1/*
2 * Copyright (c) 2012 GCT Semiconductor, Inc. All rights reserved.
3 *
4 * This software is licensed under the terms of the GNU General Public
5 * License version 2, as published by the Free Software Foundation, and
6 * may be copied, distributed, and modified under those terms.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 */
13
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/kernel.h>
17
18#include <linux/mmc/core.h>
19#include <linux/mmc/card.h>
20#include <linux/mmc/sdio_func.h>
21#include <linux/mmc/sdio_ids.h>
22
23#include "gdm_sdio.h"
24#include "gdm_wimax.h"
25#include "sdio_boot.h"
26#include "hci.h"
27
28#define TYPE_A_HEADER_SIZE	4
29#define TYPE_A_LOOKAHEAD_SIZE	16
30
31#define MAX_NR_RX_BUF	4
32
33#define SDU_TX_BUF_SIZE	2048
34#define TX_BUF_SIZE	2048
35#define TX_CHUNK_SIZE	(2048 - TYPE_A_HEADER_SIZE)
36#define RX_BUF_SIZE	(25*1024)
37
38#define TX_HZ		2000
39#define TX_INTERVAL	(1000000/TX_HZ)
40
41static struct sdio_tx *alloc_tx_struct(struct tx_cxt *tx)
42{
43	struct sdio_tx *t = kzalloc(sizeof(*t), GFP_ATOMIC);
44
45	if (!t)
46		return NULL;
47
48	t->buf = kmalloc(TX_BUF_SIZE, GFP_ATOMIC);
49	if (!t->buf) {
50		kfree(t);
51		return NULL;
52	}
53
54	t->tx_cxt = tx;
55
56	return t;
57}
58
59static void free_tx_struct(struct sdio_tx *t)
60{
61	if (t) {
62		kfree(t->buf);
63		kfree(t);
64	}
65}
66
67static struct sdio_rx *alloc_rx_struct(struct rx_cxt *rx)
68{
69	struct sdio_rx *r = kzalloc(sizeof(*r), GFP_ATOMIC);
70
71	if (r)
72		r->rx_cxt = rx;
73
74	return r;
75}
76
77static void free_rx_struct(struct sdio_rx *r)
78{
79	kfree(r);
80}
81
82/* Before this function is called, spin lock should be locked. */
83static struct sdio_tx *get_tx_struct(struct tx_cxt *tx, int *no_spc)
84{
85	struct sdio_tx *t;
86
87	if (list_empty(&tx->free_list))
88		return NULL;
89
90	t = list_entry(tx->free_list.prev, struct sdio_tx, list);
91	list_del(&t->list);
92
93	*no_spc = list_empty(&tx->free_list) ? 1 : 0;
94
95	return t;
96}
97
98/* Before this function is called, spin lock should be locked. */
99static void put_tx_struct(struct tx_cxt *tx, struct sdio_tx *t)
100{
101	list_add_tail(&t->list, &tx->free_list);
102}
103
104/* Before this function is called, spin lock should be locked. */
105static struct sdio_rx *get_rx_struct(struct rx_cxt *rx)
106{
107	struct sdio_rx *r;
108
109	if (list_empty(&rx->free_list))
110		return NULL;
111
112	r = list_entry(rx->free_list.prev, struct sdio_rx, list);
113	list_del(&r->list);
114
115	return r;
116}
117
118/* Before this function is called, spin lock should be locked. */
119static void put_rx_struct(struct rx_cxt *rx, struct sdio_rx *r)
120{
121	list_add_tail(&r->list, &rx->free_list);
122}
123
124static void release_sdio(struct sdiowm_dev *sdev)
125{
126	struct tx_cxt	*tx = &sdev->tx;
127	struct rx_cxt	*rx = &sdev->rx;
