1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) ST-Ericsson AB 2010
4 * Author:  Daniel Martensson
5 *	    Dmitry.Tarnyagin  / dmitry.tarnyagin@lockless.no
6 */
7
8#define pr_fmt(fmt) KBUILD_MODNAME fmt
9
10#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/device.h>
13#include <linux/netdevice.h>
14#include <linux/string.h>
15#include <linux/list.h>
16#include <linux/interrupt.h>
17#include <linux/delay.h>
18#include <linux/sched.h>
19#include <linux/if_arp.h>
20#include <linux/timer.h>
21#include <net/rtnetlink.h>
22#include <linux/pkt_sched.h>
23#include <net/caif/caif_layer.h>
24#include <net/caif/caif_hsi.h>
25
26MODULE_LICENSE("GPL");
27MODULE_AUTHOR("Daniel Martensson");
28MODULE_DESCRIPTION("CAIF HSI driver");
29
30/* Returns the number of padding bytes for alignment. */
31#define PAD_POW2(x, pow) ((((x)&((pow)-1)) == 0) ? 0 :\
32				(((pow)-((x)&((pow)-1)))))
33
34static const struct cfhsi_config  hsi_default_config = {
35
36	/* Inactivity timeout on HSI, ms */
37	.inactivity_timeout = HZ,
38
39	/* Aggregation timeout (ms) of zero means no aggregation is done*/
40	.aggregation_timeout = 1,
41
42	/*
43	 * HSI link layer flow-control thresholds.
44	 * Threshold values for the HSI packet queue. Flow-control will be
45	 * asserted when the number of packets exceeds q_high_mark. It will
46	 * not be de-asserted before the number of packets drops below
47	 * q_low_mark.
48	 * Warning: A high threshold value might increase throughput but it
49	 * will at the same time prevent channel prioritization and increase
50	 * the risk of flooding the modem. The high threshold should be above
51	 * the low.
52	 */
53	.q_high_mark = 100,
54	.q_low_mark = 50,
55
56	/*
57	 * HSI padding options.
58	 * Warning: must be a base of 2 (& operation used) and can not be zero !
59	 */
60	.head_align = 4,
61	.tail_align = 4,
62};
63
64#define ON 1
65#define OFF 0
66
67static LIST_HEAD(cfhsi_list);
68
69static void cfhsi_inactivity_tout(struct timer_list *t)
70{
71	struct cfhsi *cfhsi = from_timer(cfhsi, t, inactivity_timer);
72
73	netdev_dbg(cfhsi->ndev, "%s.\n",
74		__func__);
75
76	/* Schedule power down work queue. */
77	if (!test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
78		queue_work(cfhsi->wq, &cfhsi->wake_down_work);
79}
80
81static void cfhsi_update_aggregation_stats(struct cfhsi *cfhsi,
82					   const struct sk_buff *skb,
83					   int direction)
84{
85	struct caif_payload_info *info;
86	int hpad, tpad, len;
87
88	info = (struct caif_payload_info *)&skb->cb;
89	hpad = 1 + PAD_POW2((info->hdr_len + 1), cfhsi->cfg.head_align);
90	tpad = PAD_POW2((skb->len + hpad), cfhsi->cfg.tail_align);
91	len = skb->len + hpad + tpad;
92
93	if (direction > 0)
94		cfhsi->aggregation_len += len;
95	else if (direction < 0)
96		cfhsi->aggregation_len -= len;
97}
98
99static bool cfhsi_can_send_aggregate(struct cfhsi *cfhsi)
100{
101	int i;
102
103	if (cfhsi->cfg.aggregation_timeout == 0)
104		return true;
105
106	for (i = 0; i < CFHSI_PRIO_BEBK; ++i) {
107		if (cfhsi->qhead[i].qlen)
108			return true;
109	}
110
111	/* TODO: Use aggregation_len instead */
112	if (cfhsi->qhead[CFHSI_PRIO_BEBK].qlen >= CFHSI_MAX_PKTS)
113		return true;
114
115	return false;
116}
117
118static struct sk_buff *cfhsi_dequeue(struct cfhsi *cfhsi)
119{
120	struct sk_buff *skb;
121	int i;
122
123	for (i = 0; i < CFHSI_PRIO_LAST; ++i) {
124		skb = skb_dequeue(&cfhsi->qhead[i]);
125		if (skb)
126			break;
127	}
128
129	return skb;
130}
131
132static int cfhsi_tx_queue_len(struct cfhsi *cfhsi)
133{
134	int i, len = 0;
135	for (i = 0; i < CFHSI_PRIO_LAST; ++i)
136		len += skb_queue_len(&cfhsi->qhead[i]);
137	return len;
138}
139
140static void cfhsi_abort_tx(struct cfhsi *cfhsi)
141{
142	struct sk_buff *skb;
143
144	for (;;) {
145		spin_lock_bh(&cfhsi->lock);
146		skb = cfhsi_dequeue(cfhsi);
147		if (!skb)
148			break;
149
150		cfhsi->ndev->stats.tx_errors++;
151		cfhsi->ndev->stats.tx_dropped++;
152		cfhsi_update_aggregation_stats(cfhsi, skb, -1);
153		spin_unlock_bh(&cfhsi->lock);
154		kfree_skb(skb);
155	}
156	cfhsi->tx_state = CFHSI_TX_STATE_IDLE;
157	if (!test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
158		mod_timer(&cfhsi->inactivity_timer,
159			jiffies + cfhsi->cfg.inactivity_timeout);
160	spin_unlock_bh(&cfhsi->lock);
161}
162
163static int cfhsi_flush_fifo(struct cfhsi *cfhsi)
164{
165	char buffer[32]; /* Any reasonable value */
166	size_t fifo_occupancy;
167	int ret;
168
169	netdev_dbg(cfhsi->ndev, "%s.\n",
170		__func__);
171
172	do {
173		ret = cfhsi->ops->cfhsi_fifo_occupancy(cfhsi->ops,
174				&fifo_occupancy);
175		if (ret) {
176			netdev_warn(cfhsi->ndev,
177				"%s: can't get FIFO occupancy: %d.\n",
178				__func__, ret);
179			break;
180		} else if (!fifo_occupancy)
181			/* No more data, exitting normally */
182			break;
183
184		fifo_occupancy = min(sizeof(buffer), fifo_occupancy);
185		set_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits);
186		ret = cfhsi->ops->cfhsi_rx(buffer, fifo_occupancy,
187				cfhsi->ops);
188		if (ret) {
189			clear_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits);
