mutter/src/backends/x11/meta-monitor-manager-xrandr.c

/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */

/*
 * Copyright (C) 2001, 2002 Havoc Pennington
 * Copyright (C) 2002, 2003 Red Hat Inc.
 * Some ICCCM manager selection code derived from fvwm2,
 * Copyright (C) 2001 Dominik Vogt, Matthias Clasen, and fvwm2 team
 * Copyright (C) 2003 Rob Adams
 * Copyright (C) 2004-2006 Elijah Newren
 * Copyright (C) 2013 Red Hat Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#include "config.h"

#include "meta-monitor-manager-xrandr.h"

#include <string.h>
#include <stdlib.h>
#include <math.h>
#include <clutter/clutter.h>

#include <X11/Xatom.h>
#include <X11/extensions/Xrandr.h>
#include <X11/extensions/dpms.h>
#include <X11/Xlib-xcb.h>
#include <xcb/randr.h>

#include "meta-backend-x11.h"
#include <meta/main.h>
#include <meta/errors.h>
#include "edid.h"
#include "meta-monitor-config.h"

#define ALL_TRANSFORMS ((1 << (META_MONITOR_TRANSFORM_FLIPPED_270 + 1)) - 1)

/* Look for DPI_FALLBACK in:
 * http://git.gnome.org/browse/gnome-settings-daemon/tree/plugins/xsettings/gsd-xsettings-manager.c
 * for the reasoning */
#define DPI_FALLBACK 96.0

struct _MetaMonitorManagerXrandr
{
  MetaMonitorManager parent_instance;

  Display *xdisplay;
  XRRScreenResources *resources;
  int rr_event_base;
  int rr_error_base;
};

struct _MetaMonitorManagerXrandrClass
{
  MetaMonitorManagerClass parent_class;
};

G_DEFINE_TYPE (MetaMonitorManagerXrandr, meta_monitor_manager_xrandr, META_TYPE_MONITOR_MANAGER);

static MetaMonitorTransform
meta_monitor_transform_from_xrandr (Rotation rotation)
{
  static const MetaMonitorTransform y_reflected_map[4] = {
    META_MONITOR_TRANSFORM_FLIPPED_180,
    META_MONITOR_TRANSFORM_FLIPPED_90,
    META_MONITOR_TRANSFORM_FLIPPED,
    META_MONITOR_TRANSFORM_FLIPPED_270
  };
  MetaMonitorTransform ret;

  switch (rotation & 0x7F)
    {
    default:
    case RR_Rotate_0:
      ret = META_MONITOR_TRANSFORM_NORMAL;
      break;
    case RR_Rotate_90:
      ret = META_MONITOR_TRANSFORM_90;
      break;
    case RR_Rotate_180:
      ret = META_MONITOR_TRANSFORM_180;
      break;
    case RR_Rotate_270:
      ret = META_MONITOR_TRANSFORM_270;
      break;
    }

  if (rotation & RR_Reflect_X)
    return ret + 4;
  else if (rotation & RR_Reflect_Y)
    return y_reflected_map[ret];
  else
    return ret;
}

#define ALL_ROTATIONS (RR_Rotate_0 | RR_Rotate_90 | RR_Rotate_180 | RR_Rotate_270)

static MetaMonitorTransform
meta_monitor_transform_from_xrandr_all (Rotation rotation)
{
  unsigned ret;

  /* Handle the common cases first (none or all) */
  if (rotation == 0 || rotation == RR_Rotate_0)
    return (1 << META_MONITOR_TRANSFORM_NORMAL);

  /* All rotations and one reflection -> all of them by composition */
  if ((rotation & ALL_ROTATIONS) &&
      ((rotation & RR_Reflect_X) || (rotation & RR_Reflect_Y)))
    return ALL_TRANSFORMS;

  ret = 1 << META_MONITOR_TRANSFORM_NORMAL;
  if (rotation & RR_Rotate_90)
    ret |= 1 << META_MONITOR_TRANSFORM_90;
  if (rotation & RR_Rotate_180)
    ret |= 1 << META_MONITOR_TRANSFORM_180;
  if (rotation & RR_Rotate_270)
    ret |= 1 << META_MONITOR_TRANSFORM_270;
  if (rotation & (RR_Rotate_0 | RR_Reflect_X))
    ret |= 1 << META_MONITOR_TRANSFORM_FLIPPED;
  if (rotation & (RR_Rotate_90 | RR_Reflect_X))
    ret |= 1 << META_MONITOR_TRANSFORM_FLIPPED_90;
  if (rotation & (RR_Rotate_180 | RR_Reflect_X))
    ret |= 1 << META_MONITOR_TRANSFORM_FLIPPED_180;
  if (rotation & (RR_Rotate_270 | RR_Reflect_X))
    ret |= 1 << META_MONITOR_TRANSFORM_FLIPPED_270;

