wSequence));
214	}
215	mbim->rx_seq = le16_to_cpu(nth16->wSequence);
216
217	return le16_to_cpu(nth16->wNdpIndex);
218}
219
220static int mbim_rx_verify_ndp16(struct sk_buff *skb, struct usb_cdc_ncm_ndp16 *ndp16)
221{
222	int ret;
223
224	if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) {
225		net_err_ratelimited("invalid DPT16 length <%u>\n",
226				    le16_to_cpu(ndp16->wLength));
227		return -EINVAL;
228	}
229
230	ret = ((le16_to_cpu(ndp16->wLength) - sizeof(struct usb_cdc_ncm_ndp16))
231			/ sizeof(struct usb_cdc_ncm_dpe16));
232	ret--; /* Last entry is always a NULL terminator */
233
234	if (sizeof(struct usb_cdc_ncm_ndp16) +
235	     ret * sizeof(struct usb_cdc_ncm_dpe16) > skb->len) {
236		net_err_ratelimited("Invalid nframes = %d\n", ret);
237		return -EINVAL;
238	}
239
240	return ret;
241}
242
243static void mhi_mbim_rx(struct mhi_mbim_context *mbim, struct sk_buff *skb)
244{
245	int ndpoffset;
246
247	/* Check NTB header and retrieve first NDP offset */
248	ndpoffset = mbim_rx_verify_nth16(mbim, skb);
249	if (ndpoffset < 0) {
250		net_err_ratelimited("mbim: Incorrect NTB header\n");
251		goto error;
252	}
253
254	/* Process each NDP */
255	while (1) {
256		struct usb_cdc_ncm_ndp16 ndp16;
257		struct usb_cdc_ncm_dpe16 dpe16;
258		struct mhi_mbim_link *link;
259		int nframes, n, dpeoffset;
260		unsigned int session;
261
262		if (skb_copy_bits(skb, ndpoffset, &ndp16, sizeof(ndp16))) {
263			net_err_ratelimited("mbim: Incorrect NDP offset (%u)\n",
264					    ndpoffset);
265			goto error;
266		}
267
268		/* Check NDP header and retrieve number of datagrams */
269		nframes = mbim_rx_verify_ndp16(skb, &ndp16);
270		if (nframes < 0) {
271			net_err_ratelimited("mbim: Incorrect NDP16\n");
272			goto error;
273		}
274
275		 /* Only IP data type supported, no DSS in MHI context */
276		if ((ndp16.dwSignature & cpu_to_le32(MBIM_NDP16_SIGN_MASK))
277				!= cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN)) {
278			net_err_ratelimited("mbim: Unsupported NDP type\n");
279			goto next_ndp;
280		}
281
282		session = (le32_to_cpu(ndp16.dwSignature) & ~MBIM_NDP16_SIGN_MASK) >> 24;
283
284		rcu_read_lock();
285
286		link = mhi_mbim_get_link_rcu(mbim, session);
287		if (!link) {
288			net_err_ratelimited("mbim: bad packet session (%u)\n", session);
289			goto unlock;
290		}
291
292		/* de-aggregate and deliver IP packets */
293		dpeoffset = ndpoffset + sizeof(struct usb_cdc_ncm_ndp16);
294		for (n = 0; n < nframes; n++, dpeoffset += sizeof(dpe16)) {
295			u16 dgram_offset, dgram_len;
296			struct sk_buff *skbn;
297
298			if (skb_copy_bits(skb, dpeoffset, &dpe16, sizeof(dpe16)))
299				break;
300
301			dgram_offset = le16_to_cpu(dpe16.wDatagramIndex);
302			dgram_len = le16_to_cpu(dpe16.wDatagramLength);
303
304			if (!dgram_offset || !dgram_len)
305				break; /* null terminator */
306
307			skbn = netdev_alloc_skb(link->ndev, dgram_len);
308			if (!skbn)
309				continue;
310
311			skb_put(skbn, dgram_len);
312			skb_copy_bits(skb, dgram_offset, skbn->data, dgram_len);
313
314			switch (skbn->data[0] & 0xf0) {
315			case 0x40:
316				skbn->protocol = htons(ETH_P_IP);
317				break;
318			case 0x60:
319				skbn->protocol = htons(ETH_P_IPV6);
320				break;
321			default:
322				net_err_ratelimited("%s: unknown protocol\n",
323						    link->ndev->name);
324				dev_kfree_skb_any(skbn);
