From 145373cb1b1fcdba2059e945d0aa2613af2e84d1 Mon Sep 17 00:00:00 2001 From: Miao-chen Chou Date: Fri, 3 Apr 2020 21:44:01 +0200 Subject: [PATCH] Bluetooth: Add framework for Microsoft vendor extension Micrsoft defined a set for HCI vendor extensions. Check the following link for details: https://docs.microsoft.com/en-us/windows-hardware/drivers/bluetooth/microsoft-defined-bluetooth-hci-commands-and-events This provides the basic framework to enable the extension and read its supported features. Drivers still have to declare support for this extension before it can be utilized by the host stack. Signed-off-by: Miao-chen Chou Signed-off-by: Marcel Holtmann Signed-off-by: Johan Hedberg --- include/net/bluetooth/hci_core.h | 13 +++ net/bluetooth/Kconfig | 7 ++ net/bluetooth/Makefile | 1 + net/bluetooth/hci_core.c | 5 ++ net/bluetooth/hci_event.c | 5 ++ net/bluetooth/msft.c | 141 +++++++++++++++++++++++++++++++ net/bluetooth/msft.h | 18 ++++ 7 files changed, 190 insertions(+) create mode 100644 net/bluetooth/msft.c create mode 100644 net/bluetooth/msft.h diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h index d4e28773d378..3cb0f82d0c83 100644 --- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -484,6 +484,11 @@ struct hci_dev { struct led_trigger *power_led; #endif +#if IS_ENABLED(CONFIG_BT_MSFTEXT) + __u16 msft_opcode; + void *msft_data; +#endif + int (*open)(struct hci_dev *hdev); int (*close)(struct hci_dev *hdev); int (*flush)(struct hci_dev *hdev); @@ -1116,6 +1121,14 @@ int hci_recv_frame(struct hci_dev *hdev, struct sk_buff *skb); int hci_recv_diag(struct hci_dev *hdev, struct sk_buff *skb); __printf(2, 3) void hci_set_hw_info(struct hci_dev *hdev, const char *fmt, ...); __printf(2, 3) void hci_set_fw_info(struct hci_dev *hdev, const char *fmt, ...); + +static inline void hci_set_msft_opcode(struct hci_dev *hdev, __u16 opcode) +{ +#if IS_ENABLED(CONFIG_BT_MSFTEXT) + hdev->msft_opcode = opcode; +#endif +} + int hci_dev_open(__u16 dev); int hci_dev_close(__u16 dev); int hci_dev_do_close(struct hci_dev *hdev); diff --git a/net/bluetooth/Kconfig b/net/bluetooth/Kconfig index 77703216a2e3..9e25c6570170 100644 --- a/net/bluetooth/Kconfig +++ b/net/bluetooth/Kconfig @@ -93,6 +93,13 @@ config BT_LEDS This option selects a few LED triggers for different Bluetooth events. +config BT_MSFTEXT + bool "Enable Microsoft extensions" + depends on BT + help + This options enables support for the Microsoft defined HCI + vendor extensions. + config BT_DEBUGFS bool "Export Bluetooth internals in debugfs" depends on BT && DEBUG_FS diff --git a/net/bluetooth/Makefile b/net/bluetooth/Makefile index fda41c0b4781..41dd541a44a5 100644 --- a/net/bluetooth/Makefile +++ b/net/bluetooth/Makefile @@ -19,5 +19,6 @@ bluetooth-y := af_bluetooth.o hci_core.o hci_conn.o hci_event.o mgmt.o \ bluetooth-$(CONFIG_BT_BREDR) += sco.o bluetooth-$(CONFIG_BT_HS) += a2mp.o amp.o bluetooth-$(CONFIG_BT_LEDS) += leds.o +bluetooth-$(CONFIG_BT_MSFTEXT) += msft.o bluetooth-$(CONFIG_BT_DEBUGFS) += hci_debugfs.o bluetooth-$(CONFIG_BT_SELFTEST) += selftest.o diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index 5fb9db0b2b7b..ef0ee3a3d9ed 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -44,6 +44,7 @@ #include "hci_debugfs.h" #include "smp.h" #include "leds.h" +#include "msft.h" static void hci_rx_work(struct work_struct *work); static void hci_cmd_work(struct work_struct *work); @@ -1563,6 +1564,8 @@ setup_failed: hci_dev_test_flag(hdev, HCI_VENDOR_DIAG) && hdev->set_diag) ret = hdev->set_diag(hdev, true); + msft_do_open(hdev); + clear_bit(HCI_INIT, &hdev->flags); if (!ret) { @@ -1758,6 +1761,8 @@ int hci_dev_do_close(struct hci_dev *hdev) hci_sock_dev_event(hdev, HCI_DEV_DOWN); + msft_do_close(hdev); + if (hdev->flush) hdev->flush(hdev); diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index af396cb69602..2803beaa1c44 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -35,6 +35,7 @@ #include "a2mp.h" #include "amp.h" #include "smp.h" +#include "msft.h" #define