1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Copyright (c) 2013, Intel Corporation. |
4 | * |
5 | * MEI Library for mei bus nfc device access |
6 | */ |
7 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
8 | |
9 | #include <linux/module.h> |
10 | #include <linux/slab.h> |
11 | #include <linux/nfc.h> |
12 | |
13 | #include "mei_phy.h" |
14 | |
15 | struct mei_nfc_hdr { |
16 | u8 cmd; |
17 | u8 status; |
18 | u16 req_id; |
19 | u32 reserved; |
20 | u16 data_size; |
21 | } __packed; |
22 | |
23 | struct mei_nfc_cmd { |
24 | struct mei_nfc_hdr hdr; |
25 | u8 sub_command; |
26 | u8 data[]; |
27 | } __packed; |
28 | |
29 | struct mei_nfc_reply { |
30 | struct mei_nfc_hdr hdr; |
31 | u8 sub_command; |
32 | u8 reply_status; |
33 | u8 data[]; |
34 | } __packed; |
35 | |
36 | struct mei_nfc_if_version { |
37 | u8 radio_version_sw[3]; |
38 | u8 reserved[3]; |
39 | u8 radio_version_hw[3]; |
40 | u8 i2c_addr; |
41 | u8 fw_ivn; |
42 | u8 vendor_id; |
43 | u8 radio_type; |
44 | } __packed; |
45 | |
46 | struct mei_nfc_connect { |
47 | u8 fw_ivn; |
48 | u8 vendor_id; |
49 | } __packed; |
50 | |
51 | struct mei_nfc_connect_resp { |
52 | u8 fw_ivn; |
53 | u8 vendor_id; |
54 | u16 me_major; |
55 | u16 me_minor; |
56 | u16 me_hotfix; |
57 | u16 me_build; |
58 | } __packed; |
59 | |
60 | |
61 | #define MEI_NFC_CMD_MAINTENANCE 0x00 |
62 | #define MEI_NFC_CMD_HCI_SEND 0x01 |
63 | #define MEI_NFC_CMD_HCI_RECV 0x02 |
64 | |
65 | #define MEI_NFC_SUBCMD_CONNECT 0x00 |
66 | #define MEI_NFC_SUBCMD_IF_VERSION 0x01 |
67 | |
68 | #define MEI_NFC_MAX_READ (MEI_NFC_HEADER_SIZE + MEI_NFC_MAX_HCI_PAYLOAD) |
69 | |
70 | #define MEI_DUMP_SKB_IN(info, skb) \ |
71 | do { \ |
72 | pr_debug("%s:\n", info); \ |
73 | print_hex_dump_debug("mei in : ", DUMP_PREFIX_OFFSET, \ |
74 | 16, 1, (skb)->data, (skb)->len, false); \ |
75 | } while (0) |
76 | |
77 | #define MEI_DUMP_SKB_OUT(info, skb) \ |
78 | do { \ |
79 | pr_debug("%s:\n", info); \ |
80 | print_hex_dump_debug("mei out: ", DUMP_PREFIX_OFFSET, \ |
81 | 16, 1, (skb)->data, (skb)->len, false); \ |
82 | } while (0) |
83 | |
84 | #define MEI_DUMP_NFC_HDR(info, _hdr) \ |
85 | do { \ |
86 | pr_debug("%s:\n", info); \ |
87 | pr_debug("cmd=%02d status=%d req_id=%d rsvd=%d size=%d\n", \ |
88 | (_hdr)->cmd, (_hdr)->status, (_hdr)->req_id, \ |
89 | (_hdr)->reserved, (_hdr)->data_size); \ |
90 | } while (0) |
91 | |
92 | static int mei_nfc_if_version(struct nfc_mei_phy *phy) |
93 | { |
94 | |
95 | struct mei_nfc_cmd cmd; |
96 | struct mei_nfc_reply *reply = NULL; |
97 | struct mei_nfc_if_version *version; |
98 | size_t if_version_length; |
99 | int bytes_recv, r; |
100 | |
101 | memset(&cmd, 0, sizeof(struct mei_nfc_cmd)); |
102 | cmd.hdr.cmd = MEI_NFC_CMD_MAINTENANCE; |
103 | cmd.hdr.data_size = 1; |
104 | cmd.sub_command = MEI_NFC_SUBCMD_IF_VERSION; |
