Monitor for GPIO state change
Use libevdev to monitor for GPIO state change and
update item present accordingly.
Change-Id: I1959a5ea09a7570c096b05d78a190394767a5ddd
Signed-off-by: Gunnar Mills <gmills@us.ibm.com>
diff --git a/presence/gpio_presence.hpp b/presence/gpio_presence.hpp
index 47d2dc7..e8f68ca 100644
--- a/presence/gpio_presence.hpp
+++ b/presence/gpio_presence.hpp
@@ -1,5 +1,6 @@
#pragma once
#include <string>
+#include <systemd/sd-event.h>
#include <libevdev/libevdev.h>
#include "file.hpp"
@@ -10,6 +11,26 @@
namespace presence
{
+/* Need a custom deleter for freeing up sd_event */
+struct EventDeleter
+{
+ void operator()(sd_event* event) const
+ {
+ event = sd_event_unref(event);
+ }
+};
+using EventPtr = std::unique_ptr<sd_event, EventDeleter>;
+
+/* Need a custom deleter for freeing up sd_event_source */
+struct EventSourceDeleter
+{
+ void operator()(sd_event_source* eventSource) const
+ {
+ eventSource = sd_event_source_unref(eventSource);
+ }
+};
+using EventSourcePtr = std::unique_ptr<sd_event_source, EventSourceDeleter>;
+
/* Need a custom deleter for freeing up evdev struct */
struct FreeEvDev
{
@@ -55,23 +76,46 @@
to determine presence of inventory item
* @param[in] key - GPIO key to monitor
* @param[in] name - Pretty name of the inventory item
+ * @param[in] event - sd_event handler
+ * @param[in] handler - IO callback handler. Defaults to one in this
+ * class
*/
Presence(sdbusplus::bus::bus& bus,
const std::string& inventory,
const std::string& path,
const unsigned int key,
- const std::string& name) :
+ const std::string& name,
+ EventPtr& event,
+ sd_event_io_handler_t handler = Presence::processEvents) :
bus(bus),
inventory(inventory),
path(path),
key(key),
name(name),
+ event(event),
+ callbackHandler(handler),
fd(openDevice())
+
{
initEvDev();
determinePresence();
+ // Register callback handler when FD has some data
+ registerCallback();
}
+ /** @brief Callback handler when the FD has some activity on it
+ *
+ * @param[in] es - Populated event source
+ * @param[in] fd - Associated File descriptor
+ * @param[in] revents - Type of event
+ * @param[in] userData - User data that was passed during registration
+ *
+ * @return - 0 or positive number on success and negative
+ * errno otherwise
+ */
+ static int processEvents(sd_event_source* es, int fd,
+ uint32_t revents, void* userData);
+
private:
/**
* @brief Update the present property for the inventory item.
@@ -114,12 +158,27 @@
/** @brief Event structure */
EvdevPtr devicePtr;
+ /** @brief Monitor to sd_event */
+ EventPtr& event;
+
+ /** @brief Callback handler when the FD has some data */
+ sd_event_io_handler_t callbackHandler;
+
+ /** @brief event source */
+ EventSourcePtr eventSource;
+
/** @brief Opens the device and populates the descriptor */
int openDevice();
+ /** @brief attaches FD to events and sets up callback handler */
+ void registerCallback();
+
/** @brief File descriptor manager */
FileDescriptor fd;
+ /** @brief Analyzes the GPIO event and update present property*/
+ void analyzeEvent();
+
/** @brief Initializes evdev handle with the fd */
void initEvDev();
};