325				u64_stats_update_begin(&link->rx_syncp);
326				u64_stats_inc(&link->rx_errors);
327				u64_stats_update_end(&link->rx_syncp);
328				continue;
329			}
330
331			u64_stats_update_begin(&link->rx_syncp);
332			u64_stats_inc(&link->rx_packets);
333			u64_stats_add(&link->rx_bytes, skbn->len);
334			u64_stats_update_end(&link->rx_syncp);
335
336			netif_rx(skbn);
337		}
338unlock:
339		rcu_read_unlock();
340next_ndp:
341		/* Other NDP to process? */
342		ndpoffset = (int)le16_to_cpu(ndp16.wNextNdpIndex);
343		if (!ndpoffset)
344			break;
345	}
346
347	/* free skb */
348	dev_consume_skb_any(skb);
349	return;
350error:
351	dev_kfree_skb_any(skb);
352}
353
354static struct sk_buff *mhi_net_skb_agg(struct mhi_mbim_context *mbim,
355				       struct sk_buff *skb)
356{
357	struct sk_buff *head = mbim->skbagg_head;
358	struct sk_buff *tail = mbim->skbagg_tail;
359
360	/* This is non-paged skb chaining using frag_list */
361	if (!head) {
362		mbim->skbagg_head = skb;
363		return skb;
364	}
365
366	if (!skb_shinfo(head)->frag_list)
367		skb_shinfo(head)->frag_list = skb;
368	else
369		tail->next = skb;
370
371	head->len += skb->len;
372	head->data_len += skb->len;
373	head->truesize += skb->truesize;
374
375	mbim->skbagg_tail = skb;
376
377	return mbim->skbagg_head;
378}
379
380static void mhi_net_rx_refill_work(struct work_struct *work)
381{
382	struct mhi_mbim_context *mbim = container_of(work, struct mhi_mbim_context,
383						     rx_refill.work);
384	struct mhi_device *mdev = mbim->mdev;
385	int err;
386
387	while (!mhi_queue_is_full(mdev, DMA_FROM_DEVICE)) {
388		struct sk_buff *skb = alloc_skb(mbim->mru, GFP_KERNEL);
389
390		if (unlikely(!skb))
391			break;
392
393		err = mhi_queue_skb(mdev, DMA_FROM_DEVICE, skb,
394				    mbim->mru, MHI_EOT);
395		if (unlikely(err)) {
396			kfree_skb(skb);
397			break;
398		}
399
400		/* Do not hog the CPU if rx buffers are consumed faster than
401		 * queued (unlikely).
402		 */
403		cond_resched();
404	}
405
406	/* If we're still starved of rx buffers, reschedule later */
407	if (mhi_get_free_desc_count(mdev, DMA_FROM_DEVICE) == mbim->rx_queue_sz)
408		schedule_delayed_work(&mbim->rx_refill, HZ / 2);
409}
410
411static void mhi_mbim_dl_callback(struct mhi_device *mhi_dev,
412				 struct mhi_result *mhi_res)
413{
414	struct mhi_mbim_context *mbim = dev_get_drvdata(&mhi_dev->dev);
415	struct sk_buff *skb = mhi_res->buf_addr;
416	int free_desc_count;
417
418	free_desc_count = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE);
419
420	if (unlikely(mhi_res->transaction_status)) {
421		switch (mhi_res->transaction_status) {
422		case -EOVERFLOW:
423			/* Packet has been split over multiple transfers */
424			skb_put(skb, mhi_res->bytes_xferd);
425			mhi_net_skb_agg(mbim, skb);
426			break;
427		case -ENOTCONN:
428			/* MHI layer stopping/resetting the DL channel */
429			dev_kfree_skb_any(skb);
430			return;
431		default:
432			/* Unknown error, simply drop */
433			dev_kfree_skb_any(skb);
434		}
435	} else {
436		skb_put(skb, mhi_res->bytes_xferd);
437
438		if (mbim->skbagg_head) {
439			/* Aggregate the final fragment */
440			skb = mhi_net_skb_agg(mbim, skb);
441			mbim->skbagg_head = NULL;
442		}
443
444		mhi_mbim_rx(mbim, skb);
445	}
446
447	/* Refill if RX buffers queue becomes low */
448	if (free_desc_count >= mbim->rx_queue_sz / 2)
