drivers/bluetooth/btrtl.c

   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 = reject_firmware(&fw, name, &hdev->dev);
 278         if (ret < 0)
 279                 return ret;
 280         ret = fw->size;
 281         *buff = kmemdup(fw->data, ret, GFP_KERNEL);
 282         if (!*buff)
 283                 ret = -ENOMEM;
 284
 285         release_firmware(fw);
 286
 287         return ret;
 288 }
 289
 290 static int btrtl_setup_rtl8723a(struct hci_dev *hdev)
 291 {
 292         const struct firmware *fw;
 293         int ret;
 294
 295         BT_INFO("%s: rtl: loading /*(DEBLOBBED)*/", hdev->name);
 296         ret = reject_firmware(&fw, "/*(DEBLOBBED)*/", &hdev->dev);
 297         if (ret < 0) {
 298                 BT_ERR("%s: Failed to load /*(DEBLOBBED)*/", hdev->name);
 299                 return ret;
 300         }
 301
 302         if (fw->size < 8) {
 303                 ret = -EINVAL;
 304                 goto out;
 305         }
 306
 307         /* Check that the firmware doesn't have the epatch signature
 308          * (which is only for RTL8723B and newer).
 309          */
 310         if (!memcmp(fw->data, RTL_EPATCH_SIGNATURE, 8)) {
 311                 BT_ERR("%s: unexpected EPATCH signature!", hdev->name);
 312                 ret = -EINVAL;
 313                 goto out;
 314         }
 315
 316         ret = rtl_download_firmware(hdev, fw->data, fw->size);
 317
 318 out:
 319         release_firmware(fw);
 320         return ret;
 321 }
 322
 323 static int btrtl_setup_rtl8723b(struct hci_dev *hdev, u16 lmp_subver,
 324                                 const char *fw_name)
 325 {
 326         unsigned char *fw_data = NULL;
 327         const struct firmware *fw;
 328         int ret;
 329         int cfg_sz;
 330         u8 *cfg_buff = NULL;
 331         u8 *tbuff;
 332         char *cfg_name = NULL;
 333         bool config_needed = false;
 334
 335         switch (lmp_subver) {
 336         case RTL_ROM_LMP_8723B:
 337                 cfg_name = "/*(DEBLOBBED)*/";
 338                 break;
 339         case RTL_ROM_LMP_8821A:
 340                 cfg_name = "/*(DEBLOBBED)*/";
 341                 break;
 342         case RTL_ROM_LMP_8761A:
 343                 cfg_name = "/*(DEBLOBBED)*/";
 344                 break;
 345         case RTL_ROM_LMP_8822B:
 346                 cfg_name = "/*(DEBLOBBED)*/";
 347                 config_needed = true;
 348                 break;
 349         default:
 350                 BT_ERR("%s: rtl: no config according to lmp_subver %04x",
 351                        hdev->name, lmp_subver);
 352                 break;
 353         }
 354
 355         if (cfg_name) {
 356                 cfg_sz = rtl_load_config(hdev, cfg_name, &cfg_buff);
 357                 if (cfg_sz < 0) {
 358                         cfg_sz = 0;
 359                         if (config_needed)
 360                                 BT_ERR("Necessary config file %s not found\n",
 361                                        cfg_name);
 362                 }
 363         } else
 364                 cfg_sz = 0;
 365
 366         BT_INFO("%s: rtl: loading %s", hdev->name, fw_name);
 367         ret = reject_firmware(&fw, fw_name, &hdev->dev);
 368         if (ret < 0) {
 369                 BT_ERR("%s: Failed to load %s", hdev->name, fw_name);
 370                 goto err_req_fw;
 371         }
 372
 373         ret = rtl8723b_parse_firmware(hdev, lmp_subver, fw, &fw_data);
 374         if (ret < 0)
 375                 goto out;
 376
 377         if (cfg_sz) {
 378                 tbuff = kzalloc(ret + cfg_sz, GFP_KERNEL);
 379                 if (!tbuff) {
 380                         ret = -ENOMEM;
