1/*
2 *  Texas Instrument's NFC Driver For Shared Transport.
3 *
4 *  NFC Driver acts as interface between NCI core and
5 *  TI Shared Transport Layer.
6 *
7 *  Copyright (C) 2011 Texas Instruments, Inc.
8 *
9 *  Written by Ilan Elias <ilane@ti.com>
10 *
11 *  Acknowledgements:
12 *  This file is based on btwilink.c, which was written
13 *  by Raja Mani and Pavan Savoy.
14 *
15 *  This program is free software; you can redistribute it and/or modify
16 *  it under the terms of the GNU General Public License version 2 as
17 *  published by the Free Software Foundation.
18 *
19 *  This program is distributed in the hope that it will be useful,
20 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
21 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22 *  GNU General Public License for more details.
23 *
24 *  You should have received a copy of the GNU General Public License
25 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
26 *
27 */
28#include <linux/platform_device.h>
29#include <linux/module.h>
30#include <linux/types.h>
31#include <linux/firmware.h>
32#include <linux/nfc.h>
33#include <net/nfc/nci.h>
34#include <net/nfc/nci_core.h>
35#include <linux/ti_wilink_st.h>
36
37#define NFCWILINK_CHNL			12
38#define NFCWILINK_OPCODE		7
39#define NFCWILINK_MAX_FRAME_SIZE	300
40#define NFCWILINK_HDR_LEN		4
41#define NFCWILINK_OFFSET_LEN_IN_HDR	1
42#define NFCWILINK_LEN_SIZE		2
43#define NFCWILINK_REGISTER_TIMEOUT	8000	/* 8 sec */
44#define NFCWILINK_CMD_TIMEOUT		5000	/* 5 sec */
45
46#define BTS_FILE_NAME_MAX_SIZE		40
47#define BTS_FILE_HDR_MAGIC		0x42535442
48#define BTS_FILE_CMD_MAX_LEN		0xff
49#define BTS_FILE_ACTION_TYPE_SEND_CMD	1
50
51#define NCI_VS_NFCC_INFO_CMD_GID	0x2f
52#define NCI_VS_NFCC_INFO_CMD_OID	0x12
53#define NCI_VS_NFCC_INFO_RSP_GID	0x4f
54#define NCI_VS_NFCC_INFO_RSP_OID	0x12
55
56struct nfcwilink_hdr {
57	__u8 chnl;
58	__u8 opcode;
59	__le16 len;
60} __packed;
61
62struct nci_vs_nfcc_info_cmd {
63	__u8 gid;
64	__u8 oid;
65	__u8 plen;
66} __packed;
67
68struct nci_vs_nfcc_info_rsp {
69	__u8 gid;
70	__u8 oid;
71	__u8 plen;
72	__u8 status;
73	__u8 hw_id;
74	__u8 sw_ver_x;
75	__u8 sw_ver_z;
76	__u8 patch_id;
77} __packed;
78
79struct bts_file_hdr {
80	__le32 magic;
81	__le32 ver;
82	__u8 rfu[24];
83	__u8 actions[0];
84} __packed;
85
86struct bts_file_action {
87	__le16 type;
88	__le16 len;
89	__u8 data[0];
90} __packed;
91
92struct nfcwilink {
93	struct platform_device		*pdev;
94	struct nci_dev			*ndev;
95	unsigned long			flags;
96
97	char				st_register_cb_status;
98	long				(*st_write) (struct sk_buff *);
99
100	struct completion		completed;
101
102	struct nci_vs_nfcc_info_rsp	nfcc_info;
103};
104
105/* NFCWILINK driver flags */
106enum {
107	NFCWILINK_RUNNING,
108	NFCWILINK_FW_DOWNLOAD,
109};
110
111static int nfcwilink_send(struct nci_dev *ndev, struct sk_buff *skb);
112
113static inline struct sk_buff *nfcwilink_skb_alloc(unsigned int len, gfp_t how)
114{
115	struct sk_buff *skb;
116
117	skb = alloc_skb(len + NFCWILINK_HDR_LEN, how);
118	if (skb)
119		skb_reserve(skb, NFCWILINK_HDR_LEN);
120
121	return skb;
122}
123
124static void nfcwilink_fw_download_receive(struct nfcwilink *drv,
125						struct sk_buff *skb)