190			netdev_warn(cfhsi->ndev,
191				"%s: can't read data: %d.\n",
192				__func__, ret);
193			break;
194		}
195
196		ret = 5 * HZ;
197		ret = wait_event_interruptible_timeout(cfhsi->flush_fifo_wait,
198			 !test_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits), ret);
199
200		if (ret < 0) {
201			netdev_warn(cfhsi->ndev,
202				"%s: can't wait for flush complete: %d.\n",
203				__func__, ret);
204			break;
205		} else if (!ret) {
206			ret = -ETIMEDOUT;
207			netdev_warn(cfhsi->ndev,
208				"%s: timeout waiting for flush complete.\n",
209				__func__);
210			break;
211		}
212	} while (1);
213
214	return ret;
215}
216
217static int cfhsi_tx_frm(struct cfhsi_desc *desc, struct cfhsi *cfhsi)
218{
219	int nfrms = 0;
220	int pld_len = 0;
221	struct sk_buff *skb;
222	u8 *pfrm = desc->emb_frm + CFHSI_MAX_EMB_FRM_SZ;
223
224	skb = cfhsi_dequeue(cfhsi);
225	if (!skb)
226		return 0;
227
228	/* Clear offset. */
229	desc->offset = 0;
230
231	/* Check if we can embed a CAIF frame. */
232	if (skb->len < CFHSI_MAX_EMB_FRM_SZ) {
233		struct caif_payload_info *info;
234		int hpad;
235		int tpad;
236
237		/* Calculate needed head alignment and tail alignment. */
238		info = (struct caif_payload_info *)&skb->cb;
239
240		hpad = 1 + PAD_POW2((info->hdr_len + 1), cfhsi->cfg.head_align);
241		tpad = PAD_POW2((skb->len + hpad), cfhsi->cfg.tail_align);
242
243		/* Check if frame still fits with added alignment. */
244		if ((skb->len + hpad + tpad) <= CFHSI_MAX_EMB_FRM_SZ) {
245			u8 *pemb = desc->emb_frm;
246			desc->offset = CFHSI_DESC_SHORT_SZ;
247			*pemb = (u8)(hpad - 1);
248			pemb += hpad;
249
250			/* Update network statistics. */
251			spin_lock_bh(&cfhsi->lock);
252			cfhsi->ndev->stats.tx_packets++;
253			cfhsi->ndev->stats.tx_bytes += skb->len;
254			cfhsi_update_aggregation_stats(cfhsi, skb, -1);
255			spin_unlock_bh(&cfhsi->lock);
256
257			/* Copy in embedded CAIF frame. */
258			skb_copy_bits(skb, 0, pemb, skb->len);
259
260			/* Consume the SKB */
261			consume_skb(skb);
262			skb = NULL;
263		}
264	}
265
266	/* Create payload CAIF frames. */
267	while (nfrms < CFHSI_MAX_PKTS) {
268		struct caif_payload_info *info;
269		int hpad;
270		int tpad;
271
272		if (!skb)
273			skb = cfhsi_dequeue(cfhsi);
274
275		if (!skb)
276			break;
277
278		/* Calculate needed head alignment and tail alignment. */
279		info = (struct caif_payload_info *)&skb->cb;
280
281		hpad = 1 + PAD_POW2((info->hdr_len + 1), cfhsi->cfg.head_align);
282		tpad = PAD_POW2((skb->len + hpad), cfhsi->cfg.tail_align);
283
284		/* Fill in CAIF frame length in descriptor. */
285		desc->cffrm_len[nfrms] = hpad + skb->len + tpad;
286
287		/* Fill head padding information. */
288		*pfrm = (u8)(hpad - 1);
289		pfrm += hpad;
290
291		/* Update network statistics. */
292		spin_lock_bh(&cfhsi->lock);
293		cfhsi->ndev->stats.tx_packets++;
294		cfhsi->ndev->stats.tx_bytes += skb->len;
295		cfhsi_update_aggregation_stats(cfhsi, skb, -1);
296		spin_unlock_bh(&cfhsi->lock);
297
298		/* Copy in CAIF frame. */
299		skb_copy_bits(skb, 0, pfrm, skb->len);
300
301		/* Update payload length. */
302		pld_len += desc->cffrm_len[nfrms];
303
304		/* Update frame pointer. */
305		pfrm += skb->len + tpad;
306
307		/* Consume the SKB */
308		consume_skb(skb);
309		skb = NULL;
310
311		/* Update number of frames. */
312		nfrms++;
313	}
314
315	/* Unused length fields should be zero-filled (according to SPEC). */
316	while (nfrms < CFHSI_MAX_PKTS) {
317		desc->cffrm_len[nfrms] = 0x0000;
318		nfrms++;
319	}
320
321	/* Check if we can piggy-back another descriptor. */
322	if (cfhsi_can_send_aggregate(cfhsi))
323		desc->header |= CFHSI_PIGGY_DESC;
324	else
325		desc->header &= ~CFHSI_PIGGY_DESC;
326
327	return CFHSI_DESC_SZ + pld_len;
328}
329
330static void cfhsi_start_tx(struct cfhsi *cfhsi)
331{
332	struct cfhsi_desc *desc = (struct cfhsi_desc *)cfhsi->tx_buf;
333	int len, res;
334
335	netdev_dbg(cfhsi->ndev, "%s.\n", __func__);
336
337	if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
338		return;
339
340	do {
341		/* Create HSI frame. */
342		len = cfhsi_tx_frm(desc, cfhsi);
343		if (!len) {
344			spin_lock_bh(&cfhsi->lock);
345			if (unlikely(cfhsi_tx_queue_len(cfhsi))) {
346				spin_unlock_bh(&cfhsi->lock);
347				res = -EAGAIN;
348				continue;
349			}
350			cfhsi->tx_state = CFHSI_TX_STATE_IDLE;
351			/* Start inactivity timer. */
352			mod_timer(&cfhsi->inactivity_timer,
353				jiffies + cfhsi->cfg.inactivity_timeout);
354			spin_unlock_bh(&cfhsi->lock);
355			break;
356		}
357
358		/* Set up new transfer. */
359		res = cfhsi->ops->cfhsi_tx(cfhsi->tx_buf, len, cfhsi->ops);
360		if (WARN_ON(res < 0))
361			netdev_err(cfhsi->ndev, "%s: TX error %d.\n",
362				__func__, res);
363	} while (res < 0);
364}
365
366static void cfhsi_tx_done(struct cfhsi *cfhsi)
367{
368	netdev_dbg(cfhsi->ndev, "%s.\n", __func__);
369
370	if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
371		return;
372
373	/*
374	 * Send flow on if flow off has been previously signalled
375	 * and number of packets is below low water mark.