105 | |
106 | MEI_DUMP_NFC_HDR("version" , &cmd.hdr); |
107 | r = mei_cldev_send(cldev: phy->cldev, buf: (u8 *)&cmd, length: sizeof(struct mei_nfc_cmd)); |
108 | if (r < 0) { |
109 | pr_err("Could not send IF version cmd\n" ); |
110 | return r; |
111 | } |
112 | |
113 | /* to be sure on the stack we alloc memory */ |
114 | if_version_length = sizeof(struct mei_nfc_reply) + |
115 | sizeof(struct mei_nfc_if_version); |
116 | |
117 | reply = kzalloc(size: if_version_length, GFP_KERNEL); |
118 | if (!reply) |
119 | return -ENOMEM; |
120 | |
121 | bytes_recv = mei_cldev_recv(cldev: phy->cldev, buf: (u8 *)reply, length: if_version_length); |
122 | if (bytes_recv < 0 || bytes_recv < if_version_length) { |
123 | pr_err("Could not read IF version\n" ); |
124 | r = -EIO; |
125 | goto err; |
126 | } |
127 | |
128 | version = (struct mei_nfc_if_version *)reply->data; |
129 | |
130 | phy->fw_ivn = version->fw_ivn; |
131 | phy->vendor_id = version->vendor_id; |
132 | phy->radio_type = version->radio_type; |
133 | |
134 | err: |
135 | kfree(objp: reply); |
136 | return r; |
137 | } |
138 | |
139 | static int mei_nfc_connect(struct nfc_mei_phy *phy) |
140 | { |
141 | struct mei_nfc_cmd *cmd, *reply; |
142 | struct mei_nfc_connect *connect; |
143 | struct mei_nfc_connect_resp *connect_resp; |
144 | size_t connect_length, connect_resp_length; |
145 | int bytes_recv, r; |
146 | |
147 | connect_length = sizeof(struct mei_nfc_cmd) + |
148 | sizeof(struct mei_nfc_connect); |
149 | |
150 | connect_resp_length = sizeof(struct mei_nfc_cmd) + |
151 | sizeof(struct mei_nfc_connect_resp); |
152 | |
153 | cmd = kzalloc(size: connect_length, GFP_KERNEL); |
154 | if (!cmd) |
155 | return -ENOMEM; |
156 | connect = (struct mei_nfc_connect *)cmd->data; |
157 | |
158 | reply = kzalloc(size: connect_resp_length, GFP_KERNEL); |
159 | if (!reply) { |
160 | kfree(objp: cmd); |
161 | return -ENOMEM; |
162 | } |
163 | |
164 | connect_resp = (struct mei_nfc_connect_resp *)reply->data; |
165 | |
166 | cmd->hdr.cmd = MEI_NFC_CMD_MAINTENANCE; |
167 | cmd->hdr.data_size = 3; |
168 | cmd->sub_command = MEI_NFC_SUBCMD_CONNECT; |
169 | connect->fw_ivn = phy->fw_ivn; |
170 | connect->vendor_id = phy->vendor_id; |
171 | |
172 | MEI_DUMP_NFC_HDR("connect request" , &cmd->hdr); |
173 | r = mei_cldev_send(cldev: phy->cldev, buf: (u8 *)cmd, length: connect_length); |
174 | if (r < 0) { |
175 | pr_err("Could not send connect cmd %d\n" , r); |
176 | goto err; |
177 | } |
178 | |
179 | bytes_recv = mei_cldev_recv(cldev: phy->cldev, buf: (u8 *)reply, |
180 | length: connect_resp_length); |
181 | if (bytes_recv < 0) { |
182 | r = bytes_recv; |
183 | pr_err("Could not read connect response %d\n" , r); |
184 | goto err; |
185 | } |
186 | |
187 | MEI_DUMP_NFC_HDR("connect reply" , &reply->hdr); |
188 | |
189 | pr_info("IVN 0x%x Vendor ID 0x%x\n" , |
