xref: /linux/drivers/bluetooth/btrtl.c (revision 80d443e8876602be2c130f79c4de81e12e2a700d)
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 #define RTL_ROM_LMP_8822B	0x8822
37 
38 static int rtl_read_rom_version(struct hci_dev *hdev, u8 *version)
39 {
40 	struct rtl_rom_version_evt *rom_version;
41 	struct sk_buff *skb;
42 
43 	/* Read RTL ROM version command */
44 	skb = __hci_cmd_sync(hdev, 0xfc6d, 0, NULL, HCI_INIT_TIMEOUT);
45 	if (IS_ERR(skb)) {
46 		BT_ERR("%s: Read ROM version failed (%ld)",
47 		       hdev->name, PTR_ERR(skb));
48 		return PTR_ERR(skb);
49 	}
50 
51 	if (skb->len != sizeof(*rom_version)) {
52 		BT_ERR("%s: RTL version event length mismatch", hdev->name);
53 		kfree_skb(skb);
54 		return -EIO;
55 	}
56 
57 	rom_version = (struct rtl_rom_version_evt *)skb->data;
58 	BT_INFO("%s: rom_version status=%x version=%x",
59 		hdev->name, rom_version->status, rom_version->version);
60 
61 	*version = rom_version->version;
62 
63 	kfree_skb(skb);
64 	return 0;
65 }
66 
67 static int rtl8723b_parse_firmware(struct hci_dev *hdev, u16 lmp_subver,
68 				   const struct firmware *fw,
69 				   unsigned char **_buf)
70 {
71 	const u8 extension_sig[] = { 0x51, 0x04, 0xfd, 0x77 };
72 	struct rtl_epatch_header *epatch_info;
73 	unsigned char *buf;
74 	int i, ret, len;
75 	size_t min_size;
76 	u8 opcode, length, data, rom_version = 0;
77 	int project_id = -1;
78 	const unsigned char *fwptr, *chip_id_base;
79 	const unsigned char *patch_length_base, *patch_offset_base;
80 	u32 patch_offset = 0;
81 	u16 patch_length, num_patches;
82 	static const struct {
83 		__u16 lmp_subver;
84 		__u8 id;
85 	} project_id_to_lmp_subver[] = {
86 		{ RTL_ROM_LMP_8723A, 0 },
87 		{ RTL_ROM_LMP_8723B, 1 },
88 		{ RTL_ROM_LMP_8821A, 2 },
89 		{ RTL_ROM_LMP_8761A, 3 },
90 		{ RTL_ROM_LMP_8822B, 8 },
91 	};
92 
93 	ret = rtl_read_rom_version(hdev, &rom_version);
94 	if (ret)
95 		return ret;
96 
97 	min_size = sizeof(struct rtl_epatch_header) + sizeof(extension_sig) + 3;
98 	if (fw->size < min_size)
99 		return -EINVAL;
100 
101 	fwptr = fw->data + fw->size - sizeof(extension_sig);
102 	if (memcmp(fwptr, extension_sig, sizeof(extension_sig)) != 0) {
103 		BT_ERR("%s: extension section signature mismatch", hdev->name);
104 		return -EINVAL;
105 	}
106 
107 	/* Loop from the end of the firmware parsing instructions, until
108 	 * we find an instruction that identifies the "project ID" for the
109 	 * hardware supported by this firwmare file.
110 	 * Once we have that, we double-check that that project_id is suitable
111 	 * for the hardware we are working with.
