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Merge tag 'char-misc-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh...
[linux-2.6-block.git] / drivers / hsi / clients / ssi_protocol.c
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dc7bf5d7
SR		 1/*
2 * ssi_protocol.c
3 *
4 * Implementation of the SSI McSAAB improved protocol.
5 *
6 * Copyright (C) 2010 Nokia Corporation. All rights reserved.
7 * Copyright (C) 2013 Sebastian Reichel <sre@kernel.org>
8 *
9 * Contact: Carlos Chinea <carlos.chinea@nokia.com>
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * version 2 as published by the Free Software Foundation.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
23 * 02110-1301 USA
24 */
25
26#include <linux/atomic.h>
27#include <linux/clk.h>
28#include <linux/device.h>
29#include <linux/err.h>
30#include <linux/gpio.h>
31#include <linux/if_ether.h>
32#include <linux/if_arp.h>
33#include <linux/if_phonet.h>
34#include <linux/init.h>
35#include <linux/irq.h>
36#include <linux/list.h>
37#include <linux/module.h>
38#include <linux/netdevice.h>
39#include <linux/notifier.h>
40#include <linux/scatterlist.h>
41#include <linux/skbuff.h>
42#include <linux/slab.h>
43#include <linux/spinlock.h>
44#include <linux/timer.h>
45#include <linux/hsi/hsi.h>
46#include <linux/hsi/ssi_protocol.h>
47
48void ssi_waketest(struct hsi_client *cl, unsigned int enable);
49
50#define SSIP_TXQUEUE_LEN 100
51#define SSIP_MAX_MTU 65535
52#define SSIP_DEFAULT_MTU 4000
53#define PN_MEDIA_SOS 21
54#define SSIP_MIN_PN_HDR 6 /* FIXME: Revisit */
55#define SSIP_WDTOUT 2000 /* FIXME: has to be 500 msecs */
56#define SSIP_KATOUT 15 /* 15 msecs */
57#define SSIP_MAX_CMDS 5 /* Number of pre-allocated commands buffers */
58#define SSIP_BYTES_TO_FRAMES(x) ((((x) - 1) >> 2) + 1)
59#define SSIP_CMT_LOADER_SYNC 0x11223344
60/*
61 * SSI protocol command definitions
62 */
63#define SSIP_COMMAND(data) ((data) >> 28)
64#define SSIP_PAYLOAD(data) ((data) & 0xfffffff)
65/* Commands */
66#define SSIP_SW_BREAK 0
67#define SSIP_BOOTINFO_REQ 1
68#define SSIP_BOOTINFO_RESP 2
69#define SSIP_WAKETEST_RESULT 3
70#define SSIP_START_TRANS 4
71#define SSIP_READY 5
72/* Payloads */
73#define SSIP_DATA_VERSION(data) ((data) & 0xff)
74#define SSIP_LOCAL_VERID 1
75#define SSIP_WAKETEST_OK 0
76#define SSIP_WAKETEST_FAILED 1
77#define SSIP_PDU_LENGTH(data) (((data) >> 8) & 0xffff)
78#define SSIP_MSG_ID(data) ((data) & 0xff)
79/* Generic Command */
80#define SSIP_CMD(cmd, payload) (((cmd) << 28) | ((payload) & 0xfffffff))
81/* Commands for the control channel */
82#define SSIP_BOOTINFO_REQ_CMD(ver) \
83 SSIP_CMD(SSIP_BOOTINFO_REQ, SSIP_DATA_VERSION(ver))
84#define SSIP_BOOTINFO_RESP_CMD(ver) \
85 SSIP_CMD(SSIP_BOOTINFO_RESP, SSIP_DATA_VERSION(ver))
86#define SSIP_START_TRANS_CMD(pdulen, id) \
87 SSIP_CMD(SSIP_START_TRANS, (((pdulen) << 8) | SSIP_MSG_ID(id)))
88#define SSIP_READY_CMD SSIP_CMD(SSIP_READY, 0)
89#define SSIP_SWBREAK_CMD SSIP_CMD(SSIP_SW_BREAK, 0)
90
91/* Main state machine states */
92enum {
93 INIT,
94 HANDSHAKE,
95 ACTIVE,
96};
97
98/* Send state machine states */
99enum {
100 SEND_IDLE,
101 WAIT4READY,
102 SEND_READY,
103 SENDING,
104 SENDING_SWBREAK,
105};
106
107/* Receive state machine states */
108enum {
109 RECV_IDLE,
110 RECV_READY,
111 RECEIVING,
112};
113
114/**
115 * struct ssi_protocol - SSI protocol (McSAAB) data
116 * @main_state: Main state machine
117 * @send_state: TX state machine
118 * @recv_state: RX state machine
119 * @waketest: Flag to follow wake line test
120 * @rxid: RX data id
121 * @txid: TX data id
122 * @txqueue_len: TX queue length
123 * @tx_wd: TX watchdog
124 * @rx_wd: RX watchdog
125 * @keep_alive: Workaround for SSI HW bug
126 * @lock: To serialize access to this struct
127 * @netdev: Phonet network device
128 * @txqueue: TX data queue
129 * @cmdqueue: Queue of free commands
130 * @cl: HSI client own reference
131 * @link: Link for ssip_list
132 * @tx_usecount: Refcount to keep track the slaves that use the wake line
133 * @channel_id_cmd: HSI channel id for command stream
134 * @channel_id_data: HSI channel id for data stream
135 */
136struct ssi_protocol {
137 unsigned int main_state;
138 unsigned int send_state;
139 unsigned int recv_state;
140 unsigned int waketest:1;
141 u8 rxid;
142 u8 txid;
143 unsigned int txqueue_len;
144 struct timer_list tx_wd;
145 struct timer_list rx_wd;
146 struct timer_list keep_alive; /* wake-up workaround */