449		schedule_delayed_work(&mbim->rx_refill, 0);
450}
451
452static void mhi_mbim_ndo_get_stats64(struct net_device *ndev,
453				     struct rtnl_link_stats64 *stats)
454{
455	struct mhi_mbim_link *link = wwan_netdev_drvpriv(ndev);
456	unsigned int start;
457
458	do {
459		start = u64_stats_fetch_begin(&link->rx_syncp);
460		stats->rx_packets = u64_stats_read(&link->rx_packets);
461		stats->rx_bytes = u64_stats_read(&link->rx_bytes);
462		stats->rx_errors = u64_stats_read(&link->rx_errors);
463	} while (u64_stats_fetch_retry(&link->rx_syncp, start));
464
465	do {
466		start = u64_stats_fetch_begin(&link->tx_syncp);
467		stats->tx_packets = u64_stats_read(&link->tx_packets);
468		stats->tx_bytes = u64_stats_read(&link->tx_bytes);
469		stats->tx_errors = u64_stats_read(&link->tx_errors);
470		stats->tx_dropped = u64_stats_read(&link->tx_dropped);
471	} while (u64_stats_fetch_retry(&link->tx_syncp, start));
472}
473
474static void mhi_mbim_ul_callback(struct mhi_device *mhi_dev,
475				 struct mhi_result *mhi_res)
476{
477	struct mhi_mbim_context *mbim = dev_get_drvdata(&mhi_dev->dev);
478	struct sk_buff *skb = mhi_res->buf_addr;
479	struct net_device *ndev = skb->dev;
480	struct mhi_mbim_link *link = wwan_netdev_drvpriv(ndev);
481
482	/* Hardware has consumed the buffer, so free the skb (which is not
483	 * freed by the MHI stack) and perform accounting.
484	 */
485	dev_consume_skb_any(skb);
486
487	u64_stats_update_begin(&link->tx_syncp);
488	if (unlikely(mhi_res->transaction_status)) {
489		/* MHI layer stopping/resetting the UL channel */
490		if (mhi_res->transaction_status == -ENOTCONN) {
491			u64_stats_update_end(&link->tx_syncp);
492			return;
493		}
494
495		u64_stats_inc(&link->tx_errors);
496	} else {
497		u64_stats_inc(&link->tx_packets);
498		u64_stats_add(&link->tx_bytes, mhi_res->bytes_xferd);
499	}
500	u64_stats_update_end(&link->tx_syncp);
501
502	if (netif_queue_stopped(ndev) && !mhi_queue_is_full(mbim->mdev, DMA_TO_DEVICE))
503		netif_wake_queue(ndev);
504}
505
506static int mhi_mbim_ndo_open(struct net_device *ndev)
507{
508	struct mhi_mbim_link *link = wwan_netdev_drvpriv(ndev);
509
510	/* Feed the MHI rx buffer pool */
511	schedule_delayed_work(&link->mbim->rx_refill, 0);
512
513	/* Carrier is established via out-of-band channel (e.g. qmi) */
514	netif_carrier_on(ndev);
515
516	netif_start_queue(ndev);
517
518	return 0;
519}
520
521static int mhi_mbim_ndo_stop(struct net_device *ndev)
522{
523	netif_stop_queue(ndev);
524	netif_carrier_off(ndev);
525
526	return 0;
527}
528
529static const struct net_device_ops mhi_mbim_ndo = {
530	.ndo_open = mhi_mbim_ndo_open,
531	.ndo_stop = mhi_mbim_ndo_stop,
532	.ndo_start_xmit = mhi_mbim_ndo_xmit,
533	.ndo_get_stats64 = mhi_mbim_ndo_get_stats64,
534};
535
536static int mhi_mbim_newlink(void *ctxt, struct net_device *ndev, u32 if_id,
537			    struct netlink_ext_ack *extack)
538{
539	struct mhi_mbim_link *link = wwan_netdev_drvpriv(ndev);
540	struct mhi_mbim_context *mbim = ctxt;
541
542	link->session = if_id;
543	link->mbim = mbim;
544	link->ndev = ndev;
545	u64_stats_init(&link->rx_syncp);
546	u64_stats_init(&link->tx_syncp);
547
548	rcu_read_lock();
549	if (mhi_mbim_get_link_rcu(mbim, if_id)) {
550		rcu_read_unlock();
551		return -EEXIST;
552	}
553	rcu_read_unlock();
554
555	/* Already protected by RTNL lock */