126{
127	struct nci_vs_nfcc_info_rsp *rsp = (void *)skb->data;
128
129	/* Detect NCI_VS_NFCC_INFO_RSP and store the result */
130	if ((skb->len > 3) && (rsp->gid == NCI_VS_NFCC_INFO_RSP_GID) &&
131		(rsp->oid == NCI_VS_NFCC_INFO_RSP_OID)) {
132		memcpy(&drv->nfcc_info, rsp,
133			sizeof(struct nci_vs_nfcc_info_rsp));
134	}
135
136	kfree_skb(skb);
137
138	complete(&drv->completed);
139}
140
141static int nfcwilink_get_bts_file_name(struct nfcwilink *drv, char *file_name)
142{
143	struct nci_vs_nfcc_info_cmd *cmd;
144	struct sk_buff *skb;
145	unsigned long comp_ret;
146	int rc;
147
148	skb = nfcwilink_skb_alloc(sizeof(struct nci_vs_nfcc_info_cmd),
149					GFP_KERNEL);
150	if (!skb) {
151		nfc_err(&drv->pdev->dev,
152			"no memory for nci_vs_nfcc_info_cmd\n");
153		return -ENOMEM;
154	}
155
156	cmd = (struct nci_vs_nfcc_info_cmd *)
157			skb_put(skb, sizeof(struct nci_vs_nfcc_info_cmd));
158	cmd->gid = NCI_VS_NFCC_INFO_CMD_GID;
159	cmd->oid = NCI_VS_NFCC_INFO_CMD_OID;
160	cmd->plen = 0;
161
162	drv->nfcc_info.plen = 0;
163
164	rc = nfcwilink_send(drv->ndev, skb);
165	if (rc)
166		return rc;
167
168	comp_ret = wait_for_completion_timeout(&drv->completed,
169				msecs_to_jiffies(NFCWILINK_CMD_TIMEOUT));
170	dev_dbg(&drv->pdev->dev, "wait_for_completion_timeout returned %ld\n",
171		comp_ret);
172	if (comp_ret == 0) {
173		nfc_err(&drv->pdev->dev,
174			"timeout on wait_for_completion_timeout\n");
175		return -ETIMEDOUT;
176	}
177
178	dev_dbg(&drv->pdev->dev, "nci_vs_nfcc_info_rsp: plen %d, status %d\n",
179		drv->nfcc_info.plen, drv->nfcc_info.status);
180
181	if ((drv->nfcc_info.plen != 5) || (drv->nfcc_info.status != 0)) {
182		nfc_err(&drv->pdev->dev, "invalid nci_vs_nfcc_info_rsp\n");
183		return -EINVAL;
184	}
185
186	snprintf(file_name, BTS_FILE_NAME_MAX_SIZE,
187			"TINfcInit_%d.%d.%d.%d.bts",
188			drv->nfcc_info.hw_id,
189			drv->nfcc_info.sw_ver_x,
190			drv->nfcc_info.sw_ver_z,
191			drv->nfcc_info.patch_id);
192
193	nfc_info(&drv->pdev->dev, "nfcwilink FW file name: %s\n", file_name);
194
195	return 0;
196}
197
198static int nfcwilink_send_bts_cmd(struct nfcwilink *drv, __u8 *data, int len)
199{
200	struct nfcwilink_hdr *hdr = (struct nfcwilink_hdr *)data;
201	struct sk_buff *skb;
202	unsigned long comp_ret;
203	int rc;
204
205	/* verify valid cmd for the NFC channel */
206	if ((len <= sizeof(struct nfcwilink_hdr)) ||
207		(len > BTS_FILE_CMD_MAX_LEN) ||
208		(hdr->chnl != NFCWILINK_CHNL) ||
209		(hdr->opcode != NFCWILINK_OPCODE)) {
210		nfc_err(&drv->pdev->dev,
211			"ignoring invalid bts cmd, len %d, chnl %d, opcode %d\n",
212			len, hdr->chnl, hdr->opcode);
213		return 0;
214	}
215
216	/* remove the ST header */
217	len -= sizeof(struct nfcwilink_hdr);
218	data += sizeof(struct nfcwilink_hdr);
219
220	skb = nfcwilink_skb_alloc(len, GFP_KERNEL);
221	if (!skb) {
222		nfc_err(&drv->pdev->dev, "no memory for bts cmd\n");
223		return -ENOMEM;
224	}
225
226	memcpy(skb_put(skb, len), data, len);
227
228	rc = nfcwilink_send(drv->ndev, skb);
229	if (rc)
230		return rc;
231
232	comp_ret = wait_for_completion_timeout(&drv->completed,
233				msecs_to_jiffies(NFCWILINK_CMD_TIMEOUT));
234	dev_dbg(&drv->pdev->dev, "wait_for_completion_timeout returned %ld\n",