147 spinlock_t lock;
148 struct net_device *netdev;
149 struct list_head txqueue;
150 struct list_head cmdqueue;
151 struct hsi_client *cl;
152 struct list_head link;
153 atomic_t tx_usecnt;
154 int channel_id_cmd;
155 int channel_id_data;
156};
157
158/* List of ssi protocol instances */
159static LIST_HEAD(ssip_list);
160
161static void ssip_rxcmd_complete(struct hsi_msg *msg);
162
163static inline void ssip_set_cmd(struct hsi_msg *msg, u32 cmd)
164{
165 u32 *data;
166
167 data = sg_virt(msg->sgt.sgl);
168 *data = cmd;
169}
170
171static inline u32 ssip_get_cmd(struct hsi_msg *msg)
172{
173 u32 *data;
174
175 data = sg_virt(msg->sgt.sgl);
176
177 return *data;
178}
179
180static void ssip_skb_to_msg(struct sk_buff *skb, struct hsi_msg *msg)
181{
182 skb_frag_t *frag;
183 struct scatterlist *sg;
184 int i;
185
186 BUG_ON(msg->sgt.nents != (unsigned int)(skb_shinfo(skb)->nr_frags + 1));
187
188 sg = msg->sgt.sgl;
189 sg_set_buf(sg, skb->data, skb_headlen(skb));
190 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
191 sg = sg_next(sg);
192 BUG_ON(!sg);
193 frag = &skb_shinfo(skb)->frags[i];
194 sg_set_page(sg, frag->page.p, frag->size, frag->page_offset);
195 }
196}
197
198static void ssip_free_data(struct hsi_msg *msg)
199{
200 struct sk_buff *skb;
201
202 skb = msg->context;
203 pr_debug("free data: msg %p context %p skb %p\n", msg, msg->context,
204 skb);
205 msg->destructor = NULL;
206 dev_kfree_skb(skb);
207 hsi_free_msg(msg);
208}
209
210static struct hsi_msg *ssip_alloc_data(struct ssi_protocol *ssi,
211 struct sk_buff *skb, gfp_t flags)
212{
213 struct hsi_msg *msg;
214
215 msg = hsi_alloc_msg(skb_shinfo(skb)->nr_frags + 1, flags);
216 if (!msg)
217 return NULL;
218 ssip_skb_to_msg(skb, msg);
219 msg->destructor = ssip_free_data;
220 msg->channel = ssi->channel_id_data;
221 msg->context = skb;
222
223 return msg;
224}
225
226static inline void ssip_release_cmd(struct hsi_msg *msg)
227{
228 struct ssi_protocol *ssi = hsi_client_drvdata(msg->cl);
229
230 dev_dbg(&msg->cl->device, "Release cmd 0x%08x\n", ssip_get_cmd(msg));
231 spin_lock_bh(&ssi->lock);
232 list_add_tail(&msg->link, &ssi->cmdqueue);
233 spin_unlock_bh(&ssi->lock);
234}
235
236static struct hsi_msg *ssip_claim_cmd(struct ssi_protocol *ssi)
237{
238 struct hsi_msg *msg;
239
240 BUG_ON(list_empty(&ssi->cmdqueue));
241
242 spin_lock_bh(&ssi->lock);
243 msg = list_first_entry(&ssi->cmdqueue, struct hsi_msg, link);
244 list_del(&msg->link);
245 spin_unlock_bh(&ssi->lock);
246 msg->destructor = ssip_release_cmd;
247
248 return msg;
249}
250
251static void ssip_free_cmds(struct ssi_protocol *ssi)
252{
253 struct hsi_msg *msg, *tmp;
254
255 list_for_each_entry_safe(msg, tmp, &ssi->cmdqueue, link) {
256 list_del(&msg->link);
257 msg->destructor = NULL;
258 kfree(sg_virt(msg->sgt.sgl));
259 hsi_free_msg(msg);
260 }
261}
262
263static int ssip_alloc_cmds(struct ssi_protocol *ssi)
264{
265 struct hsi_msg *msg;
266 u32 *buf;
267 unsigned int i;
268
269 for (i = 0; i < SSIP_MAX_CMDS; i++) {
270 msg = hsi_alloc_msg(1, GFP_KERNEL);
271 if (!msg)
272 goto out;
273 buf = kmalloc(sizeof(*buf), GFP_KERNEL);
274 if (!buf) {
275 hsi_free_msg(msg);
276 goto out;
277 }
278 sg_init_one(msg->sgt.sgl, buf, sizeof(*buf));
279 msg->channel = ssi->channel_id_cmd;
280 list_add_tail(&msg->link, &ssi->cmdqueue);
281 }
282
283 return 0;
284out:
285 ssip_free_cmds(ssi);
286
287 return -ENOMEM;
288}
289
290static void ssip_set_rxstate(struct ssi_protocol *ssi, unsigned int state)
291{
292 ssi->recv_state = state;
293 switch (state) {
294 case RECV_IDLE:
295 del_timer(&ssi->rx_wd);
296 if (ssi->send_state == SEND_IDLE)
297 del_timer(&ssi->keep_alive);
298 break;
299 case RECV_READY:
300 /* CMT speech workaround */
301 if (atomic_read(&ssi->tx_usecnt))
302 break;
303 /* Otherwise fall through */
304 case RECEIVING:
305 mod_timer(&ssi->keep_alive, jiffies +
306 msecs_to_jiffies(SSIP_KATOUT));
307 mod_timer(&ssi->rx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT));
308 break;
309 default:
310 break;
311 }
312}
313
314static void ssip_set_txstate(struct ssi_protocol *ssi, unsigned int state)
315{
316 ssi->send_state = state;
317 switch (state) {
318 case SEND_IDLE:
319 case SEND_READY:
320 del_timer(&ssi->tx_wd);
321 if (ssi->recv_state == RECV_IDLE)
322 del_timer(&ssi->keep_alive);
323 break;
324 case WAIT4READY:
325 case SENDING:
326 case SENDING_SWBREAK:
327 mod_timer(&ssi->keep_alive,
328 jiffies + msecs_to_jiffies(SSIP_KATOUT));
329 mod_timer(&ssi->tx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT));
330 break;
331 default:
332 break;
333 }
334}
335
336struct hsi_client *ssip_slave_get_master(struct hsi_client *slave)
337{
338 struct hsi_client *master = ERR_PTR(-ENODEV);
339 struct ssi_protocol *ssi;
340
341 list_for_each_entry(ssi, &ssip_list, link)
342 if (slave->device.parent == ssi->cl->device.parent) {
343 master = ssi->cl;
344 break;
345 }
346
347 return master;
348}
349EXPORT_SYMBOL_GPL(ssip_slave_get_master);
350
351int ssip_slave_start_tx(struct hsi_client *master)
352{
353 struct ssi_protocol *ssi = hsi_client_drvdata(master);
354
355 dev_dbg(&master->device, "start TX %d\n", atomic_read(&ssi->tx_usecnt));
356 spin_lock_bh(&ssi->lock);
357 if (ssi->send_state == SEND_IDLE) {
358 ssip_set_txstate(ssi, WAIT4READY);
359 hsi_start_tx(master);
360 }
361 spin_unlock_bh(&ssi->lock);
362 atomic_inc(&ssi->tx_usecnt);
363
364 return 0;
365}
366EXPORT_SYMBOL_GPL(ssip_slave_start_tx);
367
368int ssip_slave_stop_tx(struct hsi_client *master)
369{
370 struct ssi_protocol *ssi = hsi_client_drvdata(master);
371
372 WARN_ON_ONCE(atomic_read(&ssi->tx_usecnt) == 0);
373
374 if (atomic_dec_and_test(&ssi->tx_usecnt)) {
375 spin_lock_bh(&ssi->lock);
376 if ((ssi->send_state == SEND_READY) ||
377 (ssi->send_state == WAIT4READY)) {
378 ssip_set_txstate(ssi, SEND_IDLE);
379 hsi_stop_tx(master);
380 }
381 spin_unlock_bh(&ssi->lock);
382 }
383 dev_dbg(&master->device, "stop TX %d\n", atomic_read(&ssi->tx_usecnt));
384
385 return 0;
386}
387EXPORT_SYMBOL_GPL(ssip_slave_stop_tx);
388
389int ssip_slave_running(struct hsi_client *master)
390{
391 struct ssi_protocol *ssi = hsi_client_drvdata(master);
392 return netif_running(ssi->netdev);
393}
394EXPORT_SYMBOL_GPL(ssip_slave_running);
395
396static void ssip_reset(struct hsi_client *cl)
397{
398 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
399 struct list_head *head, *tmp;
400 struct hsi_msg *msg;
401
402 if (netif_running(ssi->netdev))
403 netif_carrier_off(ssi->netdev);
404 hsi_flush(cl);
405 spin_lock_bh(&ssi->lock);
406 if (ssi->send_state != SEND_IDLE)
407 hsi_stop_tx(cl);
408 if (ssi->waketest)
409 ssi_waketest(cl, 0);
410 del_timer(&ssi->rx_wd);
411 del_timer(&ssi->tx_wd);
412 del_timer(&ssi->keep_alive);
413 ssi->main_state = 0;
414 ssi->send_state = 0;
415 ssi->recv_state = 0;
416 ssi->waketest = 0;
417 ssi->rxid = 0;
418 ssi->txid = 0;
419 list_for_each_safe(head, tmp, &ssi->txqueue) {
420 msg = list_entry(head, struct hsi_msg, link);
421 dev_dbg(&cl->device, "Pending TX data\n");
422 list_del(head);
423 ssip_free_data(msg);
424 }
425 ssi->txqueue_len = 0;
426 spin_unlock_bh(&ssi->lock);
427}
428
429static void ssip_dump_state(struct hsi_client *cl)
430{
431 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
432 struct hsi_msg *msg;
433
434 spin_lock_bh(&ssi->lock);
435 dev_err(&cl->device, "Main state: %d\n", ssi->main_state);
436 dev_err(&cl->device, "Recv state: %d\n", ssi->recv_state);
437 dev_err(&cl->device, "Send state: %d\n", ssi->send_state);
438 dev_err(&cl->device, "CMT %s\n", (ssi->main_state == ACTIVE) ?
439 "Online" : "Offline");
440 dev_err(&cl->device, "Wake test %d\n", ssi->waketest);
441 dev_err(&cl->device, "Data RX id: %d\n", ssi->rxid);
442 dev_err(&cl->device, "Data TX id: %d\n", ssi->txid);
443
444 list_for_each_entry(msg, &ssi->txqueue, link)
445 dev_err(&cl->device, "pending TX data (%p)\n", msg);
446 spin_unlock_bh(&ssi->lock);
447}
448
449static void ssip_error(struct hsi_client *cl)
450{
451 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
452 struct hsi_msg *msg;
453
454 ssip_dump_state(cl);
455 ssip_reset(cl);
456 msg = ssip_claim_cmd(ssi);
457 msg->complete = ssip_rxcmd_complete;
458 hsi_async_read(cl, msg);
459}
460
461static void ssip_keep_alive(unsigned long data)
462{
463 struct hsi_client *cl = (struct hsi_client *)data;
464 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
465
466 dev_dbg(&cl->device, "Keep alive kick in: m(%d) r(%d) s(%d)\n",
467 ssi->main_state, ssi->recv_state, ssi->send_state);
468
469 spin_lock(&ssi->lock);
470 if (ssi->recv_state == RECV_IDLE)
471 switch (ssi->send_state) {
472 case SEND_READY:
473 if (atomic_read(&ssi->tx_usecnt) == 0)
474 break;
475 /*
476 * Fall through. Workaround for cmt-speech
477 * in that case we relay on audio timers.
