summaryrefslogtreecommitdiffstats
path: root/drivers/bluetooth/btrtl.c
blob: 84288938f7f2c261e312afaa505564a4f749b3b1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
/*
 *  Bluetooth support for Realtek devices
 *
 *  Copyright (C) 2015 Endless Mobile, Inc.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 */

#include <linux/module.h>
#include <linux/firmware.h>
#include <asm/unaligned.h>
#include <linux/usb.h>

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>

#include "btrtl.h"

#define VERSION "0.1"

#define RTL_EPATCH_SIGNATURE	"Realtech"
#define RTL_ROM_LMP_3499	0x3499
#define RTL_ROM_LMP_8723A	0x1200
#define RTL_ROM_LMP_8723B	0x8723
#define RTL_ROM_LMP_8821A	0x8821
#define RTL_ROM_LMP_8761A	0x8761

static int rtl_read_rom_version(struct hci_dev *hdev, u8 *version)
{
	struct rtl_rom_version_evt *rom_version;
	struct sk_buff *skb;

	/* Read RTL ROM version command */
	skb = __hci_cmd_sync(hdev, 0xfc6d, 0, NULL, HCI_INIT_TIMEOUT);
	if (IS_ERR(skb)) {
		BT_ERR("%s: Read ROM version failed (%ld)",
		       hdev->name, PTR_ERR(skb));
		return PTR_ERR(skb);
	}

	if (skb->len != sizeof(*rom_version)) {
		BT_ERR("%s: RTL version event length mismatch", hdev->name);
		kfree_skb(skb);
		return -EIO;
	}

	rom_version = (struct rtl_rom_version_evt *)skb->data;
	BT_INFO("%s: rom_version status=%x version=%x",
		hdev->name, rom_version->status, rom_version->version);

	*version = rom_version->version;

	kfree_skb(skb);
	return 0;
}

static int rtl8723b_parse_firmware(struct hci_dev *hdev, u16 lmp_subver,
				   const struct firmware *fw,
				   unsigned char **_buf)
{
	const u8 extension_sig[] = { 0x51, 0x04, 0xfd, 0x77 };
	struct rtl_epatch_header *epatch_info;
	unsigned char *buf;
	int i, ret, len;
	size_t min_size;
	u8 opcode, length, data, rom_version = 0;
	int project_id = -1;
	const unsigned char *fwptr, *chip_id_base;
	const unsigned char *patch_length_base, *patch_offset_base;
	u32 patch_offset = 0;
	u16 patch_length, num_patches;
	const u16 project_id_to_lmp_subver[] = {
		RTL_ROM_LMP_8723A,
		RTL_ROM_LMP_8723B,
		RTL_ROM_LMP_8821A,
		RTL_ROM_LMP_8761A
	};

	ret = rtl_read_rom_version(hdev, &rom_version);
	if (ret)
		return ret;

	min_size = sizeof(struct rtl_epatch_header) + sizeof(extension_sig) + 3;
	if (fw->size < min_size)
		return -EINVAL;

	fwptr = fw->data + fw->size - sizeof(extension_sig);
	if (memcmp(fwptr, extension_sig, sizeof(extension_sig)) != 0) {
		BT_ERR("%s: extension section signature mismatch", hdev->name);
		return -EINVAL;
	}

	/* Loop from the end of the firmware parsing instructions, until
	 * we find an instruction that identifies the "project ID" for the
	 * hardware supported by this firwmare file.
	 * Once we have that, we double-check that that project_id is suitable
	 * for the hardware we are working with.
	 */
	while (fwptr >= fw->data + (sizeof(struct rtl_epatch_header) + 3)) {
		opcode = *--fwptr;
		length = *--fwptr;
		data = *--fwptr;

		BT_DBG("check op=%x len=%x data=%x", opcode, length, data);

		if (opcode == 0xff) /* EOF */
			break;

		if (length == 0) {
			BT_ERR("%s: found instruction with length 0",
			       hdev->name);
			return -EINVAL;
		}

		if (opcode == 0 && length == 1) {
			project_id = data;
			break;
		}

		fwptr -= length;
	}

	if (project_id < 0) {
		BT_ERR("%s: failed to find version instruction", hdev->name);
		return -EINVAL;
	}

	if (project_id >= ARRAY_SIZE(project_id_to_lmp_subver)) {
		BT_ERR("%s: unknown project id %d", hdev->name, project_id);
		return -EINVAL;
	}