235		comp_ret);
236	if (comp_ret == 0) {
237		nfc_err(&drv->pdev->dev,
238			"timeout on wait_for_completion_timeout\n");
239		return -ETIMEDOUT;
240	}
241
242	return 0;
243}
244
245static int nfcwilink_download_fw(struct nfcwilink *drv)
246{
247	unsigned char file_name[BTS_FILE_NAME_MAX_SIZE];
248	const struct firmware *fw;
249	__u16 action_type, action_len;
250	__u8 *ptr;
251	int len, rc;
252
253	set_bit(NFCWILINK_FW_DOWNLOAD, &drv->flags);
254
255	rc = nfcwilink_get_bts_file_name(drv, file_name);
256	if (rc)
257		goto exit;
258
259	rc = request_firmware(&fw, file_name, &drv->pdev->dev);
260	if (rc) {
261		nfc_err(&drv->pdev->dev, "request_firmware failed %d\n", rc);
262
263		/* if the file is not found, don't exit with failure */
264		if (rc == -ENOENT)
265			rc = 0;
266
267		goto exit;
268	}
269
270	len = fw->size;
271	ptr = (__u8 *)fw->data;
272
273	if ((len == 0) || (ptr == NULL)) {
274		dev_dbg(&drv->pdev->dev,
275			"request_firmware returned size %d\n", len);
276		goto release_fw;
277	}
278
279	if (__le32_to_cpu(((struct bts_file_hdr *)ptr)->magic) !=
280			BTS_FILE_HDR_MAGIC) {
281		nfc_err(&drv->pdev->dev, "wrong bts magic number\n");
282		rc = -EINVAL;
283		goto release_fw;
284	}
285
286	/* remove the BTS header */
287	len -= sizeof(struct bts_file_hdr);
288	ptr += sizeof(struct bts_file_hdr);
289
290	while (len > 0) {
291		action_type =
292			__le16_to_cpu(((struct bts_file_action *)ptr)->type);
293		action_len =
294			__le16_to_cpu(((struct bts_file_action *)ptr)->len);
295
296		dev_dbg(&drv->pdev->dev, "bts_file_action type %d, len %d\n",
297			action_type, action_len);
298
299		switch (action_type) {
300		case BTS_FILE_ACTION_TYPE_SEND_CMD:
301			rc = nfcwilink_send_bts_cmd(drv,
302					((struct bts_file_action *)ptr)->data,
303					action_len);
304			if (rc)
305				goto release_fw;
306			break;
307		}
308
309		/* advance to the next action */
310		len -= (sizeof(struct bts_file_action) + action_len);
311		ptr += (sizeof(struct bts_file_action) + action_len);
312	}
313
314release_fw:
315	release_firmware(fw);
316
317exit:
318	clear_bit(NFCWILINK_FW_DOWNLOAD, &drv->flags);
319	return rc;
320}
321
322/* Called by ST when registration is complete */
323static void nfcwilink_register_complete(void *priv_data, char data)
324{
325	struct nfcwilink *drv = priv_data;
326
327	/* store ST registration status */
328	drv->st_register_cb_status = data;
329
330	/* complete the wait in nfc_st_open() */
331	complete(&drv->completed);
332}
333
334/* Called by ST when receive data is available */
335static long nfcwilink_receive(void *priv_data, struct sk_buff *skb)
336{
337	struct nfcwilink *drv = priv_data;
338	int rc;
339
340	if (!skb)
341		return -EFAULT;
342
343	if (!drv) {
344		kfree_skb(skb);
345		return -EFAULT;
346	}
347
348	dev_dbg(&drv->pdev->dev, "receive entry, len %d\n", skb->len);
349
350	/* strip the ST header
351	(apart for the chnl byte, which is not received in the hdr) */
352	skb_pull(skb, (NFCWILINK_HDR_LEN-1));
353
354	if (test_bit(NFCWILINK_FW_DOWNLOAD, &drv->flags)) {
355		nfcwilink_fw_download_receive(drv, skb);
356		return 0;
357	}
358
359	/* Forward skb to NCI core layer */
