Rotating the display by 90 degrees

So after much searching, searching and searching, I have come to the conclution that the only way to get this to work in portrait mode is to flip the image that LVGL is generating.
I found this thread that has an explanation on how to do it, but since my drivers uses DMA, im not sure how to properly swap over X and Y

@embeddedt @kisvegabor can you perhaps provide an example of how to do this on the F429 driver?

static void tft_flush(lv_disp_drv_t * drv, const lv_area_t * area, lv_color_t * color_p)
{
	/*Return if the area is out the screen*/
	if(area->x2 < 0) return;
	if(area->y2 < 0) return;
	if(area->x1 > TFT_HOR_RES - 1) return;
	if(area->y1 > TFT_VER_RES - 1) return;

	/*Truncate the area to the screen*/
	int32_t act_x1 = area->x1 < 0 ? 0 : area->x1;
	int32_t act_y1 = area->y1 < 0 ? 0 : area->y1;
	int32_t act_x2 = area->x2 > TFT_HOR_RES - 1 ? TFT_HOR_RES - 1 : area->x2;
	int32_t act_y2 = area->y2 > TFT_VER_RES - 1 ? TFT_VER_RES - 1 : area->y2;

	x1_flush = act_x1;
	y1_flush = act_y1;
	x2_flush = act_x2;
	y2_fill = act_y2;
	y_fill_act = act_y1;
	buf_to_flush = color_p;


	  /*##-7- Start the DMA transfer using the interrupt mode #*/
	  /* Configure the source, destination and buffer size DMA fields and Start DMA Stream transfer */
	  /* Enable All the DMA interrupts */
	HAL_StatusTypeDef err;
	err = HAL_DMA_Start_IT(&DmaHandle,(uint32_t)buf_to_flush, (uint32_t)&my_fb[y_fill_act * TFT_HOR_RES + x1_flush],
			  (x2_flush - x1_flush + 1));
	if(err != HAL_OK)
	{
		while(1);	/*Halt on error*/
	}
}

and

static void DMA_TransferComplete(DMA_HandleTypeDef *han)
{
	y_fill_act ++;

	if(y_fill_act > y2_fill) {
		  lv_disp_flush_ready(&disp_drv);
	} else {
	  buf_to_flush += x2_flush - x1_flush + 1;
	  /*##-7- Start the DMA transfer using the interrupt mode ####################*/
	  /* Configure the source, destination and buffer size DMA fields and Start DMA Stream transfer */
	  /* Enable All the DMA interrupts */
	  if(HAL_DMA_Start_IT(han,(uint32_t)buf_to_flush, (uint32_t)&my_fb[y_fill_act * TFT_HOR_RES + x1_flush],
						  (x2_flush - x1_flush + 1)) != HAL_OK)
	  {
	    while(1);	/*Halt on error*/
	  }
	}
}