	if (lmp_subver != project_id_to_lmp_subver[project_id]) {
		BT_ERR("%s: firmware is for %x but this is a %x", hdev->name,
		       project_id_to_lmp_subver[project_id], lmp_subver);
		return -EINVAL;
	}

	epatch_info = (struct rtl_epatch_header *)fw->data;
	if (memcmp(epatch_info->signature, RTL_EPATCH_SIGNATURE, 8) != 0) {
		BT_ERR("%s: bad EPATCH signature", hdev->name);
		return -EINVAL;
	}

	num_patches = le16_to_cpu(epatch_info->num_patches);
	BT_DBG("fw_version=%x, num_patches=%d",
	       le32_to_cpu(epatch_info->fw_version), num_patches);

	/* After the rtl_epatch_header there is a funky patch metadata section.
	 * Assuming 2 patches, the layout is:
	 * ChipID1 ChipID2 PatchLength1 PatchLength2 PatchOffset1 PatchOffset2
	 *
	 * Find the right patch for this chip.
	 */
	min_size += 8 * num_patches;
	if (fw->size < min_size)
		return -EINVAL;

	chip_id_base = fw->data + sizeof(struct rtl_epatch_header);
	patch_length_base = chip_id_base + (sizeof(u16) * num_patches);
	patch_offset_base = patch_length_base + (sizeof(u16) * num_patches);
	for (i = 0; i < num_patches; i++) {
		u16 chip_id = get_unaligned_le16(chip_id_base +
						 (i * sizeof(u16)));
		if (chip_id == rom_version + 1) {
			patch_length = get_unaligned_le16(patch_length_base +
							  (i * sizeof(u16)));
			patch_offset = get_unaligned_le32(patch_offset_base +
							  (i * sizeof(u32)));
			break;
		}
	}

	if (!patch_offset) {
		BT_ERR("%s: didn't find patch for chip id %d",
		       hdev->name, rom_version);
		return -EINVAL;
	}

	BT_DBG("length=%x offset=%x index %d", patch_length, patch_offset, i);
	min_size = patch_offset + patch_length;
	if (fw->size < min_size)
		return -EINVAL;

	/* Copy the firmware into a new buffer and write the version at
	 * the end.
	 */
	len = patch_length;
	buf = kmemdup(fw->data + patch_offset, patch_length, GFP_KERNEL);
	if (!buf)
		return -ENOMEM;

	memcpy(buf + patch_length - 4, &epatch_info->fw_version, 4);

	*_buf = buf;
	return len;
}

static int rtl_download_firmware(struct hci_dev *hdev,
				 const unsigned char *data, int fw_len)
{
	struct rtl_download_cmd *dl_cmd;
	int frag_num = fw_len / RTL_FRAG_LEN + 1;
	int frag_len = RTL_FRAG_LEN;
	int ret = 0;
	int i;

	dl_cmd = kmalloc(sizeof(struct rtl_download_cmd), GFP_KERNEL);
	if (!dl_cmd)
		return -ENOMEM;

	for (i = 0; i < frag_num; i++) {
		struct sk_buff *skb;

		BT_DBG("download fw (%d/%d)", i, frag_num);

		dl_cmd->index = i;
		if (i == (frag_num - 1)) {
			dl_cmd->index |= 0x80; /* data end */
			frag_len = fw_len % RTL_FRAG_LEN;
		}
		memcpy(dl_cmd->data, data, frag_len);

		/* Send download command */
		skb = __hci_cmd_sync(hdev, 0xfc20, frag_len + 1, dl_cmd,
				     HCI_INIT_TIMEOUT);
		if (IS_ERR(skb)) {
			BT_ERR("%s: download fw command failed (%ld)",
			       hdev->name, PTR_ERR(skb));
			ret = -PTR_ERR(skb);
			goto out;
		}

		if (skb->len != sizeof(struct rtl_download_response)) {
			BT_ERR("%s: download fw event length mismatch",
			       hdev->name);
			kfree_skb(skb);
			ret = -EIO;
			goto out;
		}

		kfree_skb(skb);
		data += RTL_FRAG_LEN;
	}

out:
	kfree(dl_cmd);
	return ret;
}

static int btrtl_setup_rtl8723a(struct hci_dev *hdev)
{
	const struct firmware *fw;
	int ret;

