Set Rotation LCD Fbdev V9

engSinteck · April 3, 2024, 12:25pm

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

What LVGL version are you using? 9.1

LVGL 8.4
/Initialize and register a display driver/
static lv_disp_drv_t disp_drv;
lv_disp_drv_init(&disp_drv);
disp_drv.draw_buf = &disp_buf;
disp_drv.flush_cb = fbdev_flush;
disp_drv.hor_res = 400;
disp_drv.ver_res = 1280;
disp_drv.rotated = LV_DISP_ROT_270;
disp_drv.sw_rotate = 1;
lv_disp_drv_register(&disp_drv);

LVGL 9.1
/*Linux frame buffer device init*/
lv_display_t * disp = lv_linux_fbdev_create();
lv_linux_fbdev_set_file(disp, "/dev/fb0");
lv_display_set_resolution(disp, 400, 1280);
lv_display_set_physical_resolution(disp, 400, 1280);
lv_display_set_rotation(disp, LV_DISPLAY_ROTATION_270);


/*Linux evdev init*/
lv_indev_t * indev = lv_evdev_create(LV_INDEV_TYPE_POINTER, "/dev/input/event4");
lv_evdev_set_calibration( indev, 400, 0, 0, 1280 );

Migrating from LVGL 8.4 to LVGL 9.1, how to rotate LCD with linux framebuffer?
using the code above for 8.4 OK, but it doesn’t work in 9.1.

deonm · April 4, 2024, 9:59pm

Make sure LV_LINUX_FBDEV_RENDER_MODE is defined to support rotation,
#define LV_LINUX_FBDEV_RENDER_MODE LV_DISPLAY_RENDER_MODE_PARTIAL

github.com

lvgl/lvgl/blob/a3e9b11cda543370208f1bd5aad8a3575509010f/src/drivers/display/fb/lv_linux_fbdev.c#L273


      
              return;
          }
          
          int32_t w = lv_area_get_width(area);
          int32_t h = lv_area_get_height(area);
          lv_color_format_t cf = lv_display_get_color_format(disp);
          uint32_t px_size = lv_color_format_get_size(cf);
          
          lv_display_rotation_t rotation = lv_display_get_rotation(disp);
          
          /* Not all framebuffer kernel drivers support hardware rotation, so we need to handle it in software here */
          if(rotation != LV_DISPLAY_ROTATION_0 && LV_LINUX_FBDEV_RENDER_MODE == LV_DISPLAY_RENDER_MODE_PARTIAL) {
              /* (Re)allocate temporary buffer if needed */
              size_t buf_size = w * h * px_size;
              if(!dsc->rotated_buf || dsc->rotated_buf_size != buf_size) {
                  dsc->rotated_buf = realloc(dsc->rotated_buf, buf_size);
                  dsc->rotated_buf_size = buf_size;
              }
          
              /* Rotate the pixel buffer */
              uint32_t w_stride = lv_draw_buf_width_to_stride(w, cf);