360	rc = nci_recv_frame(drv->ndev, skb);
361	if (rc < 0) {
362		nfc_err(&drv->pdev->dev, "nci_recv_frame failed %d\n", rc);
363		return rc;
364	}
365
366	return 0;
367}
368
369/* protocol structure registered with ST */
370static struct st_proto_s nfcwilink_proto = {
371	.chnl_id = NFCWILINK_CHNL,
372	.max_frame_size = NFCWILINK_MAX_FRAME_SIZE,
373	.hdr_len = (NFCWILINK_HDR_LEN-1),	/* not including chnl byte */
374	.offset_len_in_hdr = NFCWILINK_OFFSET_LEN_IN_HDR,
375	.len_size = NFCWILINK_LEN_SIZE,
376	.reserve = 0,
377	.recv = nfcwilink_receive,
378	.reg_complete_cb = nfcwilink_register_complete,
379	.write = NULL,
380};
381
382static int nfcwilink_open(struct nci_dev *ndev)
383{
384	struct nfcwilink *drv = nci_get_drvdata(ndev);
385	unsigned long comp_ret;
386	int rc;
387
388	if (test_and_set_bit(NFCWILINK_RUNNING, &drv->flags)) {
389		rc = -EBUSY;
390		goto exit;
391	}
392
393	nfcwilink_proto.priv_data = drv;
394
395	init_completion(&drv->completed);
396	drv->st_register_cb_status = -EINPROGRESS;
397
398	rc = st_register(&nfcwilink_proto);
399	if (rc < 0) {
400		if (rc == -EINPROGRESS) {
401			comp_ret = wait_for_completion_timeout(
402			&drv->completed,
403			msecs_to_jiffies(NFCWILINK_REGISTER_TIMEOUT));
404
405			dev_dbg(&drv->pdev->dev,
406				"wait_for_completion_timeout returned %ld\n",
407				comp_ret);
408
409			if (comp_ret == 0) {
410				/* timeout */
411				rc = -ETIMEDOUT;
412				goto clear_exit;
413			} else if (drv->st_register_cb_status != 0) {
414				rc = drv->st_register_cb_status;
415				nfc_err(&drv->pdev->dev,
416					"st_register_cb failed %d\n", rc);
417				goto clear_exit;
418			}
419		} else {
420			nfc_err(&drv->pdev->dev, "st_register failed %d\n", rc);
421			goto clear_exit;
422		}
423	}
424
425	/* st_register MUST fill the write callback */
426	BUG_ON(nfcwilink_proto.write == NULL);
427	drv->st_write = nfcwilink_proto.write;
428
429	if (nfcwilink_download_fw(drv)) {
430		nfc_err(&drv->pdev->dev, "nfcwilink_download_fw failed %d\n",
431			rc);
432		/* open should succeed, even if the FW download failed */
433	}
434
435	goto exit;
436
437clear_exit:
438	clear_bit(NFCWILINK_RUNNING, &drv->flags);
439
440exit:
441	return rc;
442}
443
444static int nfcwilink_close(struct nci_dev *ndev)
445{
446	struct nfcwilink *drv = nci_get_drvdata(ndev);
447	int rc;
448
449	if (!test_and_clear_bit(NFCWILINK_RUNNING, &drv->flags))
450		return 0;
451
452	rc = st_unregister(&nfcwilink_proto);
453	if (rc)
454		nfc_err(&drv->pdev->dev, "st_unregister failed %d\n", rc);
455
456	drv->st_write = NULL;
457
458	return rc;
459}
460
461static int nfcwilink_send(struct nci_dev *ndev, struct sk_buff *skb)
462{
463	struct nfcwilink *drv = nci_get_drvdata(ndev);
464	struct nfcwilink_hdr hdr = {NFCWILINK_CHNL, NFCWILINK_OPCODE, 0x0000};
465	long len;
466
467	dev_dbg(&drv->pdev->dev, "send entry, len %d\n", skb->len);
468
469	if (!test_bit(NFCWILINK_RUNNING, &drv->flags)) {
470		kfree_skb(skb);
471		return -EINVAL;
472	}
473
474	/* add the ST hdr to the start of the buffer */
475	hdr.len = cpu_to_le16(skb->len);
476	memcpy(skb_push(skb, NFCWILINK_HDR_LEN), &hdr, NFCWILINK_HDR_LEN);
477
478	/* Insert skb to shared transport layer's transmit queue.
