Evdev compilation

nequam · February 18, 2020, 4:37pm

Description

It looks like evdev driver is not lined up with indev interface in version 6.1.1.

There are some compilation problems:

function bool evdev_read(lv_indev_data_t * data), does not have
struct _lv_indev_drv_t * indev_drv argument (ref. lv_indev_drv_t::read_cb).
evdev.h:26 #include "lvgl/lv_hal/lv_hal_indev.h" is missig \src\ subdir
there is no evdev_exit() function (to close the event file handle)

What MCU/Processor/Board and compiler are you using?

It is a compilation problem.

What do you experience?

It does not compile.
indev_drv.read_cb = evdev_read;

What do you expect?

Successful compilation

Code to reproduce

lv_indev_drv_t indev_drv;
lv_indev_drv_init(&indev_drv);
indev_drv.type 		= LV_INDEV_TYPE_POINTER;
indev_drv.read_cb 	= evdev_read;

Screenshot and/or video

If possible, add screenshots and/or videos about the current issue.

embeddedt · February 19, 2020, 12:22am

Make sure you’re using the latest lv_drivers from GitHub. That version works with the 6.x series.

github.com

littlevgl/lv_drivers/blob/1f13e4cc31f20a9afcf4309ad00927d0f2eec5e0/indev/evdev.c#L98


     evdev_key_val = 0;
     evdev_button = LV_INDEV_STATE_REL;


     return true;
}
/**
 * Get the current position and state of the evdev
 * @param data store the evdev data here
 * @return false: because the points are not buffered, so no more data to be read
 */
bool evdev_read(lv_indev_drv_t * drv, lv_indev_data_t * data)
{
    struct input_event in;


    while(read(evdev_fd, &in, sizeof(struct input_event)) > 0) {
        if(in.type == EV_REL) {
            if(in.code == REL_X)
				#if EVDEV_SWAP_AXES
					evdev_root_y += in.value;
				#else
					evdev_root_x += in.value;

nequam · February 19, 2020, 10:19am

Great, thank you.
If so, the drivers zip in the downloadable package 6.1.1 is not up to date.
There is ,even in github source, no evdev_exit (like in mouse drvier) for the event file handle release.

embeddedt · February 19, 2020, 4:32pm

Linux will close file handles automatically when the process exits, so the evdev_exit function isn’t strictly necessary.