556	hlist_add_head_rcu(&link->hlnode, &mbim->link_list[LINK_HASH(if_id)]);
557
558	return register_netdevice(ndev);
559}
560
561static void mhi_mbim_dellink(void *ctxt, struct net_device *ndev,
562			     struct list_head *head)
563{
564	struct mhi_mbim_link *link = wwan_netdev_drvpriv(ndev);
565
566	hlist_del_init_rcu(&link->hlnode);
567	synchronize_rcu();
568
569	unregister_netdevice_queue(ndev, head);
570}
571
572static void mhi_mbim_setup(struct net_device *ndev)
573{
574	ndev->header_ops = NULL;  /* No header */
575	ndev->type = ARPHRD_RAWIP;
576	ndev->needed_headroom = sizeof(struct mbim_tx_hdr);
577	ndev->hard_header_len = 0;
578	ndev->addr_len = 0;
579	ndev->flags = IFF_POINTOPOINT | IFF_NOARP;
580	ndev->netdev_ops = &mhi_mbim_ndo;
581	ndev->mtu = MHI_MBIM_DEFAULT_MTU;
582	ndev->min_mtu = ETH_MIN_MTU;
583	ndev->max_mtu = MHI_MAX_BUF_SZ - ndev->needed_headroom;
584	ndev->tx_queue_len = 1000;
585	ndev->needs_free_netdev = true;
586}
587
588static const struct wwan_ops mhi_mbim_wwan_ops = {
589	.priv_size = sizeof(struct mhi_mbim_link),
590	.setup = mhi_mbim_setup,
591	.newlink = mhi_mbim_newlink,
592	.dellink = mhi_mbim_dellink,
593};
594
595static int mhi_mbim_probe(struct mhi_device *mhi_dev, const struct mhi_device_id *id)
596{
597	struct mhi_controller *cntrl = mhi_dev->mhi_cntrl;
598	struct mhi_mbim_context *mbim;
599	int err;
600
601	mbim = devm_kzalloc(&mhi_dev->dev, sizeof(*mbim), GFP_KERNEL);
602	if (!mbim)
603		return -ENOMEM;
604
605	spin_lock_init(&mbim->tx_lock);
606	dev_set_drvdata(&mhi_dev->dev, mbim);
607	mbim->mdev = mhi_dev;
608	mbim->mru = mhi_dev->mhi_cntrl->mru ? mhi_dev->mhi_cntrl->mru : MHI_DEFAULT_MRU;
609
610	INIT_DELAYED_WORK(&mbim->rx_refill, mhi_net_rx_refill_work);
611
612	/* Start MHI channels */
613	err = mhi_prepare_for_transfer(mhi_dev);
614	if (err)
615		return err;
616
617	/* Number of transfer descriptors determines size of the queue */
618	mbim->rx_queue_sz = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE);
619
620	/* Register wwan link ops with MHI controller representing WWAN instance */
621	return wwan_register_ops(&cntrl->mhi_dev->dev, &mhi_mbim_wwan_ops, mbim, 0);
622}
623
624static void mhi_mbim_remove(struct mhi_device *mhi_dev)
625{
626	struct mhi_mbim_context *mbim = dev_get_drvdata(&mhi_dev->dev);
627	struct mhi_controller *cntrl = mhi_dev->mhi_cntrl;
628
629	mhi_unprepare_from_transfer(mhi_dev);
630	cancel_delayed_work_sync(&mbim->rx_refill);
631	wwan_unregister_ops(&cntrl->mhi_dev->dev);
632	kfree_skb(mbim->skbagg_head);
633	dev_set_drvdata(&mhi_dev->dev, NULL);
634}
635
636static const struct mhi_device_id mhi_mbim_id_table[] = {
637	/* Hardware accelerated data PATH (to modem IPA), MBIM protocol */
638	{ .chan = "IP_HW0_MBIM", .driver_data = 0 },
639	{}
640};
641MODULE_DEVICE_TABLE(mhi, mhi_mbim_id_table);
642
643static struct mhi_driver mhi_mbim_driver = {
644	.probe = mhi_mbim_probe,
645	.remove = mhi_mbim_remove,
646	.dl_xfer_cb = mhi_mbim_dl_callback,
647	.ul_xfer_cb = mhi_mbim_ul_callback,
648	.id_table = mhi_mbim_id_table,
649	.driver = {
650		.name = "mhi_wwan_mbim",
651		.owner = THIS_MODULE,
652	},
653};
654
655module_mhi_driver(mhi_mbim_driver);
656
657MODULE_AUTHOR("Loic Poulain <loic.poulain@linaro.org>");
658MODULE_DESCRIPTION("Network/MBIM over MHI");
659MODULE_LICENSE("GPL v2");