Hidd - Revision history

Booto: /* Private Info */

2011-09-08T16:06:16Z

Private Info

Booto: /* Private Info */

2011-09-08T13:46:17Z

Private Info

Booto: some privinfo detail

2011-09-08T13:10:13Z

some privinfo detail

Destinal at 20:46, 25 November 2010

2010-11-25T20:46:04Z

Destinal: /* Silly hidd plugin */

2010-11-25T20:44:28Z

Silly hidd plugin

Destinal: silly plugin (mostly written by bpadalino)

2010-11-25T07:22:42Z

silly plugin (mostly written by bpadalino)

Egaudet at 06:49, 18 January 2010

2010-01-18T06:49:47Z

Destinal: created new page for the beginnings of some research into the hidd human interface device daemon

2009-08-08T07:52:00Z

created new page for the beginnings of some research into the hidd human interface device daemon

New page

==Intro==

This is a research page on hidd -- how to examine what it does, how it works, etc.

==Files==
Hidd is started from upstart (/etc/event.d/hidd) with a -f option to load a given configuration file. On the emulator, this is /etc/hidd/HidPluginsVbox.xml. On a pre, this is /etc/hidd/HidPlugins.xml. There's also something called casper there, not sure what that is as of yet

==Architecture==
Hidd seems to use a modular plugin-style architecture where each plugin is a shared library.

Default files are:

libhid.so libhidavrcp.so libhidlight.so libhidqemukeypad.so libhidtouchpanel.so
libhidaccelerometer.so libhidkeypad.so libhidproximity.so libhidqemutouchpanel.so

==Plugin definition in config file==
<source lang=xml>
<plugin>
<name>HidKeypad</name>
<eventsDeferIdle>true</eventsDeferIdle>
<eventSocketAddress>/var/tmp/hidd/KeypadEventSocket</eventSocketAddress>
<cmdSocketAddress>/var/tmp/hidd/KeypadCmdSocket</cmdSocketAddress>
<path>/usr/lib/libhidkeypad.so</path>
</plugin>
</source>

==Starting the daemon==

A lot of debug information can be obtained by starting the daemon like so (on a pre, on an emulator add Vbox before .xml)

/usr/bin/hidd -vvv -f /etc/hidd/HidPlugins.xml

==Example trace==

/usr/bin/hidd -vvv -f /etc/hidd/HidPlugins-keypadonly.xml

Verbosity level set to 7

root@castle:/etc/hidd# hidd -vvvv -f /etc/hidd/HidPlugins-test.xml
Verbosity level set to 7
Plugin: 0
Name: HidKeypad
Path: /usr/lib/libhidkeypad.so
Event Socket Address: /var/tmp/hidd/KeypadEventSocket
Cmd Socket Address: /var/tmp/hidd/KeypadCmdSocket

_SetupPluginTransport:
Socket created successfully

_SetupPluginTransport:
--> Event socket address: /var/tmp/hidd/KeypadEventSocket

_SetupPluginTransport:
--> Command socket address: /var/tmp/hidd/KeypadCmdSocket

Init:
HidKeypad: init function called!

HidKeypadIpc.c:104 : GetSwitchStates: Bad file descriptor
ReportEvent:
kInputEvent received 1 events, fd: 7

_ReportStandardEvent:
Event: 0.0, type=EV_SYN, code=8, value=0

HidPluginStartReaderThread:
HidKeypad: starting reader thread

main:
Setting up power management...

ReportEvent:
kInputEvent received 2 events, fd: 7

_ReportStandardEvent:
Event: 85906.791100, type=EV_KEY, code=19, value=1

_ReportStandardEvent:
Event: 85906.791130, type=EV_SYN, code=0, value=0

ReportEvent:
kInputEvent received 2 events, fd: 7

_ReportStandardEvent:
Event: 85906.999809, type=EV_KEY, code=19, value=0

_ReportStandardEvent:
Event: 85906.999840, type=EV_SYN, code=0, value=0

@@ Line 307: / Line 307: @@
 #include <stdint.h>
-typedef int (*ReportFunction_t)(input_event *events, int num_events, int unk1, uint32_t unk2);
+typedef int (*ReportFunction_t)(input_event *events, int num_events, int is_custom_event, uint32_t unk2);
 typedef int (*ReaderFunction_t)(int event_device_fd);