376	 */
377	spin_lock_bh(&cfhsi->lock);
378	if (cfhsi->flow_off_sent &&
379			cfhsi_tx_queue_len(cfhsi) <= cfhsi->cfg.q_low_mark &&
380			cfhsi->cfdev.flowctrl) {
381
382		cfhsi->flow_off_sent = 0;
383		cfhsi->cfdev.flowctrl(cfhsi->ndev, ON);
384	}
385
386	if (cfhsi_can_send_aggregate(cfhsi)) {
387		spin_unlock_bh(&cfhsi->lock);
388		cfhsi_start_tx(cfhsi);
389	} else {
390		mod_timer(&cfhsi->aggregation_timer,
391			jiffies + cfhsi->cfg.aggregation_timeout);
392		spin_unlock_bh(&cfhsi->lock);
393	}
394
395	return;
396}
397
398static void cfhsi_tx_done_cb(struct cfhsi_cb_ops *cb_ops)
399{
400	struct cfhsi *cfhsi;
401
402	cfhsi = container_of(cb_ops, struct cfhsi, cb_ops);
403	netdev_dbg(cfhsi->ndev, "%s.\n",
404		__func__);
405
406	if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
407		return;
408	cfhsi_tx_done(cfhsi);
409}
410
411static int cfhsi_rx_desc(struct cfhsi_desc *desc, struct cfhsi *cfhsi)
412{
413	int xfer_sz = 0;
414	int nfrms = 0;
415	u16 *plen = NULL;
416	u8 *pfrm = NULL;
417
418	if ((desc->header & ~CFHSI_PIGGY_DESC) ||
419			(desc->offset > CFHSI_MAX_EMB_FRM_SZ)) {
420		netdev_err(cfhsi->ndev, "%s: Invalid descriptor.\n",
421			__func__);
422		return -EPROTO;
423	}
424
425	/* Check for embedded CAIF frame. */
426	if (desc->offset) {
427		struct sk_buff *skb;
428		int len = 0;
429		pfrm = ((u8 *)desc) + desc->offset;
430
431		/* Remove offset padding. */
432		pfrm += *pfrm + 1;
433
434		/* Read length of CAIF frame (little endian). */
435		len = *pfrm;
436		len |= ((*(pfrm+1)) << 8) & 0xFF00;
437		len += 2;	/* Add FCS fields. */
438
439		/* Sanity check length of CAIF frame. */
440		if (unlikely(len > CFHSI_MAX_CAIF_FRAME_SZ)) {
441			netdev_err(cfhsi->ndev, "%s: Invalid length.\n",
442				__func__);
443			return -EPROTO;
444		}
445
446		/* Allocate SKB (OK even in IRQ context). */
447		skb = alloc_skb(len + 1, GFP_ATOMIC);
448		if (!skb) {
449			netdev_err(cfhsi->ndev, "%s: Out of memory !\n",
450				__func__);
451			return -ENOMEM;
452		}
453		caif_assert(skb != NULL);
454
455		skb_put_data(skb, pfrm, len);
456
457		skb->protocol = htons(ETH_P_CAIF);
458		skb_reset_mac_header(skb);
459		skb->dev = cfhsi->ndev;
460
461		netif_rx_any_context(skb);
462
463		/* Update network statistics. */
464		cfhsi->ndev->stats.rx_packets++;
465		cfhsi->ndev->stats.rx_bytes += len;
466	}
467
468	/* Calculate transfer length. */
469	plen = desc->cffrm_len;
470	while (nfrms < CFHSI_MAX_PKTS && *plen) {
471		xfer_sz += *plen;
472		plen++;
473		nfrms++;
474	}
475
476	/* Check for piggy-backed descriptor. */
477	if (desc->header & CFHSI_PIGGY_DESC)
478		xfer_sz += CFHSI_DESC_SZ;
479
480	if ((xfer_sz % 4) || (xfer_sz > (CFHSI_BUF_SZ_RX - CFHSI_DESC_SZ))) {
481		netdev_err(cfhsi->ndev,
482				"%s: Invalid payload len: %d, ignored.\n",
483			__func__, xfer_sz);
484		return -EPROTO;
485	}
486	return xfer_sz;
487}
488
489static int cfhsi_rx_desc_len(struct cfhsi_desc *desc)
490{
491	int xfer_sz = 0;
492	int nfrms = 0;
493	u16 *plen;
494
495	if ((desc->header & ~CFHSI_PIGGY_DESC) ||
496			(desc->offset > CFHSI_MAX_EMB_FRM_SZ)) {
497
498		pr_err("Invalid descriptor. %x %x\n", desc->header,
499				desc->offset);
500		return -EPROTO;
501	}
502
503	/* Calculate transfer length. */
504	plen = desc->cffrm_len;
505	while (nfrms < CFHSI_MAX_PKTS && *plen) {
506		xfer_sz += *plen;
507		plen++;
508		nfrms++;
509	}
510
511	if (xfer_sz % 4) {
512		pr_err("Invalid payload len: %d, ignored.\n", xfer_sz);
513		return -EPROTO;
514	}
515	return xfer_sz;
516}
517
518static int cfhsi_rx_pld(struct cfhsi_desc *desc, struct cfhsi *cfhsi)
519{
520	int rx_sz = 0;
521	int nfrms = 0;
522	u16 *plen = NULL;
523	u8 *pfrm = NULL;
524
525	/* Sanity check header and offset. */
526	if (WARN_ON((desc->header & ~CFHSI_PIGGY_DESC) ||
527			(desc->offset > CFHSI_MAX_EMB_FRM_SZ))) {
528		netdev_err(cfhsi->ndev, "%s: Invalid descriptor.\n",
529			__func__);
530		return -EPROTO;
531	}
532
533	/* Set frame pointer to start of payload. */
534	pfrm = desc->emb_frm + CFHSI_MAX_EMB_FRM_SZ;
535	plen = desc->cffrm_len;
536
537	/* Skip already processed frames. */
538	while (nfrms < cfhsi->rx_state.nfrms) {
539		pfrm += *plen;
540		rx_sz += *plen;
541		plen++;
542		nfrms++;
543	}
544
545	/* Parse payload. */
546	while (nfrms < CFHSI_MAX_PKTS && *plen) {
547		struct sk_buff *skb;
548		u8 *pcffrm = NULL;
549		int len;
550
551		/* CAIF frame starts after head padding. */
552		pcffrm = pfrm + *pfrm + 1;
553
554		/* Read length of CAIF frame (little endian). */
555		len = *pcffrm;
556		len |= ((*(pcffrm + 1)) << 8) & 0xFF00;
557		len += 2;	/* Add FCS fields. */
558
559		/* Sanity check length of CAIF frames. */
560		if (unlikely(len > CFHSI_MAX_CAIF_FRAME_SZ)) {
561			netdev_err(cfhsi->ndev, "%s: Invalid length.\n",
562				__func__);
563			return -EPROTO;
564		}
565
566		/* Allocate SKB (OK even in IRQ context). */
567		skb = alloc_skb(len + 1, GFP_ATOMIC);
568		if (!skb) {
569			netdev_err(cfhsi->ndev, "%s: Out of memory !\n",
570				__func__);
571			cfhsi->rx_state.nfrms = nfrms;
572			return -ENOMEM;
573		}
574		caif_assert(skb != NULL);
575
576		skb_put_data(skb, pcffrm, len);
577
578		skb->protocol = htons(ETH_P_CAIF);
579		skb_reset_mac_header(skb);
580		skb->dev = cfhsi->ndev;
581
