changed access method for lcd sys params of ipaq h191x and mypal a716 based on Slavek Banko patch

2 files changed, 79 insertions, 29 deletions

diff --git a/libopie2/opiecore/device/odevice_ipaq.cpp b/libopie2/opiecore/device/odevice_ipaq.cpp
index e6e3145..63b60a7 100644
--- a/libopie2/opiecore/device/odevice_ipaq.cpp
+++ b/libopie2/opiecore/device/odevice_ipaq.cpp
@@ -1,129 +1,130 @@
 /*
                              This file is part of the Opie Project
              =.              (C) 2002-2005 The Opie Team <opie-devel@handhelds.org>
             .=l.
            .>+-=
  _;:,     .>    :=|.         This program is free software; you can
 .> <`_,   >  .   <=          redistribute it and/or  modify it under
 :`=1 )Y*s>-.--   :           the terms of the GNU Library General Public
 .="- .-=="i,     .._         License as published by the Free Software
  - .   .-<_>     .<>         Foundation; version 2 of the License.
      ._= =}       :
     .%`+i>       _;_.
     .i_,=:_.      -<s.       This program is distributed in the hope that
      +  .  -:.       =       it will be useful,  but WITHOUT ANY WARRANTY;
     : ..    .:,     . . .    without even the implied warranty of
     =_        +     =;=|`    MERCHANTABILITY or FITNESS FOR A
   _.=:.       :    :=>`:     PARTICULAR PURPOSE. See the GNU
 ..}^=.=       =       ;      Library General Public License for more
 ++=   -.     .`     .:       details.
  :     =  ...= . :.=-
  -.   .:....=;==+<;          You should have received a copy of the GNU
   -_. . .   )=.  =           Library General Public License along with
     --        :-=`           this library; see the file COPYING.LIB.
                              If not, write to the Free Software Foundation,
                              Inc., 59 Temple Place - Suite 330,
                              Boston, MA 02111-1307, USA.
 
 */
 
 #include "odevice_ipaq.h"
 
 /* QT */
 #include <qapplication.h>
+#include <qdir.h>
 #include <qfile.h>
 #include <qtextstream.h>
 #include <qwindowsystem_qws.h>
 
 /* OPIE */
 #include <qpe/config.h>
 #include <qpe/sound.h>
 #include <qpe/qcopenvelope_qws.h>
 
 #include <opie2/okeyfilter.h>
 #include <opie2/oresource.h>
 
 /* STD */
 #include <fcntl.h>
 #include <math.h>
 #include <stdlib.h>
 #include <signal.h>
 #include <sys/ioctl.h>
 #include <sys/time.h>
 #include <unistd.h>
 #ifndef QT_NO_SOUND
 #include <linux/soundcard.h>
 #endif
 
 
 using namespace Opie::Core;
 using namespace Opie::Core::Internal;
 
 /* KERNEL */
 #define OD_IOC(dir,type,number,size)    (( dir << 30 ) | ( type << 8 ) | ( number ) | ( size << 16 ))
 
 #define OD_IO(type,number)              OD_IOC(0,type,number,0)
 #define OD_IOW(type,number,size)        OD_IOC(1,type,number,sizeof(size))
 #define OD_IOR(type,number,size)        OD_IOC(2,type,number,sizeof(size))
 #define OD_IORW(type,number,size)       OD_IOC(3,type,number,sizeof(size))
 
 typedef struct {
   unsigned char OffOnBlink;       /* 0=off 1=on 2=Blink */
   unsigned char TotalTime;        /* Units of 5 seconds */
   unsigned char OnTime;           /* units of 100m/s */
   unsigned char OffTime;          /* units of 100m/s */
 } LED_IN;
 
 typedef struct {
         unsigned char mode;
         unsigned char pwr;
         unsigned char brightness;
 } FLITE_IN;
 
