There is no picture in lcd
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Hi and welcome to devnet,
There's not enough details:
- What version of Qt are you using ?
- What backend do you want to use for your application
- What error message did you got ?
- What hardware are you targeting ?
- What distribution is it running ?
- How are you starting your application on the device ?
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Hi,
l cross compiling qt for armv7, and then write an example to test, the code belowint main(int argc, char *argv[]) { QApplication a(argc, argv); MainWindow w; w.setStyleSheet("background-color:blue;"); w.show(); } but there is no picture in lcd, l change the code below int main(int argc, char *argv[]) { int fbFd = 0; const char *devfile = "/dev/fb0"; fbFd = open(devfile, O_RDWR); if (ioctl(fbFd, FBIOGET_VSCREENINFO, &vinfo) == -1) { perror("Error reading variable information"); exit(3); } if (fbFd == -1) { perror("Error: cannot open framebuffer device"); exit(1); } if(ioctl(fbFd, FBIOPAN_DISPLAY, &vinfo)!= 0) { return -1; } if(ioctl(fbFd, FBIOPAN_DISPLAY, &vinfo)!= 0) { return -1; } QApplication a(argc, argv); MainWindow w; w.setStyleSheet("background-color:blue;"); w.show(); if (ioctl(fbFd, FBIOGET_VSCREENINFO, &vinfo) == -1) { perror("Error reading variable information"); exit(3); } if (ioctl(fbFd, FBIOGET_FSCREENINFO, &finfo) == -1) { perror("Error reading fixed information"); exit(2); } if(ioctl(fbFd, FBIOPAN_DISPLAY, &vinfo)!= 0) { return -1; } return a.exec(); }after compile and then download, the lcd can show picture,
so, why we must add this code? whether there is wrong for my cross compiling?Edit: p3c0
Hi.
What is the platform plugin are you setting?
If it is not setting, the QT_QPA_PLATFORM environment variable parameter can be used to setting or the -platform command-line can be used with the same syntax.Like this(for example):
QT_QPA_PLATFORM=linuxfb:fb=/dev/fb0
or
./yourapp -platform linuxfb:fb=/dev/fb0 -
Dear Devopia53,
how can l set my platform plugin?
my profile is below:export TSLIB_ROOT=/usr/local/tslib
export TSLIB_TSDEVICE=/dev/event0
export TSLIB_FBDEVICE=/dev/fb0
export TSLIB_PLUGINDIR=/usr/local/tslib/lib/ts
export TSLIB_CONSOLEDEVICE=none
export TSLIB_CONFFILE=/usr/local/tslib/etc/ts.conf
export POINTERCAL_FILE=/etc/pointercal
export TSLIB_CALIBFILE=/etc/pointercal
#export QWS_SIZE=128x128
export QWS_MOUSE_PROTO=Tslib:/dev/event0
export QTDIR=/usr/local/qt
export QPEDIR=/usr/local/qt
export QWS_DISPLAY=LinuxFb:/dev/fb0
export LD_LIBRARY_PATH=$TSLIB_ROOT/lib:$QTDIR/lib:$LD_LIBRARY_PATH
export QT_QWS_FONTDIR=$QTDIR/lib/fonts
export LD_LIBRARY_PATH=/usr/local/qtlib/lib:$LD_LIBRARY_PATH
export PATH PS1 OPIEDIR QPEDIR QTDIR EDITOR TERM -
Using Qt 4?
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Did you check the permissions on the frame buffer device ?
On a side note, if locked on Qt 4, the you should go with 4.8.7 which is the latest and last version of the Qt 4 series. Otherwise, you should go with Qt 5.
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Did you check the permissions on the frame buffer device ?
On a side note, if locked on Qt 4, the you should go with 4.8.7 which is the latest and last version of the Qt 4 series. Otherwise, you should go with Qt 5.