478 */
479 case SEND_IDLE:
480 spin_unlock(&ssi->lock);
481 return;
482 }
483 mod_timer(&ssi->keep_alive, jiffies + msecs_to_jiffies(SSIP_KATOUT));
484 spin_unlock(&ssi->lock);
485}
486
487static void ssip_wd(unsigned long data)
488{
489 struct hsi_client *cl = (struct hsi_client *)data;
490
491 dev_err(&cl->device, "Watchdog trigerred\n");
492 ssip_error(cl);
493}
494
495static void ssip_send_bootinfo_req_cmd(struct hsi_client *cl)
496{
497 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
498 struct hsi_msg *msg;
499
500 dev_dbg(&cl->device, "Issuing BOOT INFO REQ command\n");
501 msg = ssip_claim_cmd(ssi);
502 ssip_set_cmd(msg, SSIP_BOOTINFO_REQ_CMD(SSIP_LOCAL_VERID));
503 msg->complete = ssip_release_cmd;
504 hsi_async_write(cl, msg);
505 dev_dbg(&cl->device, "Issuing RX command\n");
506 msg = ssip_claim_cmd(ssi);
507 msg->complete = ssip_rxcmd_complete;
508 hsi_async_read(cl, msg);
509}
510
511static void ssip_start_rx(struct hsi_client *cl)
512{
513 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
514 struct hsi_msg *msg;
515
516 dev_dbg(&cl->device, "RX start M(%d) R(%d)\n", ssi->main_state,
517 ssi->recv_state);
518 spin_lock(&ssi->lock);
519 /*
520 * We can have two UP events in a row due to a short low
521 * high transition. Therefore we need to ignore the sencond UP event.
522 */
523 if ((ssi->main_state != ACTIVE) || (ssi->recv_state == RECV_READY)) {
87d99063 524 spin_unlock(&ssi->lock);
dc7bf5d7
SR		 525 return;
526 }
527 ssip_set_rxstate(ssi, RECV_READY);
528 spin_unlock(&ssi->lock);
529
530 msg = ssip_claim_cmd(ssi);
531 ssip_set_cmd(msg, SSIP_READY_CMD);
532 msg->complete = ssip_release_cmd;
533 dev_dbg(&cl->device, "Send READY\n");
534 hsi_async_write(cl, msg);
535}
536
537static void ssip_stop_rx(struct hsi_client *cl)
538{
539 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
540
541 dev_dbg(&cl->device, "RX stop M(%d)\n", ssi->main_state);
542 spin_lock(&ssi->lock);
543 if (likely(ssi->main_state == ACTIVE))
544 ssip_set_rxstate(ssi, RECV_IDLE);
545 spin_unlock(&ssi->lock);
546}
547
548static void ssip_free_strans(struct hsi_msg *msg)
549{
550 ssip_free_data(msg->context);
551 ssip_release_cmd(msg);
552}
553
554static void ssip_strans_complete(struct hsi_msg *msg)
555{
556 struct hsi_client *cl = msg->cl;
557 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
558 struct hsi_msg *data;
559
560 data = msg->context;
561 ssip_release_cmd(msg);
562 spin_lock(&ssi->lock);
563 ssip_set_txstate(ssi, SENDING);
564 spin_unlock(&ssi->lock);
565 hsi_async_write(cl, data);
566}
567
568static int ssip_xmit(struct hsi_client *cl)
569{
570 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
571 struct hsi_msg *msg, *dmsg;
572 struct sk_buff *skb;
573
574 spin_lock_bh(&ssi->lock);
575 if (list_empty(&ssi->txqueue)) {
576 spin_unlock_bh(&ssi->lock);
577 return 0;
578 }
579 dmsg = list_first_entry(&ssi->txqueue, struct hsi_msg, link);
580 list_del(&dmsg->link);
581 ssi->txqueue_len--;
582 spin_unlock_bh(&ssi->lock);
583
584 msg = ssip_claim_cmd(ssi);
585 skb = dmsg->context;
586 msg->context = dmsg;
587 msg->complete = ssip_strans_complete;
588 msg->destructor = ssip_free_strans;
589
590 spin_lock_bh(&ssi->lock);
591 ssip_set_cmd(msg, SSIP_START_TRANS_CMD(SSIP_BYTES_TO_FRAMES(skb->len),
592 ssi->txid));
593 ssi->txid++;
594 ssip_set_txstate(ssi, SENDING);
595 spin_unlock_bh(&ssi->lock);
596
597 dev_dbg(&cl->device, "Send STRANS (%d frames)\n",
598 SSIP_BYTES_TO_FRAMES(skb->len));
599
600 return hsi_async_write(cl, msg);
601}
602
603/* In soft IRQ context */
604static void ssip_pn_rx(struct sk_buff *skb)
605{
606 struct net_device *dev = skb->dev;
607
608 if (unlikely(!netif_running(dev))) {
609 dev_dbg(&dev->dev, "Drop RX packet\n");
610 dev->stats.rx_dropped++;
611 dev_kfree_skb(skb);
612 return;
613 }
614 if (unlikely(!pskb_may_pull(skb, SSIP_MIN_PN_HDR))) {
615 dev_dbg(&dev->dev, "Error drop RX packet\n");
616 dev->stats.rx_errors++;
617 dev->stats.rx_length_errors++;
618 dev_kfree_skb(skb);
