1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Generic driver for NXP NCI NFC chips
4  *
5  * Copyright (C) 2014  NXP Semiconductors  All rights reserved.
6  *
7  * Author: Clément Perrochaud <clement.perrochaud@nxp.com>
8  *
9  * Derived from PN544 device driver:
10  * Copyright (C) 2012  Intel Corporation. All rights reserved.
11  */
12 
13 #include <linux/completion.h>
14 #include <linux/firmware.h>
15 #include <linux/nfc.h>
16 #include <asm/unaligned.h>
17 
18 #include "nxp-nci.h"
19 
20 /* Crypto operations can take up to 30 seconds */
21 #define NXP_NCI_FW_ANSWER_TIMEOUT	msecs_to_jiffies(30000)
22 
23 #define NXP_NCI_FW_CMD_RESET		0xF0
24 #define NXP_NCI_FW_CMD_GETVERSION	0xF1
25 #define NXP_NCI_FW_CMD_CHECKINTEGRITY	0xE0
26 #define NXP_NCI_FW_CMD_WRITE		0xC0
27 #define NXP_NCI_FW_CMD_READ		0xA2
28 #define NXP_NCI_FW_CMD_GETSESSIONSTATE	0xF2
29 #define NXP_NCI_FW_CMD_LOG		0xA7
30 #define NXP_NCI_FW_CMD_FORCE		0xD0
31 #define NXP_NCI_FW_CMD_GET_DIE_ID	0xF4
32 
33 #define NXP_NCI_FW_CHUNK_FLAG	0x0400
34 
35 #define NXP_NCI_FW_RESULT_OK				0x00
36 #define NXP_NCI_FW_RESULT_INVALID_ADDR			0x01
37 #define NXP_NCI_FW_RESULT_GENERIC_ERROR			0x02
38 #define NXP_NCI_FW_RESULT_UNKNOWN_CMD			0x0B
39 #define NXP_NCI_FW_RESULT_ABORTED_CMD			0x0C
40 #define NXP_NCI_FW_RESULT_PLL_ERROR			0x0D
41 #define NXP_NCI_FW_RESULT_ADDR_RANGE_OFL_ERROR		0x1E
42 #define NXP_NCI_FW_RESULT_BUFFER_OFL_ERROR		0x1F
43 #define NXP_NCI_FW_RESULT_MEM_BSY			0x20
44 #define NXP_NCI_FW_RESULT_SIGNATURE_ERROR		0x21
45 #define NXP_NCI_FW_RESULT_FIRMWARE_VERSION_ERROR	0x24
46 #define NXP_NCI_FW_RESULT_PROTOCOL_ERROR		0x28
47 #define NXP_NCI_FW_RESULT_SFWU_DEGRADED			0x2A
48 #define NXP_NCI_FW_RESULT_PH_STATUS_FIRST_CHUNK		0x2D
49 #define NXP_NCI_FW_RESULT_PH_STATUS_NEXT_CHUNK		0x2E
50 #define NXP_NCI_FW_RESULT_PH_STATUS_INTERNAL_ERROR_5	0xC5
51 
nxp_nci_fw_work_complete(struct nxp_nci_info * info,int result)52 void nxp_nci_fw_work_complete(struct nxp_nci_info *info, int result)
53 {
54 	struct nxp_nci_fw_info *fw_info = &info->fw_info;
55 	int r;
56 
57 	if (info->phy_ops->set_mode) {
58 		r = info->phy_ops->set_mode(info->phy_id, NXP_NCI_MODE_COLD);
59 		if (r < 0 && result == 0)
60 			result = -r;
61 	}
62 
63 	info->mode = NXP_NCI_MODE_COLD;
64 
65 	if (fw_info->fw) {
66 		release_firmware(fw_info->fw);
67 		fw_info->fw = NULL;
68 	}
69 
70 	nfc_fw_download_done(info->ndev->nfc_dev, fw_info->name, (u32) -result);
71 }
72 
73 /* crc_ccitt cannot be used since it is computed MSB first and not LSB first */
nxp_nci_fw_crc(u8 const * buffer,size_t len)74 static u16 nxp_nci_fw_crc(u8 const *buffer, size_t len)
75 {
76 	u16 crc = 0xffff;
77 
78 	while (len--) {
79 		crc = ((crc >> 8) | (crc << 8)) ^ *buffer++;
80 		crc ^= (crc & 0xff) >> 4;
81 		crc ^= (crc & 0xff) << 12;
82 		crc ^= (crc & 0xff) << 5;
83 	}
84 
85 	return crc;
86 }
87 
nxp_nci_fw_send_chunk(struct nxp_nci_info * info)88 static int nxp_nci_fw_send_chunk(struct nxp_nci_info *info)
89 {
90 	struct nxp_nci_fw_info *fw_info = &info->fw_info;
91 	u16 header, crc;
92 	struct sk_buff *skb;
93 	size_t chunk_len;
