xref: /linux/drivers/misc/mei/bus-fixup.c (revision 0883c2c06fb5bcf5b9e008270827e63c09a88c1e)
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 #include <linux/uuid.h>
24 
25 #include <linux/mei_cl_bus.h>
26 
27 #include "mei_dev.h"
28 #include "client.h"
29 
30 #define MEI_UUID_NFC_INFO UUID_LE(0xd2de1625, 0x382d, 0x417d, \
31 			0x48, 0xa4, 0xef, 0xab, 0xba, 0x8a, 0x12, 0x06)
32 
33 static const uuid_le mei_nfc_info_guid = MEI_UUID_NFC_INFO;
34 
35 #define MEI_UUID_NFC_HCI UUID_LE(0x0bb17a78, 0x2a8e, 0x4c50, \
36 			0x94, 0xd4, 0x50, 0x26, 0x67, 0x23, 0x77, 0x5c)
37 
38 #define MEI_UUID_WD UUID_LE(0x05B79A6F, 0x4628, 0x4D7F, \
39 			    0x89, 0x9D, 0xA9, 0x15, 0x14, 0xCB, 0x32, 0xAB)
40 
41 #define MEI_UUID_ANY NULL_UUID_LE
42 
43 /**
44  * number_of_connections - determine whether an client be on the bus
45  *    according number of connections
46  *    We support only clients:
47  *       1. with single connection
48  *       2. and fixed clients (max_number_of_connections == 0)
49  *
50  * @cldev: me clients device
51  */
52 static void number_of_connections(struct mei_cl_device *cldev)
53 {
54 	dev_dbg(&cldev->dev, "running hook %s\n", __func__);
55 
56 	if (cldev->me_cl->props.max_number_of_connections > 1)
57 		cldev->do_match = 0;
58 }
59 
60 /**
61  * blacklist - blacklist a client from the bus
62  *
63  * @cldev: me clients device
64  */
65 static void blacklist(struct mei_cl_device *cldev)
66 {
67 	dev_dbg(&cldev->dev, "running hook %s\n", __func__);
68 
69 	cldev->do_match = 0;
70 }
71 
72 /**
73  * mei_wd - wd client on the bus, change protocol version
74  *   as the API has changed.
75  *
76  * @cldev: me clients device
77  */
78 #if IS_ENABLED(CONFIG_INTEL_MEI_ME)
79 #include <linux/pci.h>
80 #include "hw-me-regs.h"
81 static void mei_wd(struct mei_cl_device *cldev)
82 {
83 	struct pci_dev *pdev = to_pci_dev(cldev->dev.parent);
84 
85 	dev_dbg(&cldev->dev, "running hook %s\n", __func__);
86 	if (pdev->device == MEI_DEV_ID_WPT_LP ||
87 	    pdev->device == MEI_DEV_ID_SPT ||
88 	    pdev->device == MEI_DEV_ID_SPT_H)
89 		cldev->me_cl->props.protocol_version = 0x2;
90 
91 	cldev->do_match = 1;
92 }
93 #else
94 static inline void mei_wd(struct mei_cl_device *cldev) {}
95 #endif /* CONFIG_INTEL_MEI_ME */
96 
97 struct mei_nfc_cmd {
98 	u8 command;
99 	u8 status;
100 	u16 req_id;
101 	u32 reserved;
102 	u16 data_size;
103 	u8 sub_command;
104 	u8 data[];
105 } __packed;
106 
107 struct mei_nfc_reply {
108 	u8 command;
109 	u8 status;
110 	u16 req_id;
111 	u32 reserved;
112 	u16 data_size;
113 	u8 sub_command;
114 	u8 reply_status;
115 	u8 data[];
116 } __packed;
117 
118 struct mei_nfc_if_version {
119 	u8 radio_version_sw[3];
120 	u8 reserved[3];
121 	u8 radio_version_hw[3];
122 	u8 i2c_addr;
123 	u8 fw_ivn;