128	struct sdio_tx	*t, *t_next;
129	struct sdio_rx	*r, *r_next;
130
131	kfree(tx->sdu_buf);
132
133	list_for_each_entry_safe(t, t_next, &tx->free_list, list) {
134		list_del(&t->list);
135		free_tx_struct(t);
136	}
137
138	list_for_each_entry_safe(t, t_next, &tx->sdu_list, list) {
139		list_del(&t->list);
140		free_tx_struct(t);
141	}
142
143	list_for_each_entry_safe(t, t_next, &tx->hci_list, list) {
144		list_del(&t->list);
145		free_tx_struct(t);
146	}
147
148	kfree(rx->rx_buf);
149
150	list_for_each_entry_safe(r, r_next, &rx->free_list, list) {
151		list_del(&r->list);
152		free_rx_struct(r);
153	}
154
155	list_for_each_entry_safe(r, r_next, &rx->req_list, list) {
156		list_del(&r->list);
157		free_rx_struct(r);
158	}
159}
160
161static int init_sdio(struct sdiowm_dev *sdev)
162{
163	int ret = 0, i;
164	struct tx_cxt *tx = &sdev->tx;
165	struct rx_cxt *rx = &sdev->rx;
166	struct sdio_tx *t;
167	struct sdio_rx *r;
168
169	INIT_LIST_HEAD(&tx->free_list);
170	INIT_LIST_HEAD(&tx->sdu_list);
171	INIT_LIST_HEAD(&tx->hci_list);
172
173	spin_lock_init(&tx->lock);
174
175	tx->sdu_buf = kmalloc(SDU_TX_BUF_SIZE, GFP_KERNEL);
176	if (tx->sdu_buf == NULL)
177		goto fail;
178
179	for (i = 0; i < MAX_NR_SDU_BUF; i++) {
180		t = alloc_tx_struct(tx);
181		if (t == NULL) {
182			ret = -ENOMEM;
183			goto fail;
184		}
185		list_add(&t->list, &tx->free_list);
186	}
187
188	INIT_LIST_HEAD(&rx->free_list);
189	INIT_LIST_HEAD(&rx->req_list);
190
191	spin_lock_init(&rx->lock);
192
193	for (i = 0; i < MAX_NR_RX_BUF; i++) {
194		r = alloc_rx_struct(rx);
195		if (r == NULL) {
196			ret = -ENOMEM;
197			goto fail;
198		}
199		list_add(&r->list, &rx->free_list);
200	}
201
202	rx->rx_buf = kmalloc(RX_BUF_SIZE, GFP_KERNEL);
203	if (rx->rx_buf == NULL)
204		goto fail;
205
206	return 0;
207
208fail:
209	release_sdio(sdev);
210	return ret;
211}
212
213static void send_sdio_pkt(struct sdio_func *func, u8 *data, int len)
214{
215	int n, blocks, ret, remain;
216
217	sdio_claim_host(func);
218
219	blocks = len / func->cur_blksize;
220	n = blocks * func->cur_blksize;
221	if (blocks) {
222		ret = sdio_memcpy_toio(func, 0, data, n);
223		if (ret < 0) {
224			if (ret != -ENOMEDIUM)
225				dev_err(&func->dev,
226					"gdmwms:  error: ret = %d\n", ret);
227			goto end_io;
228		}
229	}
230
231	remain = len - n;
232	remain = (remain + 3) & ~3;
233
234	if (remain) {
235		ret = sdio_memcpy_toio(func, 0, data + n, remain);
236		if (ret < 0) {
237			if (ret != -ENOMEDIUM)
238				dev_err(&func->dev,
239					"gdmwms:  error: ret = %d\n", ret);
240			goto end_io;
241		}
242	}
243
244end_io:
245	sdio_release_host(func);
246}
247
248static void send_sdu(struct sdio_func *func, struct tx_cxt *tx)
249{
250	struct list_head *l, *next;
251	struct hci_s *hci;
252	struct sdio_tx *t;
253	int pos, len, i, estlen, aggr_num = 0, aggr_len;