 #define LED_ON    OD_IOW( 'f', 5, LED_IN )
 #define FLITE_ON  OD_IOW( 'f', 7, FLITE_IN )
 
 struct i_button ipaq_buttons [] = {
     { Model_iPAQ_H31xx | Model_iPAQ_H36xx | Model_iPAQ_H37xx | Model_iPAQ_H38xx | Model_iPAQ_H39xx | Model_iPAQ_H5xxx | Model_iPAQ_H191x,
     Qt::Key_F9, QT_TRANSLATE_NOOP("Button", "Calendar Button"),
     "devicebuttons/ipaq_calendar",
     "datebook", "nextView()",
     "today", "raise()" },
     { Model_iPAQ_H31xx | Model_iPAQ_H36xx | Model_iPAQ_H37xx | Model_iPAQ_H38xx | Model_iPAQ_H39xx | Model_iPAQ_H5xxx | Model_iPAQ_H191x,
     Qt::Key_F10, QT_TRANSLATE_NOOP("Button", "Contacts Button"),
     "devicebuttons/ipaq_contact",
     "addressbook", "raise()",
     "addressbook", "beamBusinessCard()" },
     { Model_iPAQ_H31xx | Model_iPAQ_H36xx | Model_iPAQ_H37xx,
     Qt::Key_F11, QT_TRANSLATE_NOOP("Button", "Menu Button"),
     "devicebuttons/ipaq_menu",
     "QPE/TaskBar", "toggleMenu()",
     "QPE/TaskBar", "toggleStartMenu()" },
     { Model_iPAQ_H38xx | Model_iPAQ_H39xx | Model_iPAQ_H5xxx,
     Qt::Key_F13, QT_TRANSLATE_NOOP("Button", "Mail Button"),
     "devicebuttons/ipaq_mail",
     "opiemail", "raise()",
     "opiemail", "newMail()" },
     { Model_iPAQ_H31xx | Model_iPAQ_H36xx | Model_iPAQ_H37xx | Model_iPAQ_H38xx | Model_iPAQ_H39xx | Model_iPAQ_H5xxx | Model_iPAQ_H191x,
     Qt::Key_F12, QT_TRANSLATE_NOOP("Button", "Home Button"),
     "devicebuttons/ipaq_home",
     "QPE/Launcher", "home()",
     "buttonsettings", "raise()" },
     { Model_iPAQ_H31xx | Model_iPAQ_H36xx | Model_iPAQ_H37xx | Model_iPAQ_H38xx | Model_iPAQ_H39xx | Model_iPAQ_H5xxx,
     Qt::Key_F24, QT_TRANSLATE_NOOP("Button", "Record Button"),
     "devicebuttons/ipaq_record",
     "QPE/VMemo", "toggleRecord()",
     "sound", "raise()" },
 
     { Model_iPAQ_H191x,
     Qt::Key_F8, QT_TRANSLATE_NOOP("Button", "Mail Button"),
     "devicebuttons/ipaq_mail",
     "opiemail", "raise()",
     "opiemail", "newMail()" },
     { Model_iPAQ_H191x,
     Qt::Key_F7, QT_TRANSLATE_NOOP("Button", "Record Button"),
     "devicebuttons/ipaq_record",
     "QPE/VMemo", "toggleRecord()",
     "sound", "raise()" },
 
 };
@@ -286,196 +287,232 @@ bool iPAQ::filter ( int /*unicode*/, int keycode, int modifiers, bool isPress, b
         // H38xx/H39xx have no "Q" key anymore - this is now the Mail key
         case HardKey_Menu: {
             if (( d->m_model == Model_iPAQ_H38xx ) ||
                 ( d->m_model == Model_iPAQ_H39xx ) ||
                 ( d->m_model == Model_iPAQ_H5xxx)) {
                 newkeycode = HardKey_Mail;
             }
             break;
         }
 
         // Rotate cursor keys 180 or 270
         case Key_Left :
         case Key_Right:
         case Key_Up   :
         case Key_Down : {
             if (( d->m_model == Model_iPAQ_H31xx ) ||
                 ( d->m_model == Model_iPAQ_H38xx )) {
                 newkeycode = Key_Left + ( keycode - Key_Left + 2 ) % 4;
             }
             // Rotate the cursor keys by 270
             // keycode - Key_Left = position of the button starting from left clockwise
             // add the rotation to it and modolo. No we've the original offset
             // add the offset to the Key_Left key
             if (( d->m_model == Model_iPAQ_H5xxx ) ||
                 ( d->m_model == Model_iPAQ_H191x ) ||
                 ( d->m_model == Model_iPAQ_H1940 ))
                 newkeycode = Key_Left + ( keycode - Key_Left + 3 ) % 4;
             break;
         }
 