124 	u8 vendor_id;
125 	u8 radio_type;
126 } __packed;
127 
128 
129 #define MEI_NFC_CMD_MAINTENANCE 0x00
130 #define MEI_NFC_SUBCMD_IF_VERSION 0x01
131 
132 /* Vendors */
133 #define MEI_NFC_VENDOR_INSIDE 0x00
134 #define MEI_NFC_VENDOR_NXP    0x01
135 
136 /* Radio types */
137 #define MEI_NFC_VENDOR_INSIDE_UREAD 0x00
138 #define MEI_NFC_VENDOR_NXP_PN544    0x01
139 
140 /**
141  * mei_nfc_if_version - get NFC interface version
142  *
143  * @cl: host client (nfc info)
144  * @ver: NFC interface version to be filled in
145  *
146  * Return: 0 on success; < 0 otherwise
147  */
148 static int mei_nfc_if_version(struct mei_cl *cl,
149 			      struct mei_nfc_if_version *ver)
150 {
151 	struct mei_device *bus;
152 	struct mei_nfc_cmd cmd = {
153 		.command = MEI_NFC_CMD_MAINTENANCE,
154 		.data_size = 1,
155 		.sub_command = MEI_NFC_SUBCMD_IF_VERSION,
156 	};
157 	struct mei_nfc_reply *reply = NULL;
158 	size_t if_version_length;
159 	int bytes_recv, ret;
160 
161 	bus = cl->dev;
162 
163 	WARN_ON(mutex_is_locked(&bus->device_lock));
164 
165 	ret = __mei_cl_send(cl, (u8 *)&cmd, sizeof(struct mei_nfc_cmd), 1);
166 	if (ret < 0) {
167 		dev_err(bus->dev, "Could not send IF version cmd\n");
168 		return ret;
169 	}
170 
171 	/* to be sure on the stack we alloc memory */
172 	if_version_length = sizeof(struct mei_nfc_reply) +
173 		sizeof(struct mei_nfc_if_version);
174 
175 	reply = kzalloc(if_version_length, GFP_KERNEL);
176 	if (!reply)
177 		return -ENOMEM;
178 
179 	ret = 0;
180 	bytes_recv = __mei_cl_recv(cl, (u8 *)reply, if_version_length);
181 	if (bytes_recv < 0 || bytes_recv < sizeof(struct mei_nfc_reply)) {
182 		dev_err(bus->dev, "Could not read IF version\n");
183 		ret = -EIO;
184 		goto err;
185 	}
186 
187 	memcpy(ver, reply->data, sizeof(struct mei_nfc_if_version));
188 
189 	dev_info(bus->dev, "NFC MEI VERSION: IVN 0x%x Vendor ID 0x%x Type 0x%x\n",
190 		ver->fw_ivn, ver->vendor_id, ver->radio_type);
191 
192 err:
193 	kfree(reply);
194 	return ret;
195 }
196 
197 /**
198  * mei_nfc_radio_name - derive nfc radio name from the interface version
199  *
200  * @ver: NFC radio version
201  *
202  * Return: radio name string
203  */
204 static const char *mei_nfc_radio_name(struct mei_nfc_if_version *ver)
205 {
206 
207 	if (ver->vendor_id == MEI_NFC_VENDOR_INSIDE) {
208 		if (ver->radio_type == MEI_NFC_VENDOR_INSIDE_UREAD)
209 			return "microread";
210 	}
211 
212 	if (ver->vendor_id == MEI_NFC_VENDOR_NXP) {
213 		if (ver->radio_type == MEI_NFC_VENDOR_NXP_PN544)
214 			return "pn544";
215 	}
216 
217 	return NULL;
218 }
219 
220 /**
221  * mei_nfc - The nfc fixup function. The function retrieves nfc radio
222  *    name and set is as device attribute so we can load
223  *    the proper device driver for it
224  *