619 return;
620 }
621 dev->stats.rx_packets++;
622 dev->stats.rx_bytes += skb->len;
623
624 /* length field is exchanged in network byte order */
625 ((u16 *)skb->data)[2] = ntohs(((u16 *)skb->data)[2]);
626 dev_dbg(&dev->dev, "RX length fixed (%04x -> %u)\n",
627 ((u16 *)skb->data)[2], ntohs(((u16 *)skb->data)[2]));
628
629 skb->protocol = htons(ETH_P_PHONET);
630 skb_reset_mac_header(skb);
631 __skb_pull(skb, 1);
632 netif_rx(skb);
633}
634
635static void ssip_rx_data_complete(struct hsi_msg *msg)
636{
637 struct hsi_client *cl = msg->cl;
638 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
639 struct sk_buff *skb;
640
641 if (msg->status == HSI_STATUS_ERROR) {
642 dev_err(&cl->device, "RX data error\n");
643 ssip_free_data(msg);
644 ssip_error(cl);
645 return;
646 }
647 del_timer(&ssi->rx_wd); /* FIXME: Revisit */
648 skb = msg->context;
649 ssip_pn_rx(skb);
650 hsi_free_msg(msg);
651}
652
653static void ssip_rx_bootinforeq(struct hsi_client *cl, u32 cmd)
654{
655 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
656 struct hsi_msg *msg;
657
658 /* Workaroud: Ignore CMT Loader message leftover */
659 if (cmd == SSIP_CMT_LOADER_SYNC)
660 return;
661
662 switch (ssi->main_state) {
663 case ACTIVE:
664 dev_err(&cl->device, "Boot info req on active state\n");
665 ssip_error(cl);
666 /* Fall through */
667 case INIT:
87d99063 668 case HANDSHAKE:
dc7bf5d7
SR		 669 spin_lock(&ssi->lock);
670 ssi->main_state = HANDSHAKE;
671 if (!ssi->waketest) {
672 ssi->waketest = 1;
673 ssi_waketest(cl, 1); /* FIXME: To be removed */
674 }
675 /* Start boot handshake watchdog */
676 mod_timer(&ssi->tx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT));
677 spin_unlock(&ssi->lock);
678 dev_dbg(&cl->device, "Send BOOTINFO_RESP\n");
679 if (SSIP_DATA_VERSION(cmd) != SSIP_LOCAL_VERID)
680 dev_warn(&cl->device, "boot info req verid mismatch\n");
681 msg = ssip_claim_cmd(ssi);
682 ssip_set_cmd(msg, SSIP_BOOTINFO_RESP_CMD(SSIP_LOCAL_VERID));
683 msg->complete = ssip_release_cmd;
684 hsi_async_write(cl, msg);
685 break;
dc7bf5d7
SR		 686 default:
687 dev_dbg(&cl->device, "Wrong state M(%d)\n", ssi->main_state);
688 break;
689 }
690}
691
692static void ssip_rx_bootinforesp(struct hsi_client *cl, u32 cmd)
693{
694 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
695
696 if (SSIP_DATA_VERSION(cmd) != SSIP_LOCAL_VERID)
697 dev_warn(&cl->device, "boot info resp verid mismatch\n");
698
699 spin_lock(&ssi->lock);
700 if (ssi->main_state != ACTIVE)
701 /* Use tx_wd as a boot watchdog in non ACTIVE state */
702 mod_timer(&ssi->tx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT));
703 else
704 dev_dbg(&cl->device, "boot info resp ignored M(%d)\n",
705 ssi->main_state);
706 spin_unlock(&ssi->lock);
707}
708
709static void ssip_rx_waketest(struct hsi_client *cl, u32 cmd)
710{
711 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
712 unsigned int wkres = SSIP_PAYLOAD(cmd);
713
714 spin_lock(&ssi->lock);
715 if (ssi->main_state != HANDSHAKE) {
716 dev_dbg(&cl->device, "wake lines test ignored M(%d)\n",
717 ssi->main_state);
718 spin_unlock(&ssi->lock);
719 return;
720 }
721 if (ssi->waketest) {
722 ssi->waketest = 0;
723 ssi_waketest(cl, 0); /* FIXME: To be removed */
724 }
725 ssi->main_state = ACTIVE;
726 del_timer(&ssi->tx_wd); /* Stop boot handshake timer */
727 spin_unlock(&ssi->lock);
728
729 dev_notice(&cl->device, "WAKELINES TEST %s\n",
730 wkres & SSIP_WAKETEST_FAILED ? "FAILED" : "OK");
731 if (wkres & SSIP_WAKETEST_FAILED) {
732 ssip_error(cl);
733 return;
734 }
735 dev_dbg(&cl->device, "CMT is ONLINE\n");
736 netif_wake_queue(ssi->netdev);
737 netif_carrier_on(ssi->netdev);
738}
739
740static void ssip_rx_ready(struct hsi_client *cl)
741{
742 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
743
744 spin_lock(&ssi->lock);
745 if (unlikely(ssi->main_state != ACTIVE)) {
746 dev_dbg(&cl->device, "READY on wrong state: S(%d) M(%d)\n",
747 ssi->send_state, ssi->main_state);
748 spin_unlock(&ssi->lock);
749 return;
