presence: Add gpio presence sensor
Add a gpio presence implementation of the PresenceSensor
interface.
The gpio sensor simply maps the on off state of a gpio
directly to the xyz.openbmc_project.Inventory.Item
Present property.
Change-Id: I071dd475bebb15372edb59506352746c20542eff
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/presence/gpio.cpp b/presence/gpio.cpp
new file mode 100644
index 0000000..dfd72db
--- /dev/null
+++ b/presence/gpio.cpp
@@ -0,0 +1,98 @@
+/**
+ * Copyright © 2017 IBM Corporation
+ *
+ * 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 <memory>
+#include <phosphor-logging/elog-errors.hpp>
+#include <phosphor-logging/elog.hpp>
+#include <tuple>
+#include <xyz/openbmc_project/Common/Callout/error.hpp>
+#include "gpio.hpp"
+#include "rpolicy.hpp"
+#include "sdevent.hpp"
+
+namespace phosphor
+{
+namespace fan
+{
+namespace presence
+{
+
+Gpio::Gpio(
+ const std::string& physDevice,
+ unsigned int physPin) :
+ currentState(false),
+ evdevfd(open("/dev/input/by-path/platform-gpio-keys-event",
+ O_RDONLY | O_NONBLOCK)),
+ evdev(evdevpp::evdev::newFromFD(evdevfd())),
+ phys(physDevice),
+ pin(physPin),
+ callback(nullptr)
+{
+
+}
+
+bool Gpio::start()
+{
+ callback = std::make_unique<sdevent::event::io::IO>(
+ util::SDEvent::getEvent(),
+ evdevfd(),
+ [this](auto& s){this->ioCallback(s);});
+ currentState = present();
+ return currentState;
+}
+
+void Gpio::stop()
+{
+ callback = nullptr;
+}
+
+bool Gpio::present()
+{
+ return evdev.fetch(EV_KEY, pin) != 0;
+}
+
+void Gpio::fail()
+{
+ using namespace sdbusplus::xyz::openbmc_project::Common::Callout::Error;
+ using namespace phosphor::logging;
+ using namespace xyz::openbmc_project::Common::Callout;
+
+ report<sdbusplus::xyz::openbmc_project::Common::Callout::Error::GPIO>(
+ GPIO::CALLOUT_GPIO_NUM(pin),
+ GPIO::CALLOUT_ERRNO(0),
+ GPIO::CALLOUT_DEVICE_PATH(phys.c_str()));
+}
+
+void Gpio::ioCallback(sdevent::source::Source& source)
+{
+ unsigned int type, code, value;
+
+ std::tie(type, code, value) = evdev.next();
+ if (type != EV_KEY || code != pin)
+ {
+ return;
+ }
+
+ bool newState = value != 0;
+
+ if (currentState != newState)
+ {
+ getPolicy().stateChanged(newState);
+ currentState = newState;
+ }
+}
+} // namespace presence
+} // namespace fan
+} // namespace phosphor