1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) ST-Ericsson AB 2010
4 * Author:	Sjur Brendeland
5 */
6
7#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
8
9#include <linux/stddef.h>
10#include <linux/spinlock.h>
11#include <linux/slab.h>
12#include <linux/pkt_sched.h>
13#include <net/caif/caif_layer.h>
14#include <net/caif/cfpkt.h>
15#include <net/caif/cfctrl.h>
16
17#define container_obj(layr) container_of(layr, struct cfctrl, serv.layer)
18#define UTILITY_NAME_LENGTH 16
19#define CFPKT_CTRL_PKT_LEN 20
20
21#ifdef CAIF_NO_LOOP
22static int handle_loop(struct cfctrl *ctrl,
23		       int cmd, struct cfpkt *pkt){
24	return -1;
25}
26#else
27static int handle_loop(struct cfctrl *ctrl,
28		       int cmd, struct cfpkt *pkt);
29#endif
30static int cfctrl_recv(struct cflayer *layr, struct cfpkt *pkt);
31static void cfctrl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
32			   int phyid);
33
34
35struct cflayer *cfctrl_create(void)
36{
37	struct dev_info dev_info;
38	struct cfctrl *this =
39		kzalloc(sizeof(struct cfctrl), GFP_ATOMIC);
40	if (!this)
41		return NULL;
42	caif_assert(offsetof(struct cfctrl, serv.layer) == 0);
43	memset(&dev_info, 0, sizeof(dev_info));
44	dev_info.id = 0xff;
45	cfsrvl_init(&this->serv, 0, &dev_info, false);
46	atomic_set(&this->req_seq_no, 1);
47	atomic_set(&this->rsp_seq_no, 1);
48	this->serv.layer.receive = cfctrl_recv;
49	sprintf(this->serv.layer.name, "ctrl");
50	this->serv.layer.ctrlcmd = cfctrl_ctrlcmd;
51#ifndef CAIF_NO_LOOP
52	spin_lock_init(&this->loop_linkid_lock);
53	this->loop_linkid = 1;
54#endif
55	spin_lock_init(&this->info_list_lock);
56	INIT_LIST_HEAD(&this->list);
57	return &this->serv.layer;
58}
59
60void cfctrl_remove(struct cflayer *layer)
61{
62	struct cfctrl_request_info *p, *tmp;
63	struct cfctrl *ctrl = container_obj(layer);
64
65	spin_lock_bh(&ctrl->info_list_lock);
66	list_for_each_entry_safe(p, tmp, &ctrl->list, list) {
67		list_del(&p->list);
68		kfree(p);
69	}
70	spin_unlock_bh(&ctrl->info_list_lock);
71	kfree(layer);
72}
73
74static bool param_eq(const struct cfctrl_link_param *p1,
75		     const struct cfctrl_link_param *p2)
76{
77	bool eq =
78	    p1->linktype == p2->linktype &&
79	    p1->priority == p2->priority &&
80	    p1->phyid == p2->phyid &&
81	    p1->endpoint == p2->endpoint && p1->chtype == p2->chtype;
82
83	if (!eq)
84		return false;
85
86	switch (p1->linktype) {
87	case CFCTRL_SRV_VEI:
88		return true;
89	case CFCTRL_SRV_DATAGRAM:
90		return p1->u.datagram.connid == p2->u.datagram.connid;
91	case CFCTRL_SRV_RFM:
92		return
93		    p1->u.rfm.connid == p2->u.rfm.connid &&
94		    strcmp(p1->u.rfm.volume, p2->u.rfm.volume) == 0;
95	case CFCTRL_SRV_UTIL:
96		return
97		    p1->u.utility.fifosize_kb == p2->u.utility.fifosize_kb
98		    && p1->u.utility.fifosize_bufs ==
99		    p2->u.utility.fifosize_bufs