@@ Line 301: / Line 301: @@
 ==Private Info==
-Some information from the privinfo internals:
+Some information from the privinfo internals that are used with the Generic function calls:
 <pre>
 #include <linux/input.h>

← Older revision		Revision as of 13:10, 8 September 2011
Line 298:		Line 298:
	You'll see its socket get registered and then some printf's when getcallback and init get called.		You'll see its socket get registered and then some printf's when getcallback and init get called.
	Next steps will be to fix to figure out gPluginPrvInfo since we probably need to put more things in it, and then to actually communicate with hidd. :)		Next steps will be to fix to figure out gPluginPrvInfo since we probably need to put more things in it, and then to actually communicate with hidd. :)
		+
		+	==Private Info==
		+
		+	Some information from the privinfo internals:
		+	<pre>
		+	#include <linux/input.h>
		+	#include <pthread.h>
		+	#include <stdint.h>
		+
		+	typedef int (ReportFunction_t)(input_event events, int num_events, int unk1, uint32_t unk2);
		+
		+	typedef int (*ReaderFunction_t)(int event_device_fd);
		+
		+	struct PrivateInfo
		+	{
		+	ReportFunc_t report_function; // +00
		+	char *event_device; // +04 can be symlink
		+	char *real_event_device; // +08 realpath(3) of event_device
		+	int *event_device_fds; // +0c file descriptors for IO (read/select/et al)
		+	char *plugin_name; // +10 name of this plugin
		+	uint32_t unk_param; // +14 passed as final unk2 to report function
		+	uint32_t unk_0; // +18 unknown
		+	uint32_t unk_1; // +1c unknown
		+	uint32_t unk_2; // +20 unknown
		+	uint32_t unk_3; // +24 unknown
		+	ReaderFunction_t reader_function; // +28 reader thread function
		+	void *event_source; // +2c pointer to an EventSource
		+	void (*init_callback)(); // +30 this is called part way through init (optional)
		+	pthread_t reader_thread; // +34 reader thread
		+	char is_running; // +38 is 1 if the reader thread is running
		+	char padding[3];
		+	pthread_mutex_t reader_mutex; // +3c mutex for reader
		+	// maybe more here?
		+	} __attribute__((packed));
		+	</pre>

← Older revision		Revision as of 20:46, 25 November 2010
Line 297:		Line 297:

	You'll see its socket get registered and then some printf's when getcallback and init get called.		You'll see its socket get registered and then some printf's when getcallback and init get called.
−	Next steps will be to ~~call init and suspend and resume from libhid's generic functions~~, and then to actually communicate with hidd. :)	+	Next steps will be to fix to figure out gPluginPrvInfo since we probably need to put more things in it, and then to actually communicate with hidd. :)

@@ Line 242: / Line 242: @@
 typedef struct PluginTable_t {
-     struct PluginTable_t *(*GetEventCallBack)() ;
+     int (*GetEventCallBack)() ;
      int (*Init)() ;
      int (*Exit)() ;
@@ Line 248: / Line 248: @@
      int (*Resume)() ;
      int (*Poll)() ;
-} PluginTable_t ;
+} PluginTable_t;
-extern PluginTable_t PluginTable ;
+extern PluginTable_t PluginTable;
-PluginTable_t *GetEventCallBack() {
+void *gPluginPrvInfo[21];
      printf( "Silly GetEventCallBack()\n" ) ;
-     return &PluginTable;
+    gPluginPrvInfo[0] = a1;
+}
-int Init() {
+int Init(a1) {
      printf( "Silly Init\n" ) ;
-     return ;
+     return HidPluginGenericInit(a1, gPluginPrvInfo);
+}
 int Exit() {
      printf( "Silly Exit\n" ) ;
-     return ;
+     return HidPluginGenericExit(gPluginPrvInfo);
+}
 int Suspend() {
      printf( "Silly Suspend\n" ) ;
-     return ;
+     return HidPluginGenericSuspend(gPluginPrvInfo);
+}
 int Resume() {
      printf( "Silly Resume\n" ) ;
-     return ;
+     return HidPluginGenericResume(gPluginPrvInfo);
+}
 int Poll() {
      printf( "Silly Poll\n" ) ;
-     return ;
+     return HidPluginGenericGetEvents(gPluginPrvInfo);
+}
@@ Line 291: / Line 294: @@
 } ;
 </pre>
 You'll see its socket get registered and then some printf's when getcallback and init get called.
 Next steps will be to call init and suspend and resume from libhid's generic functions, and then to actually communicate with hidd. :)