582		netif_rx_any_context(skb);
583
584		/* Update network statistics. */
585		cfhsi->ndev->stats.rx_packets++;
586		cfhsi->ndev->stats.rx_bytes += len;
587
588		pfrm += *plen;
589		rx_sz += *plen;
590		plen++;
591		nfrms++;
592	}
593
594	return rx_sz;
595}
596
597static void cfhsi_rx_done(struct cfhsi *cfhsi)
598{
599	int res;
600	int desc_pld_len = 0, rx_len, rx_state;
601	struct cfhsi_desc *desc = NULL;
602	u8 *rx_ptr, *rx_buf;
603	struct cfhsi_desc *piggy_desc = NULL;
604
605	desc = (struct cfhsi_desc *)cfhsi->rx_buf;
606
607	netdev_dbg(cfhsi->ndev, "%s\n", __func__);
608
609	if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
610		return;
611
612	/* Update inactivity timer if pending. */
613	spin_lock_bh(&cfhsi->lock);
614	mod_timer_pending(&cfhsi->inactivity_timer,
615			jiffies + cfhsi->cfg.inactivity_timeout);
616	spin_unlock_bh(&cfhsi->lock);
617
618	if (cfhsi->rx_state.state == CFHSI_RX_STATE_DESC) {
619		desc_pld_len = cfhsi_rx_desc_len(desc);
620
621		if (desc_pld_len < 0)
622			goto out_of_sync;
623
624		rx_buf = cfhsi->rx_buf;
625		rx_len = desc_pld_len;
626		if (desc_pld_len > 0 && (desc->header & CFHSI_PIGGY_DESC))
627			rx_len += CFHSI_DESC_SZ;
628		if (desc_pld_len == 0)
629			rx_buf = cfhsi->rx_flip_buf;
630	} else {
631		rx_buf = cfhsi->rx_flip_buf;
632
633		rx_len = CFHSI_DESC_SZ;
634		if (cfhsi->rx_state.pld_len > 0 &&
635				(desc->header & CFHSI_PIGGY_DESC)) {
636
637			piggy_desc = (struct cfhsi_desc *)
638				(desc->emb_frm + CFHSI_MAX_EMB_FRM_SZ +
639						cfhsi->rx_state.pld_len);
640
641			cfhsi->rx_state.piggy_desc = true;
642
643			/* Extract payload len from piggy-backed descriptor. */
644			desc_pld_len = cfhsi_rx_desc_len(piggy_desc);
645			if (desc_pld_len < 0)
646				goto out_of_sync;
647
648			if (desc_pld_len > 0) {
649				rx_len = desc_pld_len;
650				if (piggy_desc->header & CFHSI_PIGGY_DESC)
651					rx_len += CFHSI_DESC_SZ;
652			}
653
654			/*
655			 * Copy needed information from the piggy-backed
656			 * descriptor to the descriptor in the start.
657			 */
658			memcpy(rx_buf, (u8 *)piggy_desc,
659					CFHSI_DESC_SHORT_SZ);
660		}
661	}
662
663	if (desc_pld_len) {
664		rx_state = CFHSI_RX_STATE_PAYLOAD;
665		rx_ptr = rx_buf + CFHSI_DESC_SZ;
666	} else {
667		rx_state = CFHSI_RX_STATE_DESC;
668		rx_ptr = rx_buf;
669		rx_len = CFHSI_DESC_SZ;
670	}
671
672	/* Initiate next read */
673	if (test_bit(CFHSI_AWAKE, &cfhsi->bits)) {
674		/* Set up new transfer. */
675		netdev_dbg(cfhsi->ndev, "%s: Start RX.\n",
676				__func__);
677
678		res = cfhsi->ops->cfhsi_rx(rx_ptr, rx_len,
679				cfhsi->ops);
680		if (WARN_ON(res < 0)) {
681			netdev_err(cfhsi->ndev, "%s: RX error %d.\n",
682				__func__, res);
683			cfhsi->ndev->stats.rx_errors++;
684			cfhsi->ndev->stats.rx_dropped++;
685		}
686	}
687
688	if (cfhsi->rx_state.state == CFHSI_RX_STATE_DESC) {
689		/* Extract payload from descriptor */
690		if (cfhsi_rx_desc(desc, cfhsi) < 0)
691			goto out_of_sync;
692	} else {
693		/* Extract payload */
694		if (cfhsi_rx_pld(desc, cfhsi) < 0)
695			goto out_of_sync;
696		if (piggy_desc) {
697			/* Extract any payload in piggyback descriptor. */
698			if (cfhsi_rx_desc(piggy_desc, cfhsi) < 0)
699				goto out_of_sync;
700			/* Mark no embedded frame after extracting it */
701			piggy_desc->offset = 0;
702		}
703	}
704
705	/* Update state info */
706	memset(&cfhsi->rx_state, 0, sizeof(cfhsi->rx_state));
707	cfhsi->rx_state.state = rx_state;
708	cfhsi->rx_ptr = rx_ptr;
709	cfhsi->rx_len = rx_len;
710	cfhsi->rx_state.pld_len = desc_pld_len;
711	cfhsi->rx_state.piggy_desc = desc->header & CFHSI_PIGGY_DESC;
712
713	if (rx_buf != cfhsi->rx_buf)
714		swap(cfhsi->rx_buf, cfhsi->rx_flip_buf);
715	return;
716
717out_of_sync:
718	netdev_err(cfhsi->ndev, "%s: Out of sync.\n", __func__);
719	print_hex_dump_bytes("--> ", DUMP_PREFIX_NONE,
720			cfhsi->rx_buf, CFHSI_DESC_SZ);
721	schedule_work(&cfhsi->out_of_sync_work);
722}
723
724static void cfhsi_rx_slowpath(struct timer_list *t)
725{
726	struct cfhsi *cfhsi = from_timer(cfhsi, t, rx_slowpath_timer);
727
728	netdev_dbg(cfhsi->ndev, "%s.\n",
729		__func__);
730
731	cfhsi_rx_done(cfhsi);
732}
733
734static void cfhsi_rx_done_cb(struct cfhsi_cb_ops *cb_ops)
735{
736	struct cfhsi *cfhsi;
737
738	cfhsi = container_of(cb_ops, struct cfhsi, cb_ops);
739	netdev_dbg(cfhsi->ndev, "%s.\n",
740		__func__);
741
742	if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
743		return;
744
745	if (test_and_clear_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits))
746		wake_up_interruptible(&cfhsi->flush_fifo_wait);
747	else
748		cfhsi_rx_done(cfhsi);
749}
750
751static void cfhsi_wake_up(struct work_struct *work)
752{
753	struct cfhsi *cfhsi = NULL;
754	int res;
755	int len;
756	long ret;
757
758	cfhsi = container_of(work, struct cfhsi, wake_up_work);
759
760	if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
761		return;
762
763	if (unlikely(test_bit(CFHSI_AWAKE, &cfhsi->bits))) {
764		/* It happenes when wakeup is requested by
765		 * both ends at the same time. */
766		clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
767		clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits);
768		return;
769	}
770
771	/* Activate wake line. */
772	cfhsi->ops->cfhsi_wake_up(cfhsi->ops);
773
