1 /*
2 * Bluetooth support for Realtek devices
3 *
4 * Copyright (C) 2015 Endless Mobile, Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 */
17
18 #include <linux/module.h>
19 #include <linux/firmware.h>
20 #include <asm/unaligned.h>
21 #include <linux/usb.h>
22
23 #include <net/bluetooth/bluetooth.h>
24 #include <net/bluetooth/hci_core.h>
25
26 #include "btrtl.h"
27
28 #define VERSION "0.1"
29
30 #define RTL_EPATCH_SIGNATURE "Realtech"
31 #define RTL_ROM_LMP_3499 0x3499
32 #define RTL_ROM_LMP_8723A 0x1200
33 #define RTL_ROM_LMP_8723B 0x8723
34 #define RTL_ROM_LMP_8821A 0x8821
35 #define RTL_ROM_LMP_8761A 0x8761
36
rtl_read_rom_version(struct hci_dev * hdev,u8 * version)37 static int rtl_read_rom_version(struct hci_dev *hdev, u8 *version)
38 {
39 struct rtl_rom_version_evt *rom_version;
40 struct sk_buff *skb;
41
42 /* Read RTL ROM version command */
43 skb = __hci_cmd_sync(hdev, 0xfc6d, 0, NULL, HCI_INIT_TIMEOUT);
44 if (IS_ERR(skb)) {
45 BT_ERR("%s: Read ROM version failed (%ld)",
46 hdev->name, PTR_ERR(skb));
47 return PTR_ERR(skb);
48 }
49
50 if (skb->len != sizeof(*rom_version)) {
51 BT_ERR("%s: RTL version event length mismatch", hdev->name);
52 kfree_skb(skb);
53 return -EIO;
54 }
55
56 rom_version = (struct rtl_rom_version_evt *)skb->data;
57 BT_INFO("%s: rom_version status=%x version=%x",
58 hdev->name, rom_version->status, rom_version->version);
59
60 *version = rom_version->version;
61
62 kfree_skb(skb);
63 return 0;
64 }
65
rtl8723b_parse_firmware(struct hci_dev * hdev,u16 lmp_subver,const struct firmware * fw,unsigned char ** _buf)66 static int rtl8723b_parse_firmware(struct hci_dev *hdev, u16 lmp_subver,
67 const struct firmware *fw,
68 unsigned char **_buf)
69 {
70 const u8 extension_sig[] = { 0x51, 0x04, 0xfd, 0x77 };
71 struct rtl_epatch_header *epatch_info;
72 unsigned char *buf;
73 int i, ret, len;
74 size_t min_size;
75 u8 opcode, length, data, rom_version = 0;
76 int project_id = -1;
77 const unsigned char *fwptr, *chip_id_base;
78 const unsigned char *patch_length_base, *patch_offset_base;
79 u32 patch_offset = 0;
80 u16 patch_length, num_patches;
81 const u16 project_id_to_lmp_subver[] = {
82 RTL_ROM_LMP_8723A,
83 RTL_ROM_LMP_8723B,
84 RTL_ROM_LMP_8821A,
85 RTL_ROM_LMP_8761A
86 };
87
88 ret = rtl_read_rom_version(hdev, &rom_version);
89 if (ret)
90 return ret;
91
92 min_size = sizeof(struct rtl_epatch_header) + sizeof(extension_sig) + 3;
93 if (fw->size < min_size)
94 return -EINVAL;
95
96 fwptr = fw->data + fw->size - sizeof(extension_sig);
97 if (memcmp(fwptr, extension_sig, sizeof(extension_sig)) != 0) {
98 BT_ERR("%s: extension section signature mismatch", hdev->name);
99 return -EINVAL;
100 }
101
102 /* Loop from the end of the firmware parsing instructions, until
103 * we find an instruction that identifies the "project ID" for the
104 * hardware supported by this firwmare file.
105 * Once we have that, we double-check that that project_id is suitable
106 * for the hardware we are working with.
107 */
108 while (fwptr >= fw->data + (sizeof(struct rtl_epatch_header) + 3)) {
109 opcode = *--fwptr;
110 length = *--fwptr;
111 data = *--fwptr;
112
113 BT_DBG("check op=%x len=%x data=%x", opcode, length, data);
114
115 if (opcode == 0xff) /* EOF */
116 break;
117
118 if (length == 0) {
119 BT_ERR("%s: found instruction with length 0",
120 hdev->name);
121 return -EINVAL;
122 }
123
124 if (opcode == 0 && length == 1) {
125 project_id = data;
126 break;
127 }
128
129 fwptr -= length;
130 }
131
132 if (project_id < 0) {
133 BT_ERR("%s: failed to find version instruction", hdev->name);
134 return -EINVAL;
135 }
136
137 if (project_id >= ARRAY_SIZE(project_id_to_lmp_subver)) {
138 BT_ERR("%s: unknown project id %d", hdev->name, project_id);
139 return -EINVAL;
140 }
141
142 if (lmp_subver != project_id_to_lmp_subver[project_id]) {
143 BT_ERR("%s: firmware is for %x but this is a %x", hdev->name,
144 project_id_to_lmp_subver[project_id], lmp_subver);
145 return -EINVAL;
146 }
147
148 epatch_info = (struct rtl_epatch_header *)fw->data;
149 if (memcmp(epatch_info->signature, RTL_EPATCH_SIGNATURE, 8) != 0) {
150 BT_ERR("%s: bad EPATCH signature", hdev->name);
151 return -EINVAL;
152 }
153
154 num_patches = le16_to_cpu(epatch_info->num_patches);
155 BT_DBG("fw_version=%x, num_patches=%d",
156 le32_to_cpu(epatch_info->fw_version), num_patches);
157
158 /* After the rtl_epatch_header there is a funky patch metadata section.
