1/*
2 *
3 * Intel Management Engine Interface (Intel MEI) Linux driver
4 * Copyright (c) 2003-2013, Intel Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13 * more details.
14 *
15 */
16
17#include <linux/kernel.h>
18#include <linux/sched.h>
19#include <linux/module.h>
20#include <linux/moduleparam.h>
21#include <linux/device.h>
22#include <linux/slab.h>
23
24#include <linux/mei_cl_bus.h>
25
26#include "mei_dev.h"
27#include "client.h"
28
29struct mei_nfc_cmd {
30	u8 command;
31	u8 status;
32	u16 req_id;
33	u32 reserved;
34	u16 data_size;
35	u8 sub_command;
36	u8 data[];
37} __packed;
38
39struct mei_nfc_reply {
40	u8 command;
41	u8 status;
42	u16 req_id;
43	u32 reserved;
44	u16 data_size;
45	u8 sub_command;
46	u8 reply_status;
47	u8 data[];
48} __packed;
49
50struct mei_nfc_if_version {
51	u8 radio_version_sw[3];
52	u8 reserved[3];
53	u8 radio_version_hw[3];
54	u8 i2c_addr;
55	u8 fw_ivn;
56	u8 vendor_id;
57	u8 radio_type;
58} __packed;
59
60struct mei_nfc_connect {
61	u8 fw_ivn;
62	u8 vendor_id;
63} __packed;
64
65struct mei_nfc_connect_resp {
66	u8 fw_ivn;
67	u8 vendor_id;
68	u16 me_major;
69	u16 me_minor;
70	u16 me_hotfix;
71	u16 me_build;
72} __packed;
73
74struct mei_nfc_hci_hdr {
75	u8 cmd;
76	u8 status;
77	u16 req_id;
78	u32 reserved;
79	u16 data_size;
80} __packed;
81
82#define MEI_NFC_CMD_MAINTENANCE 0x00
83#define MEI_NFC_CMD_HCI_SEND 0x01
84#define MEI_NFC_CMD_HCI_RECV 0x02
85
86#define MEI_NFC_SUBCMD_CONNECT    0x00
87#define MEI_NFC_SUBCMD_IF_VERSION 0x01
88
89#define MEI_NFC_HEADER_SIZE 10
90
91/**
92 * struct mei_nfc_dev - NFC mei device
93 *
94 * @cl: NFC host client
95 * @cl_info: NFC info host client
96 * @init_work: perform connection to the info client
97 * @send_wq: send completion wait queue
98 * @fw_ivn: NFC Interface Version Number
99 * @vendor_id: NFC manufacturer ID
100 * @radio_type: NFC radio type
101 * @bus_name: bus name
102 *
103 * @req_id:  message counter
104 * @recv_req_id: reception message counter
105 */
106struct mei_nfc_dev {
107	struct mei_cl *cl;
108	struct mei_cl *cl_info;
109	struct work_struct init_work;
110	wait_queue_head_t send_wq;
111	u8 fw_ivn;
112	u8 vendor_id;
113	u8 radio_type;
114	char *bus_name;
115
116	u16 req_id;
117	u16 recv_req_id;
118};
119
120/* UUIDs for NFC F/W clients */
121const uuid_le mei_nfc_guid = UUID_LE(0x0bb17a78, 0x2a8e, 0x4c50,
122				     0x94, 0xd4, 0x50, 0x26,
123				     0x67, 0x23, 0x77, 0x5c);
124
125static const uuid_le mei_nfc_info_guid = UUID_LE(0xd2de1625, 0x382d, 0x417d,
126					0x48, 0xa4, 0xef, 0xab,
127					0xba, 0x8a, 0x12, 0x06);
128
129/* Vendors */
130#define MEI_NFC_VENDOR_INSIDE 0x00
131#define MEI_NFC_VENDOR_NXP    0x01
132
133/* Radio types */
134#define MEI_NFC_VENDOR_INSIDE_UREAD 0x00
135#define MEI_NFC_VENDOR_NXP_PN544    0x01
136
137static void mei_nfc_free(struct mei_nfc_dev *ndev)
138{
139	if (!ndev)
140		return;
141
142	if (ndev->cl) {
143		list_del(&ndev->cl->device_link);
144		mei_cl_unlink(ndev->cl);
145		kfree(ndev->cl);
146	}
147
148	if (ndev->cl_info) {
149		list_del(&ndev->cl_info->device_link);
150		mei_cl_unlink(ndev->cl_info);
151		kfree(ndev->cl_info);
152	}
153
154	kfree(ndev);
155}
156
157static int mei_nfc_build_bus_name(struct mei_nfc_dev *ndev)
158{
159	struct mei_device *dev;
160
161	if (!ndev->cl)
162		return -ENODEV;
163
164	dev = ndev->cl->dev;
165
166	switch (ndev->vendor_id) {
167	case MEI_NFC_VENDOR_INSIDE:
168		switch (ndev->radio_type) {