254	u8 *buf;
255	unsigned long flags;
256
257	spin_lock_irqsave(&tx->lock, flags);
258
259	pos = TYPE_A_HEADER_SIZE + HCI_HEADER_SIZE;
260	list_for_each_entry(t, &tx->sdu_list, list) {
261		estlen = ((t->len + 3) & ~3) + 4;
262		if ((pos + estlen) > SDU_TX_BUF_SIZE)
263			break;
264
265		aggr_num++;
266		memcpy(tx->sdu_buf + pos, t->buf, t->len);
267		memset(tx->sdu_buf + pos + t->len, 0, estlen - t->len);
268		pos += estlen;
269	}
270	aggr_len = pos;
271
272	hci = (struct hci_s *)(tx->sdu_buf + TYPE_A_HEADER_SIZE);
273	hci->cmd_evt = cpu_to_be16(WIMAX_TX_SDU_AGGR);
274	hci->length = cpu_to_be16(aggr_len - TYPE_A_HEADER_SIZE -
275				  HCI_HEADER_SIZE);
276
277	spin_unlock_irqrestore(&tx->lock, flags);
278
279	dev_dbg(&func->dev, "sdio_send: %*ph\n", aggr_len - TYPE_A_HEADER_SIZE,
280		tx->sdu_buf + TYPE_A_HEADER_SIZE);
281
282	for (pos = TYPE_A_HEADER_SIZE; pos < aggr_len; pos += TX_CHUNK_SIZE) {
283		len = aggr_len - pos;
284		len = len > TX_CHUNK_SIZE ? TX_CHUNK_SIZE : len;
285		buf = tx->sdu_buf + pos - TYPE_A_HEADER_SIZE;
286
287		buf[0] = len & 0xff;
288		buf[1] = (len >> 8) & 0xff;
289		buf[2] = (len >> 16) & 0xff;
290		buf[3] = (pos + len) >= aggr_len ? 0 : 1;
291		send_sdio_pkt(func, buf, len + TYPE_A_HEADER_SIZE);
292	}
293
294	spin_lock_irqsave(&tx->lock, flags);
295
296	for (l = tx->sdu_list.next, i = 0; i < aggr_num; i++, l = next) {
297		next = l->next;
298		t = list_entry(l, struct sdio_tx, list);
299		if (t->callback)
300			t->callback(t->cb_data);
301
302		list_del(l);
303		put_tx_struct(t->tx_cxt, t);
304	}
305
306	do_gettimeofday(&tx->sdu_stamp);
307	spin_unlock_irqrestore(&tx->lock, flags);
308}
309
310static void send_hci(struct sdio_func *func, struct tx_cxt *tx,
311		     struct sdio_tx *t)
312{
313	unsigned long flags;
314
315	dev_dbg(&func->dev, "sdio_send: %*ph\n", t->len - TYPE_A_HEADER_SIZE,
316		t->buf + TYPE_A_HEADER_SIZE);
317
318	send_sdio_pkt(func, t->buf, t->len);
319
320	spin_lock_irqsave(&tx->lock, flags);
321	if (t->callback)
322		t->callback(t->cb_data);
323	free_tx_struct(t);
324	spin_unlock_irqrestore(&tx->lock, flags);
325}
326
327static void do_tx(struct work_struct *work)
328{
329	struct sdiowm_dev *sdev = container_of(work, struct sdiowm_dev, ws);
330	struct sdio_func *func = sdev->func;
331	struct tx_cxt *tx = &sdev->tx;
332	struct sdio_tx *t = NULL;
333	struct timeval now, *before;
334	int is_sdu = 0;
335	long diff;
336	unsigned long flags;
337
338	spin_lock_irqsave(&tx->lock, flags);
339	if (!tx->can_send) {
340		spin_unlock_irqrestore(&tx->lock, flags);
341		return;
342	}
343
344	if (!list_empty(&tx->hci_list)) {
345		t = list_entry(tx->hci_list.next, struct sdio_tx, list);
346		list_del(&t->list);
347		is_sdu = 0;
348	} else if (!tx->stop_sdu_tx && !list_empty(&tx->sdu_list)) {
349		do_gettimeofday(&now);