159 * Assuming 2 patches, the layout is:
160 * ChipID1 ChipID2 PatchLength1 PatchLength2 PatchOffset1 PatchOffset2
161 *
162 * Find the right patch for this chip.
163 */
164 min_size += 8 * num_patches;
165 if (fw->size < min_size)
166 return -EINVAL;
167
168 chip_id_base = fw->data + sizeof(struct rtl_epatch_header);
169 patch_length_base = chip_id_base + (sizeof(u16) * num_patches);
170 patch_offset_base = patch_length_base + (sizeof(u16) * num_patches);
171 for (i = 0; i < num_patches; i++) {
172 u16 chip_id = get_unaligned_le16(chip_id_base +
173 (i * sizeof(u16)));
174 if (chip_id == rom_version + 1) {
175 patch_length = get_unaligned_le16(patch_length_base +
176 (i * sizeof(u16)));
177 patch_offset = get_unaligned_le32(patch_offset_base +
178 (i * sizeof(u32)));
179 break;
180 }
181 }
182
183 if (!patch_offset) {
184 BT_ERR("%s: didn't find patch for chip id %d",
185 hdev->name, rom_version);
186 return -EINVAL;
187 }
188
189 BT_DBG("length=%x offset=%x index %d", patch_length, patch_offset, i);
190 min_size = patch_offset + patch_length;
191 if (fw->size < min_size)
192 return -EINVAL;
193
194 /* Copy the firmware into a new buffer and write the version at
195 * the end.
196 */
197 len = patch_length;
198 buf = kmemdup(fw->data + patch_offset, patch_length, GFP_KERNEL);
199 if (!buf)
200 return -ENOMEM;
201
202 memcpy(buf + patch_length - 4, &epatch_info->fw_version, 4);
203
204 *_buf = buf;
205 return len;
206 }
207
rtl_download_firmware(struct hci_dev * hdev,const unsigned char * data,int fw_len)208 static int rtl_download_firmware(struct hci_dev *hdev,
209 const unsigned char *data, int fw_len)
210 {
211 struct rtl_download_cmd *dl_cmd;
212 int frag_num = fw_len / RTL_FRAG_LEN + 1;
213 int frag_len = RTL_FRAG_LEN;
214 int ret = 0;
215 int i;
216
217 dl_cmd = kmalloc(sizeof(struct rtl_download_cmd), GFP_KERNEL);
218 if (!dl_cmd)
219 return -ENOMEM;
220
221 for (i = 0; i < frag_num; i++) {
222 struct sk_buff *skb;
223
224 BT_DBG("download fw (%d/%d)", i, frag_num);
225
226 dl_cmd->index = i;
227 if (i == (frag_num - 1)) {
228 dl_cmd->index |= 0x80; /* data end */
229 frag_len = fw_len % RTL_FRAG_LEN;
230 }
231 memcpy(dl_cmd->data, data, frag_len);
232
233 /* Send download command */
234 skb = __hci_cmd_sync(hdev, 0xfc20, frag_len + 1, dl_cmd,
235 HCI_INIT_TIMEOUT);
236 if (IS_ERR(skb)) {
237 BT_ERR("%s: download fw command failed (%ld)",
238 hdev->name, PTR_ERR(skb));
239 ret = -PTR_ERR(skb);
240 goto out;
241 }
242
243 if (skb->len != sizeof(struct rtl_download_response)) {
244 BT_ERR("%s: download fw event length mismatch",
245 hdev->name);
246 kfree_skb(skb);
247 ret = -EIO;
248 goto out;
249 }
250
251 kfree_skb(skb);
252 data += RTL_FRAG_LEN;
253 }
254
255 out:
256 kfree(dl_cmd);
257 return ret;
258 }
259
btrtl_setup_rtl8723a(struct hci_dev * hdev)260 static int btrtl_setup_rtl8723a(struct hci_dev *hdev)
261 {
262 const struct firmware *fw;
263 int ret;
264
265 BT_INFO("%s: rtl: loading rtl_bt/rtl8723a_fw.bin", hdev->name);
266 ret = request_firmware(&fw, "rtl_bt/rtl8723a_fw.bin", &hdev->dev);
267 if (ret < 0) {
268 BT_ERR("%s: Failed to load rtl_bt/rtl8723a_fw.bin", hdev->name);
269 return ret;
270 }
271
272 if (fw->size < 8) {
273 ret = -EINVAL;
274 goto out;
275 }
276
277 /* Check that the firmware doesn't have the epatch signature
278 * (which is only for RTL8723B and newer).