ZERO_KEY "\x00\x00\x00\x00\x00\x00\x00\x00" \ "\x00\x00\x00\x00\x00\x00\x00\x00" @@ -6166,6 +6167,10 @@ void hci_event_packet(struct hci_dev *hdev, struct sk_buff *skb) hci_num_comp_blocks_evt(hdev, skb); break; + case HCI_EV_VENDOR: + msft_vendor_evt(hdev, skb); + break; + default: BT_DBG("%s event 0x%2.2x", hdev->name, event); break; diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c new file mode 100644 index 000000000000..d6c4e6b5ae77 --- /dev/null +++ b/net/bluetooth/msft.c @@ -0,0 +1,141 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 Google Corporation + */ + +#include +#include + +#include "msft.h" + +#define MSFT_OP_READ_SUPPORTED_FEATURES 0x00 +struct msft_cp_read_supported_features { + __u8 sub_opcode; +} __packed; +struct msft_rp_read_supported_features { + __u8 status; + __u8 sub_opcode; + __le64 features; + __u8 evt_prefix_len; + __u8 evt_prefix[0]; +} __packed; + +struct msft_data { + __u64 features; + __u8 evt_prefix_len; + __u8 *evt_prefix; +}; + +static bool read_supported_features(struct hci_dev *hdev, + struct msft_data *msft) +{ + struct msft_cp_read_supported_features cp; + struct msft_rp_read_supported_features *rp; + struct sk_buff *skb; + + cp.sub_opcode = MSFT_OP_READ_SUPPORTED_FEATURES; + + skb = __hci_cmd_sync(hdev, hdev->msft_opcode, sizeof(cp), &cp, + HCI_CMD_TIMEOUT); + if (IS_ERR(skb)) { + bt_dev_err(hdev, "Failed to read MSFT supported features (%ld)", + PTR_ERR(skb)); + return false; + } + + if (skb->len < sizeof(*rp)) { + bt_dev_err(hdev, "MSFT supported features length mismatch"); + goto failed; + } + + rp = (struct msft_rp_read_supported_features *)skb->data; + + if (rp->sub_opcode != MSFT_OP_READ_SUPPORTED_FEATURES) + goto failed; + + if (rp->evt_prefix_len > 0) { + msft->evt_prefix = kmemdup(rp->evt_prefix, rp->evt_prefix_len, + GFP_KERNEL); + if (!msft->evt_prefix) + goto failed; + } + + msft->evt_prefix_len = rp->evt_prefix_len; + msft->features = __le64_to_cpu(rp->features); + + kfree_skb(skb); + return true; + +failed: + kfree_skb(skb); + return false; +} + +void msft_do_open(struct hci_dev *hdev) +{ + struct msft_data *msft; + + if (hdev->msft_opcode == HCI_OP_NOP) + return; + + bt_dev_dbg(hdev, "Initialize MSFT extension"); + + msft = kzalloc(sizeof(*msft), GFP_KERNEL); + if (!msft) + return; + + if (!read_supported_features(hdev, msft)) { + kfree(msft); + return; + } + + hdev->msft_data = msft; +} + +void msft_do_close(struct hci_dev *hdev) +{ + struct msft_data *msft = hdev->msft_data; + + if (!msft) + return; + + bt_dev_dbg(hdev, "Cleanup of MSFT extension"); + + hdev->msft_data = NULL; + + kfree(msft->evt_prefix); + kfree(msft); +} + +void msft_vendor_evt(struct hci_dev *hdev, struct sk_buff *skb) +{ + struct msft_data *msft = hdev->msft_data; + u8 event; + + if (!msft) + return; + + /* When the extension has defined an event prefix, check that it + * matches, and otherwise just return. + */ + if (msft->evt_prefix_len > 0) { + if (skb->len < msft->evt_prefix_len) + return; + + if (memcmp(skb->data, msft->evt_prefix, msft->evt_prefix_len)) + return; + + skb_pull(skb, msft->evt_prefix_len); + } + + /* Every event starts at least with an event code and the rest of + * the data is variable and depends on the event code. + */ + if (skb->len < 1) + return; + + event = *skb->data; + skb_pull(skb, 1); + + bt_dev_dbg(hdev, "MSFT vendor event %u", event); +} diff --git a/net/bluetooth/msft.h b/net/bluetooth/msft.h new file mode 100644 index 000000000000..5aa9130e1f8a --- /dev/null +++ b/net/bluetooth/msft.h @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 Google Corporation + */ + +#if IS_ENABLED(CONFIG_BT_MSFTEXT) + +void msft_do_open(struct hci_dev *hdev); +void msft_do_close(struct hci_dev *hdev); +void msft_vendor_evt(struct hci_dev *hdev, struct sk_buff *skb); + +#else + +static inline void msft_do_open(struct hci_dev *hdev) {} +static inline void msft_do_close(struct hci_dev *hdev) {} +static inline void msft_vendor_evt(struct hci_dev *hdev, struct sk_buff *skb) {} + +#endif