94 	size_t remaining_len;
95 	int r;
96 
97 	skb = nci_skb_alloc(info->ndev, info->max_payload, GFP_KERNEL);
98 	if (!skb)
99 		return -ENOMEM;
100 
101 	chunk_len = info->max_payload - NXP_NCI_FW_HDR_LEN - NXP_NCI_FW_CRC_LEN;
102 	remaining_len = fw_info->frame_size - fw_info->written;
103 
104 	if (remaining_len > chunk_len) {
105 		header = NXP_NCI_FW_CHUNK_FLAG;
106 	} else {
107 		chunk_len = remaining_len;
108 		header = 0x0000;
109 	}
110 
111 	header |= chunk_len & NXP_NCI_FW_FRAME_LEN_MASK;
112 	put_unaligned_be16(header, skb_put(skb, NXP_NCI_FW_HDR_LEN));
113 
114 	skb_put_data(skb, fw_info->data + fw_info->written, chunk_len);
115 
116 	crc = nxp_nci_fw_crc(skb->data, chunk_len + NXP_NCI_FW_HDR_LEN);
117 	put_unaligned_be16(crc, skb_put(skb, NXP_NCI_FW_CRC_LEN));
118 
119 	r = info->phy_ops->write(info->phy_id, skb);
120 	if (r >= 0)
121 		r = chunk_len;
122 
123 	kfree_skb(skb);
124 
125 	return r;
126 }
127 
nxp_nci_fw_send(struct nxp_nci_info * info)128 static int nxp_nci_fw_send(struct nxp_nci_info *info)
129 {
130 	struct nxp_nci_fw_info *fw_info = &info->fw_info;
131 	long completion_rc;
132 	int r;
133 
134 	reinit_completion(&fw_info->cmd_completion);
135 
136 	if (fw_info->written == 0) {
137 		fw_info->frame_size = get_unaligned_be16(fw_info->data) &
138 				      NXP_NCI_FW_FRAME_LEN_MASK;
139 		fw_info->data += NXP_NCI_FW_HDR_LEN;
140 		fw_info->size -= NXP_NCI_FW_HDR_LEN;
141 	}
142 
143 	if (fw_info->frame_size > fw_info->size)
144 		return -EMSGSIZE;
145 
146 	r = nxp_nci_fw_send_chunk(info);
147 	if (r < 0)
148 		return r;
149 
150 	fw_info->written += r;
151 
152 	if (*fw_info->data == NXP_NCI_FW_CMD_RESET) {
153 		fw_info->cmd_result = 0;
154 		if (fw_info->fw)
155 			schedule_work(&fw_info->work);
156 	} else {
157 		completion_rc = wait_for_completion_interruptible_timeout(
158 			&fw_info->cmd_completion, NXP_NCI_FW_ANSWER_TIMEOUT);
159 		if (completion_rc == 0)
160 			return -ETIMEDOUT;
161 	}
162 
163 	return 0;
164 }
165 
nxp_nci_fw_work(struct work_struct * work)166 void nxp_nci_fw_work(struct work_struct *work)
167 {
168 	struct nxp_nci_info *info;
169 	struct nxp_nci_fw_info *fw_info;
170 	int r;
171 
172 	fw_info = container_of(work, struct nxp_nci_fw_info, work);
173 	info = container_of(fw_info, struct nxp_nci_info, fw_info);
174 
175 	mutex_lock(&info->info_lock);
176 
177 	r = fw_info->cmd_result;
178 	if (r < 0)
179 		goto exit_work;
180 
181 	if (fw_info->written == fw_info->frame_size) {
182 		fw_info->data += fw_info->frame_size;
183 		fw_info->size -= fw_info->frame_size;
184 		fw_info->written = 0;
185 	}
186 
187 	if (fw_info->size > 0)
188 		r = nxp_nci_fw_send(info);
189 
190 exit_work:
191 	if (r < 0 || fw_info->size == 0)
192 		nxp_nci_fw_work_complete(info, r);
193 	mutex_unlock(&info->info_lock);
194 }
195 
nxp_nci_fw_download(struct nci_dev * ndev,const char * firmware_name)196 int nxp_nci_fw_download(struct nci_dev *ndev, const char *firmware_name)
197 {
198 	struct nxp_nci_info *info = nci_get_drvdata(ndev);
199 	struct nxp_nci_fw_info *fw_info = &info->fw_info;
200 	int r;
201 