750 }
751 if (ssi->send_state != WAIT4READY) {
752 dev_dbg(&cl->device, "Ignore spurious READY command\n");
753 spin_unlock(&ssi->lock);
754 return;
755 }
756 ssip_set_txstate(ssi, SEND_READY);
757 spin_unlock(&ssi->lock);
758 ssip_xmit(cl);
759}
760
761static void ssip_rx_strans(struct hsi_client *cl, u32 cmd)
762{
763 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
764 struct sk_buff *skb;
765 struct hsi_msg *msg;
766 int len = SSIP_PDU_LENGTH(cmd);
767
768 dev_dbg(&cl->device, "RX strans: %d frames\n", len);
769 spin_lock(&ssi->lock);
770 if (unlikely(ssi->main_state != ACTIVE)) {
771 dev_err(&cl->device, "START TRANS wrong state: S(%d) M(%d)\n",
772 ssi->send_state, ssi->main_state);
773 spin_unlock(&ssi->lock);
774 return;
775 }
776 ssip_set_rxstate(ssi, RECEIVING);
777 if (unlikely(SSIP_MSG_ID(cmd) != ssi->rxid)) {
c616ac28 778 dev_err(&cl->device, "START TRANS id %d expected %d\n",
dc7bf5d7
SR		 779 SSIP_MSG_ID(cmd), ssi->rxid);
780 spin_unlock(&ssi->lock);
781 goto out1;
782 }
783 ssi->rxid++;
784 spin_unlock(&ssi->lock);
785 skb = netdev_alloc_skb(ssi->netdev, len * 4);
786 if (unlikely(!skb)) {
787 dev_err(&cl->device, "No memory for rx skb\n");
788 goto out1;
789 }
790 skb->dev = ssi->netdev;
791 skb_put(skb, len * 4);
792 msg = ssip_alloc_data(ssi, skb, GFP_ATOMIC);
793 if (unlikely(!msg)) {
794 dev_err(&cl->device, "No memory for RX data msg\n");
795 goto out2;
796 }
797 msg->complete = ssip_rx_data_complete;
798 hsi_async_read(cl, msg);
799
800 return;
801out2:
802 dev_kfree_skb(skb);
803out1:
804 ssip_error(cl);
805}
806
807static void ssip_rxcmd_complete(struct hsi_msg *msg)
808{
809 struct hsi_client *cl = msg->cl;
810 u32 cmd = ssip_get_cmd(msg);
811 unsigned int cmdid = SSIP_COMMAND(cmd);
812
813 if (msg->status == HSI_STATUS_ERROR) {
814 dev_err(&cl->device, "RX error detected\n");
815 ssip_release_cmd(msg);
816 ssip_error(cl);
817 return;
818 }
819 hsi_async_read(cl, msg);
820 dev_dbg(&cl->device, "RX cmd: 0x%08x\n", cmd);
821 switch (cmdid) {
822 case SSIP_SW_BREAK:
823 /* Ignored */
824 break;
825 case SSIP_BOOTINFO_REQ:
826 ssip_rx_bootinforeq(cl, cmd);
827 break;
828 case SSIP_BOOTINFO_RESP:
829 ssip_rx_bootinforesp(cl, cmd);
830 break;
831 case SSIP_WAKETEST_RESULT:
832 ssip_rx_waketest(cl, cmd);
833 break;
834 case SSIP_START_TRANS:
835 ssip_rx_strans(cl, cmd);
836 break;
837 case SSIP_READY:
838 ssip_rx_ready(cl);
839 break;
840 default:
841 dev_warn(&cl->device, "command 0x%08x not supported\n", cmd);
842 break;
843 }
844}
845
846static void ssip_swbreak_complete(struct hsi_msg *msg)
847{
848 struct hsi_client *cl = msg->cl;
849 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
850
851 ssip_release_cmd(msg);
852 spin_lock(&ssi->lock);
853 if (list_empty(&ssi->txqueue)) {
854 if (atomic_read(&ssi->tx_usecnt)) {
855 ssip_set_txstate(ssi, SEND_READY);
856 } else {
857 ssip_set_txstate(ssi, SEND_IDLE);
858 hsi_stop_tx(cl);
859 }
860 spin_unlock(&ssi->lock);
861 } else {
862 spin_unlock(&ssi->lock);
863 ssip_xmit(cl);
864 }
865 netif_wake_queue(ssi->netdev);
866}
867
868static void ssip_tx_data_complete(struct hsi_msg *msg)
869{
870 struct hsi_client *cl = msg->cl;
871 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
872 struct hsi_msg *cmsg;
873
874 if (msg->status == HSI_STATUS_ERROR) {
875 dev_err(&cl->device, "TX data error\n");
876 ssip_error(cl);
877 goto out;
878 }
879 spin_lock(&ssi->lock);
880 if (list_empty(&ssi->txqueue)) {
881 ssip_set_txstate(ssi, SENDING_SWBREAK);
882 spin_unlock(&ssi->lock);
883 cmsg = ssip_claim_cmd(ssi);
884 ssip_set_cmd(cmsg, SSIP_SWBREAK_CMD);
885 cmsg->complete = ssip_swbreak_complete;
886 dev_dbg(&cl->device, "Send SWBREAK\n");
887 hsi_async_write(cl, cmsg);
888 } else {
889 spin_unlock(&ssi->lock);
890 ssip_xmit(cl);
891 }
892out:
893 ssip_free_data(msg);
894}
895
0a0ea07d 896static void ssip_port_event(struct hsi_client *cl, unsigned long event)
dc7bf5d7
SR		 897{
898 switch (event) {
899 case HSI_EVENT_START_RX:
900 ssip_start_rx(cl);