225  * @cldev: me client device (nfc)
226  */
227 static void mei_nfc(struct mei_cl_device *cldev)
228 {
229 	struct mei_device *bus;
230 	struct mei_cl *cl;
231 	struct mei_me_client *me_cl = NULL;
232 	struct mei_nfc_if_version ver;
233 	const char *radio_name = NULL;
234 	int ret;
235 
236 	bus = cldev->bus;
237 
238 	dev_dbg(&cldev->dev, "running hook %s\n", __func__);
239 
240 	mutex_lock(&bus->device_lock);
241 	/* we need to connect to INFO GUID */
242 	cl = mei_cl_alloc_linked(bus);
243 	if (IS_ERR(cl)) {
244 		ret = PTR_ERR(cl);
245 		cl = NULL;
246 		dev_err(bus->dev, "nfc hook alloc failed %d\n", ret);
247 		goto out;
248 	}
249 
250 	me_cl = mei_me_cl_by_uuid(bus, &mei_nfc_info_guid);
251 	if (!me_cl) {
252 		ret = -ENOTTY;
253 		dev_err(bus->dev, "Cannot find nfc info %d\n", ret);
254 		goto out;
255 	}
256 
257 	ret = mei_cl_connect(cl, me_cl, NULL);
258 	if (ret < 0) {
259 		dev_err(&cldev->dev, "Can't connect to the NFC INFO ME ret = %d\n",
260 			ret);
261 		goto out;
262 	}
263 
264 	mutex_unlock(&bus->device_lock);
265 
266 	ret = mei_nfc_if_version(cl, &ver);
267 	if (ret)
268 		goto disconnect;
269 
270 	radio_name = mei_nfc_radio_name(&ver);
271 
272 	if (!radio_name) {
273 		ret = -ENOENT;
274 		dev_err(&cldev->dev, "Can't get the NFC interface version ret = %d\n",
275 			ret);
276 		goto disconnect;
277 	}
278 
279 	dev_dbg(bus->dev, "nfc radio %s\n", radio_name);
280 	strlcpy(cldev->name, radio_name, sizeof(cldev->name));
281 
282 disconnect:
283 	mutex_lock(&bus->device_lock);
284 	if (mei_cl_disconnect(cl) < 0)
285 		dev_err(bus->dev, "Can't disconnect the NFC INFO ME\n");
286 
287 	mei_cl_flush_queues(cl, NULL);
288 
289 out:
290 	mei_cl_unlink(cl);
291 	mutex_unlock(&bus->device_lock);
292 	mei_me_cl_put(me_cl);
293 	kfree(cl);
294 
295 	if (ret)
296 		cldev->do_match = 0;
297 
298 	dev_dbg(bus->dev, "end of fixup match = %d\n", cldev->do_match);
299 }
300 
301 #define MEI_FIXUP(_uuid, _hook) { _uuid, _hook }
302 
303 static struct mei_fixup {
304 
305 	const uuid_le uuid;
306 	void (*hook)(struct mei_cl_device *cldev);
307 } mei_fixups[] = {
308 	MEI_FIXUP(MEI_UUID_ANY, number_of_connections),
309 	MEI_FIXUP(MEI_UUID_NFC_INFO, blacklist),
310 	MEI_FIXUP(MEI_UUID_NFC_HCI, mei_nfc),
311 	MEI_FIXUP(MEI_UUID_WD, mei_wd),
312 };
313 
314 /**
315  * mei_cldev_fixup - run fixup handlers
316  *
317  * @cldev: me client device
318  */
319 void mei_cl_bus_dev_fixup(struct mei_cl_device *cldev)
320 {
321 	struct mei_fixup *f;
322 	const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
323 	int i;
324 
325 	for (i = 0; i < ARRAY_SIZE(mei_fixups); i++) {
326 
327 		f = &mei_fixups[i];
328 		if (uuid_le_cmp(f->uuid, MEI_UUID_ANY) == 0 ||
329 		    uuid_le_cmp(f->uuid, *uuid) == 0)
330 			f->hook(cldev);
331 	}
332 }
333 
334