202 	mutex_lock(&info->info_lock);
203 
204 	if (!info->phy_ops->set_mode || !info->phy_ops->write) {
205 		r = -ENOTSUPP;
206 		goto fw_download_exit;
207 	}
208 
209 	if (!firmware_name || firmware_name[0] == '\0') {
210 		r = -EINVAL;
211 		goto fw_download_exit;
212 	}
213 
214 	strcpy(fw_info->name, firmware_name);
215 
216 	r = request_firmware(&fw_info->fw, firmware_name,
217 			     ndev->nfc_dev->dev.parent);
218 	if (r < 0)
219 		goto fw_download_exit;
220 
221 	r = info->phy_ops->set_mode(info->phy_id, NXP_NCI_MODE_FW);
222 	if (r < 0) {
223 		release_firmware(fw_info->fw);
224 		goto fw_download_exit;
225 	}
226 
227 	info->mode = NXP_NCI_MODE_FW;
228 
229 	fw_info->data = fw_info->fw->data;
230 	fw_info->size = fw_info->fw->size;
231 	fw_info->written = 0;
232 	fw_info->frame_size = 0;
233 	fw_info->cmd_result = 0;
234 
235 	schedule_work(&fw_info->work);
236 
237 fw_download_exit:
238 	mutex_unlock(&info->info_lock);
239 	return r;
240 }
241 
nxp_nci_fw_read_status(u8 stat)242 static int nxp_nci_fw_read_status(u8 stat)
243 {
244 	switch (stat) {
245 	case NXP_NCI_FW_RESULT_OK:
246 		return 0;
247 	case NXP_NCI_FW_RESULT_INVALID_ADDR:
248 		return -EINVAL;
249 	case NXP_NCI_FW_RESULT_UNKNOWN_CMD:
250 		return -EINVAL;
251 	case NXP_NCI_FW_RESULT_ABORTED_CMD:
252 		return -EMSGSIZE;
253 	case NXP_NCI_FW_RESULT_ADDR_RANGE_OFL_ERROR:
254 		return -EADDRNOTAVAIL;
255 	case NXP_NCI_FW_RESULT_BUFFER_OFL_ERROR:
256 		return -ENOBUFS;
257 	case NXP_NCI_FW_RESULT_MEM_BSY:
258 		return -ENOKEY;
259 	case NXP_NCI_FW_RESULT_SIGNATURE_ERROR:
260 		return -EKEYREJECTED;
261 	case NXP_NCI_FW_RESULT_FIRMWARE_VERSION_ERROR:
262 		return -EALREADY;
263 	case NXP_NCI_FW_RESULT_PROTOCOL_ERROR:
264 		return -EPROTO;
265 	case NXP_NCI_FW_RESULT_SFWU_DEGRADED:
266 		return -EHWPOISON;
267 	case NXP_NCI_FW_RESULT_PH_STATUS_FIRST_CHUNK:
268 		return 0;
269 	case NXP_NCI_FW_RESULT_PH_STATUS_NEXT_CHUNK:
270 		return 0;
271 	case NXP_NCI_FW_RESULT_PH_STATUS_INTERNAL_ERROR_5:
272 		return -EINVAL;
273 	default:
274 		return -EIO;
275 	}
276 }
277 
nxp_nci_fw_check_crc(struct sk_buff * skb)278 static u16 nxp_nci_fw_check_crc(struct sk_buff *skb)
279 {
280 	u16 crc, frame_crc;
281 	size_t len = skb->len - NXP_NCI_FW_CRC_LEN;
282 
283 	crc = nxp_nci_fw_crc(skb->data, len);
284 	frame_crc = get_unaligned_be16(skb->data + len);
285 
286 	return (crc ^ frame_crc);
287 }
288 
nxp_nci_fw_recv_frame(struct nci_dev * ndev,struct sk_buff * skb)289 void nxp_nci_fw_recv_frame(struct nci_dev *ndev, struct sk_buff *skb)
290 {
291 	struct nxp_nci_info *info = nci_get_drvdata(ndev);
292 	struct nxp_nci_fw_info *fw_info = &info->fw_info;
293 
294 	complete(&fw_info->cmd_completion);
295 
296 	if (skb) {
297 		if (nxp_nci_fw_check_crc(skb) != 0x00)
298 			fw_info->cmd_result = -EBADMSG;
299 		else
300 			fw_info->cmd_result = nxp_nci_fw_read_status(*(u8 *)skb_pull(skb, NXP_NCI_FW_HDR_LEN));
301 		kfree_skb(skb);
302 	} else {
303 		fw_info->cmd_result = -EIO;
304 	}
305 
306 	if (fw_info->fw)
307 		schedule_work(&fw_info->work);
308 }
309 EXPORT_SYMBOL(nxp_nci_fw_recv_frame);
310