279 */
280 if (!memcmp(fw->data, RTL_EPATCH_SIGNATURE, 8)) {
281 BT_ERR("%s: unexpected EPATCH signature!", hdev->name);
282 ret = -EINVAL;
283 goto out;
284 }
285
286 ret = rtl_download_firmware(hdev, fw->data, fw->size);
287
288 out:
289 release_firmware(fw);
290 return ret;
291 }
292
btrtl_setup_rtl8723b(struct hci_dev * hdev,u16 lmp_subver,const char * fw_name)293 static int btrtl_setup_rtl8723b(struct hci_dev *hdev, u16 lmp_subver,
294 const char *fw_name)
295 {
296 unsigned char *fw_data = NULL;
297 const struct firmware *fw;
298 int ret;
299
300 BT_INFO("%s: rtl: loading %s", hdev->name, fw_name);
301 ret = request_firmware(&fw, fw_name, &hdev->dev);
302 if (ret < 0) {
303 BT_ERR("%s: Failed to load %s", hdev->name, fw_name);
304 return ret;
305 }
306
307 ret = rtl8723b_parse_firmware(hdev, lmp_subver, fw, &fw_data);
308 if (ret < 0)
309 goto out;
310
311 ret = rtl_download_firmware(hdev, fw_data, ret);
312 kfree(fw_data);
313 if (ret < 0)
314 goto out;
315
316 out:
317 release_firmware(fw);
318 return ret;
319 }
320
btrtl_read_local_version(struct hci_dev * hdev)321 static struct sk_buff *btrtl_read_local_version(struct hci_dev *hdev)
322 {
323 struct sk_buff *skb;
324
325 skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
326 HCI_INIT_TIMEOUT);
327 if (IS_ERR(skb)) {
328 BT_ERR("%s: HCI_OP_READ_LOCAL_VERSION failed (%ld)",
329 hdev->name, PTR_ERR(skb));
330 return skb;
331 }
332
333 if (skb->len != sizeof(struct hci_rp_read_local_version)) {
334 BT_ERR("%s: HCI_OP_READ_LOCAL_VERSION event length mismatch",
335 hdev->name);
336 kfree_skb(skb);
337 return ERR_PTR(-EIO);
338 }
339
340 return skb;
341 }
342
btrtl_setup_realtek(struct hci_dev * hdev)343 int btrtl_setup_realtek(struct hci_dev *hdev)
344 {
345 struct sk_buff *skb;
346 struct hci_rp_read_local_version *resp;
347 u16 lmp_subver;
348
349 skb = btrtl_read_local_version(hdev);
350 if (IS_ERR(skb))
351 return -PTR_ERR(skb);
352
353 resp = (struct hci_rp_read_local_version *)skb->data;
354 BT_INFO("%s: rtl: examining hci_ver=%02x hci_rev=%04x lmp_ver=%02x "
355 "lmp_subver=%04x", hdev->name, resp->hci_ver, resp->hci_rev,
356 resp->lmp_ver, resp->lmp_subver);
357
358 lmp_subver = le16_to_cpu(resp->lmp_subver);
359 kfree_skb(skb);
360
361 /* Match a set of subver values that correspond to stock firmware,
362 * which is not compatible with standard btusb.
363 * If matched, upload an alternative firmware that does conform to
364 * standard btusb. Once that firmware is uploaded, the subver changes
365 * to a different value.
366 */
367 switch (lmp_subver) {
368 case RTL_ROM_LMP_8723A:
369 case RTL_ROM_LMP_3499:
370 return btrtl_setup_rtl8723a(hdev);
371 case RTL_ROM_LMP_8723B:
372 return btrtl_setup_rtl8723b(hdev, lmp_subver,
373 "rtl_bt/rtl8723b_fw.bin");
374 case RTL_ROM_LMP_8821A:
375 return btrtl_setup_rtl8723b(hdev, lmp_subver,
376 "rtl_bt/rtl8821a_fw.bin");
377 case RTL_ROM_LMP_8761A:
378 return btrtl_setup_rtl8723b(hdev, lmp_subver,
379 "rtl_bt/rtl8761a_fw.bin");
380 default:
381 BT_INFO("rtl: assuming no firmware upload needed.");
382 return 0;
383 }
384 }
385 EXPORT_SYMBOL_GPL(btrtl_setup_realtek);
386
387 MODULE_AUTHOR("Daniel Drake <drake@endlessm.com>");
388 MODULE_DESCRIPTION("Bluetooth support for Realtek devices ver " VERSION);
389 MODULE_VERSION(VERSION);
390 MODULE_LICENSE("GPL");
391