479	 * Freeing skb memory is taken care in shared transport layer,
480	 * so don't free skb memory here.
481	 */
482	len = drv->st_write(skb);
483	if (len < 0) {
484		kfree_skb(skb);
485		nfc_err(&drv->pdev->dev, "st_write failed %ld\n", len);
486		return -EFAULT;
487	}
488
489	return 0;
490}
491
492static struct nci_ops nfcwilink_ops = {
493	.open = nfcwilink_open,
494	.close = nfcwilink_close,
495	.send = nfcwilink_send,
496};
497
498static int nfcwilink_probe(struct platform_device *pdev)
499{
500	struct nfcwilink *drv;
501	int rc;
502	__u32 protocols;
503
504	drv = devm_kzalloc(&pdev->dev, sizeof(struct nfcwilink), GFP_KERNEL);
505	if (!drv) {
506		rc = -ENOMEM;
507		goto exit;
508	}
509
510	drv->pdev = pdev;
511
512	protocols = NFC_PROTO_JEWEL_MASK
513		| NFC_PROTO_MIFARE_MASK | NFC_PROTO_FELICA_MASK
514		| NFC_PROTO_ISO14443_MASK
515		| NFC_PROTO_ISO14443_B_MASK
516		| NFC_PROTO_NFC_DEP_MASK;
517
518	drv->ndev = nci_allocate_device(&nfcwilink_ops,
519					protocols,
520					NFCWILINK_HDR_LEN,
521					0);
522	if (!drv->ndev) {
523		nfc_err(&pdev->dev, "nci_allocate_device failed\n");
524		rc = -ENOMEM;
525		goto exit;
526	}
527
528	nci_set_parent_dev(drv->ndev, &pdev->dev);
529	nci_set_drvdata(drv->ndev, drv);
530
531	rc = nci_register_device(drv->ndev);
532	if (rc < 0) {
533		nfc_err(&pdev->dev, "nci_register_device failed %d\n", rc);
534		goto free_dev_exit;
535	}
536
537	dev_set_drvdata(&pdev->dev, drv);
538
539	goto exit;
540
541free_dev_exit:
542	nci_free_device(drv->ndev);
543
544exit:
545	return rc;
546}
547
548static int nfcwilink_remove(struct platform_device *pdev)
549{
550	struct nfcwilink *drv = dev_get_drvdata(&pdev->dev);
551	struct nci_dev *ndev;
552
553	if (!drv)
554		return -EFAULT;
555
556	ndev = drv->ndev;
557
558	nci_unregister_device(ndev);
559	nci_free_device(ndev);
560
561	return 0;
562}
563
564static struct platform_driver nfcwilink_driver = {
565	.probe = nfcwilink_probe,
566	.remove = nfcwilink_remove,
567	.driver = {
568		.name = "nfcwilink",
569	},
570};
571
572module_platform_driver(nfcwilink_driver);
573
574/* ------ Module Info ------ */
575
576MODULE_AUTHOR("Ilan Elias <ilane@ti.com>");
577MODULE_DESCRIPTION("NFC Driver for TI Shared Transport");
578MODULE_LICENSE("GPL");
579