diff options
Diffstat (limited to 'drivers/bluetooth/btrtl.c')
-rw-r--r-- | drivers/bluetooth/btrtl.c | 390 |
1 files changed, 390 insertions, 0 deletions
diff --git a/drivers/bluetooth/btrtl.c b/drivers/bluetooth/btrtl.c new file mode 100644 index 000000000..385dca5c4 --- /dev/null +++ b/drivers/bluetooth/btrtl.c @@ -0,0 +1,390 @@ +/* + * 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 /*(DEBLOBBED)*/", hdev->name); + ret = reject_firmware(&fw, "/*(DEBLOBBED)*/", &hdev->dev); + if (ret < 0) { + BT_ERR("%s: Failed to load /*(DEBLOBBED)*/", 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 = reject_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, + "/*(DEBLOBBED)*/"); + case RTL_ROM_LMP_8821A: + return btrtl_setup_rtl8723b(hdev, lmp_subver, + "/*(DEBLOBBED)*/"); + case RTL_ROM_LMP_8761A: + return btrtl_setup_rtl8723b(hdev, lmp_subver, + "/*(DEBLOBBED)*/"); + 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"); |