774	netdev_dbg(cfhsi->ndev, "%s: Start waiting.\n",
775		__func__);
776
777	/* Wait for acknowledge. */
778	ret = CFHSI_WAKE_TOUT;
779	ret = wait_event_interruptible_timeout(cfhsi->wake_up_wait,
780					test_and_clear_bit(CFHSI_WAKE_UP_ACK,
781							&cfhsi->bits), ret);
782	if (unlikely(ret < 0)) {
783		/* Interrupted by signal. */
784		netdev_err(cfhsi->ndev, "%s: Signalled: %ld.\n",
785			__func__, ret);
786
787		clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
788		cfhsi->ops->cfhsi_wake_down(cfhsi->ops);
789		return;
790	} else if (!ret) {
791		bool ca_wake = false;
792		size_t fifo_occupancy = 0;
793
794		/* Wakeup timeout */
795		netdev_dbg(cfhsi->ndev, "%s: Timeout.\n",
796			__func__);
797
798		/* Check FIFO to check if modem has sent something. */
799		WARN_ON(cfhsi->ops->cfhsi_fifo_occupancy(cfhsi->ops,
800					&fifo_occupancy));
801
802		netdev_dbg(cfhsi->ndev, "%s: Bytes in FIFO: %u.\n",
803				__func__, (unsigned) fifo_occupancy);
804
805		/* Check if we misssed the interrupt. */
806		WARN_ON(cfhsi->ops->cfhsi_get_peer_wake(cfhsi->ops,
807							&ca_wake));
808
809		if (ca_wake) {
810			netdev_err(cfhsi->ndev, "%s: CA Wake missed !.\n",
811				__func__);
812
813			/* Clear the CFHSI_WAKE_UP_ACK bit to prevent race. */
814			clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits);
815
816			/* Continue execution. */
817			goto wake_ack;
818		}
819
820		clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
821		cfhsi->ops->cfhsi_wake_down(cfhsi->ops);
822		return;
823	}
824wake_ack:
825	netdev_dbg(cfhsi->ndev, "%s: Woken.\n",
826		__func__);
827
828	/* Clear power up bit. */
829	set_bit(CFHSI_AWAKE, &cfhsi->bits);
830	clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
831
832	/* Resume read operation. */
833	netdev_dbg(cfhsi->ndev, "%s: Start RX.\n", __func__);
834	res = cfhsi->ops->cfhsi_rx(cfhsi->rx_ptr, cfhsi->rx_len, cfhsi->ops);
835
836	if (WARN_ON(res < 0))
837		netdev_err(cfhsi->ndev, "%s: RX err %d.\n", __func__, res);
838
839	/* Clear power up acknowledment. */
840	clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits);
841
842	spin_lock_bh(&cfhsi->lock);
843
844	/* Resume transmit if queues are not empty. */
845	if (!cfhsi_tx_queue_len(cfhsi)) {
846		netdev_dbg(cfhsi->ndev, "%s: Peer wake, start timer.\n",
847			__func__);
848		/* Start inactivity timer. */
849		mod_timer(&cfhsi->inactivity_timer,
850				jiffies + cfhsi->cfg.inactivity_timeout);
851		spin_unlock_bh(&cfhsi->lock);
852		return;
853	}
854
855	netdev_dbg(cfhsi->ndev, "%s: Host wake.\n",
856		__func__);
857
858	spin_unlock_bh(&cfhsi->lock);
859
860	/* Create HSI frame. */
861	len = cfhsi_tx_frm((struct cfhsi_desc *)cfhsi->tx_buf, cfhsi);
862
863	if (likely(len > 0)) {
864		/* Set up new transfer. */
865		res = cfhsi->ops->cfhsi_tx(cfhsi->tx_buf, len, cfhsi->ops);
866		if (WARN_ON(res < 0)) {
867			netdev_err(cfhsi->ndev, "%s: TX error %d.\n",
868				__func__, res);
869			cfhsi_abort_tx(cfhsi);
870		}
871	} else {
872		netdev_err(cfhsi->ndev,
873				"%s: Failed to create HSI frame: %d.\n",
874				__func__, len);
875	}
876}
877
878static void cfhsi_wake_down(struct work_struct *work)
879{
880	long ret;
881	struct cfhsi *cfhsi = NULL;
882	size_t fifo_occupancy = 0;
883	int retry = CFHSI_WAKE_TOUT;
884
885	cfhsi = container_of(work, struct cfhsi, wake_down_work);
886	netdev_dbg(cfhsi->ndev, "%s.\n", __func__);
887
888	if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
889		return;
890
891	/* Deactivate wake line. */
892	cfhsi->ops->cfhsi_wake_down(cfhsi->ops);
893
894	/* Wait for acknowledge. */
895	ret = CFHSI_WAKE_TOUT;
896	ret = wait_event_interruptible_timeout(cfhsi->wake_down_wait,
897					test_and_clear_bit(CFHSI_WAKE_DOWN_ACK,
898							&cfhsi->bits), ret);
899	if (ret < 0) {
900		/* Interrupted by signal. */
901		netdev_err(cfhsi->ndev, "%s: Signalled: %ld.\n",
902			__func__, ret);
903		return;
904	} else if (!ret) {
905		bool ca_wake = true;
906
907		/* Timeout */
908		netdev_err(cfhsi->ndev, "%s: Timeout.\n", __func__);
909
910		/* Check if we misssed the interrupt. */
911		WARN_ON(cfhsi->ops->cfhsi_get_peer_wake(cfhsi->ops,
912							&ca_wake));
913		if (!ca_wake)
914			netdev_err(cfhsi->ndev, "%s: CA Wake missed !.\n",
915				__func__);
916	}
917
918	/* Check FIFO occupancy. */
919	while (retry) {
920		WARN_ON(cfhsi->ops->cfhsi_fifo_occupancy(cfhsi->ops,
921							&fifo_occupancy));
922
923		if (!fifo_occupancy)
924			break;
925
926		set_current_state(TASK_INTERRUPTIBLE);
927		schedule_timeout(1);
928		retry--;
929	}
930
931	if (!retry)
932		netdev_err(cfhsi->ndev, "%s: FIFO Timeout.\n", __func__);
933
934	/* Clear AWAKE condition. */
935	clear_bit(CFHSI_AWAKE, &cfhsi->bits);
936
937	/* Cancel pending RX requests. */
938	cfhsi->ops->cfhsi_rx_cancel(cfhsi->ops);
939}
940
941static void cfhsi_out_of_sync(struct work_struct *work)
942{
943	struct cfhsi *cfhsi = NULL;
944
945	cfhsi = container_of(work, struct cfhsi, out_of_sync_work);
946
947	rtnl_lock();
948	dev_close(cfhsi->ndev);
949	rtnl_unlock();
950}
951
952static void cfhsi_wake_up_cb(struct cfhsi_cb_ops *cb_ops)
953{
954	struct cfhsi *cfhsi = NULL;
955
956	cfhsi = container_of(cb_ops, struct cfhsi, cb_ops);
957	netdev_dbg(cfhsi->ndev, "%s.\n",
958		__func__);
959