100		    && strcmp(p1->u.utility.name, p2->u.utility.name) == 0
101		    && p1->u.utility.paramlen == p2->u.utility.paramlen
102		    && memcmp(p1->u.utility.params, p2->u.utility.params,
103			      p1->u.utility.paramlen) == 0;
104
105	case CFCTRL_SRV_VIDEO:
106		return p1->u.video.connid == p2->u.video.connid;
107	case CFCTRL_SRV_DBG:
108		return true;
109	case CFCTRL_SRV_DECM:
110		return false;
111	default:
112		return false;
113	}
114	return false;
115}
116
117static bool cfctrl_req_eq(const struct cfctrl_request_info *r1,
118			  const struct cfctrl_request_info *r2)
119{
120	if (r1->cmd != r2->cmd)
121		return false;
122	if (r1->cmd == CFCTRL_CMD_LINK_SETUP)
123		return param_eq(&r1->param, &r2->param);
124	else
125		return r1->channel_id == r2->channel_id;
126}
127
128/* Insert request at the end */
129static void cfctrl_insert_req(struct cfctrl *ctrl,
130			      struct cfctrl_request_info *req)
131{
132	spin_lock_bh(&ctrl->info_list_lock);
133	atomic_inc(&ctrl->req_seq_no);
134	req->sequence_no = atomic_read(&ctrl->req_seq_no);
135	list_add_tail(&req->list, &ctrl->list);
136	spin_unlock_bh(&ctrl->info_list_lock);
137}
138
139/* Compare and remove request */
140static struct cfctrl_request_info *cfctrl_remove_req(struct cfctrl *ctrl,
141						struct cfctrl_request_info *req)
142{
143	struct cfctrl_request_info *p, *tmp, *first;
144
145	first = list_first_entry(&ctrl->list, struct cfctrl_request_info, list);
146
147	list_for_each_entry_safe(p, tmp, &ctrl->list, list) {
148		if (cfctrl_req_eq(req, p)) {
149			if (p != first)
150				pr_warn("Requests are not received in order\n");
151
152			atomic_set(&ctrl->rsp_seq_no,
153					 p->sequence_no);
154			list_del(&p->list);
155			goto out;
156		}
157	}
158	p = NULL;
159out:
160	return p;
161}
162
163struct cfctrl_rsp *cfctrl_get_respfuncs(struct cflayer *layer)
164{
165	struct cfctrl *this = container_obj(layer);
166	return &this->res;
167}
168
169static void init_info(struct caif_payload_info *info, struct cfctrl *cfctrl)
170{
171	info->hdr_len = 0;
172	info->channel_id = cfctrl->serv.layer.id;
173	info->dev_info = &cfctrl->serv.dev_info;
174}
175
176void cfctrl_enum_req(struct cflayer *layer, u8 physlinkid)
177{
178	struct cfpkt *pkt;
179	struct cfctrl *cfctrl = container_obj(layer);
180	struct cflayer *dn = cfctrl->serv.layer.dn;
181
182	if (!dn) {
183		pr_debug("not able to send enum request\n");
184		return;
185	}
186	pkt = cfpkt_create(CFPKT_CTRL_PKT_LEN);
187	if (!pkt)
188		return;
189	caif_assert(offsetof(struct cfctrl, serv.layer) == 0);
190	init_info(cfpkt_info(pkt), cfctrl);
191	cfpkt_info(pkt)->dev_info->id = physlinkid;
192	cfctrl->serv.dev_info.id = physlinkid;
193	cfpkt_addbdy(pkt, CFCTRL_CMD_ENUM);
194	cfpkt_addbdy(pkt, physlinkid);
195	cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
196	dn->transmit(dn, pkt);
197}
198
199int cfctrl_linkup_request(struct cflayer *layer,