@SGaist
here is my cross compile config:
sudo ./configure --prefix=/usr/local/qt4.8.5-arm -opensource -release -shared -Declarative -importdir /opt/imports -fast -no-largefile -qt-sql-sqlite -qt3support -exceptions -xmlpatterns -no-glib -no-phonon -no-mmx -no-3dnow -no-sse -no-sse2 -svg -no-webkit -qt-zlib -qt-libtiff -qt-libpng -qt-libjpeg -make libs -make tools -nomake examples -nomake docs -nomake demo -no-nis -no-cups -iconv -no-dbus -xplatform qws/linux-arm-g++ -embedded arm -little-endian -qt-freetype -depths 16,24,32 -qt-gfx-linuxfb -qt-gfx-transformed -qt-gfx-multiscreen -no-gfx-vnc -no-gfx-qvfb -qt-kbd-linuxinput -no-kbd-qvfb -armfpa -no-mouse-qvfb -qt-mouse-linuxtp -qt-mouse-tslib -DQT_QLOCALE_USES_FCVT -DQT_NO_QWS_CURSOR -no-pch -I/usr/local/tslib/include -L/usr/local/tslib/lib -confirm-license -
That doesn't answer my question about the permissions of
/dev/fb0on your target.On a side note, never develop nor build as root. If something goes wrong there's no restriction at what can be destroyed on your system.
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That doesn't answer my question about the permissions of
/dev/fb0on your target.On a side note, never develop nor build as root. If something goes wrong there's no restriction at what can be destroyed on your system.
@SGaist
/ # ls /dev/fb0 -l
crw-rw---- 1 root root 29, 0 Jan 1 00:00 [1;35m/dev/fb0when l use Qt/qt/qt-everywhere-opensource-src-4.8.5/examples/qws/framebuffer to test, it's ok,
your mean it's maybe to compile use "sudo"?
l will re-compile it with no "sudo". -
How are you calling your application on the command line ?
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@SGaist
l use normal user to cross compile qt5.7.0, it's still unshow anything unless l add "ioctl(fbFd, FBIOGET_FSCREENINFO, &finfo)".and it just to show one frame,
my cross compile steps is below:-
download tslib1.4.tar.gz$ ./autogen.sh
$ tar zxvf tslib1.4.tar.gz
$ ./configure CC=arm-none-linux-gnueabihf-gcc CXX=arm-none-linux-gnueabihf-g++ --prefix=/usr/local/tslib --host=arm-none-linux-gnueabihf ac_cv_func_malloc_0_nonnull=yes
$make
$sudo make install -
download qt-everywhere-opensource-src-5.7.0.tar.gz
2.1: tar zxvf qt-everywhere-opensource-src-5.7.0.tar.gz
2.2: vim qt-everywhere-opensource-src-5.7.0/qtbase/mkspecs/linux-arm-gnueabi-g++/qmake.confinclude(../common/linux.conf) + QT_QPA_DEFAULT_PLATFORM = linux #eglfs +QMAKE_CFLAGS_RELEASE += -O2 -march=armv7-a + QMAKE_CXXFLAGS_RELEASE += -O2 -march=armv7-aarm-linux-geneabi-xxx change to arm-none-linux-geneabi-xxx
2.3: vim build.sh#!/bin/sh
./configure
-v
-prefix /opt/qt5.7.0
-release
-opensource
-make libs
-xplatform linux-arm-gnueabi-g++
-optimized-qmake
-pch
-qt-sql-sqlite
-qt-libjpeg
-qt-zlib
-no-opengl
-skip qt3d
-skip qtcanvas3d
-skip qtpurchasing
-no-sse2
-no-openssl
-no-nis
-no-cups
-no-glib
-no-iconv
-nomake examples
-nomake tools
-skip qtvirtualkeyboard
-I/usr/local/tslib/include
-L/usr/local/tslib/libexit
2.4: ./build.sh
2.5: make
2.6: sudo make install -
tar /usr/local/tslib and /opt/qt5.7.0
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for arm platform
4.1: cp qt5.7.0.tar.gz and tslib.tar.gz to /opt
4.2: tar zxvf qt5.7.0.tar.gz and tar zxvf tslib.tar.gz
4.3: vim /etc/profile
#add for qt
export TSLIB_ROOT=/opt/tslib
export QT_ROOT=/opt/qt5.7.0
export TSLIB_TSDEVICE=/dev/input/event0
export TSLIB_TSEVENTTYPE=input
export TSLIB_CONFFILE=/opt/tslib/etc/ts.conf
export TSLIB_CALIBFILE=/etc/pointercal
export TSLIB_PLUGINDIR=/opt/tslib/lib/ts
export TSLIB_CONSOLEDEVICE=none
export TSLIB_FBDEVICE=/dev/fb0
export QWS_MOUSE_PROTO=tslib:/dev/input/event0
export LD_LIBRARY_PATH=/lib:/usr/lib:$QT_ROOT/lib:$TSLIB_ROOT/lib:$TSLIB_ROOT/lib/
export QT_QPA_PLATFORM_PLUGIN_PATH=$QT_ROOT/plugins
export QT_QPA_PLATFORM=linuxfb:tty=/dev/fb0
export QT_QPA_FONTDIR=$QT_ROOT/lib/fonts
export QT_QPA_GENERIC_PLUGINS=tslib
4.4: source /etc/profile
4.5: cd /opt/tslib/bin and then run ./ts_calibrate
4.6: write an test example
qmake test_qt.pro
make
adb push test_qt /home/demo
4.6: cd /home/demo and then ./test_qt
after l run ./test_qt, there is nothing in lcd,so l write test framebuffer code to test fb driver, it's show ok,
but if l add "ioctl(fbFd, FBIOPAN_DISPLAY, &vinfo)" in test_qt demo, it's show ok, but it just show one frame, unable to self-refresh,for step 4.5 and 4.6, l use another method to test, but there is still nothing in lcd.