← Older revision		Revision as of 07:22, 25 November 2010
Line 231:		Line 231:
	rm -f $(DEMOS)		rm -f $(DEMOS)
	</pre>		</pre>
		+
		+
		+
		+
		+
		+	==Silly hidd plugin==
		+
		+	<pre>
		+	#include <stdio.h>
		+
		+	typedef struct PluginTable_t {
		+	struct PluginTable_t (GetEventCallBack)() ;
		+	int (*Init)() ;
		+	int (*Exit)() ;
		+	int (*Suspend)() ;
		+	int (*Resume)() ;
		+	int (*Poll)() ;
		+	} PluginTable_t ;
		+
		+	extern PluginTable_t PluginTable ;
		+
		+	PluginTable_t *GetEventCallBack() {
		+	printf( "Silly GetEventCallBack()\n" ) ;
		+	return &PluginTable;
		+	}
		+
		+	int Init() {
		+	printf( "Silly Init\n" ) ;
		+	return ;
		+	}
		+
		+	int Exit() {
		+	printf( "Silly Exit\n" ) ;
		+	return ;
		+	}
		+
		+	int Suspend() {
		+	printf( "Silly Suspend\n" ) ;
		+	return ;
		+	}
		+
		+	int Resume() {
		+	printf( "Silly Resume\n" ) ;
		+	return ;
		+	}
		+
		+	int Poll() {
		+	printf( "Silly Poll\n" ) ;
		+	return ;
		+	}
		+
		+	PluginTable_t PluginTable = {
		+	*GetEventCallBack,
		+	*Init,
		+	*Exit,
		+	*Suspend,
		+	*Resume,
		+	*Poll
		+	} ;
		+
		+	#ifdef UNIT_TEST
		+	int main(void) {
		+	PluginTable_t *newTable = PluginTable.GetEventCallBack() ;
		+	PluginTable.Init() ;
		+	PluginTable.Exit() ;
		+	PluginTable.Suspend() ;
		+	PluginTable.Resume() ;
		+	PluginTable.Poll() ;
		+
		+	newTable->Init() ;
		+	newTable->Exit() ;
		+	newTable->Suspend() ;
		+	newTable->Resume() ;
		+	newTable->Poll() ;
		+	}
		+	#endif
		+	</pre>
		+
		+	=== Compiling ===
		+	<pre>
		+	gcc -fPIC -shared -Wl,-soname,libhidsilly -o libhidsilly.so libhidsilly.c
		+	</pre>
		+
		+	=== Installing ===
		+
		+	Add this to hidd plugins xml file
		+
		+	<pre>
		+	<plugin>
		+	<name>HidSilly</name>
		+	<eventsDeferIdle>true</eventsDeferIdle>
		+	<eventSocketAddress>/var/tmp/hidd/SillyEventSocket</eventSocketAddress>
		+	<cmdSocketAddress>/var/tmp/hidd/SillyCmdSocket</cmdSocketAddress>
		+	<path>/usr/lib/libhidsilly.so</path>
		+	</plugin>
		+	</pre>
		+
		+	You'll see its socket get registered and then some printf's when getcallback and init get called.
		+	Next steps will be to call init and suspend and resume from libhid's generic functions, and then to actually communicate with hidd. :)