112 	 */
113 	while (fwptr >= fw->data + (sizeof(struct rtl_epatch_header) + 3)) {
114 		opcode = *--fwptr;
115 		length = *--fwptr;
116 		data = *--fwptr;
117 
118 		BT_DBG("check op=%x len=%x data=%x", opcode, length, data);
119 
120 		if (opcode == 0xff) /* EOF */
121 			break;
122 
123 		if (length == 0) {
124 			BT_ERR("%s: found instruction with length 0",
125 			       hdev->name);
126 			return -EINVAL;
127 		}
128 
129 		if (opcode == 0 && length == 1) {
130 			project_id = data;
131 			break;
132 		}
133 
134 		fwptr -= length;
135 	}
136 
137 	if (project_id < 0) {
138 		BT_ERR("%s: failed to find version instruction", hdev->name);
139 		return -EINVAL;
140 	}
141 
142 	/* Find project_id in table */
143 	for (i = 0; i < ARRAY_SIZE(project_id_to_lmp_subver); i++) {
144 		if (project_id == project_id_to_lmp_subver[i].id)
145 			break;
146 	}
147 
148 	if (i >= ARRAY_SIZE(project_id_to_lmp_subver)) {
149 		BT_ERR("%s: unknown project id %d", hdev->name, project_id);
150 		return -EINVAL;
151 	}
152 
153 	if (lmp_subver != project_id_to_lmp_subver[i].lmp_subver) {
154 		BT_ERR("%s: firmware is for %x but this is a %x", hdev->name,
155 		       project_id_to_lmp_subver[i].lmp_subver, lmp_subver);
156 		return -EINVAL;
157 	}
158 
159 	epatch_info = (struct rtl_epatch_header *)fw->data;
160 	if (memcmp(epatch_info->signature, RTL_EPATCH_SIGNATURE, 8) != 0) {
161 		BT_ERR("%s: bad EPATCH signature", hdev->name);
162 		return -EINVAL;
163 	}
164 
165 	num_patches = le16_to_cpu(epatch_info->num_patches);
166 	BT_DBG("fw_version=%x, num_patches=%d",
167 	       le32_to_cpu(epatch_info->fw_version), num_patches);
168 
169 	/* After the rtl_epatch_header there is a funky patch metadata section.
170 	 * Assuming 2 patches, the layout is:
171 	 * ChipID1 ChipID2 PatchLength1 PatchLength2 PatchOffset1 PatchOffset2
172 	 *
173 	 * Find the right patch for this chip.
174 	 */
175 	min_size += 8 * num_patches;
176 	if (fw->size < min_size)
177 		return -EINVAL;
178 
179 	chip_id_base = fw->data + sizeof(struct rtl_epatch_header);
180 	patch_length_base = chip_id_base + (sizeof(u16) * num_patches);
181 	patch_offset_base = patch_length_base + (sizeof(u16) * num_patches);
182 	for (i = 0; i < num_patches; i++) {
183 		u16 chip_id = get_unaligned_le16(chip_id_base +
184 						 (i * sizeof(u16)));
185 		if (chip_id == rom_version + 1) {
186 			patch_length = get_unaligned_le16(patch_length_base +
187 							  (i * sizeof(u16)));
188 			patch_offset = get_unaligned_le32(patch_offset_base +
189 							  (i * sizeof(u32)));
190 			break;
191 		}
192 	}
193 
194 	if (!patch_offset) {
195 		BT_ERR("%s: didn't find patch for chip id %d",
196 		       hdev->name, rom_version);
197 		return -EINVAL;
198 	}
199 
200 	BT_DBG("length=%x offset=%x index %d", patch_length, patch_offset, i);
201 	min_size = patch_offset + patch_length;
202 	if (fw->size < min_size)
203 		return -EINVAL;
204 
205 	/* Copy the firmware into a new buffer and write the version at
206 	 * the end.
207 	 */
208 	len = patch_length;
209 	buf = kmemdup(fw->data + patch_offset, patch_length, GFP_KERNEL);
210 	if (!buf)
211 		return -ENOMEM;
212 
213 	memcpy(buf + patch_length - 4, &epatch_info->fw_version, 4);
214 
215 	*_buf = buf;
216 	return len;
217 }
218 
219 static int rtl_download_firmware(struct hci_dev *hdev,
220 				 const unsigned char *data, int fw_len)
221 {
222 	struct rtl_download_cmd *dl_cmd;