200			  struct cfctrl_link_param *param,
201			  struct cflayer *user_layer)
202{
203	struct cfctrl *cfctrl = container_obj(layer);
204	u32 tmp32;
205	u16 tmp16;
206	u8 tmp8;
207	struct cfctrl_request_info *req;
208	int ret;
209	char utility_name[16];
210	struct cfpkt *pkt;
211	struct cflayer *dn = cfctrl->serv.layer.dn;
212
213	if (!dn) {
214		pr_debug("not able to send linkup request\n");
215		return -ENODEV;
216	}
217
218	if (cfctrl_cancel_req(layer, user_layer) > 0) {
219		/* Slight Paranoia, check if already connecting */
220		pr_err("Duplicate connect request for same client\n");
221		WARN_ON(1);
222		return -EALREADY;
223	}
224
225	pkt = cfpkt_create(CFPKT_CTRL_PKT_LEN);
226	if (!pkt)
227		return -ENOMEM;
228	cfpkt_addbdy(pkt, CFCTRL_CMD_LINK_SETUP);
229	cfpkt_addbdy(pkt, (param->chtype << 4) | param->linktype);
230	cfpkt_addbdy(pkt, (param->priority << 3) | param->phyid);
231	cfpkt_addbdy(pkt, param->endpoint & 0x03);
232
233	switch (param->linktype) {
234	case CFCTRL_SRV_VEI:
235		break;
236	case CFCTRL_SRV_VIDEO:
237		cfpkt_addbdy(pkt, (u8) param->u.video.connid);
238		break;
239	case CFCTRL_SRV_DBG:
240		break;
241	case CFCTRL_SRV_DATAGRAM:
242		tmp32 = cpu_to_le32(param->u.datagram.connid);
243		cfpkt_add_body(pkt, &tmp32, 4);
244		break;
245	case CFCTRL_SRV_RFM:
246		/* Construct a frame, convert DatagramConnectionID to network
247		 * format long and copy it out...
248		 */
249		tmp32 = cpu_to_le32(param->u.rfm.connid);
250		cfpkt_add_body(pkt, &tmp32, 4);
251		/* Add volume name, including zero termination... */
252		cfpkt_add_body(pkt, param->u.rfm.volume,
253			       strlen(param->u.rfm.volume) + 1);
254		break;
255	case CFCTRL_SRV_UTIL:
256		tmp16 = cpu_to_le16(param->u.utility.fifosize_kb);
257		cfpkt_add_body(pkt, &tmp16, 2);
258		tmp16 = cpu_to_le16(param->u.utility.fifosize_bufs);
259		cfpkt_add_body(pkt, &tmp16, 2);
260		memset(utility_name, 0, sizeof(utility_name));
261		strscpy(utility_name, param->u.utility.name,
262			UTILITY_NAME_LENGTH);
263		cfpkt_add_body(pkt, utility_name, UTILITY_NAME_LENGTH);
264		tmp8 = param->u.utility.paramlen;
265		cfpkt_add_body(pkt, &tmp8, 1);
266		cfpkt_add_body(pkt, param->u.utility.params,
267			       param->u.utility.paramlen);
268		break;
269	default:
270		pr_warn("Request setup of bad link type = %d\n",
271			param->linktype);
272		cfpkt_destroy(pkt);
273		return -EINVAL;
274	}
275	req = kzalloc(sizeof(*req), GFP_KERNEL);
276	if (!req) {
277		cfpkt_destroy(pkt);
278		return -ENOMEM;
279	}
280
281	req->client_layer = user_layer;
282	req->cmd = CFCTRL_CMD_LINK_SETUP;
283	req->param = *param;
284	cfctrl_insert_req(cfctrl, req);
285	init_info(cfpkt_info(pkt), cfctrl);
286	/*
287	 * NOTE:Always send linkup and linkdown request on the same
288	 *	device as the payload. Otherwise old queued up payload
289	 *	might arrive with the newly allocated channel ID.