960	set_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits);
961	wake_up_interruptible(&cfhsi->wake_up_wait);
962
963	if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))
964		return;
965
966	/* Schedule wake up work queue if the peer initiates. */
967	if (!test_and_set_bit(CFHSI_WAKE_UP, &cfhsi->bits))
968		queue_work(cfhsi->wq, &cfhsi->wake_up_work);
969}
970
971static void cfhsi_wake_down_cb(struct cfhsi_cb_ops *cb_ops)
972{
973	struct cfhsi *cfhsi = NULL;
974
975	cfhsi = container_of(cb_ops, struct cfhsi, cb_ops);
976	netdev_dbg(cfhsi->ndev, "%s.\n",
977		__func__);
978
979	/* Initiating low power is only permitted by the host (us). */
980	set_bit(CFHSI_WAKE_DOWN_ACK, &cfhsi->bits);
981	wake_up_interruptible(&cfhsi->wake_down_wait);
982}
983
984static void cfhsi_aggregation_tout(struct timer_list *t)
985{
986	struct cfhsi *cfhsi = from_timer(cfhsi, t, aggregation_timer);
987
988	netdev_dbg(cfhsi->ndev, "%s.\n",
989		__func__);
990
991	cfhsi_start_tx(cfhsi);
992}
993
994static netdev_tx_t cfhsi_xmit(struct sk_buff *skb, struct net_device *dev)
995{
996	struct cfhsi *cfhsi = NULL;
997	int start_xfer = 0;
998	int timer_active;
999	int prio;
1000
1001	if (!dev)
1002		return -EINVAL;
1003
1004	cfhsi = netdev_priv(dev);
1005
1006	switch (skb->priority) {
1007	case TC_PRIO_BESTEFFORT:
1008	case TC_PRIO_FILLER:
1009	case TC_PRIO_BULK:
1010		prio = CFHSI_PRIO_BEBK;
1011		break;
1012	case TC_PRIO_INTERACTIVE_BULK:
1013		prio = CFHSI_PRIO_VI;
1014		break;
1015	case TC_PRIO_INTERACTIVE:
1016		prio = CFHSI_PRIO_VO;
1017		break;
1018	case TC_PRIO_CONTROL:
1019	default:
1020		prio = CFHSI_PRIO_CTL;
1021		break;
1022	}
1023
1024	spin_lock_bh(&cfhsi->lock);
1025
1026	/* Update aggregation statistics  */
1027	cfhsi_update_aggregation_stats(cfhsi, skb, 1);
1028
1029	/* Queue the SKB */
1030	skb_queue_tail(&cfhsi->qhead[prio], skb);
1031
1032	/* Sanity check; xmit should not be called after unregister_netdev */
1033	if (WARN_ON(test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))) {
1034		spin_unlock_bh(&cfhsi->lock);
1035		cfhsi_abort_tx(cfhsi);
1036		return -EINVAL;
1037	}
1038
1039	/* Send flow off if number of packets is above high water mark. */
1040	if (!cfhsi->flow_off_sent &&
1041		cfhsi_tx_queue_len(cfhsi) > cfhsi->cfg.q_high_mark &&
1042		cfhsi->cfdev.flowctrl) {
1043		cfhsi->flow_off_sent = 1;
1044		cfhsi->cfdev.flowctrl(cfhsi->ndev, OFF);
1045	}
1046
1047	if (cfhsi->tx_state == CFHSI_TX_STATE_IDLE) {
1048		cfhsi->tx_state = CFHSI_TX_STATE_XFER;
1049		start_xfer = 1;
1050	}
1051
1052	if (!start_xfer) {
1053		/* Send aggregate if it is possible */
1054		bool aggregate_ready =
1055			cfhsi_can_send_aggregate(cfhsi) &&
1056			del_timer(&cfhsi->aggregation_timer) > 0;
1057		spin_unlock_bh(&cfhsi->lock);
1058		if (aggregate_ready)
1059			cfhsi_start_tx(cfhsi);
1060		return NETDEV_TX_OK;
1061	}
1062
1063	/* Delete inactivity timer if started. */
1064	timer_active = del_timer_sync(&cfhsi->inactivity_timer);
1065
1066	spin_unlock_bh(&cfhsi->lock);
1067
1068	if (timer_active) {
1069		struct cfhsi_desc *desc = (struct cfhsi_desc *)cfhsi->tx_buf;
1070		int len;
1071		int res;
1072
1073		/* Create HSI frame. */
1074		len = cfhsi_tx_frm(desc, cfhsi);
1075		WARN_ON(!len);
1076
1077		/* Set up new transfer. */
1078		res = cfhsi->ops->cfhsi_tx(cfhsi->tx_buf, len, cfhsi->ops);
1079		if (WARN_ON(res < 0)) {
1080			netdev_err(cfhsi->ndev, "%s: TX error %d.\n",
1081				__func__, res);
1082			cfhsi_abort_tx(cfhsi);
1083		}
1084	} else {
1085		/* Schedule wake up work queue if the we initiate. */
1086		if (!test_and_set_bit(CFHSI_WAKE_UP, &cfhsi->bits))
1087			queue_work(cfhsi->wq, &cfhsi->wake_up_work);
1088	}
1089
1090	return NETDEV_TX_OK;
1091}
1092
1093static const struct net_device_ops cfhsi_netdevops;
1094
1095static void cfhsi_setup(struct net_device *dev)
1096{
1097	int i;
1098	struct cfhsi *cfhsi = netdev_priv(dev);
1099	dev->features = 0;
1100	dev->type = ARPHRD_CAIF;
1101	dev->flags = IFF_POINTOPOINT | IFF_NOARP;
1102	dev->mtu = CFHSI_MAX_CAIF_FRAME_SZ;
1103	dev->priv_flags |= IFF_NO_QUEUE;
1104	dev->needs_free_netdev = true;
1105	dev->netdev_ops = &cfhsi_netdevops;
1106	for (i = 0; i < CFHSI_PRIO_LAST; ++i)
1107		skb_queue_head_init(&cfhsi->qhead[i]);
1108	cfhsi->cfdev.link_select = CAIF_LINK_HIGH_BANDW;
1109	cfhsi->cfdev.use_frag = false;
1110	cfhsi->cfdev.use_stx = false;
1111	cfhsi->cfdev.use_fcs = false;
1112	cfhsi->ndev = dev;
1113	cfhsi->cfg = hsi_default_config;
1114}
1115
1116static int cfhsi_open(struct net_device *ndev)
1117{
1118	struct cfhsi *cfhsi = netdev_priv(ndev);
1119	int res;
1120
1121	clear_bit(CFHSI_SHUTDOWN, &cfhsi->bits);
1122
1123	/* Initialize state vaiables. */
1124	cfhsi->tx_state = CFHSI_TX_STATE_IDLE;
1125	cfhsi->rx_state.state = CFHSI_RX_STATE_DESC;
1126
1127	/* Set flow info */
1128	cfhsi->flow_off_sent = 0;
1129
1130	/*
1131	 * Allocate a TX buffer with the size of a HSI packet descriptors
1132	 * and the necessary room for CAIF payload frames.
1133	 */
1134	cfhsi->tx_buf = kzalloc(CFHSI_BUF_SZ_TX, GFP_KERNEL);
1135	if (!cfhsi->tx_buf) {
1136		res = -ENODEV;
1137		goto err_alloc_tx;
1138	}
1139
1140	/*
1141	 * Allocate a RX buffer with the size of two HSI packet descriptors and
1142	 * the necessary room for CAIF payload frames.