350		before = &tx->sdu_stamp;
351
352		diff = (now.tv_sec - before->tv_sec) * 1000000 +
353			(now.tv_usec - before->tv_usec);
354		if (diff >= 0 && diff < TX_INTERVAL) {
355			schedule_work(&sdev->ws);
356			spin_unlock_irqrestore(&tx->lock, flags);
357			return;
358		}
359		is_sdu = 1;
360	}
361
362	if (!is_sdu && t == NULL) {
363		spin_unlock_irqrestore(&tx->lock, flags);
364		return;
365	}
366
367	tx->can_send = 0;
368
369	spin_unlock_irqrestore(&tx->lock, flags);
370
371	if (is_sdu)
372		send_sdu(func, tx);
373	else
374		send_hci(func, tx, t);
375}
376
377static int gdm_sdio_send(void *priv_dev, void *data, int len,
378			 void (*cb)(void *data), void *cb_data)
379{
380	struct sdiowm_dev *sdev = priv_dev;
381	struct tx_cxt *tx = &sdev->tx;
382	struct sdio_tx *t;
383	u8 *pkt = data;
384	int no_spc = 0;
385	u16 cmd_evt;
386	unsigned long flags;
387
388	if (len > TX_BUF_SIZE - TYPE_A_HEADER_SIZE)
389		return -EINVAL;
390
391	spin_lock_irqsave(&tx->lock, flags);
392
393	cmd_evt = (pkt[0] << 8) | pkt[1];
394	if (cmd_evt == WIMAX_TX_SDU) {
395		t = get_tx_struct(tx, &no_spc);
396		if (t == NULL) {
397			/* This case must not happen. */
398			spin_unlock_irqrestore(&tx->lock, flags);
399			return -ENOSPC;
400		}
401		list_add_tail(&t->list, &tx->sdu_list);
402
403		memcpy(t->buf, data, len);
404
405		t->len = len;
406		t->callback = cb;
407		t->cb_data = cb_data;
408	} else {
409		t = alloc_tx_struct(tx);
410		if (t == NULL) {
411			spin_unlock_irqrestore(&tx->lock, flags);
412			return -ENOMEM;
413		}
414		list_add_tail(&t->list, &tx->hci_list);
415
416		t->buf[0] = len & 0xff;
417		t->buf[1] = (len >> 8) & 0xff;
418		t->buf[2] = (len >> 16) & 0xff;
419		t->buf[3] = 2;
420		memcpy(t->buf + TYPE_A_HEADER_SIZE, data, len);
421
422		t->len = len + TYPE_A_HEADER_SIZE;
423		t->callback = cb;
424		t->cb_data = cb_data;
425	}
426
427	if (tx->can_send)
428		schedule_work(&sdev->ws);
429
430	spin_unlock_irqrestore(&tx->lock, flags);
431
432	if (no_spc)
433		return -ENOSPC;
434
435	return 0;
436}
437
438/* Handle the HCI, WIMAX_SDU_TX_FLOW. */
439static int control_sdu_tx_flow(struct sdiowm_dev *sdev, u8 *hci_data, int len)
440{
441	struct tx_cxt *tx = &sdev->tx;
442	u16 cmd_evt;
443	unsigned long flags;
444
445	spin_lock_irqsave(&tx->lock, flags);
446
447	cmd_evt = (hci_data[0] << 8) | (hci_data[1]);
448	if (cmd_evt != WIMAX_SDU_TX_FLOW)
449		goto out;
450
451	if (hci_data[4] == 0) {
452		dev_dbg(&sdev->func->dev, "WIMAX ==> STOP SDU TX\n");
453		tx->stop_sdu_tx = 1;
454	} else if (hci_data[4] == 1) {
455		dev_dbg(&sdev->func->dev, "WIMAX ==> START SDU TX\n");
456		tx->stop_sdu_tx = 0;
457		if (tx->can_send)
458			schedule_work(&sdev->ws);
459		/* If free buffer for sdu tx doesn't exist, then tx queue
460		 * should not be woken. For this reason, don't pass the command,
461		 * START_SDU_TX.