290	 */
291	cfpkt_info(pkt)->dev_info->id = param->phyid;
292	cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
293	ret =
294	    dn->transmit(dn, pkt);
295	if (ret < 0) {
296		int count;
297
298		count = cfctrl_cancel_req(&cfctrl->serv.layer,
299						user_layer);
300		if (count != 1) {
301			pr_err("Could not remove request (%d)", count);
302			return -ENODEV;
303		}
304	}
305	return 0;
306}
307
308int cfctrl_linkdown_req(struct cflayer *layer, u8 channelid,
309			struct cflayer *client)
310{
311	int ret;
312	struct cfpkt *pkt;
313	struct cfctrl *cfctrl = container_obj(layer);
314	struct cflayer *dn = cfctrl->serv.layer.dn;
315
316	if (!dn) {
317		pr_debug("not able to send link-down request\n");
318		return -ENODEV;
319	}
320	pkt = cfpkt_create(CFPKT_CTRL_PKT_LEN);
321	if (!pkt)
322		return -ENOMEM;
323	cfpkt_addbdy(pkt, CFCTRL_CMD_LINK_DESTROY);
324	cfpkt_addbdy(pkt, channelid);
325	init_info(cfpkt_info(pkt), cfctrl);
326	cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
327	ret =
328	    dn->transmit(dn, pkt);
329#ifndef CAIF_NO_LOOP
330	cfctrl->loop_linkused[channelid] = 0;
331#endif
332	return ret;
333}
334
335int cfctrl_cancel_req(struct cflayer *layr, struct cflayer *adap_layer)
336{
337	struct cfctrl_request_info *p, *tmp;
338	struct cfctrl *ctrl = container_obj(layr);
339	int found = 0;
340	spin_lock_bh(&ctrl->info_list_lock);
341
342	list_for_each_entry_safe(p, tmp, &ctrl->list, list) {
343		if (p->client_layer == adap_layer) {
344			list_del(&p->list);
345			kfree(p);
346			found++;
347		}
348	}
349
350	spin_unlock_bh(&ctrl->info_list_lock);
351	return found;
352}
353
354static int cfctrl_recv(struct cflayer *layer, struct cfpkt *pkt)
355{
356	u8 cmdrsp;
357	u8 cmd;
358	int ret = -1;
359	u8 len;
360	u8 param[255];
361	u8 linkid = 0;
362	struct cfctrl *cfctrl = container_obj(layer);
363	struct cfctrl_request_info rsp, *req;
364
365
366	cmdrsp = cfpkt_extr_head_u8(pkt);
367	cmd = cmdrsp & CFCTRL_CMD_MASK;
368	if (cmd != CFCTRL_CMD_LINK_ERR
369	    && CFCTRL_RSP_BIT != (CFCTRL_RSP_BIT & cmdrsp)
370		&& CFCTRL_ERR_BIT != (CFCTRL_ERR_BIT & cmdrsp)) {
371		if (handle_loop(cfctrl, cmd, pkt) != 0)
372			cmdrsp |= CFCTRL_ERR_BIT;
373	}
374
375	switch (cmd) {
376	case CFCTRL_CMD_LINK_SETUP:
377		{
378			enum cfctrl_srv serv;
379			enum cfctrl_srv servtype;
380			u8 endpoint;
381			u8 physlinkid;
382			u8 prio;
383			u8 tmp;
384			u8 *cp;
385			int i;
386			struct cfctrl_link_param linkparam;
387			memset(&linkparam, 0, sizeof(linkparam));
388
389			tmp = cfpkt_extr_head_u8(pkt);
390
391			serv = tmp & CFCTRL_SRV_MASK;
392			linkparam.linktype = serv;
393
394			servtype = tmp >> 4;
395			linkparam.chtype = servtype;
396
397			tmp = cfpkt_extr_head_u8(pkt);
398			physlinkid = tmp & 0x07;
399			prio = tmp >> 3;
400
401			linkparam.priority = prio;
402			linkparam.phyid = physlinkid;
403			endpoint = cfpkt_extr_head_u8(pkt);
404			linkparam.endpoint = endpoint & 0x03;
405
406			switch (serv) {
407			case CFCTRL_SRV_VEI:
408			case CFCTRL_SRV_DBG:
409				if (CFCTRL_ERR_BIT & cmdrsp)
410					break;
411				/* Link ID */
412				linkid = cfpkt_extr_head_u8(pkt);
413				break;
414			case CFCTRL_SRV_VIDEO:
415				tmp = cfpkt_extr_head_u8(pkt);
416				linkparam.u.video.connid = tmp;
417				if (CFCTRL_ERR_BIT & cmdrsp)
418					break;
419				/* Link ID */
420				linkid = cfpkt_extr_head_u8(pkt);
421				break;
422
423			case CFCTRL_SRV_DATAGRAM:
424				linkparam.u.datagram.connid =
425				    cfpkt_extr_head_u32(pkt);
426				if (CFCTRL_ERR_BIT & cmdrsp)
427					break;
428				/* Link ID */
429				linkid = cfpkt_extr_head_u8(pkt);
430				break;
431			case CFCTRL_SRV_RFM:
432				/* Construct a frame, convert
433				 * DatagramConnectionID
434				 * to network format long and copy it out...
