/*
* 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");