462		 */
463		if (list_empty(&tx->free_list))
464			len = 0;
465	}
466
467out:
468	spin_unlock_irqrestore(&tx->lock, flags);
469	return len;
470}
471
472static void gdm_sdio_irq(struct sdio_func *func)
473{
474	struct phy_dev *phy_dev = sdio_get_drvdata(func);
475	struct sdiowm_dev *sdev = phy_dev->priv_dev;
476	struct tx_cxt *tx = &sdev->tx;
477	struct rx_cxt *rx = &sdev->rx;
478	struct sdio_rx *r;
479	unsigned long flags;
480	u8 val, hdr[TYPE_A_LOOKAHEAD_SIZE], *buf;
481	u32 len, blocks, n;
482	int ret, remain;
483
484	/* Check interrupt */
485	val = sdio_readb(func, 0x13, &ret);
486	if (val & 0x01)
487		sdio_writeb(func, 0x01, 0x13, &ret);	/* clear interrupt */
488	else
489		return;
490
491	ret = sdio_memcpy_fromio(func, hdr, 0x0, TYPE_A_LOOKAHEAD_SIZE);
492	if (ret) {
493		dev_err(&func->dev,
494			"Cannot read from function %d\n", func->num);
495		goto done;
496	}
497
498	len = (hdr[2] << 16) | (hdr[1] << 8) | hdr[0];
499	if (len > (RX_BUF_SIZE - TYPE_A_HEADER_SIZE)) {
500		dev_err(&func->dev, "Too big Type-A size: %d\n", len);
501		goto done;
502	}
503
504	if (hdr[3] == 1) {	/* Ack */
505		u32 *ack_seq = (u32 *)&hdr[4];
506
507		spin_lock_irqsave(&tx->lock, flags);
508		tx->can_send = 1;
509
510		if (!list_empty(&tx->sdu_list) || !list_empty(&tx->hci_list))
511			schedule_work(&sdev->ws);
512		spin_unlock_irqrestore(&tx->lock, flags);
513		dev_dbg(&func->dev, "Ack... %0x\n", ntohl(*ack_seq));
514		goto done;
515	}
516
517	memcpy(rx->rx_buf, hdr + TYPE_A_HEADER_SIZE,
518	       TYPE_A_LOOKAHEAD_SIZE - TYPE_A_HEADER_SIZE);
519
520	buf = rx->rx_buf + TYPE_A_LOOKAHEAD_SIZE - TYPE_A_HEADER_SIZE;
521	remain = len - TYPE_A_LOOKAHEAD_SIZE + TYPE_A_HEADER_SIZE;
522	if (remain <= 0)
523		goto end_io;
524
525	blocks = remain / func->cur_blksize;
526
527	if (blocks) {
528		n = blocks * func->cur_blksize;
529		ret = sdio_memcpy_fromio(func, buf, 0x0, n);
530		if (ret) {
531			dev_err(&func->dev,
532				"Cannot read from function %d\n", func->num);
533			goto done;
534		}
535		buf += n;
536		remain -= n;
537	}
538
539	if (remain) {
540		ret = sdio_memcpy_fromio(func, buf, 0x0, remain);
541		if (ret) {
542			dev_err(&func->dev,
543				"Cannot read from function %d\n", func->num);
544			goto done;
545		}
546	}
547
548end_io:
549	dev_dbg(&func->dev, "sdio_receive: %*ph\n", len, rx->rx_buf);
550
551	len = control_sdu_tx_flow(sdev, rx->rx_buf, len);
552
553	spin_lock_irqsave(&rx->lock, flags);
554
555	if (!list_empty(&rx->req_list)) {
556		r = list_entry(rx->req_list.next, struct sdio_rx, list);
557		spin_unlock_irqrestore(&rx->lock, flags);
558		if (r->callback)
559			r->callback(r->cb_data, rx->rx_buf, len);
560		spin_lock_irqsave(&rx->lock, flags);
561		list_del(&r->list);
562		put_rx_struct(rx, r);
563	}
564
565	spin_unlock_irqrestore(&rx->lock, flags);
566
567done:
568	sdio_writeb(func, 0x00, 0x10, &ret);	/* PCRRT */
569	if (!phy_dev->netdev)
570		register_wimax_device(phy_dev, &func->dev);
571}
572
573static int gdm_sdio_receive(void *priv_dev,
574			    void (*cb)(void *cb_data, void *data, int len),