 381                         goto out;
 382                 }
 383
 384                 memcpy(tbuff, fw_data, ret);
 385                 kfree(fw_data);
 386
 387                 memcpy(tbuff + ret, cfg_buff, cfg_sz);
 388                 ret += cfg_sz;
 389
 390                 fw_data = tbuff;
 391         }
 392
 393         BT_INFO("cfg_sz %d, total size %d", cfg_sz, ret);
 394
 395         ret = rtl_download_firmware(hdev, fw_data, ret);
 396
 397 out:
 398         release_firmware(fw);
 399         kfree(fw_data);
 400 err_req_fw:
 401         if (cfg_sz)
 402                 kfree(cfg_buff);
 403         return ret;
 404 }
 405
 406 static struct sk_buff *btrtl_read_local_version(struct hci_dev *hdev)
 407 {
 408         struct sk_buff *skb;
 409
 410         skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
 411                              HCI_INIT_TIMEOUT);
 412         if (IS_ERR(skb)) {
 413                 BT_ERR("%s: HCI_OP_READ_LOCAL_VERSION failed (%ld)",
 414                        hdev->name, PTR_ERR(skb));
 415                 return skb;
 416         }
 417
 418         if (skb->len != sizeof(struct hci_rp_read_local_version)) {
 419                 BT_ERR("%s: HCI_OP_READ_LOCAL_VERSION event length mismatch",
 420                        hdev->name);
 421                 kfree_skb(skb);
 422                 return ERR_PTR(-EIO);
 423         }
 424
 425         return skb;
 426 }
 427
 428 int btrtl_setup_realtek(struct hci_dev *hdev)
 429 {
 430         struct sk_buff *skb;
 431         struct hci_rp_read_local_version *resp;
 432         u16 lmp_subver;
 433
 434         skb = btrtl_read_local_version(hdev);
 435         if (IS_ERR(skb))
 436                 return -PTR_ERR(skb);
 437
 438         resp = (struct hci_rp_read_local_version *)skb->data;
 439         BT_INFO("%s: rtl: examining hci_ver=%02x hci_rev=%04x lmp_ver=%02x "
 440                 "lmp_subver=%04x", hdev->name, resp->hci_ver, resp->hci_rev,
 441                 resp->lmp_ver, resp->lmp_subver);
 442
 443         lmp_subver = le16_to_cpu(resp->lmp_subver);
 444         kfree_skb(skb);
 445
 446         /* Match a set of subver values that correspond to stock firmware,
 447          * which is not compatible with standard btusb.
 448          * If matched, upload an alternative firmware that does conform to
 449          * standard btusb. Once that firmware is uploaded, the subver changes
 450          * to a different value.
 451          */
 452         switch (lmp_subver) {
 453         case RTL_ROM_LMP_8723A:
 454         case RTL_ROM_LMP_3499:
 455                 return btrtl_setup_rtl8723a(hdev);
 456         case RTL_ROM_LMP_8723B:
 457                 return btrtl_setup_rtl8723b(hdev, lmp_subver,
 458                                             "/*(DEBLOBBED)*/");
 459         case RTL_ROM_LMP_8821A:
 460                 return btrtl_setup_rtl8723b(hdev, lmp_subver,
 461                                             "/*(DEBLOBBED)*/");
 462         case RTL_ROM_LMP_8761A:
 463                 return btrtl_setup_rtl8723b(hdev, lmp_subver,
 464                                             "/*(DEBLOBBED)*/");
 465         case RTL_ROM_LMP_8822B:
 466                 return btrtl_setup_rtl8723b(hdev, lmp_subver,
 467                                             "/*(DEBLOBBED)*/");
 468         default:
 469                 BT_INFO("rtl: assuming no firmware upload needed.");
 470                 return 0;
 471         }
 472 }
 473 EXPORT_SYMBOL_GPL(btrtl_setup_realtek);
 474
 475 MODULE_AUTHOR("Daniel Drake <drake@endlessm.com>");
 476 MODULE_DESCRIPTION("Bluetooth support for Realtek devices ver " VERSION);
 477 MODULE_VERSION(VERSION);
 478 MODULE_LICENSE("GPL");