         // map Power Button short/long press to F6 for h191x
         case Key_F6:
             if ( d->m_model != Model_iPAQ_H191x )
                 break;
         // map Power Button short/long press to F34/F35
         case Key_SysReq: {
             if ( isPress ) {
                 if ( m_power_timer )
                     killTimer ( m_power_timer );
                 m_power_timer = startTimer ( 500 );
             }
             else if ( m_power_timer ) {
                 killTimer ( m_power_timer );
                 m_power_timer = 0;
                 QWSServer::sendKeyEvent ( -1, HardKey_Suspend, 0, true, false );
                 QWSServer::sendKeyEvent ( -1, HardKey_Suspend, 0, false, false );
             }
             newkeycode = Key_unknown;
             break;
         }
     }
 
     if ( newkeycode != keycode ) {
         if ( newkeycode != Key_unknown )
             QWSServer::sendKeyEvent ( -1, newkeycode, modifiers, isPress, autoRepeat );
         return true;
     }
     else
         return false;
 }
 
 void iPAQ::timerEvent ( QTimerEvent * )
 {
     killTimer ( m_power_timer );
     m_power_timer = 0;
     QWSServer::sendKeyEvent ( -1, HardKey_Backlight, 0, true, false );
     QWSServer::sendKeyEvent ( -1, HardKey_Backlight, 0, false, false );
 }
 
 
 void iPAQ::playAlarmSound()
 {
 #ifndef QT_NO_SOUND
     static Sound snd ( "alarm" );
     if(!snd.isFinished())
         return;
 
     changeMixerForAlarm(0, "/dev/sound/mixer", &snd );
     snd. play();
 #endif
 }
 
 bool iPAQ::setDisplayBrightness ( int bright )
 {
     bool res = false;
     int fd;
 
     if ( bright > 255 )
         bright = 255;
     if ( bright < 0 )
         bright = 0;
 
     QString cmdline;
 
     switch ( model()) {
     case Model_iPAQ_H191x:
-        if ( !bright )
-            cmdline = QString::fromLatin1( "echo 4 > /sys/class/backlight/pxafb/power");
-        else
-            cmdline = QString::fromLatin1( "echo 0 > /sys/class/backlight/pxafb/power; echo %1 > /sys/class/backlight/pxafb/brightness" ).arg( bright );
-        // No Global::shellQuote as we gurantee it to be sane
-        res = ( ::system( QFile::encodeName(cmdline) ) == 0 );
+        {
+            QDir sysClass( "/sys/class/backlight/pxafb/" );
+            sysClass.setFilter(QDir::Dirs);
+            int fd;
+            if ( sysClass.exists() ) {
+                QString sysClassPath = sysClass.absFilePath( "/sys/class/backlight/pxafb/power" );
+                fd = ::open( sysClassPath, O_WRONLY | O_NONBLOCK );
+                if ( fd ) {
+                    char buf[10];
+                    buf[0] = bright ? 0 : 4;
+                    buf[1] = '\0';
+                    res = ( ::write( fd, &buf[0], 2 ) == 0 );
+                    ::close( fd );
+                }
+                sysClassPath = sysClass.absFilePath( "/sys/class/backlight/pxafb/brightness" );
+                fd = ::open( sysClassPath, O_WRONLY | O_NONBLOCK );
+                if ( fd ) {
+                    char buf[100];
+                    int len = ::snprintf( &buf[0], sizeof buf, "%d", bright );
+                    res = ( ::write( fd, &buf[0], len ) == 0 );
+                    ::close( fd );
+                }
+            }
+        }
         break; 
         
     case Model_iPAQ_HX4700:
             cmdline = QString::fromLatin1( "echo %1 > /sys/class/backlight/w100fb/brightness" ).arg( bright );
         // No Global::shellQuote as we gurantee it to be sane
         res = ( ::system( QFile::encodeName(cmdline) ) == 0 );
         break; 
         
 
     default:
         if (( fd = ::open ( "/dev/touchscreen/0", O_WRONLY )) >= 0 ) {
             FLITE_IN bl;
             bl. mode = 1;
             bl. pwr = bright ? 1 : 0;
             bl. brightness = ( bright * ( displayBrightnessResolution() - 1 ) + 127 ) / 255;
             res = ( ::ioctl ( fd, FLITE_ON, &bl ) == 0 );
             ::close ( fd );
         }
     }
     return res;
 }
 
 int iPAQ::displayBrightnessResolution() const
 {
     switch ( model()) {
         case Model_iPAQ_H31xx:
         case Model_iPAQ_H36xx:
         case Model_iPAQ_H37xx:
             return 128;     // really 256, but >128 could damage the LCD
 
         case Model_iPAQ_H38xx:
         case Model_iPAQ_H39xx:
             return 64;
         case Model_iPAQ_H5xxx:
         case Model_iPAQ_HX4700:
             return 255;
         case Model_iPAQ_H191x:
             return 7;
         case Model_iPAQ_H1940:
             return 44;
         default:
             return 2;
     }
 }
 
 bool iPAQ::setDisplayStatus ( bool on )
 {
     bool res = false;
 
