src/add-ons/accelerants/et6x00/GetModeInfo.c

   1 /*****************************************************************************\
   2  * Tseng Labs ET6000, ET6100 and ET6300 graphics driver for BeOS 5.
   3  * Copyright (c) 2003-2004, Evgeniy Vladimirovich Bobkov.
   4 \*****************************************************************************/
   5
   6 #include "GlobalData.h"
   7 #include "generic.h"
   8
   9
  10 /*****************************************************************************/
  11 /*
  12  * Return the current display mode.  The only time you
  13  * might return an error is if a mode hasn't been set.
  14  */
  15 status_t GET_DISPLAY_MODE(display_mode *current_mode) {
  16     /* easy for us, we return the last mode we set */
  17     *current_mode = si->dm;
  18     return B_OK;
  19 }
  20 /*****************************************************************************/
  21 /*
  22  * Return the frame buffer configuration information.
  23  */
  24 status_t GET_FRAME_BUFFER_CONFIG(frame_buffer_config *afb) {
  25     /* easy again, as the last mode set stored the info in a convienient form */
  26     *afb = si->fbc;
  27     return B_OK;
  28 }
  29 /*****************************************************************************/
  30 /*
  31  * Return the maximum and minium pixel clock limits for the specified mode.
  32  * Note that we're not making any guarantees about the ability of the
  33  * attached display to handle pixel clocks within the limits we return.
  34  * A future monitor capablilities database will post-process this
  35  * information.
  36  */
  37 status_t GET_PIXEL_CLOCK_LIMITS(display_mode *dm, uint32 *low, uint32 *high) {
  38 uint32 clockLimit;
  39 uint32 totalPix = (uint32)dm->timing.h_total * (uint32)dm->timing.v_total;
  40
  41     /* max pixel clock is pixel depth dependant */
  42     switch (dm->space & ~0x3000) {
  43         case B_RGB24: clockLimit = si->pixelClockMax24; break;
  44         case B_RGB15:
  45         case B_RGB16: clockLimit = si->pixelClockMax16; break;
  46         default:
  47             clockLimit = 0;
  48     }
  49
  50     /* lower limit of about 48Hz vertical refresh */
  51     *low = (totalPix * 48L) / 1000L;
  52     if (*low > clockLimit) return B_ERROR;
  53     *high = clockLimit;
  54
  55     return B_OK;
  56 }
  57 /*****************************************************************************/