169		case MEI_NFC_VENDOR_INSIDE_UREAD:
170			ndev->bus_name = "microread";
171			return 0;
172
173		default:
174			dev_err(dev->dev, "Unknown radio type 0x%x\n",
175				ndev->radio_type);
176
177			return -EINVAL;
178		}
179
180	case MEI_NFC_VENDOR_NXP:
181		switch (ndev->radio_type) {
182		case MEI_NFC_VENDOR_NXP_PN544:
183			ndev->bus_name = "pn544";
184			return 0;
185		default:
186			dev_err(dev->dev, "Unknown radio type 0x%x\n",
187				ndev->radio_type);
188
189			return -EINVAL;
190		}
191
192	default:
193		dev_err(dev->dev, "Unknown vendor ID 0x%x\n",
194			ndev->vendor_id);
195
196		return -EINVAL;
197	}
198
199	return 0;
200}
201
202static int mei_nfc_connect(struct mei_nfc_dev *ndev)
203{
204	struct mei_device *dev;
205	struct mei_cl *cl;
206	struct mei_nfc_cmd *cmd, *reply;
207	struct mei_nfc_connect *connect;
208	struct mei_nfc_connect_resp *connect_resp;
209	size_t connect_length, connect_resp_length;
210	int bytes_recv, ret;
211
212	cl = ndev->cl;
213	dev = cl->dev;
214
215	connect_length = sizeof(struct mei_nfc_cmd) +
216			sizeof(struct mei_nfc_connect);
217
218	connect_resp_length = sizeof(struct mei_nfc_cmd) +
219			sizeof(struct mei_nfc_connect_resp);
220
221	cmd = kzalloc(connect_length, GFP_KERNEL);
222	if (!cmd)
223		return -ENOMEM;
224	connect = (struct mei_nfc_connect *)cmd->data;
225
226	reply = kzalloc(connect_resp_length, GFP_KERNEL);
227	if (!reply) {
228		kfree(cmd);
229		return -ENOMEM;
230	}
231
232	connect_resp = (struct mei_nfc_connect_resp *)reply->data;
233
234	cmd->command = MEI_NFC_CMD_MAINTENANCE;
235	cmd->data_size = 3;
236	cmd->sub_command = MEI_NFC_SUBCMD_CONNECT;
237	connect->fw_ivn = ndev->fw_ivn;
238	connect->vendor_id = ndev->vendor_id;
239
240	ret = __mei_cl_send(cl, (u8 *)cmd, connect_length);
241	if (ret < 0) {
242		dev_err(dev->dev, "Could not send connect cmd\n");
243		goto err;
244	}
245
246	bytes_recv = __mei_cl_recv(cl, (u8 *)reply, connect_resp_length);
247	if (bytes_recv < 0) {
248		dev_err(dev->dev, "Could not read connect response\n");
249		ret = bytes_recv;
250		goto err;
251	}
252
253	dev_info(dev->dev, "IVN 0x%x Vendor ID 0x%x\n",
254		 connect_resp->fw_ivn, connect_resp->vendor_id);
255
256	dev_info(dev->dev, "ME FW %d.%d.%d.%d\n",
257		connect_resp->me_major, connect_resp->me_minor,
258		connect_resp->me_hotfix, connect_resp->me_build);
259
260	ret = 0;
261
262err:
263	kfree(reply);
264	kfree(cmd);
265
266	return ret;
267}
268
269static int mei_nfc_if_version(struct mei_nfc_dev *ndev)
270{
271	struct mei_device *dev;
272	struct mei_cl *cl;
273
274	struct mei_nfc_cmd cmd;
275	struct mei_nfc_reply *reply = NULL;
276	struct mei_nfc_if_version *version;
277	size_t if_version_length;
278	int bytes_recv, ret;
279
280	cl = ndev->cl_info;
281	dev = cl->dev;
282
283	memset(&cmd, 0, sizeof(struct mei_nfc_cmd));
284	cmd.command = MEI_NFC_CMD_MAINTENANCE;
285	cmd.data_size = 1;
286	cmd.sub_command = MEI_NFC_SUBCMD_IF_VERSION;
287
288	ret = __mei_cl_send(cl, (u8 *)&cmd, sizeof(struct mei_nfc_cmd));
289	if (ret < 0) {
290		dev_err(dev->dev, "Could not send IF version cmd\n");
291		return ret;
292	}
293
294	/* to be sure on the stack we alloc memory */
295	if_version_length = sizeof(struct mei_nfc_reply) +
296		sizeof(struct mei_nfc_if_version);
297
298	reply = kzalloc(if_version_length, GFP_KERNEL);
299	if (!reply)
300		return -ENOMEM;
301
302	bytes_recv = __mei_cl_recv(cl, (u8 *)reply, if_version_length);
