blob: 7e88c9d19aeb605bb158ae495bbc1933d0630c15 [file] [log] [blame]
// Copyright 2020 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "typecd/udev_monitor.h"
#include <base/bind.h>
#include <base/logging.h>
#include <brillo/udev/udev_enumerate.h>
#include <re2/re2.h>
namespace {
constexpr char kPartnerAltModeRegex[] = R"(port(\d+)-partner.(\d+))";
constexpr char kPartnerRegex[] = R"(port(\d+)-partner)";
constexpr char kCableRegex[] = R"(port(\d+)-cable)";
constexpr char kPortRegex[] = R"(port(\d+))";
// TODO(pmalani): Add SOP'' support when the kernel also supports it.
constexpr char kSOPPrimePlugAltModeRegex[] = R"(port(\d+)-plug0)";
} // namespace
namespace typecd {
bool UdevMonitor::InitUdev() {
udev_ = brillo::Udev::Create();
if (!udev_) {
LOG(ERROR) << "Couldn't initialize udev object.";
return false;
}
return true;
}
bool UdevMonitor::ScanDevices() {
DCHECK(udev_);
auto enumerate = udev_->CreateEnumerate();
if (!enumerate->AddMatchSubsystem(kTypeCSubsystem)) {
PLOG(ERROR) << "Couldn't add typec to enumerator match.";
return false;
}
enumerate->ScanDevices();
auto entry = enumerate->GetListEntry();
if (!entry) {
LOG(INFO) << "No devices found.\n";
return true;
}
while (entry != nullptr) {
HandleDeviceAddedRemoved(base::FilePath(std::string(entry->GetName())),
true);
entry = entry->GetNext();
}
return true;
}
bool UdevMonitor::BeginMonitoring() {
udev_monitor_ = udev_->CreateMonitorFromNetlink(kUdevMonitorName);
if (!udev_monitor_) {
LOG(ERROR) << "Failed to create udev monitor.";
return false;
}
if (!udev_monitor_->FilterAddMatchSubsystemDeviceType(kTypeCSubsystem,
nullptr)) {
PLOG(ERROR) << "Failed to add typec subsystem to udev monitor.";
return false;
}
if (!udev_monitor_->EnableReceiving()) {
PLOG(ERROR) << "Failed to enable receiving for udev monitor.";
return false;
}
int fd = udev_monitor_->GetFileDescriptor();
if (fd == brillo::UdevMonitor::kInvalidFileDescriptor) {
PLOG(ERROR) << "Couldn't get udev monitor fd.";
return false;
}
udev_monitor_watcher_ = base::FileDescriptorWatcher::WatchReadable(
fd, base::BindRepeating(&UdevMonitor::HandleUdevEvent,
base::Unretained(this)));
if (!udev_monitor_watcher_) {
LOG(ERROR) << "Couldn't start watcher for udev monitor fd.";
return false;
}
return true;
}
void UdevMonitor::AddObserver(Observer* obs) {
observer_list_.AddObserver(obs);
}
void UdevMonitor::RemoveObserver(Observer* obs) {
observer_list_.RemoveObserver(obs);
}
bool UdevMonitor::HandleDeviceAddedRemoved(const base::FilePath& path,
bool added) {
auto name = path.BaseName();
int port_num;
for (Observer& observer : observer_list_) {
if (RE2::FullMatch(name.value(), kPortRegex, &port_num))
observer.OnPortAddedOrRemoved(path, port_num, added);
else if (RE2::FullMatch(name.value(), kPartnerRegex, &port_num))
observer.OnPartnerAddedOrRemoved(path, port_num, added);
else if (RE2::FullMatch(name.value(), kPartnerAltModeRegex, &port_num))
observer.OnPartnerAltModeAddedOrRemoved(path, port_num, added);
else if (RE2::FullMatch(name.value(), kCableRegex, &port_num))
observer.OnCableAddedOrRemoved(path, port_num, added);
else if (RE2::FullMatch(name.value(), kSOPPrimePlugAltModeRegex,
&port_num) &&
added)
observer.OnCableAltModeAdded(path, port_num);
}
return true;
}
void UdevMonitor::HandleUdevEvent() {
auto device = udev_monitor_->ReceiveDevice();
if (!device) {
LOG(ERROR) << "Udev receive device failed.";
return;
}
auto path = base::FilePath(device->GetSysPath());
if (path.empty()) {
LOG(ERROR) << "Failed to get device syspath.";
return;
}
auto action = std::string(device->GetAction());
if (action.empty()) {
LOG(ERROR) << "Failed to get device action.";
return;
}
if (action == "add")
HandleDeviceAddedRemoved(path, true);
else if (action == "remove")
HandleDeviceAddedRemoved(path, false);
}
} // namespace typecd