← Older revision		Revision as of 06:49, 18 January 2010
Line 88:		Line 88:
	_ReportStandardEvent:		_ReportStandardEvent:
	Event: 85906.999840, type=EV_SYN, code=0, value=0		Event: 85906.999840, type=EV_SYN, code=0, value=0
		+
		+
		+	==Listening to Hidd event==
		+	The libSDL patch provided by Palm provides good examples of listening to events via hidd. Based upon this I created a simple example program to listen to the HidKeypad events and print them to stdout. Listening directly to HidKeypad events we can observe all the keys including power button, volume keys and center gesture-area button. I built using WIDK. '''WARNING: After running this program, I cannot get the screen to come back on after sleeping via a key press. It only turns back on after reconnecting USB cable'''
		+
		+	===hidTest.c===
		+	<pre>
		+	#include <stdio.h>
		+	#include <linux/input.h>
		+	#include "HidLib.h"
		+	//#include "hid/IncsPublic/HidLib.h"
		+
		+	#define XML_FILE "/etc/hidd/HidPlugins.xml"
		+
		+	static HidPluginSettings_t* pSettings = NULL;
		+	static int numPlugins = 0;
		+
		+	int HidEventInit(void)
		+	{
		+	PmErr retVal = kPmErrorUnknown;
		+
		+	if (pSettings == NULL) {
		+	retVal = HidAllocPluginSettings(XML_FILE, &pSettings, &numPlugins);
		+
		+	if (kPmErrorNone != retVal)
		+	{
		+	pSettings = NULL;
		+	return -1;
		+	}
		+	}
		+
		+	return 0;
		+	}
		+
		+	void HidEventDeInit(void)
		+	{
		+	if (NULL != pSettings)
		+	{
		+	HidFreePluginSettings(&pSettings, numPlugins);
		+	pSettings = NULL;
		+	}
		+	}
		+
		+	void *HidEventOpen(int Device)
		+	{
		+	PmErr retVal = kPmErrorUnknown;
		+	HidHandle_t* pHandle = NULL;
		+
		+	if (pSettings == NULL) {
		+	// Ensure plugin settings are initialized.
		+	if (HidEventInit() != 0) {
		+	return NULL;
		+	}
		+	}
		+
		+	static const char* PluginName[] = {
		+	HID_KEYPAD,
		+	HID_ACCELEROMETER,
		+	HID_TOUCHPANEL
		+	};
		+
		+	retVal = HidInitPluginTransport(PluginName[Device], pSettings, numPlugins, &pHandle);
		+
		+	if (kPmErrorNone != retVal)
		+	{
		+	HidFreePluginSettings(&pSettings, numPlugins);
		+	pSettings = NULL;
		+	return NULL;
		+	}
		+
		+	return pHandle;
		+	}
		+
		+	void HidEventClose(void *Handle)
		+	{
		+	if (NULL != Handle)
		+	{
		+	HidDestroyPluginTransport((HidHandle_t**)&Handle);
		+	}
		+	}
		+
		+	int HidEventGetFd(void *Handle)
		+	{
		+	return HidHandleGetFd((HidHandle_t*)Handle);
		+	}
		+
		+	int HidEventRead(void Handle, struct input_event Events, int MaxEvents)
		+	{
		+	return HidHandleReadInputEvent((HidHandle_t)Handle, (InputEvent_t)Events, MaxEvents);
		+	}
		+
		+	int main() {
		+	void *pHandle;
		+	struct input_event myevent;
		+	int ret = 0;
		+
		+	pHandle = HidEventOpen(0);
		+
		+	while (1) {
		+	ret = HidEventRead(pHandle, &myevent, 1);
		+
		+	printf("return %d, type %d, code %d, value %d\n",
		+	ret, myevent.type, myevent.code, myevent.value);
		+
		+	// q for quit
		+	if (myevent.code == 16) {
		+	HidEventDeInit();
		+	HidEventClose(pHandle);
		+	break;
		+	}
		+	}
		+
		+	return 0;
		+	}
		+	</pre>
		+
		+	===HidLib.h===
		+	<pre>
		+	typedef int HidPluginSettings_t;
		+	typedef int HidHandle_t;
		+	typedef int PmErr;
		+	typedef struct input_event InputEvent_t;
		+
		+	#define kPmErrorNone 0
		+	#define kPmErrorUnknown -1
		+	#define HID_KEYPAD "HidKeypad"
		+	#define HID_ACCELEROMETER "HidAccelerometer"
		+	#define HID_TOUCHPANEL "HidTouchpanel"
		+	</pre>
		+
		+	===Makefile===
		+	<pre>
		+	CC = arm-none-linux-gnueabi-gcc
		+	CFLAGS = -g -O2 -I/usr/local/include
		+	LIBS = -Wl,-rpath,/usr/local/lib -L/usr/local/lib -lhid
		+	DEMOS = hidTest
		+
		+	$(DEMOS):
		+	$(CC) -o $@ $@.c $(CFLAGS) $(LIBS)
		+
		+	clean:
		+	rm -f $(DEMOS)
		+	</pre>