303	if (bytes_recv < 0 || bytes_recv < sizeof(struct mei_nfc_reply)) {
304		dev_err(dev->dev, "Could not read IF version\n");
305		ret = -EIO;
306		goto err;
307	}
308
309	version = (struct mei_nfc_if_version *)reply->data;
310
311	ndev->fw_ivn = version->fw_ivn;
312	ndev->vendor_id = version->vendor_id;
313	ndev->radio_type = version->radio_type;
314
315err:
316	kfree(reply);
317	return ret;
318}
319
320static int mei_nfc_enable(struct mei_cl_device *cldev)
321{
322	struct mei_device *dev;
323	struct mei_nfc_dev *ndev;
324	int ret;
325
326	ndev = (struct mei_nfc_dev *)cldev->priv_data;
327	dev = ndev->cl->dev;
328
329	ret = mei_nfc_connect(ndev);
330	if (ret < 0) {
331		dev_err(dev->dev, "Could not connect to NFC");
332		return ret;
333	}
334
335	return 0;
336}
337
338static int mei_nfc_disable(struct mei_cl_device *cldev)
339{
340	return 0;
341}
342
343static int mei_nfc_send(struct mei_cl_device *cldev, u8 *buf, size_t length)
344{
345	struct mei_device *dev;
346	struct mei_nfc_dev *ndev;
347	struct mei_nfc_hci_hdr *hdr;
348	u8 *mei_buf;
349	int err;
350
351	ndev = (struct mei_nfc_dev *) cldev->priv_data;
352	dev = ndev->cl->dev;
353
354	err = -ENOMEM;
355	mei_buf = kzalloc(length + MEI_NFC_HEADER_SIZE, GFP_KERNEL);
356	if (!mei_buf)
357		goto out;
358
359	hdr = (struct mei_nfc_hci_hdr *) mei_buf;
360	hdr->cmd = MEI_NFC_CMD_HCI_SEND;
361	hdr->status = 0;
362	hdr->req_id = ndev->req_id;
363	hdr->reserved = 0;
364	hdr->data_size = length;
365
366	memcpy(mei_buf + MEI_NFC_HEADER_SIZE, buf, length);
367	err = __mei_cl_send(ndev->cl, mei_buf, length + MEI_NFC_HEADER_SIZE);
368	if (err < 0)
369		goto out;
370
371	if (!wait_event_interruptible_timeout(ndev->send_wq,
372				ndev->recv_req_id == ndev->req_id, HZ)) {
373		dev_err(dev->dev, "NFC MEI command timeout\n");
374		err = -ETIME;
375	} else {
376		ndev->req_id++;
377	}
378out:
379	kfree(mei_buf);
380	return err;
381}
382
383static int mei_nfc_recv(struct mei_cl_device *cldev, u8 *buf, size_t length)
384{
385	struct mei_nfc_dev *ndev;
386	struct mei_nfc_hci_hdr *hci_hdr;
387	int received_length;
388
389	ndev = (struct mei_nfc_dev *)cldev->priv_data;
390
391	received_length = __mei_cl_recv(ndev->cl, buf, length);
392	if (received_length < 0)
393		return received_length;
394
395	hci_hdr = (struct mei_nfc_hci_hdr *) buf;
396
397	if (hci_hdr->cmd == MEI_NFC_CMD_HCI_SEND) {
398		ndev->recv_req_id = hci_hdr->req_id;
399		wake_up(&ndev->send_wq);
400
401		return 0;
402	}
403
404	return received_length;
405}
406
407static struct mei_cl_ops nfc_ops = {
408	.enable = mei_nfc_enable,
409	.disable = mei_nfc_disable,
410	.send = mei_nfc_send,
411	.recv = mei_nfc_recv,
412};
413
414static void mei_nfc_init(struct work_struct *work)
415{
416	struct mei_device *dev;
417	struct mei_cl_device *cldev;
418	struct mei_nfc_dev *ndev;
419	struct mei_cl *cl_info;
420
421	ndev = container_of(work, struct mei_nfc_dev, init_work);
422
423	cl_info = ndev->cl_info;
424	dev = cl_info->dev;
425
426	mutex_lock(&dev->device_lock);
427
428	if (mei_cl_connect(cl_info, NULL) < 0) {
429		mutex_unlock(&dev->device_lock);
430		dev_err(dev->dev, "Could not connect to the NFC INFO ME client");
431
432		goto err;
433	}
434
435	mutex_unlock(&dev->device_lock);
436
437	if (mei_nfc_if_version(ndev) < 0) {
438		dev_err(dev->dev, "Could not get the NFC interface version");
439
440		goto err;
441	}
442
443	dev_info(dev->dev, "NFC MEI VERSION: IVN 0x%x Vendor ID 0x%x Type 0x%x\n",
