Posts by michele.bucceri69@gmail.com

    Hi,

    I wish to control PWM_A, PWM_B and PWM_C on an armStoneA9r2, that, according to the GPIO reference card, are associated with /sys/class/gpio# 42, 125, 126 mapped on feature pins 28, 30, 32.


    On general linux forums, I've seen it should be possible to control PWM outputs by setting values on sysfs parameters such as duty_cycle, polarity, enable.

    But I can't find any of them on the sysfs treee on the pwm subfolder.


    On my board (among the others) the most likely entries I have are:

    /sys/class/pwm/pwmchip0/device/power/

    autosuspend_delay_ms

    control

    runtime_active_time

    runtime_status

    runtime_suspended_time


    But can't set any of those values, as I catch errors. (Permission denied).

    Looking in other paths under /sys/class/pwm/pwmchip# I've not found any suitable file I can set.

    am I missing something?


    Thanks and BR,

    Michele Bucceri

    Hi,

    I'm testing an armStoneA9r2 board, and I tried to write a Qt5 demo application carefully following the tutorial you provided, but the application fails to launch, with the following message :


    QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'

    qt.qpa.egldeviceintegration: EGL device integration plugin keys: ("eglfs_emu", "eglfs_kms_egldevice", "eglfs_x11")

    qt.qpa.egldeviceintegration: EGL device integration plugin keys (sorted): ("eglfs_viv", "eglfs_x11", "eglfs_emu", "eglfs_kms_egldevice")

    qt.qpa.egldeviceintegration: Trying to load device EGL integration "eglfs_viv"

    qt.qpa.egldeviceintegration: Failed to load EGL device integration "eglfs_viv"

    qt.qpa.egldeviceintegration: Trying to load device EGL integration "eglfs_x11"

    qt.qpa.egldeviceintegration: Using EGL device integration "eglfs_x11"

    Could not open display

    Aborted



    The only way to start the application is launching through xinit:

    xinit ./testApp


    if I unset the DISPLAY environment variable, the log turns into:


    qt.qpa.egldeviceintegration: EGL device integration plugin keys: ("eglfs_emu", "eglfs_kms_egldevice", "eglfs_x11")

    qt.qpa.egldeviceintegration: EGL device integration plugin keys (sorted): ("eglfs_viv", "eglfs_emu", "eglfs_kms_egldevice", "eglfs_x11")

    qt.qpa.egldeviceintegration: Trying to load device EGL integration "eglfs_viv"

    qt.qpa.egldeviceintegration: Failed to load EGL device integration "eglfs_viv"

    qt.qpa.egldeviceintegration: Trying to load device EGL integration "eglfs_emu"

    qt.qpa.egldeviceintegration: Using EGL device integration "eglfs_emu"

    Could not open egl display

    Aborted


    The Qt config.summary log shows:

    ....

    QPA backends:

    DirectFB ............................... no

    EGLFS .................................. yes

    EGLFS details:

    EGLFS OpenWFD ........................ no

    EGLFS i.Mx6 .......................... no

    EGLFS i.Mx6 Wayland .................. no

    EGLFS RCAR ........................... no

    EGLFS EGLDevice ...................... yes

    EGLFS GBM ............................ no

    EGLFS VSP2 ........................... no

    EGLFS Mali ........................... no

    EGLFS Raspberry Pi ................... no

    EGLFS X11 ............................ yes

    LinuxFB ................................ no

    VNC .................................... yes

    Mir client ............................. no


    So from this log it appears the EGLFS is supported only through X11 and EGLDevice.

    In buildroot the Qt5/eglfs options seems activated:

    Target packages

    + --> Graphic libraries and applications (graphic/text)
    +--> Qt5

    +--> eglfs support

    +--> Default Graphical platform --> eglfs



    Digging into the buildroot config, I see that the eglfs_viv should be enabled, since the following parameters are enabeled:


    BR2_PACKAGE_FREESCALE_IMX_HAS_VIV_GPU [=y]

    BR2_PACKAGE_GPU_VIV_BIN_MX6Q [=n] (--> Ok, the CPU is a DualLite)

    BR2_PACKAGE_IMX_GPU_VIV [=y]

    BR2_PACKAGE_KERNEL_MODULE_IMX_GPU_VIV [=y]


    I assume the reason EGLFS is supported only through the X11 backend is due to the missing "EGLFS i.Mx6" option in Qt.
    Is that true? Am I missing something? Is it possible to start the application not using the X11 backend and using directly Vivante ?

    Thanks in advance!

    Michele Bucceri