435				 */
436				linkparam.u.rfm.connid =
437				    cfpkt_extr_head_u32(pkt);
438				cp = (u8 *) linkparam.u.rfm.volume;
439				for (tmp = cfpkt_extr_head_u8(pkt);
440				     cfpkt_more(pkt) && tmp != '\0';
441				     tmp = cfpkt_extr_head_u8(pkt))
442					*cp++ = tmp;
443				*cp = '\0';
444
445				if (CFCTRL_ERR_BIT & cmdrsp)
446					break;
447				/* Link ID */
448				linkid = cfpkt_extr_head_u8(pkt);
449
450				break;
451			case CFCTRL_SRV_UTIL:
452				/* Construct a frame, convert
453				 * DatagramConnectionID
454				 * to network format long and copy it out...
455				 */
456				/* Fifosize KB */
457				linkparam.u.utility.fifosize_kb =
458				    cfpkt_extr_head_u16(pkt);
459				/* Fifosize bufs */
460				linkparam.u.utility.fifosize_bufs =
461				    cfpkt_extr_head_u16(pkt);
462				/* name */
463				cp = (u8 *) linkparam.u.utility.name;
464				caif_assert(sizeof(linkparam.u.utility.name)
465					     >= UTILITY_NAME_LENGTH);
466				for (i = 0;
467				     i < UTILITY_NAME_LENGTH
468				     && cfpkt_more(pkt); i++) {
469					tmp = cfpkt_extr_head_u8(pkt);
470					*cp++ = tmp;
471				}
472				/* Length */
473				len = cfpkt_extr_head_u8(pkt);
474				linkparam.u.utility.paramlen = len;
475				/* Param Data */
476				cp = linkparam.u.utility.params;
477				while (cfpkt_more(pkt) && len--) {
478					tmp = cfpkt_extr_head_u8(pkt);
479					*cp++ = tmp;
480				}
481				if (CFCTRL_ERR_BIT & cmdrsp)
482					break;
483				/* Link ID */
484				linkid = cfpkt_extr_head_u8(pkt);
485				/* Length */
486				len = cfpkt_extr_head_u8(pkt);
487				/* Param Data */
488				cfpkt_extr_head(pkt, &param, len);
489				break;
490			default:
491				pr_warn("Request setup, invalid type (%d)\n",
492					serv);
493				goto error;
494			}
495
496			rsp.cmd = cmd;
497			rsp.param = linkparam;
498			spin_lock_bh(&cfctrl->info_list_lock);
499			req = cfctrl_remove_req(cfctrl, &rsp);
500
501			if (CFCTRL_ERR_BIT == (CFCTRL_ERR_BIT & cmdrsp) ||
502				cfpkt_erroneous(pkt)) {
503				pr_err("Invalid O/E bit or parse error "
504						"on CAIF control channel\n");
505				cfctrl->res.reject_rsp(cfctrl->serv.layer.up,
506						       0,
507						       req ? req->client_layer
508						       : NULL);
509			} else {
510				cfctrl->res.linksetup_rsp(cfctrl->serv.