444		ndev->fw_ivn, ndev->vendor_id, ndev->radio_type);
445
446	mutex_lock(&dev->device_lock);
447
448	if (mei_cl_disconnect(cl_info) < 0) {
449		mutex_unlock(&dev->device_lock);
450		dev_err(dev->dev, "Could not disconnect the NFC INFO ME client");
451
452		goto err;
453	}
454
455	mutex_unlock(&dev->device_lock);
456
457	if (mei_nfc_build_bus_name(ndev) < 0) {
458		dev_err(dev->dev, "Could not build the bus ID name\n");
459		return;
460	}
461
462	cldev = mei_cl_add_device(dev, mei_nfc_guid, ndev->bus_name, &nfc_ops);
463	if (!cldev) {
464		dev_err(dev->dev, "Could not add the NFC device to the MEI bus\n");
465
466		goto err;
467	}
468
469	cldev->priv_data = ndev;
470
471
472	return;
473
474err:
475	mutex_lock(&dev->device_lock);
476	mei_nfc_free(ndev);
477	mutex_unlock(&dev->device_lock);
478
479}
480
481
482int mei_nfc_host_init(struct mei_device *dev)
483{
484	struct mei_nfc_dev *ndev;
485	struct mei_cl *cl_info, *cl;
486	struct mei_me_client *me_cl = NULL;
487	int ret;
488
489
490	/* in case of internal reset bail out
491	 * as the device is already setup
492	 */
493	cl = mei_cl_bus_find_cl_by_uuid(dev, mei_nfc_guid);
494	if (cl)
495		return 0;
496
497	ndev = kzalloc(sizeof(struct mei_nfc_dev), GFP_KERNEL);
498	if (!ndev) {
499		ret = -ENOMEM;
500		goto err;
501	}
502
503	/* check for valid client id */
504	me_cl = mei_me_cl_by_uuid(dev, &mei_nfc_info_guid);
505	if (!me_cl) {
506		dev_info(dev->dev, "nfc: failed to find the client\n");
507		ret = -ENOTTY;
508		goto err;
509	}
510
511	cl_info = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY);
512	if (IS_ERR(cl_info)) {
513		ret = PTR_ERR(cl_info);
514		goto err;
515	}
516
517	cl_info->me_client_id = me_cl->client_id;
518	cl_info->cl_uuid = me_cl->props.protocol_name;
519	mei_me_cl_put(me_cl);
520	me_cl = NULL;
521
522	list_add_tail(&cl_info->device_link, &dev->device_list);
523
524	ndev->cl_info = cl_info;
525
526	/* check for valid client id */
527	me_cl = mei_me_cl_by_uuid(dev, &mei_nfc_guid);
528	if (!me_cl) {
529		dev_info(dev->dev, "nfc: failed to find the client\n");
530		ret = -ENOTTY;
531		goto err;
532	}
533
534	cl = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY);
535	if (IS_ERR(cl)) {
536		ret = PTR_ERR(cl);
537		goto err;
538	}
539
540	cl->me_client_id = me_cl->client_id;
541	cl->cl_uuid = me_cl->props.protocol_name;
542	mei_me_cl_put(me_cl);
543	me_cl = NULL;
544
545	list_add_tail(&cl->device_link, &dev->device_list);
546
547	ndev->cl = cl;
548
549	ndev->req_id = 1;
550
551	INIT_WORK(&ndev->init_work, mei_nfc_init);
552	init_waitqueue_head(&ndev->send_wq);
553	schedule_work(&ndev->init_work);
554
555	return 0;
556
557err:
558	mei_me_cl_put(me_cl);
559	mei_nfc_free(ndev);
560
561	return ret;
562}
563
564void mei_nfc_host_exit(struct mei_device *dev)
565{
566	struct mei_nfc_dev *ndev;
567	struct mei_cl *cl;
568	struct mei_cl_device *cldev;
569
570	cl = mei_cl_bus_find_cl_by_uuid(dev, mei_nfc_guid);
571	if (!cl)
572		return;
573
574	cldev = cl->device;
575	if (!cldev)
576		return;
577
578	ndev = (struct mei_nfc_dev *)cldev->priv_data;
579	if (ndev)
580		cancel_work_sync(&ndev->init_work);
581
582	cldev->priv_data = NULL;
583
584	mutex_lock(&dev->device_lock);
585	/* Need to remove the device here
586	 * since mei_nfc_free will unlink the clients
587	 */
588	mei_cl_remove_device(cldev);
589	mei_nfc_free(ndev);
590	mutex_unlock(&dev->device_lock);
591}
592
593
594