190 | connect_resp->fw_ivn, connect_resp->vendor_id); |
191 | |
192 | pr_info("ME FW %d.%d.%d.%d\n" , |
193 | connect_resp->me_major, connect_resp->me_minor, |
194 | connect_resp->me_hotfix, connect_resp->me_build); |
195 | |
196 | r = 0; |
197 | |
198 | err: |
199 | kfree(objp: reply); |
200 | kfree(objp: cmd); |
201 | |
202 | return r; |
203 | } |
204 | |
205 | static int mei_nfc_send(struct nfc_mei_phy *phy, const u8 *buf, size_t length) |
206 | { |
207 | struct mei_nfc_hdr *hdr; |
208 | u8 *mei_buf; |
209 | int err; |
210 | |
211 | err = -ENOMEM; |
212 | mei_buf = kzalloc(size: length + MEI_NFC_HEADER_SIZE, GFP_KERNEL); |
213 | if (!mei_buf) |
214 | goto out; |
215 | |
216 | hdr = (struct mei_nfc_hdr *)mei_buf; |
217 | hdr->cmd = MEI_NFC_CMD_HCI_SEND; |
218 | hdr->status = 0; |
219 | hdr->req_id = phy->req_id; |
220 | hdr->reserved = 0; |
221 | hdr->data_size = length; |
222 | |
223 | MEI_DUMP_NFC_HDR("send" , hdr); |
224 | |
225 | memcpy(mei_buf + MEI_NFC_HEADER_SIZE, buf, length); |
226 | err = mei_cldev_send(cldev: phy->cldev, buf: mei_buf, length: length + MEI_NFC_HEADER_SIZE); |
227 | if (err < 0) |
228 | goto out; |
229 | |
230 | if (!wait_event_interruptible_timeout(phy->send_wq, |
231 | phy->recv_req_id == phy->req_id, HZ)) { |
232 | pr_err("NFC MEI command timeout\n" ); |
233 | err = -ETIME; |
234 | } else { |
235 | phy->req_id++; |
236 | } |
237 | out: |
238 | kfree(objp: mei_buf); |
239 | return err; |
240 | } |
241 | |
242 | /* |
243 | * Writing a frame must not return the number of written bytes. |
244 | * It must return either zero for success, or <0 for error. |
245 | * In addition, it must not alter the skb |
246 | */ |
247 | static int nfc_mei_phy_write(void *phy_id, struct sk_buff *skb) |
248 | { |
249 | struct nfc_mei_phy *phy = phy_id; |
250 | int r; |
251 | |
252 | MEI_DUMP_SKB_OUT("mei frame sent" , skb); |
253 | |
254 | r = mei_nfc_send(phy, buf: skb->data, length: skb->len); |
255 | if (r > 0) |
256 | r = 0; |
257 | |
258 | return r; |
259 | } |
260 | |
261 | static int mei_nfc_recv(struct nfc_mei_phy *phy, u8 *buf, size_t length) |
262 | { |
263 | struct mei_nfc_hdr *hdr; |
264 | int received_length; |
265 | |
266 | received_length = mei_cldev_recv(cldev: phy->cldev, buf, length); |
267 | if (received_length < 0) |
268 | return received_length; |
269 | |
270 | hdr = (struct mei_nfc_hdr *) buf; |
271 | |
272 | MEI_DUMP_NFC_HDR("receive" , hdr); |
273 | if (hdr->cmd == MEI_NFC_CMD_HCI_SEND) { |
274 | phy->recv_req_id = hdr->req_id; |
275 | wake_up(&phy->send_wq); |
276 | |
277 | return 0; |
278 | } |
279 | |
280 | return received_length; |
281 | } |
282 | |
283 | |
284 | static void nfc_mei_rx_cb(struct mei_cl_device *cldev) |
285 | { |
286 | struct nfc_mei_phy *phy = mei_cldev_get_drvdata(cldev); |
287 | struct sk_buff *skb; |