	BT_INFO("%s: rtl: loading rtl_bt/rtl8723a_fw.bin", hdev->name);
	ret = request_firmware(&fw, "rtl_bt/rtl8723a_fw.bin", &hdev->dev);
	if (ret < 0) {
		BT_ERR("%s: Failed to load rtl_bt/rtl8723a_fw.bin", hdev->name);
		return ret;
	}

	if (fw->size < 8) {
		ret = -EINVAL;
		goto out;
	}

	/* Check that the firmware doesn't have the epatch signature
	 * (which is only for RTL8723B and newer).
	 */
	if (!memcmp(fw->data, RTL_EPATCH_SIGNATURE, 8)) {
		BT_ERR("%s: unexpected EPATCH signature!", hdev->name);
		ret = -EINVAL;
		goto out;
	}

	ret = rtl_download_firmware(hdev, fw->data, fw->size);

out:
	release_firmware(fw);
	return ret;
}

static int btrtl_setup_rtl8723b(struct hci_dev *hdev, u16 lmp_subver,
				const char *fw_name)
{
	unsigned char *fw_data = NULL;
	const struct firmware *fw;
	int ret;

	BT_INFO("%s: rtl: loading %s", hdev->name, fw_name);
	ret = request_firmware(&fw, fw_name, &hdev->dev);
	if (ret < 0) {
		BT_ERR("%s: Failed to load %s", hdev->name, fw_name);
		return ret;
	}

	ret = rtl8723b_parse_firmware(hdev, lmp_subver, fw, &fw_data);
	if (ret < 0)
		goto out;

	ret = rtl_download_firmware(hdev, fw_data, ret);
	kfree(fw_data);
	if (ret < 0)
		goto out;

out:
	release_firmware(fw);
	return ret;
}

static struct sk_buff *btrtl_read_local_version(struct hci_dev *hdev)
{
	struct sk_buff *skb;

	skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
			     HCI_INIT_TIMEOUT);
	if (IS_ERR(skb)) {
		BT_ERR("%s: HCI_OP_READ_LOCAL_VERSION failed (%ld)",
		       hdev->name, PTR_ERR(skb));
		return skb;
	}

	if (skb->len != sizeof(struct hci_rp_read_local_version)) {
		BT_ERR("%s: HCI_OP_READ_LOCAL_VERSION event length mismatch",
		       hdev->name);
		kfree_skb(skb);
		return ERR_PTR(-EIO);
	}

	return skb;
}

int btrtl_setup_realtek(struct hci_dev *hdev)
{
	struct sk_buff *skb;
	struct hci_rp_read_local_version *resp;
	u16 lmp_subver;

	skb = btrtl_read_local_version(hdev);
	if (IS_ERR(skb))
		return -PTR_ERR(skb);

	resp = (struct hci_rp_read_local_version *)skb->data;
	BT_INFO("%s: rtl: examining hci_ver=%02x hci_rev=%04x lmp_ver=%02x "
		"lmp_subver=%04x", hdev->name, resp->hci_ver, resp->hci_rev,
		resp->lmp_ver, resp->lmp_subver);

	lmp_subver = le16_to_cpu(resp->lmp_subver);
	kfree_skb(skb);

	/* Match a set of subver values that correspond to stock firmware,
	 * which is not compatible with standard btusb.
	 * If matched, upload an alternative firmware that does conform to
	 * standard btusb. Once that firmware is uploaded, the subver changes
	 * to a different value.
	 */
	switch (lmp_subver) {
	case RTL_ROM_LMP_8723A:
	case RTL_ROM_LMP_3499:
		return btrtl_setup_rtl8723a(hdev);
	case RTL_ROM_LMP_8723B:
		return btrtl_setup_rtl8723b(hdev, lmp_subver,
					    "rtl_bt/rtl8723b_fw.bin");
	case RTL_ROM_LMP_8821A:
		return btrtl_setup_rtl8723b(hdev, lmp_subver,
					    "rtl_bt/rtl8821a_fw.bin");
	case RTL_ROM_LMP_8761A:
		return btrtl_setup_rtl8723b(hdev, lmp_subver,
					    "rtl_bt/rtl8761a_fw.bin");
	default:
		BT_INFO("rtl: assuming no firmware upload needed.");
		return 0;
	}
}
EXPORT_SYMBOL_GPL(btrtl_setup_realtek);

MODULE_AUTHOR("Daniel Drake <drake@endlessm.com>");
MODULE_DESCRIPTION("Bluetooth support for Realtek devices ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");