     QString cmdline;
 
     if ( model() == Model_iPAQ_H191x ) {
-        cmdline = QString::fromLatin1( "echo %1 > /sys/class/lcd/pxafb/power; echo %2 > /sys/class/backlight/pxafb/power").arg( on ? "0" : "4" ).arg( on ? "0" : "4" );
+        QDir sysClass( "/sys/class/lcd/pxafb/" );
+        sysClass.setFilter(QDir::Dirs);
+        if ( sysClass.exists() ) {
+            QString sysClassPath = sysClass.absFilePath( "/sys/class/lcd/pxafb/power" );
+            int fd = ::open( sysClassPath, O_WRONLY | O_NONBLOCK );
+            if ( fd ) {
+                char buf[10];
+                buf[0] = on ? 0 : 4;
+                buf[1] = '\0';
+                res = ( ::write( fd, &buf[0], 2 ) == 0 );
+                ::close( fd );
+            }
+        }
+        return res;
     } else {
         return OAbstractMobileDevice::setDisplayStatus(on);
     }
 
     res = ( ::system( QFile::encodeName(cmdline) ) == 0 );
 
     return res;
 }
 
 bool iPAQ::hasLightSensor() const
 {
-    return true;
+    switch (model()) {
+        case Model_iPAQ_H191x:
+            return false;
+        default:
+            return true;
+    }
 }
 
 int iPAQ::readLightSensor()
 {
     int fd;
     int val = -1;
 
     if (( fd = ::open ( "/proc/hal/light_sensor", O_RDONLY )) >= 0 ) {
         char buffer [8];
 
         if ( ::read ( fd, buffer, 5 ) == 5 ) {
             char *endptr;
 
             buffer [4] = 0;
             val = ::strtol ( buffer + 2, &endptr, 16 );
 
             if ( *endptr != 0 )
                 val = -1;
         }
         ::close ( fd );
     }
 
     return val;
 }
 
 int iPAQ::lightSensorResolution() const
 {
     return 256;
 }
diff --git a/libopie2/opiecore/device/odevice_mypal.cpp b/libopie2/opiecore/device/odevice_mypal.cpp
index 7e1245a..7eb8d1d 100644
--- a/libopie2/opiecore/device/odevice_mypal.cpp
+++ b/libopie2/opiecore/device/odevice_mypal.cpp
@@ -1,252 +1,265 @@
 /*
                              This file is part of the Opie Project
              =.              (C) 2002-2005 The Opie Team <opie-devel@handhelds.org>
             .=l.
            .>+-=
  _;:,     .>    :=|.         This program is free software; you can
 .> <`_,   >  .   <=          redistribute it and/or  modify it under
 :`=1 )Y*s>-.--   :           the terms of the GNU Library General Public
 .="- .-=="i,     .._         License as published by the Free Software
  - .   .-<_>     .<>         Foundation; version 2 of the License.
      ._= =}       :
     .%`+i>       _;_.
     .i_,=:_.      -<s.       This program is distributed in the hope that
      +  .  -:.       =       it will be useful,  but WITHOUT ANY WARRANTY;
     : ..    .:,     . . .    without even the implied warranty of
     =_        +     =;=|`    MERCHANTABILITY or FITNESS FOR A
   _.=:.       :    :=>`:     PARTICULAR PURPOSE. See the GNU
 ..}^=.=       =       ;      Library General Public License for more
 ++=   -.     .`     .:       details.
  :     =  ...= . :.=-
  -.   .:....=;==+<;          You should have received a copy of the GNU
   -_. . .   )=.  =           Library General Public License along with
     --        :-=`           this library; see the file COPYING.LIB.
                              If not, write to the Free Software Foundation,
                              Inc., 59 Temple Place - Suite 330,
                              Boston, MA 02111-1307, USA.
 