1143	 */
1144	cfhsi->rx_buf = kzalloc(CFHSI_BUF_SZ_RX, GFP_KERNEL);
1145	if (!cfhsi->rx_buf) {
1146		res = -ENODEV;
1147		goto err_alloc_rx;
1148	}
1149
1150	cfhsi->rx_flip_buf = kzalloc(CFHSI_BUF_SZ_RX, GFP_KERNEL);
1151	if (!cfhsi->rx_flip_buf) {
1152		res = -ENODEV;
1153		goto err_alloc_rx_flip;
1154	}
1155
1156	/* Initialize aggregation timeout */
1157	cfhsi->cfg.aggregation_timeout = hsi_default_config.aggregation_timeout;
1158
1159	/* Initialize recieve vaiables. */
1160	cfhsi->rx_ptr = cfhsi->rx_buf;
1161	cfhsi->rx_len = CFHSI_DESC_SZ;
1162
1163	/* Initialize spin locks. */
1164	spin_lock_init(&cfhsi->lock);
1165
1166	/* Set up the driver. */
1167	cfhsi->cb_ops.tx_done_cb = cfhsi_tx_done_cb;
1168	cfhsi->cb_ops.rx_done_cb = cfhsi_rx_done_cb;
1169	cfhsi->cb_ops.wake_up_cb = cfhsi_wake_up_cb;
1170	cfhsi->cb_ops.wake_down_cb = cfhsi_wake_down_cb;
1171
1172	/* Initialize the work queues. */
1173	INIT_WORK(&cfhsi->wake_up_work, cfhsi_wake_up);
1174	INIT_WORK(&cfhsi->wake_down_work, cfhsi_wake_down);
1175	INIT_WORK(&cfhsi->out_of_sync_work, cfhsi_out_of_sync);
1176
1177	/* Clear all bit fields. */
1178	clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits);
1179	clear_bit(CFHSI_WAKE_DOWN_ACK, &cfhsi->bits);
1180	clear_bit(CFHSI_WAKE_UP, &cfhsi->bits);
1181	clear_bit(CFHSI_AWAKE, &cfhsi->bits);
1182
1183	/* Create work thread. */
1184	cfhsi->wq = alloc_ordered_workqueue(cfhsi->ndev->name, WQ_MEM_RECLAIM);
1185	if (!cfhsi->wq) {
1186		netdev_err(cfhsi->ndev, "%s: Failed to create work queue.\n",
1187			__func__);
1188		res = -ENODEV;
1189		goto err_create_wq;
1190	}
1191
1192	/* Initialize wait queues. */
1193	init_waitqueue_head(&cfhsi->wake_up_wait);
1194	init_waitqueue_head(&cfhsi->wake_down_wait);
1195	init_waitqueue_head(&cfhsi->flush_fifo_wait);
1196
1197	/* Setup the inactivity timer. */
1198	timer_setup(&cfhsi->inactivity_timer, cfhsi_inactivity_tout, 0);
1199	/* Setup the slowpath RX timer. */
1200	timer_setup(&cfhsi->rx_slowpath_timer, cfhsi_rx_slowpath, 0);
1201	/* Setup the aggregation timer. */
1202	timer_setup(&cfhsi->aggregation_timer, cfhsi_aggregation_tout, 0);
1203
1204	/* Activate HSI interface. */
1205	res = cfhsi->ops->cfhsi_up(cfhsi->ops);
1206	if (res) {
1207		netdev_err(cfhsi->ndev,
1208			"%s: can't activate HSI interface: %d.\n",
1209			__func__, res);
1210		goto err_activate;
1211	}
1212
1213	/* Flush FIFO */
1214	res = cfhsi_flush_fifo(cfhsi);
1215	if (res) {
1216		netdev_err(cfhsi->ndev, "%s: Can't flush FIFO: %d.\n",
1217			__func__, res);
1218		goto err_net_reg;
1219	}
1220	return res;
1221
1222 err_net_reg:
1223	cfhsi->ops->cfhsi_down(cfhsi->ops);
1224 err_activate:
1225	destroy_workqueue(cfhsi->wq);
1226 err_create_wq:
1227	kfree(cfhsi->rx_flip_buf);
1228 err_alloc_rx_flip:
1229	kfree(cfhsi->rx_buf);
1230 err_alloc_rx:
1231	kfree(cfhsi->tx_buf);
1232 err_alloc_tx:
1233	return res;
1234}
1235
1236static int cfhsi_close(struct net_device *ndev)
1237{
1238	struct cfhsi *cfhsi = netdev_priv(ndev);
1239	u8 *tx_buf, *rx_buf, *flip_buf;
1240
1241	/* going to shutdown driver */
1242	set_bit(CFHSI_SHUTDOWN, &cfhsi->bits);
1243
1244	/* Delete timers if pending */
1245	del_timer_sync(&cfhsi->inactivity_timer);
1246	del_timer_sync(&cfhsi->rx_slowpath_timer);
1247	del_timer_sync(&cfhsi->aggregation_timer);
1248
1249	/* Cancel pending RX request (if any) */
1250	cfhsi->ops->cfhsi_rx_cancel(cfhsi->ops);
1251
1252	/* Destroy workqueue */
1253	destroy_workqueue(cfhsi->wq);
1254
1255	/* Store bufferes: will be freed later. */
1256	tx_buf = cfhsi->tx_buf;
1257	rx_buf = cfhsi->rx_buf;
1258	flip_buf = cfhsi->rx_flip_buf;
1259	/* Flush transmit queues. */
1260	cfhsi_abort_tx(cfhsi);
1261
1262	/* Deactivate interface */
1263	cfhsi->ops->cfhsi_down(cfhsi->ops);
1264
1265	/* Free buffers. */
1266	kfree(tx_buf);
1267	kfree(rx_buf);
1268	kfree(flip_buf);
1269	return 0;
1270}
1271
1272static void cfhsi_uninit(struct net_device *dev)
1273{
1274	struct cfhsi *cfhsi = netdev_priv(dev);
1275	ASSERT_RTNL();
1276	symbol_put(cfhsi_get_device);
1277	list_del(&cfhsi->list);
1278}
1279
1280static const struct net_device_ops cfhsi_netdevops = {
1281	.ndo_uninit = cfhsi_uninit,
1282	.ndo_open = cfhsi_open,
1283	.ndo_stop = cfhsi_close,
1284	.ndo_start_xmit = cfhsi_xmit
1285};
1286
1287static void cfhsi_netlink_parms(struct nlattr *data[], struct cfhsi *cfhsi)
1288{
1289	int i;
1290
1291	if (!data) {
1292		pr_debug("no params data found\n");
1293		return;
1294	}
1295
1296	i = __IFLA_CAIF_HSI_INACTIVITY_TOUT;
1297	/*
1298	 * Inactivity timeout in millisecs. Lowest possible value is 1,
1299	 * and highest possible is NEXT_TIMER_MAX_DELTA.