511							  layer.up, linkid,
512							  serv, physlinkid,
513							  req ? req->
514							  client_layer : NULL);
515			}
516
517			kfree(req);
518
519			spin_unlock_bh(&cfctrl->info_list_lock);
520		}
521		break;
522	case CFCTRL_CMD_LINK_DESTROY:
523		linkid = cfpkt_extr_head_u8(pkt);
524		cfctrl->res.linkdestroy_rsp(cfctrl->serv.layer.up, linkid);
525		break;
526	case CFCTRL_CMD_LINK_ERR:
527		pr_err("Frame Error Indication received\n");
528		cfctrl->res.linkerror_ind();
529		break;
530	case CFCTRL_CMD_ENUM:
531		cfctrl->res.enum_rsp();
532		break;
533	case CFCTRL_CMD_SLEEP:
534		cfctrl->res.sleep_rsp();
535		break;
536	case CFCTRL_CMD_WAKE:
537		cfctrl->res.wake_rsp();
538		break;
539	case CFCTRL_CMD_LINK_RECONF:
540		cfctrl->res.restart_rsp();
541		break;
542	case CFCTRL_CMD_RADIO_SET:
543		cfctrl->res.radioset_rsp();
544		break;
545	default:
546		pr_err("Unrecognized Control Frame\n");
547		goto error;
548	}
549	ret = 0;
550error:
551	cfpkt_destroy(pkt);
552	return ret;
553}
554
555static void cfctrl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
556			   int phyid)
557{
558	struct cfctrl *this = container_obj(layr);
559	switch (ctrl) {
560	case _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND:
561	case CAIF_CTRLCMD_FLOW_OFF_IND:
562		spin_lock_bh(&this->info_list_lock);
563		if (!list_empty(&this->list))
564			pr_debug("Received flow off in control layer\n");
565		spin_unlock_bh(&this->info_list_lock);
566		break;
567	case _CAIF_CTRLCMD_PHYIF_DOWN_IND: {
568		struct cfctrl_request_info *p, *tmp;
569
570		/* Find all connect request and report failure */
571		spin_lock_bh(&this->info_list_lock);
572		list_for_each_entry_safe(p, tmp, &this->list, list) {
573			if (p->param.phyid == phyid) {
574				list_del(&p->list);
575				p->client_layer->ctrlcmd(p->client_layer,
576						CAIF_CTRLCMD_INIT_FAIL_RSP,
577						phyid);
578				kfree(p);
579			}
580		}
581		spin_unlock_bh(&this->info_list_lock);
582		break;
583	}
584	default:
585		break;
586	}
587}
588
589#ifndef CAIF_NO_LOOP
590static int handle_loop(struct cfctrl *ctrl, int cmd, struct cfpkt *pkt)
591{
592	static int last_linkid;
593	static int dec;
594	u8 linkid, linktype, tmp;
595	switch (cmd) {
596	case CFCTRL_CMD_LINK_SETUP:
597		spin_lock_bh(&ctrl->loop_linkid_lock);
598		if (!dec) {
599			for (linkid = last_linkid + 1; linkid < 254; linkid++)
600				if (!ctrl->loop_linkused[linkid])
601					goto found;
602		}
603		dec = 1;
604		for (linkid = last_linkid - 1; linkid > 1; linkid--)
605			if (!ctrl->loop_linkused[linkid])
606				goto found;
607		spin_unlock_bh(&ctrl->loop_linkid_lock);
608		return -1;
609found:
610		if (linkid < 10)
611			dec = 0;
612
613		if (!ctrl->loop_linkused[linkid])
614			ctrl->loop_linkused[linkid] = 1;
615
616		last_linkid = linkid;
617
618		cfpkt_add_trail(pkt, &linkid, 1);
619		spin_unlock_bh(&ctrl->loop_linkid_lock);
620		cfpkt_peek_head(pkt, &linktype, 1);
621		if (linktype ==  CFCTRL_SRV_UTIL) {
622			tmp = 0x01;
623			cfpkt_add_trail(pkt, &tmp, 1);
624			cfpkt_add_trail(pkt, &tmp, 1);
625		}
626		break;
627
628	case CFCTRL_CMD_LINK_DESTROY:
629		spin_lock_bh(&ctrl->loop_linkid_lock);
630		cfpkt_peek_head(pkt, &linkid, 1);
631		ctrl->loop_linkused[linkid] = 0;
632		spin_unlock_bh(&ctrl->loop_linkid_lock);
633		break;
634	default:
635		break;
636	}
637	return 0;
638}
639#endif
640