 */
 
 #include "odevice_mypal.h"
 
 /* QT */
 #include <qapplication.h>
+#include <qdir.h>
 #include <qfile.h>
 #include <qtextstream.h>
 #include <qwindowsystem_qws.h>
 
 /* OPIE */
 #include <qpe/config.h>
 #include <qpe/sound.h>
 #include <qpe/qcopenvelope_qws.h>
 
 #include <opie2/okeyfilter.h>
 #include <opie2/oresource.h>
 
 /* STD */
 #include <fcntl.h>
 #include <math.h>
 #include <stdlib.h>
 #include <signal.h>
 #include <sys/ioctl.h>
 #include <sys/time.h>
 #include <unistd.h>
 #ifndef QT_NO_SOUND
 #include <linux/soundcard.h>
 #endif
 
 
 using namespace Opie::Core;
 using namespace Opie::Core::Internal;
 
 struct m_button mypal_buttons [] = {
     { Model_MyPal_716,
     Qt::Key_F9, QT_TRANSLATE_NOOP("Button", "Calendar Button"),
     "devicebuttons/ipaq_calendar",
     "datebook", "nextView()",
     "today", "raise()" },
     { Model_MyPal_716,
     Qt::Key_F10, QT_TRANSLATE_NOOP("Button", "Contacts Button"),
     "devicebuttons/ipaq_contact",
     "addressbook", "raise()",
     "addressbook", "beamBusinessCard()" },
     { Model_MyPal_716,
     Qt::Key_F8, QT_TRANSLATE_NOOP("Button", "Mail Button"),
     "devicebuttons/ipaq_mail",
     "opiemail", "raise()",
     "opiemail", "newMail()" },
     { Model_MyPal_716,
     Qt::Key_F12, QT_TRANSLATE_NOOP("Button", "Home Button"),
     "devicebuttons/ipaq_home",
     "QPE/Launcher", "home()",
     "buttonsettings", "raise()" },
     { Model_MyPal_716,
     Qt::Key_F7, QT_TRANSLATE_NOOP("Button", "Record Button"),
     "devicebuttons/ipaq_record",
     "QPE/VMemo", "toggleRecord()",
     "sound", "raise()" },
 };
 
 void MyPal::init(const QString& model)
 {
     d->m_vendorstr = "Asus";
     d->m_vendor = Vendor_Asus;
 
     d->m_modelstr = model.mid(model.findRev('A'));
     if ( d->m_modelstr == "A716" )
         d->m_model = Model_MyPal_716;
     else
         d->m_model = Model_Unknown;
 
     d->m_rotation = Rot0;
 
     m_power_timer = 0;
 }
 
 void MyPal::initButtons()
 {
     if ( d->m_buttons )
         return;
 
     if ( isQWS( ) ) {
         addPreHandler(this);
     }
 
     d->m_buttons = new QValueList <ODeviceButton>;
 
     for ( uint i = 0; i < ( sizeof( mypal_buttons ) / sizeof( m_button )); i++ ) {
         m_button *mb = mypal_buttons + i;
         ODeviceButton b;
 
         if (( mb->model & d->m_model ) == d->m_model ) {
             b. setKeycode ( mb->code );
             b. setUserText ( QObject::tr ( "Button", mb->utext ));
             b. setPixmap ( OResource::loadPixmap ( mb->pix ));
             b. setFactoryPresetPressedAction ( OQCopMessage ( makeChannel ( mb->fpressedservice ), mb->fpressedaction ));
             b. setFactoryPresetHeldAction ( OQCopMessage ( makeChannel ( mb->fheldservice ), mb->fheldaction ));
 
             d->m_buttons->append ( b );
         }
     }
     reloadButtonMapping();
 }
 
 bool MyPal::filter ( int /*unicode*/, int keycode, int modifiers, bool isPress, bool autoRepeat )
 {
     int newkeycode = keycode;
 
     switch ( keycode ) {
         case Key_Left :
         case Key_Right:
         case Key_Up   :
         case Key_Down : {
             // Rotate the cursor keys by 270
             // keycode - Key_Left = position of the button starting from left clockwise
             // add the rotation to it and modolo. No we've the original offset
             // add the offset to the Key_Left key
             if ( d->m_model == Model_MyPal_716 )
                 newkeycode = Key_Left + ( keycode - Key_Left + 3 ) % 4;
             break;
         }
 