901 break;
902 case HSI_EVENT_STOP_RX:
903 ssip_stop_rx(cl);
904 break;
905 default:
906 return;
907 }
908}
909
910static int ssip_pn_open(struct net_device *dev)
911{
912 struct hsi_client *cl = to_hsi_client(dev->dev.parent);
913 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
914 int err;
915
916 err = hsi_claim_port(cl, 1);
917 if (err < 0) {
918 dev_err(&cl->device, "SSI port already claimed\n");
919 return err;
920 }
921 err = hsi_register_port_event(cl, ssip_port_event);
922 if (err < 0) {
923 dev_err(&cl->device, "Register HSI port event failed (%d)\n",
924 err);
925 return err;
926 }
927 dev_dbg(&cl->device, "Configuring SSI port\n");
928 hsi_setup(cl);
929 spin_lock_bh(&ssi->lock);
930 if (!ssi->waketest) {
931 ssi->waketest = 1;
932 ssi_waketest(cl, 1); /* FIXME: To be removed */
933 }
87d99063 934 ssi->main_state = HANDSHAKE;
dc7bf5d7
SR		 935 spin_unlock_bh(&ssi->lock);
936
87d99063
SR		 937 ssip_send_bootinfo_req_cmd(cl);
938
dc7bf5d7
SR		 939 return 0;
940}
941
942static int ssip_pn_stop(struct net_device *dev)
943{
944 struct hsi_client *cl = to_hsi_client(dev->dev.parent);
945
946 ssip_reset(cl);
947 hsi_unregister_port_event(cl);
948 hsi_release_port(cl);
949
950 return 0;
951}
952
953static int ssip_pn_set_mtu(struct net_device *dev, int new_mtu)
954{
955 if (new_mtu > SSIP_MAX_MTU || new_mtu < PHONET_MIN_MTU)
956 return -EINVAL;
957 dev->mtu = new_mtu;
958
959 return 0;
960}
961
962static int ssip_pn_xmit(struct sk_buff *skb, struct net_device *dev)
963{
964 struct hsi_client *cl = to_hsi_client(dev->dev.parent);
965 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
966 struct hsi_msg *msg;
967
968 if ((skb->protocol != htons(ETH_P_PHONET)) ||
969 (skb->len < SSIP_MIN_PN_HDR))
970 goto drop;
971 /* Pad to 32-bits - FIXME: Revisit*/
972 if ((skb->len & 3) && skb_pad(skb, 4 - (skb->len & 3)))
973 goto drop;
974
975 /*
976 * Modem sends Phonet messages over SSI with its own endianess...
977 * Assume that modem has the same endianess as we do.
978 */
979 if (skb_cow_head(skb, 0))
980 goto drop;
981
982 /* length field is exchanged in network byte order */
983 ((u16 *)skb->data)[2] = htons(((u16 *)skb->data)[2]);
984
985 msg = ssip_alloc_data(ssi, skb, GFP_ATOMIC);
986 if (!msg) {
987 dev_dbg(&cl->device, "Dropping tx data: No memory\n");
988 goto drop;
989 }
990 msg->complete = ssip_tx_data_complete;
991
992 spin_lock_bh(&ssi->lock);
993 if (unlikely(ssi->main_state != ACTIVE)) {
994 spin_unlock_bh(&ssi->lock);
995 dev_dbg(&cl->device, "Dropping tx data: CMT is OFFLINE\n");
996 goto drop2;
997 }
998 list_add_tail(&msg->link, &ssi->txqueue);
999 ssi->txqueue_len++;
1000 if (dev->tx_queue_len < ssi->txqueue_len) {
1001 dev_info(&cl->device, "TX queue full %d\n", ssi->txqueue_len);
1002 netif_stop_queue(dev);
1003 }
1004 if (ssi->send_state == SEND_IDLE) {
1005 ssip_set_txstate(ssi, WAIT4READY);
1006 spin_unlock_bh(&ssi->lock);
1007 dev_dbg(&cl->device, "Start TX qlen %d\n", ssi->txqueue_len);
1008 hsi_start_tx(cl);
1009 } else if (ssi->send_state == SEND_READY) {
1010 /* Needed for cmt-speech workaround */
1011 dev_dbg(&cl->device, "Start TX on SEND READY qlen %d\n",
1012 ssi->txqueue_len);
1013 spin_unlock_bh(&ssi->lock);
1014 ssip_xmit(cl);
1015 } else {
1016 spin_unlock_bh(&ssi->lock);
1017 }
1018 dev->stats.tx_packets++;
1019 dev->stats.tx_bytes += skb->len;
1020
1021 return 0;
1022drop2:
1023 hsi_free_msg(msg);
1024drop:
1025 dev->stats.tx_dropped++;
1026 dev_kfree_skb(skb);
1027
1028 return 0;
1029}
1030
1031/* CMT reset event handler */
1032void ssip_reset_event(struct hsi_client *master)
1033{
1034 struct ssi_protocol *ssi = hsi_client_drvdata(master);
1035 dev_err(&ssi->cl->device, "CMT reset detected!\n");
1036 ssip_error(ssi->cl);
1037}
1038EXPORT_SYMBOL_GPL(ssip_reset_event);
1039
1040static const struct net_device_ops ssip_pn_ops = {
1041 .ndo_open = ssip_pn_open,
1042 .ndo_stop = ssip_pn_stop,
1043 .ndo_start_xmit = ssip_pn_xmit,
1044 .ndo_change_mtu = ssip_pn_set_mtu,