288 | int reply_size; |
289 | |
290 | if (!phy) |
291 | return; |
292 | |
293 | if (phy->hard_fault != 0) |
294 | return; |
295 | |
296 | skb = alloc_skb(MEI_NFC_MAX_READ, GFP_KERNEL); |
297 | if (!skb) |
298 | return; |
299 | |
300 | reply_size = mei_nfc_recv(phy, buf: skb->data, MEI_NFC_MAX_READ); |
301 | if (reply_size < MEI_NFC_HEADER_SIZE) { |
302 | kfree_skb(skb); |
303 | return; |
304 | } |
305 | |
306 | skb_put(skb, len: reply_size); |
307 | skb_pull(skb, MEI_NFC_HEADER_SIZE); |
308 | |
309 | MEI_DUMP_SKB_IN("mei frame read" , skb); |
310 | |
311 | nfc_hci_recv_frame(hdev: phy->hdev, skb); |
312 | } |
313 | |
314 | static int nfc_mei_phy_enable(void *phy_id) |
315 | { |
316 | int r; |
317 | struct nfc_mei_phy *phy = phy_id; |
318 | |
319 | if (phy->powered == 1) |
320 | return 0; |
321 | |
322 | r = mei_cldev_enable(cldev: phy->cldev); |
323 | if (r < 0) { |
324 | pr_err("Could not enable device %d\n" , r); |
325 | return r; |
326 | } |
327 | |
328 | r = mei_nfc_if_version(phy); |
329 | if (r < 0) { |
330 | pr_err("Could not enable device %d\n" , r); |
331 | goto err; |
332 | } |
333 | |
334 | r = mei_nfc_connect(phy); |
335 | if (r < 0) { |
336 | pr_err("Could not connect to device %d\n" , r); |
337 | goto err; |
338 | } |
339 | |
340 | r = mei_cldev_register_rx_cb(cldev: phy->cldev, rx_cb: nfc_mei_rx_cb); |
341 | if (r) { |
342 | pr_err("Event cb registration failed %d\n" , r); |
343 | goto err; |
344 | } |
345 | |
346 | phy->powered = 1; |
347 | |
348 | return 0; |
349 | |
350 | err: |
351 | phy->powered = 0; |
352 | mei_cldev_disable(cldev: phy->cldev); |
353 | return r; |
354 | } |
355 | |
356 | static void nfc_mei_phy_disable(void *phy_id) |
357 | { |
358 | struct nfc_mei_phy *phy = phy_id; |
359 | |
360 | mei_cldev_disable(cldev: phy->cldev); |
361 | |
362 | phy->powered = 0; |
363 | } |
364 | |
365 | const struct nfc_phy_ops mei_phy_ops = { |
366 | .write = nfc_mei_phy_write, |
367 | .enable = nfc_mei_phy_enable, |
368 | .disable = nfc_mei_phy_disable, |
369 | }; |
370 | EXPORT_SYMBOL_GPL(mei_phy_ops); |
371 | |
372 | struct nfc_mei_phy *nfc_mei_phy_alloc(struct mei_cl_device *cldev) |
373 | { |
374 | struct nfc_mei_phy *phy; |
375 | |
376 | phy = kzalloc(size: sizeof(struct nfc_mei_phy), GFP_KERNEL); |
377 | if (!phy) |
378 | return NULL; |
379 | |
380 | phy->cldev = cldev; |
381 | init_waitqueue_head(&phy->send_wq); |
382 | mei_cldev_set_drvdata(cldev, data: phy); |
383 | |
384 | return phy; |
385 | } |
386 | EXPORT_SYMBOL_GPL(nfc_mei_phy_alloc); |
387 | |
388 | void nfc_mei_phy_free(struct nfc_mei_phy *phy) |
389 | { |
390 | mei_cldev_disable(cldev: phy->cldev); |
391 | kfree(objp: phy); |
392 | } |
393 | EXPORT_SYMBOL_GPL(nfc_mei_phy_free); |
394 | |
395 | MODULE_LICENSE("GPL" ); |
396 | MODULE_DESCRIPTION("mei bus NFC device interface" ); |
397 | |