gd/hci: add a msft module to handle Microsoft Extension (609c54c9) · Commits · e / os / android_packages_modules_Bluetooth

system/gd/hci/Android.bp

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		@@ -26,6 +26,7 @@ filegroup {
		"le_advertising_manager.cc",
		"le_scanning_manager.cc",
		"link_key.cc",
		"msft.cc",
		"uuid.cc",
		"vendor_specific_event_manager.cc",
		],

system/gd/hci/BUILD.gn

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		@@ -31,6 +31,7 @@ source_set("BluetoothHciSources") {
		"le_advertising_manager.cc",
		"le_scanning_manager.cc",
		"link_key.cc",
		"msft.cc",
		"uuid.cc",
		"vendor_specific_event_manager.cc",
		]

system/gd/hci/msft.cc

0 → 100644

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		/*
		* Copyright 2022 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/
		#include "hci/msft.h"

		#include "hal/hci_hal.h"
		#include "hci/hci_layer.h"
		#include "hci/hci_packets.h"
		#include "hci/vendor_specific_event_manager.h"

		namespace bluetooth {
		namespace hci {

		// https://learn.microsoft.com/en-us/windows-hardware/drivers/bluetooth/
		// microsoft-defined-bluetooth-hci-commands-and-events
		constexpr uint8_t kMsftEventPrefixLengthMax = 0x20;

		struct Msft {
		// MSFT opcode needs to be configured from Bluetooth driver.
		std::optional<uint16_t> opcode;
		uint64_t features{0};
		std::vector<uint8_t> prefix;
		};

		const ModuleFactory MsftExtensionManager::Factory = ModuleFactory([]() { return new MsftExtensionManager(); });

		struct MsftExtensionManager::impl {
		impl(Module* module) : module_(module){};

		~impl() {}

		void start(
		os::Handler* handler,
		hal::HciHal* hal,
		hci::HciLayer* hci_layer,
		hci::VendorSpecificEventManager* vendor_specific_event_manager) {
		LOG_INFO("MsftExtensionManager start()");
		module_handler_ = handler;
		hal_ = hal;
		hci_layer_ = hci_layer;
		vendor_specific_event_manager_ = vendor_specific_event_manager;

		/*
		* The MSFT opcode is assigned by Bluetooth controller vendors.
		* Query the kernel/drivers to derive the MSFT opcode so that
		* we can issue MSFT vendor specific commands.
		*/
		if (!supports_msft_extensions()) {
		LOG_INFO("MSFT extension is not supported.");
		return;
		}

		/*
		* The vendor prefix is required to distinguish among the vendor events
		* of different vendor specifications. Read the supported features to
		* derive the vendor prefix as well as other supported features.
		*/
		hci_layer_->EnqueueCommand(
		MsftReadSupportedFeaturesBuilder::Create(static_cast<OpCode>(msft_.opcode.value())),
		module_handler_->BindOnceOn(this, &impl::on_msft_read_supported_features_complete));
		}

		void stop() {
		LOG_INFO("MsftExtensionManager stop()");
		}

		void handle_msft_events(VendorSpecificEventView event) {
		// TODO(b/246398494): MSFT events are vendor specific events with an event prefix.

		/* Myles suggested that the structure look like
		auto payload = event.GetPayload();
		for (size_t i = 0; i < msft_.prefix.size(); i++) {
		if (msft_.prefix[i] != payload[i]) {
		// Print a warning and return
		}
		}

		MsftEventPayloadView::Create(payload.GetLittleEndianSubview(msft_.prefix.size(), payload.size()));
		// Assert that it's valid
		// Check the type of event
		// Cast it, and handle it.
		*/
		}

		bool supports_msft_extensions() {
		if (msft_.opcode.has_value()) return true;

		uint16_t opcode = hal_->getMsftOpcode();
		if (opcode == 0) return false;

		msft_.opcode = opcode;
		LOG_INFO("MSFT opcode 0x%4.4x", msft_.opcode.value());
		return true;
		}

		/*
		* Get the event prefix from the packet for configuring MSFT's
		* Vendor Specific events. Also get the MSFT supported features.
		*/
		void on_msft_read_supported_features_complete(CommandCompleteView view) {
		ASSERT(view.IsValid());
		auto status_view = MsftReadSupportedFeaturesCommandCompleteView::Create(MsftCommandCompleteView::Create(view));
		ASSERT(status_view.IsValid());

		if (status_view.GetStatus() != ErrorCode::SUCCESS) {
		LOG_WARN("MSFT Command complete status %s", ErrorCodeText(status_view.GetStatus()).c_str());
		return;
		}

		MsftSubcommandOpcode sub_opcode = status_view.GetSubcommandOpcode();
		if (sub_opcode != MsftSubcommandOpcode::MSFT_READ_SUPPORTED_FEATURES) {
		LOG_WARN("Wrong MSFT subcommand opcode %hhu returned", sub_opcode);
		return;
		}

		msft_.features = status_view.GetSupportedFeatures();

		// Save the vendor prefix to distinguish upcoming MSFT vendor events.
		auto prefix = status_view.GetPrefix();
		msft_.prefix.assign(prefix.begin(), prefix.end());

		if (prefix.size() > kMsftEventPrefixLengthMax)
		LOG_WARN("The MSFT prefix length %u is too large", (unsigned int)prefix.size());

		LOG_INFO(
		"MSFT features 0x%16.16llx prefix length %u", (unsigned long long)msft_.features, (unsigned int)prefix.size());
		}

		Module* module_;
		os::Handler* module_handler_;
		hal::HciHal* hal_;
		hci::HciLayer* hci_layer_;
		hci::VendorSpecificEventManager* vendor_specific_event_manager_;
		Msft msft_;
		};

		MsftExtensionManager::MsftExtensionManager() {
		LOG_INFO("MsftExtensionManager()");
		pimpl_ = std::make_unique<impl>(this);
		}

		void MsftExtensionManager::ListDependencies(ModuleList* list) const {
		list->add<hal::HciHal>();
		list->add<hci::HciLayer>();
		list->add<hci::VendorSpecificEventManager>();
		}

		void MsftExtensionManager::Start() {
		pimpl_->start(
		GetHandler(),
		GetDependency<hal::HciHal>(),
		GetDependency<hci::HciLayer>(),
		GetDependency<hci::VendorSpecificEventManager>());
		}

		void MsftExtensionManager::Stop() {
		pimpl_->stop();
		}

		std::string MsftExtensionManager::ToString() const {
		return "Microsoft Extension Manager";
		}

		} // namespace hci
		} // namespace bluetooth

system/gd/hci/msft.h

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		/*
		* Copyright 2022 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/
		#pragma once

		#include "hci/hci_packets.h"
		#include "module.h"

		namespace bluetooth {
		namespace hci {

		class MsftExtensionManager : public bluetooth::Module {
		public:
		MsftExtensionManager();

		MsftExtensionManager(const MsftExtensionManager&) = delete;
		MsftExtensionManager& operator=(const MsftExtensionManager&) = delete;

		static const ModuleFactory Factory;

		protected:
		void ListDependencies(ModuleList* list) const override;

		void Start() override;

		void Stop() override;

		std::string ToString() const override;

		private:
		struct impl;
		std::unique_ptr<impl> pimpl_;
		};

		} // namespace hci
		} // namespace bluetooth