575			    void *cb_data)
576{
577	struct sdiowm_dev *sdev = priv_dev;
578	struct rx_cxt *rx = &sdev->rx;
579	struct sdio_rx *r;
580	unsigned long flags;
581
582	spin_lock_irqsave(&rx->lock, flags);
583	r = get_rx_struct(rx);
584	if (r == NULL) {
585		spin_unlock_irqrestore(&rx->lock, flags);
586		return -ENOMEM;
587	}
588
589	r->callback = cb;
590	r->cb_data = cb_data;
591
592	list_add_tail(&r->list, &rx->req_list);
593	spin_unlock_irqrestore(&rx->lock, flags);
594
595	return 0;
596}
597
598static int sdio_wimax_probe(struct sdio_func *func,
599			    const struct sdio_device_id *id)
600{
601	int ret;
602	struct phy_dev *phy_dev = NULL;
603	struct sdiowm_dev *sdev = NULL;
604
605	dev_info(&func->dev, "Found GDM SDIO VID = 0x%04x PID = 0x%04x...\n",
606		 func->vendor, func->device);
607	dev_info(&func->dev, "GCT WiMax driver version %s\n", DRIVER_VERSION);
608
609	sdio_claim_host(func);
610	sdio_enable_func(func);
611	sdio_claim_irq(func, gdm_sdio_irq);
612
613	ret = sdio_boot(func);
614	if (ret)
615		return ret;
616
617	phy_dev = kzalloc(sizeof(*phy_dev), GFP_KERNEL);
618	if (phy_dev == NULL) {
619		ret = -ENOMEM;
620		goto out;
621	}
622	sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
623	if (sdev == NULL) {
624		ret = -ENOMEM;
625		goto out;
626	}
627
628	phy_dev->priv_dev = (void *)sdev;
629	phy_dev->send_func = gdm_sdio_send;
630	phy_dev->rcv_func = gdm_sdio_receive;
631
632	ret = init_sdio(sdev);
633	if (ret < 0)
634		goto out;
635
636	sdev->func = func;
637
638	sdio_writeb(func, 1, 0x14, &ret);	/* Enable interrupt */
639	sdio_release_host(func);
640
641	INIT_WORK(&sdev->ws, do_tx);
642
643	sdio_set_drvdata(func, phy_dev);
644out:
645	if (ret) {
646		kfree(phy_dev);
647		kfree(sdev);
648	}
649
650	return ret;
651}
652
653static void sdio_wimax_remove(struct sdio_func *func)
654{
655	struct phy_dev *phy_dev = sdio_get_drvdata(func);
656	struct sdiowm_dev *sdev = phy_dev->priv_dev;
657
658	cancel_work_sync(&sdev->ws);
659	if (phy_dev->netdev)
660		unregister_wimax_device(phy_dev);
661	sdio_claim_host(func);
662	sdio_release_irq(func);
663	sdio_disable_func(func);
664	sdio_release_host(func);
665	release_sdio(sdev);
666
667	kfree(sdev);
668	kfree(phy_dev);
669}
670
671static const struct sdio_device_id sdio_wimax_ids[] = {
672	{ SDIO_DEVICE(0x0296, 0x5347) },
673	{0}
674};
675
676MODULE_DEVICE_TABLE(sdio, sdio_wimax_ids);
677
678static struct sdio_driver sdio_wimax_driver = {
679	.probe		= sdio_wimax_probe,
680	.remove		= sdio_wimax_remove,
681	.name		= "sdio_wimax",
682	.id_table	= sdio_wimax_ids,
683};
684
685static int __init sdio_gdm_wimax_init(void)
686{
687	return sdio_register_driver(&sdio_wimax_driver);
688}
689
690static void __exit sdio_gdm_wimax_exit(void)
691{
692	sdio_unregister_driver(&sdio_wimax_driver);
693}
694
695module_init(sdio_gdm_wimax_init);
696module_exit(sdio_gdm_wimax_exit);
697
698MODULE_VERSION(DRIVER_VERSION);
699MODULE_DESCRIPTION("GCT WiMax SDIO Device Driver");
700MODULE_AUTHOR("Ethan Park");
701MODULE_LICENSE("GPL");
702