4.5: ./ts_calibrate -qws
4.6: ./test_qt -qwsnote: there is no touch screen in my whole steps.
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What OS are you running on your target ?
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The distribution would be more useful.
Also, are you running your application as root ?
What exact message are you getting on the console when you launch the application ?
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The distribution would be more useful.
Also, are you running your application as root ?
What exact message are you getting on the console when you launch the application ?
@SGaist
yes, we run an application with root access.
we test with Qt/examples/qws/framebuffer, the message is below:root@mdm9607:/home# ./framebuffer
./framebuffer
The framebuffer device was opened successfully.Fixed screen info:
id: mdssfb_20000
smem_start: 0x8fc80000
smem_len: 155648
type: 0
type_aux: 0
visual: 2
xpanstep: 1
ypanstep: 1
ywrapstep: 0
line_length: 480
mmio_start: 0x0
mmio_len: 0
accel: 0The framebuffer device was mapped to memory successfully.
Successfully switched to graphics mode.
Variable screen info:
xres: 240
yres: 320
xres_virtual: 240
yres_virtual: 320
yoffset: 0
xoffset: 0
bits_per_pixel: 16
grayscale: 0
red: offset: 11, length: 5, msb_right: 0
green: offset: 5, length: 6, msb_right: 0
blue: offset: 0, length: 5, msb_right: 0
transp: offset: 0, length: 0, msb_right: 0
nonstd: 0
activate: 16
height: -1
width: -1
accel_flags: 0x0
pixclock: 0
left_margin: 0
right_margin: 0
upper_margin: 0
lower_margin: 0
hsync_len: 0
vsync_len: 0
sync: 0
vmode: 0Frame Buffer Performance test...
Average: 395 usecs
Bandwidth: 375.791 MByte/Sec
Max. FPS: 2531.646 fpsWill draw 3 rectangles on the screen,
they should be colored red, green and blue (in that order).
Done.
root@mdm9607:/home#l change the Qt/examples/qws/framebuffer/main.c
void drawRect_rgb16(int x0, int y0, int width, int height, int color)
{
const int bytesPerPixel = 2;
const int stride = finfo.line_length / bytesPerPixel;
const int red = (color & 0xff0000) >> (16 + 3);
const int green = (color & 0xff00) >> (8 + 2);
const int blue = (color & 0xff) >> 3;
const short color16 = blue | (green << 5) | (red << (5 + 6));short *dest = (short*)(frameBuffer) + (y0 + vinfo.yoffset) * stride + (x0 + vinfo.xoffset); int x, y; for (y = 0; y < height; ++y) { for (x = 0; x < width; ++x) { dest[x] = color16; } dest += stride; }//add by junzhang if(ioctl(fbFd, FBIOPAN_DISPLAY, &vinfo)!= 0) { return -1; }//}
there is nothing in lcd unless l add that code when l test with framebuffer example, the message is the same whether l add that code or not. -
The distribution would be more useful.
Also, are you running your application as root ?
What exact message are you getting on the console when you launch the application ?
@SGaist
l want to add
if(ioctl(fbFd, FBIOPAN_DISPLAY, &vinfo)!= 0)
{
return -1;
}/
to the code which update framebuffer in Qt,
it's mean that if something update in Qt, it will be write data to framebuffer, so, i will add that code in the function which update framebuffer.
it's that ok?
if ok, pls tell which function update framebuffer. thx. -
You likely should check the QLinuxFbScreen class.
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Do you mean by adding you ioctl code ?