1300	 */
1301	if (data[i]) {
1302		u32 inactivity_timeout = nla_get_u32(data[i]);
1303		/* Pre-calculate inactivity timeout. */
1304		cfhsi->cfg.inactivity_timeout =	inactivity_timeout * HZ / 1000;
1305		if (cfhsi->cfg.inactivity_timeout == 0)
1306			cfhsi->cfg.inactivity_timeout = 1;
1307		else if (cfhsi->cfg.inactivity_timeout > NEXT_TIMER_MAX_DELTA)
1308			cfhsi->cfg.inactivity_timeout = NEXT_TIMER_MAX_DELTA;
1309	}
1310
1311	i = __IFLA_CAIF_HSI_AGGREGATION_TOUT;
1312	if (data[i])
1313		cfhsi->cfg.aggregation_timeout = nla_get_u32(data[i]);
1314
1315	i = __IFLA_CAIF_HSI_HEAD_ALIGN;
1316	if (data[i])
1317		cfhsi->cfg.head_align = nla_get_u32(data[i]);
1318
1319	i = __IFLA_CAIF_HSI_TAIL_ALIGN;
1320	if (data[i])
1321		cfhsi->cfg.tail_align = nla_get_u32(data[i]);
1322
1323	i = __IFLA_CAIF_HSI_QHIGH_WATERMARK;
1324	if (data[i])
1325		cfhsi->cfg.q_high_mark = nla_get_u32(data[i]);
1326
1327	i = __IFLA_CAIF_HSI_QLOW_WATERMARK;
1328	if (data[i])
1329		cfhsi->cfg.q_low_mark = nla_get_u32(data[i]);
1330}
1331
1332static int caif_hsi_changelink(struct net_device *dev, struct nlattr *tb[],
1333			       struct nlattr *data[],
1334			       struct netlink_ext_ack *extack)
1335{
1336	cfhsi_netlink_parms(data, netdev_priv(dev));
1337	netdev_state_change(dev);
1338	return 0;
1339}
1340
1341static const struct nla_policy caif_hsi_policy[__IFLA_CAIF_HSI_MAX + 1] = {
1342	[__IFLA_CAIF_HSI_INACTIVITY_TOUT] = { .type = NLA_U32, .len = 4 },
1343	[__IFLA_CAIF_HSI_AGGREGATION_TOUT] = { .type = NLA_U32, .len = 4 },
1344	[__IFLA_CAIF_HSI_HEAD_ALIGN] = { .type = NLA_U32, .len = 4 },
1345	[__IFLA_CAIF_HSI_TAIL_ALIGN] = { .type = NLA_U32, .len = 4 },
1346	[__IFLA_CAIF_HSI_QHIGH_WATERMARK] = { .type = NLA_U32, .len = 4 },
1347	[__IFLA_CAIF_HSI_QLOW_WATERMARK] = { .type = NLA_U32, .len = 4 },
1348};
1349
1350static size_t caif_hsi_get_size(const struct net_device *dev)
1351{
1352	int i;
1353	size_t s = 0;
1354	for (i = __IFLA_CAIF_HSI_UNSPEC + 1; i < __IFLA_CAIF_HSI_MAX; i++)
1355		s += nla_total_size(caif_hsi_policy[i].len);
1356	return s;
1357}
1358
1359static int caif_hsi_fill_info(struct sk_buff *skb, const struct net_device *dev)
1360{
1361	struct cfhsi *cfhsi = netdev_priv(dev);
1362
1363	if (nla_put_u32(skb, __IFLA_CAIF_HSI_INACTIVITY_TOUT,
1364			cfhsi->cfg.inactivity_timeout) ||
1365	    nla_put_u32(skb, __IFLA_CAIF_HSI_AGGREGATION_TOUT,
1366			cfhsi->cfg.aggregation_timeout) ||
1367	    nla_put_u32(skb, __IFLA_CAIF_HSI_HEAD_ALIGN,
1368			cfhsi->cfg.head_align) ||
1369	    nla_put_u32(skb, __IFLA_CAIF_HSI_TAIL_ALIGN,
1370			cfhsi->cfg.tail_align) ||
1371	    nla_put_u32(skb, __IFLA_CAIF_HSI_QHIGH_WATERMARK,
1372			cfhsi->cfg.q_high_mark) ||
1373	    nla_put_u32(skb, __IFLA_CAIF_HSI_QLOW_WATERMARK,
1374			cfhsi->cfg.q_low_mark))
1375		return -EMSGSIZE;
1376
1377	return 0;
1378}
1379
1380static int caif_hsi_newlink(struct net *src_net, struct net_device *dev,
1381			    struct nlattr *tb[], struct nlattr *data[],
1382			    struct netlink_ext_ack *extack)
1383{
1384	struct cfhsi *cfhsi = NULL;
1385	struct cfhsi_ops *(*get_ops)(void);
1386
1387	ASSERT_RTNL();
1388
1389	cfhsi = netdev_priv(dev);
1390	cfhsi_netlink_parms(data, cfhsi);
1391
1392	get_ops = symbol_get(cfhsi_get_ops);
1393	if (!get_ops) {
1394		pr_err("%s: failed to get the cfhsi_ops\n", __func__);
1395		return -ENODEV;
1396	}
1397
1398	/* Assign the HSI device. */
1399	cfhsi->ops = (*get_ops)();
1400	if (!cfhsi->ops) {
1401		pr_err("%s: failed to get the cfhsi_ops\n", __func__);
1402		goto err;
1403	}
1404
1405	/* Assign the driver to this HSI device. */
1406	cfhsi->ops->cb_ops = &cfhsi->cb_ops;
1407	if (register_netdevice(dev)) {
1408		pr_warn("%s: caif_hsi device registration failed\n", __func__);
1409		goto err;
1410	}
1411	/* Add CAIF HSI device to list. */
1412	list_add_tail(&cfhsi->list, &cfhsi_list);
1413
1414	return 0;
1415err:
1416	symbol_put(cfhsi_get_ops);
1417	return -ENODEV;
1418}
1419
1420static struct rtnl_link_ops caif_hsi_link_ops __read_mostly = {
1421	.kind		= "cfhsi",
1422	.priv_size	= sizeof(struct cfhsi),
1423	.setup		= cfhsi_setup,
1424	.maxtype	= __IFLA_CAIF_HSI_MAX,
1425	.policy	= caif_hsi_policy,
1426	.newlink	= caif_hsi_newlink,
1427	.changelink	= caif_hsi_changelink,
1428	.get_size	= caif_hsi_get_size,
1429	.fill_info	= caif_hsi_fill_info,
1430};
1431
1432static void __exit cfhsi_exit_module(void)
1433{
1434	struct list_head *list_node;
1435	struct list_head *n;
1436	struct cfhsi *cfhsi;
1437
1438	rtnl_link_unregister(&caif_hsi_link_ops);
1439
1440	rtnl_lock();
1441	list_for_each_safe(list_node, n, &cfhsi_list) {
1442		cfhsi = list_entry(list_node, struct cfhsi, list);
1443		unregister_netdevice(cfhsi->ndev);
1444	}
1445	rtnl_unlock();
1446}
1447
1448static int __init cfhsi_init_module(void)
1449{
1450	return rtnl_link_register(&caif_hsi_link_ops);
1451}
1452
1453module_init(cfhsi_init_module);
1454module_exit(cfhsi_exit_module);
1455