Linux Evdev Driver
Overview
The Linux event device (evdev) is a hardware-independent API that gives access to input events from, for example, a mouse or touchscreen. It is exposed via the Linux device file system interface.
Prerequisites
Your system has an input device configured (usually under /dev/input/ such as /dev/input/event0).
Configuring the driver
Enable the Linux LVGL evdev driver support in lv_conf.h.
#define LV_USE_EVDEV 1
Usage
To set up an event input, first create an input device with lv_edev_create setting it to the correct Linux event device.
Then link this to the LVGL display with lv_indev_set_display.
lv_indev_t *touch = lv_evdev_create(LV_INDEV_TYPE_POINTER, "/dev/input/event0");
lv_indev_set_display(touch, disp);
Ensure that an lv_display_t object is already created for disp. An example for this is shown below, using the Linux framebuffer driver.
lv_display_t * disp = lv_linux_fbdev
lv_linux_fbdev_set_file(disp, "/dev/fb0");_create();
Locating your input device
If you can't determine your input device, first run
`$cat /proc/bus/input/devices`
This should show input devices and there will be entries with the word event which give a clue as to the device to use eg. event1 would be /dev/input/event1.
You can use evtest to show data from that event source to see if it is actually the one you want.
Try:
$evtest /dev/input/event1 replacing eventX with your event device from above.
.. Autogenerated