1045};
1046
1047static void ssip_pn_setup(struct net_device *dev)
1048{
1049 dev->features = 0;
1050 dev->netdev_ops = &ssip_pn_ops;
1051 dev->type = ARPHRD_PHONET;
1052 dev->flags = IFF_POINTOPOINT | IFF_NOARP;
1053 dev->mtu = SSIP_DEFAULT_MTU;
1054 dev->hard_header_len = 1;
1055 dev->dev_addr[0] = PN_MEDIA_SOS;
1056 dev->addr_len = 1;
1057 dev->tx_queue_len = SSIP_TXQUEUE_LEN;
1058
1059 dev->destructor = free_netdev;
1060 dev->header_ops = &phonet_header_ops;
1061}
1062
1063static int ssi_protocol_probe(struct device *dev)
1064{
1065 static const char ifname[] = "phonet%d";
1066 struct hsi_client *cl = to_hsi_client(dev);
1067 struct ssi_protocol *ssi;
1068 int err;
1069
1070 ssi = kzalloc(sizeof(*ssi), GFP_KERNEL);
1071 if (!ssi) {
1072 dev_err(dev, "No memory for ssi protocol\n");
1073 return -ENOMEM;
1074 }
1075
1076 spin_lock_init(&ssi->lock);
1077 init_timer_deferrable(&ssi->rx_wd);
1078 init_timer_deferrable(&ssi->tx_wd);
1079 init_timer(&ssi->keep_alive);
1080 ssi->rx_wd.data = (unsigned long)cl;
1081 ssi->rx_wd.function = ssip_wd;
1082 ssi->tx_wd.data = (unsigned long)cl;
1083 ssi->tx_wd.function = ssip_wd;
1084 ssi->keep_alive.data = (unsigned long)cl;
1085 ssi->keep_alive.function = ssip_keep_alive;
1086 INIT_LIST_HEAD(&ssi->txqueue);
1087 INIT_LIST_HEAD(&ssi->cmdqueue);
1088 atomic_set(&ssi->tx_usecnt, 0);
1089 hsi_client_set_drvdata(cl, ssi);
1090 ssi->cl = cl;
1091
1092 ssi->channel_id_cmd = hsi_get_channel_id_by_name(cl, "mcsaab-control");
1093 if (ssi->channel_id_cmd < 0) {
1094 err = ssi->channel_id_cmd;
1095 dev_err(dev, "Could not get cmd channel (%d)\n", err);
1096 goto out;
1097 }
1098
1099 ssi->channel_id_data = hsi_get_channel_id_by_name(cl, "mcsaab-data");
1100 if (ssi->channel_id_data < 0) {
1101 err = ssi->channel_id_data;
1102 dev_err(dev, "Could not get data channel (%d)\n", err);
1103 goto out;
1104 }
1105
1106 err = ssip_alloc_cmds(ssi);
1107 if (err < 0) {
1108 dev_err(dev, "No memory for commands\n");
1109 goto out;
1110 }
1111
c835a677 1112 ssi->netdev = alloc_netdev(0, ifname, NET_NAME_UNKNOWN, ssip_pn_setup);
dc7bf5d7
SR		 1113 if (!ssi->netdev) {
1114 dev_err(dev, "No memory for netdev\n");
1115 err = -ENOMEM;
1116 goto out1;
1117 }
1118
1119 SET_NETDEV_DEV(ssi->netdev, dev);
1120 netif_carrier_off(ssi->netdev);
1121 err = register_netdev(ssi->netdev);
1122 if (err < 0) {
1123 dev_err(dev, "Register netdev failed (%d)\n", err);
1124 goto out2;
1125 }
1126
1127 list_add(&ssi->link, &ssip_list);
1128
1129 dev_dbg(dev, "channel configuration: cmd=%d, data=%d\n",
1130 ssi->channel_id_cmd, ssi->channel_id_data);
1131
1132 return 0;
1133out2:
1134 free_netdev(ssi->netdev);
1135out1:
1136 ssip_free_cmds(ssi);
1137out:
1138 kfree(ssi);
1139
1140 return err;
1141}
1142
1143static int ssi_protocol_remove(struct device *dev)
1144{
1145 struct hsi_client *cl = to_hsi_client(dev);
1146 struct ssi_protocol *ssi = hsi_client_drvdata(cl);
1147
1148 list_del(&ssi->link);
1149 unregister_netdev(ssi->netdev);
1150 ssip_free_cmds(ssi);
1151 hsi_client_set_drvdata(cl, NULL);
1152 kfree(ssi);
1153
1154 return 0;
1155}
1156
1157static struct hsi_client_driver ssip_driver = {
1158 .driver = {
1159 .name = "ssi-protocol",
1160 .owner = THIS_MODULE,
1161 .probe = ssi_protocol_probe,
1162 .remove = ssi_protocol_remove,
1163 },
1164};
1165
1166static int __init ssip_init(void)
1167{
1168 pr_info("SSI protocol aka McSAAB added\n");
1169
1170 return hsi_register_client_driver(&ssip_driver);
1171}
1172module_init(ssip_init);
1173
1174static void __exit ssip_exit(void)
1175{
1176 hsi_unregister_client_driver(&ssip_driver);
1177 pr_info("SSI protocol driver removed\n");
1178}
1179module_exit(ssip_exit);
1180
1181MODULE_ALIAS("hsi:ssi-protocol");
1182MODULE_AUTHOR("Carlos Chinea <carlos.chinea@nokia.com>");
1183MODULE_AUTHOR("Remi Denis-Courmont <remi.denis-courmont@nokia.com>");
1184MODULE_DESCRIPTION("SSI protocol improved aka McSAAB");
1185MODULE_LICENSE("GPL");
Linux 6.x block layer and io_uring tree(s)