223 	int frag_num = fw_len / RTL_FRAG_LEN + 1;
224 	int frag_len = RTL_FRAG_LEN;
225 	int ret = 0;
226 	int i;
227 
228 	dl_cmd = kmalloc(sizeof(struct rtl_download_cmd), GFP_KERNEL);
229 	if (!dl_cmd)
230 		return -ENOMEM;
231 
232 	for (i = 0; i < frag_num; i++) {
233 		struct sk_buff *skb;
234 
235 		BT_DBG("download fw (%d/%d)", i, frag_num);
236 
237 		dl_cmd->index = i;
238 		if (i == (frag_num - 1)) {
239 			dl_cmd->index |= 0x80; /* data end */
240 			frag_len = fw_len % RTL_FRAG_LEN;
241 		}
242 		memcpy(dl_cmd->data, data, frag_len);
243 
244 		/* Send download command */
245 		skb = __hci_cmd_sync(hdev, 0xfc20, frag_len + 1, dl_cmd,
246 				     HCI_INIT_TIMEOUT);
247 		if (IS_ERR(skb)) {
248 			BT_ERR("%s: download fw command failed (%ld)",
249 			       hdev->name, PTR_ERR(skb));
250 			ret = -PTR_ERR(skb);
251 			goto out;
252 		}
253 
254 		if (skb->len != sizeof(struct rtl_download_response)) {
255 			BT_ERR("%s: download fw event length mismatch",
256 			       hdev->name);
257 			kfree_skb(skb);
258 			ret = -EIO;
259 			goto out;
260 		}
261 
262 		kfree_skb(skb);
263 		data += RTL_FRAG_LEN;
264 	}
265 
266 out:
267 	kfree(dl_cmd);
268 	return ret;
269 }
270 
271 static int rtl_load_config(struct hci_dev *hdev, const char *name, u8 **buff)
272 {
273 	const struct firmware *fw;
274 	int ret;
275 
276 	BT_INFO("%s: rtl: loading %s", hdev->name, name);
277 	ret = request_firmware(&fw, name, &hdev->dev);
278 	if (ret < 0) {
279 		BT_ERR("%s: Failed to load %s", hdev->name, name);
280 		return ret;
281 	}
282 
283 	ret = fw->size;
284 	*buff = kmemdup(fw->data, ret, GFP_KERNEL);
285 
286 	release_firmware(fw);
287 
288 	return ret;
289 }
290 
291 static int btrtl_setup_rtl8723a(struct hci_dev *hdev)
292 {
293 	const struct firmware *fw;
294 	int ret;
295 
296 	BT_INFO("%s: rtl: loading rtl_bt/rtl8723a_fw.bin", hdev->name);
297 	ret = request_firmware(&fw, "rtl_bt/rtl8723a_fw.bin", &hdev->dev);
298 	if (ret < 0) {
299 		BT_ERR("%s: Failed to load rtl_bt/rtl8723a_fw.bin", hdev->name);
300 		return ret;
301 	}
302 
303 	if (fw->size < 8) {
304 		ret = -EINVAL;
305 		goto out;
306 	}
307 
308 	/* Check that the firmware doesn't have the epatch signature
309 	 * (which is only for RTL8723B and newer).
310 	 */
311 	if (!memcmp(fw->data, RTL_EPATCH_SIGNATURE, 8)) {
312 		BT_ERR("%s: unexpected EPATCH signature!", hdev->name);
313 		ret = -EINVAL;
314 		goto out;
315 	}
316 
317 	ret = rtl_download_firmware(hdev, fw->data, fw->size);
318 
319 out:
320 	release_firmware(fw);
321 	return ret;
322 }
323 
324 static int btrtl_setup_rtl8723b(struct hci_dev *hdev, u16 lmp_subver,
325 				const char *fw_name)
326 {
327 	unsigned char *fw_data = NULL;
328 	const struct firmware *fw;
329 	int ret;
330 	int cfg_sz;
331 	u8 *cfg_buff = NULL;
332 	u8 *tbuff;
333 	char *cfg_name = NULL;
334 
335 	switch (lmp_subver) {
336 	case RTL_ROM_LMP_8723B:
337 		cfg_name = "rtl_bt/rtl8723b_config.bin";
338 		break;
339 	case RTL_ROM_LMP_8821A:
340 		cfg_name = "rtl_bt/rtl8821a_config.bin";
341 		break;
342 	case RTL_ROM_LMP_8761A:
343 		cfg_name = "rtl_bt/rtl8761a_config.bin";
344 		break;
345 	case RTL_ROM_LMP_8822B:
346 		cfg_name = "rtl_bt/rtl8822b_config.bin";
347 		break;
348 	default:
349 		BT_ERR("%s: rtl: no config according to lmp_subver %04x",
350 		       hdev->name, lmp_subver);
351 		break;
352 	}
353 
354 	if (cfg_name) {
355 		cfg_sz = rtl_load_config(hdev, cfg_name, &cfg_buff);