         // map Power Button short/long press to F6
         case Key_F6: {
             if ( isPress ) {
                 if ( m_power_timer )
                     killTimer ( m_power_timer );
                 m_power_timer = startTimer ( 500 );
             }
             else if ( m_power_timer ) {
                 killTimer ( m_power_timer );
                 m_power_timer = 0;
                 QWSServer::sendKeyEvent ( -1, HardKey_Suspend, 0, true, false );
                 QWSServer::sendKeyEvent ( -1, HardKey_Suspend, 0, false, false );
             }
             newkeycode = Key_unknown;
             break;
         }
     }
 
     if ( newkeycode != keycode ) {
         if ( newkeycode != Key_unknown )
             QWSServer::sendKeyEvent ( -1, newkeycode, modifiers, isPress, autoRepeat );
         return true;
     }
     else
         return false;
 }
 
 void MyPal::timerEvent ( QTimerEvent * )
 {
     killTimer ( m_power_timer );
     m_power_timer = 0;
     QWSServer::sendKeyEvent ( -1, HardKey_Backlight, 0, true, false );
     QWSServer::sendKeyEvent ( -1, HardKey_Backlight, 0, false, false );
 }
 
 
 void MyPal::playAlarmSound()
 {
 #ifndef QT_NO_SOUND
     static Sound snd ( "alarm" );
     if(!snd.isFinished())
         return;
 
     changeMixerForAlarm(0, "/dev/sound/mixer", &snd );
     snd. play();
 #endif
 }
 
 bool MyPal::setDisplayBrightness ( int bright )
 {
     bool res = false;
 
     if ( bright > 255 )
         bright = 255;
     if ( bright < 0 )
         bright = 0;
 
-    QString cmdline;
-
-    switch ( model()) {
-    case Model_MyPal_716:
-        if ( !bright )
-            cmdline = QString::fromLatin1( "echo 4 > /sys/class/backlight/pxafb/power");
-        else
-            cmdline = QString::fromLatin1( "echo 0 > /sys/class/backlight/pxafb/power; echo %1 > /sys/class/backlight/pxafb/brightness" ).arg( bright );
-        // No Global::shellQuote as we gurantee it to be sane
-        res = ( ::system( QFile::encodeName(cmdline) ) == 0 );
-        break; 
-    default:
-        res = OAbstractMobileDevice::setDisplayBrightness(bright);
+    QDir sysClass( "/sys/class/backlight/pxafb/" );
+    sysClass.setFilter(QDir::Dirs);
+    int fd;
+    if ( sysClass.exists() ) {
+        QString sysClassPath = sysClass.absFilePath( "/sys/class/backlight/pxafb/power" );
+        fd = ::open( sysClassPath, O_WRONLY | O_NONBLOCK );
+        if ( fd ) {
+            char buf[10];
+            buf[0] = bright ? 0 : 4;
+            buf[1] = '\0';
+            res = ( ::write( fd, &buf[0], 2 ) == 0 );
+            ::close( fd );
+        }
+        sysClassPath = sysClass.absFilePath( "/sys/class/backlight/pxafb/brightness" );
+        fd = ::open( sysClassPath, O_WRONLY | O_NONBLOCK );
+        if ( fd ) {
+            char buf[100];
+            int len = ::snprintf( &buf[0], sizeof buf, "%d", bright );
+            res = ( ::write( fd, &buf[0], len ) == 0 );
+            ::close( fd );
+        }
     }
 
     return res;
 }
 
 int MyPal::displayBrightnessResolution() const
 {
     switch ( model()) {
         case Model_MyPal_716:
             return 7;
         default:
             return OAbstractMobileDevice::displayBrightnessResolution();
     }
 }
 
 bool MyPal::setDisplayStatus ( bool on )
 {
     bool res = false;
 
-    QString cmdline;
-
-    if ( model() == Model_MyPal_716 ) {
-        cmdline = QString::fromLatin1( "echo %1 > /sys/class/lcd/pxafb/power; echo %2 > /sys/class/backlight/pxafb/power").arg( on ? "0" : "4" ).arg( on ? "0" : "4" );
-    } else {
-        return OAbstractMobileDevice::setDisplayStatus(on);
+    QDir sysClass( "/sys/class/lcd/" );
+    sysClass.setFilter(QDir::Dirs);
+    if ( sysClass.exists() ) {
+        QString sysClassPath = sysClass.absFilePath( "/sys/class/lcd/pxafb/power" );
+        int fd = ::open( sysClassPath, O_WRONLY | O_NONBLOCK );
+        if ( fd ) {
+            char buf[10];
+            buf[0] = on ? 0 : 4;
+            buf[1] = '\0';
+            res = ( ::write( fd, &buf[0], 2 ) == 0 );
+            ::close( fd );
+        }
     }
 
-    res = ( ::system( QFile::encodeName(cmdline) ) == 0 );
-
     return res;
 }