356 		if (cfg_sz < 0)
357 			cfg_sz = 0;
358 	} else
359 		cfg_sz = 0;
360 
361 	BT_INFO("%s: rtl: loading %s", hdev->name, fw_name);
362 	ret = request_firmware(&fw, fw_name, &hdev->dev);
363 	if (ret < 0) {
364 		BT_ERR("%s: Failed to load %s", hdev->name, fw_name);
365 		goto err_req_fw;
366 	}
367 
368 	ret = rtl8723b_parse_firmware(hdev, lmp_subver, fw, &fw_data);
369 	if (ret < 0)
370 		goto out;
371 
372 	if (cfg_sz) {
373 		tbuff = kzalloc(ret + cfg_sz, GFP_KERNEL);
374 		if (!tbuff) {
375 			ret = -ENOMEM;
376 			goto out;
377 		}
378 
379 		memcpy(tbuff, fw_data, ret);
380 		kfree(fw_data);
381 
382 		memcpy(tbuff + ret, cfg_buff, cfg_sz);
383 		ret += cfg_sz;
384 
385 		fw_data = tbuff;
386 	}
387 
388 	BT_INFO("cfg_sz %d, total size %d", cfg_sz, ret);
389 
390 	ret = rtl_download_firmware(hdev, fw_data, ret);
391 
392 out:
393 	release_firmware(fw);
394 	kfree(fw_data);
395 err_req_fw:
396 	if (cfg_sz)
397 		kfree(cfg_buff);
398 	return ret;
399 }
400 
401 static struct sk_buff *btrtl_read_local_version(struct hci_dev *hdev)
402 {
403 	struct sk_buff *skb;
404 
405 	skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
406 			     HCI_INIT_TIMEOUT);
407 	if (IS_ERR(skb)) {
408 		BT_ERR("%s: HCI_OP_READ_LOCAL_VERSION failed (%ld)",
409 		       hdev->name, PTR_ERR(skb));
410 		return skb;
411 	}
412 
413 	if (skb->len != sizeof(struct hci_rp_read_local_version)) {
414 		BT_ERR("%s: HCI_OP_READ_LOCAL_VERSION event length mismatch",
415 		       hdev->name);
416 		kfree_skb(skb);
417 		return ERR_PTR(-EIO);
418 	}
419 
420 	return skb;
421 }
422 
423 int btrtl_setup_realtek(struct hci_dev *hdev)
424 {
425 	struct sk_buff *skb;
426 	struct hci_rp_read_local_version *resp;
427 	u16 lmp_subver;
428 
429 	skb = btrtl_read_local_version(hdev);
430 	if (IS_ERR(skb))
431 		return -PTR_ERR(skb);
432 
433 	resp = (struct hci_rp_read_local_version *)skb->data;
434 	BT_INFO("%s: rtl: examining hci_ver=%02x hci_rev=%04x lmp_ver=%02x "
435 		"lmp_subver=%04x", hdev->name, resp->hci_ver, resp->hci_rev,
436 		resp->lmp_ver, resp->lmp_subver);
437 
438 	lmp_subver = le16_to_cpu(resp->lmp_subver);
439 	kfree_skb(skb);
440 
441 	/* Match a set of subver values that correspond to stock firmware,
442 	 * which is not compatible with standard btusb.
443 	 * If matched, upload an alternative firmware that does conform to
444 	 * standard btusb. Once that firmware is uploaded, the subver changes
445 	 * to a different value.
446 	 */
447 	switch (lmp_subver) {
448 	case RTL_ROM_LMP_8723A:
449 	case RTL_ROM_LMP_3499:
450 		return btrtl_setup_rtl8723a(hdev);
451 	case RTL_ROM_LMP_8723B:
452 		return btrtl_setup_rtl8723b(hdev, lmp_subver,
453 					    "rtl_bt/rtl8723b_fw.bin");
454 	case RTL_ROM_LMP_8821A:
455 		return btrtl_setup_rtl8723b(hdev, lmp_subver,
456 					    "rtl_bt/rtl8821a_fw.bin");
457 	case RTL_ROM_LMP_8761A:
458 		return btrtl_setup_rtl8723b(hdev, lmp_subver,
459 					    "rtl_bt/rtl8761a_fw.bin");
460 	case RTL_ROM_LMP_8822B:
461 		return btrtl_setup_rtl8723b(hdev, lmp_subver,
462 					    "rtl_bt/rtl8822b_fw.bin");
463 	default:
464 		BT_INFO("rtl: assuming no firmware upload needed.");
465 		return 0;
466 	}
467 }
468 EXPORT_SYMBOL_GPL(btrtl_setup_realtek);
469 
470 MODULE_AUTHOR("Daniel Drake <drake@endlessm.com>");
471 MODULE_DESCRIPTION("Bluetooth support for Realtek devices ver " VERSION);
472 MODULE_VERSION(VERSION);
473 MODULE_LICENSE("GPL");
474