  return ret;
}

static gboolean
output_get_integer_property (MetaMonitorManagerXrandr *manager_xrandr,
                             MetaOutput *output, const char *propname,
                             gint *value)
{
  gboolean exists = FALSE;
  Atom atom, actual_type;
  int actual_format;
  unsigned long nitems, bytes_after;
  unsigned char *buffer;

  atom = XInternAtom (manager_xrandr->xdisplay, propname, False);
  XRRGetOutputProperty (manager_xrandr->xdisplay,
                        (XID)output->winsys_id,
                        atom,
                        0, G_MAXLONG, False, False, XA_INTEGER,
                        &actual_type, &actual_format,
                        &nitems, &bytes_after, &buffer);

  exists = (actual_type == XA_INTEGER && actual_format == 32 && nitems == 1);

  if (exists && value != NULL)
    *value = ((int*)buffer)[0];

  XFree (buffer);
  return exists;
}

static gboolean
output_get_property_exists (MetaMonitorManagerXrandr *manager_xrandr,
                            MetaOutput *output, const char *propname)
{
  gboolean exists = FALSE;
  Atom atom, actual_type;
  int actual_format;
  unsigned long nitems, bytes_after;
  unsigned char *buffer;

  atom = XInternAtom (manager_xrandr->xdisplay, propname, False);
  XRRGetOutputProperty (manager_xrandr->xdisplay,
                        (XID)output->winsys_id,
                        atom,
                        0, G_MAXLONG, False, False, AnyPropertyType,
                        &actual_type, &actual_format,
                        &nitems, &bytes_after, &buffer);

  exists = (actual_type != None);

  XFree (buffer);
  return exists;
}

static gboolean
output_get_boolean_property (MetaMonitorManagerXrandr *manager_xrandr,
                             MetaOutput *output, const char *propname)
{
  gboolean value = FALSE;
  Atom atom, actual_type;
  int actual_format;
  unsigned long nitems, bytes_after;
  unsigned char *buffer;

  atom = XInternAtom (manager_xrandr->xdisplay, propname, False);
  XRRGetOutputProperty (manager_xrandr->xdisplay,
                        (XID)output->winsys_id,
                        atom,
                        0, G_MAXLONG, False, False, XA_CARDINAL,
                        &actual_type, &actual_format,
                        &nitems, &bytes_after, &buffer);

  if (actual_type != XA_CARDINAL || actual_format != 32 || nitems < 1)
    goto out;

  value = ((int*)buffer)[0];

 out:
  XFree (buffer);
  return value;
}

static gboolean
output_get_presentation_xrandr (MetaMonitorManagerXrandr *manager_xrandr,
                                MetaOutput *output)
{
  return output_get_boolean_property (manager_xrandr, output, "_MUTTER_PRESENTATION_OUTPUT");
}

static int
normalize_backlight (MetaOutput *output,
                     int         hw_value)
{
  return round ((double)(hw_value - output->backlight_min) /
                (output->backlight_max - output->backlight_min) * 100.0);
}

static int
output_get_backlight_xrandr (MetaMonitorManagerXrandr *manager_xrandr,
                             MetaOutput               *output)
{
  int value = -1;
  Atom atom, actual_type;
  int actual_format;
  unsigned long nitems, bytes_after;
  unsigned char *buffer;

  atom = XInternAtom (manager_xrandr->xdisplay, "Backlight", False);
  XRRGetOutputProperty (manager_xrandr->xdisplay,
                        (XID)output->winsys_id,
                        atom,
                        0, G_MAXLONG, False, False, XA_INTEGER,
                        &actual_type, &actual_format,
                        &nitems, &bytes_after, &buffer);

  if (actual_type != XA_INTEGER || actual_format != 32 || nitems < 1)
    goto out;

  value = ((int*)buffer)[0];

 out:
  XFree (buffer);
  if (value > 0)
    return normalize_backlight (output, value);
  else
    return -1;
}

static void
output_get_backlight_limits_xrandr (MetaMonitorManagerXrandr *manager_xrandr,
                                    MetaOutput               *output)
{
  Atom atom;
  xcb_connection_t *xcb_conn;
  xcb_randr_query_output_property_reply_t *reply;

  atom = XInternAtom (manager_xrandr->xdisplay, "Backlight", False);

  xcb_conn = XGetXCBConnection (manager_xrandr->xdisplay);
  reply = xcb_randr_query_output_property_reply (xcb_conn,
                                                 xcb_randr_query_output_property (xcb_conn,
                                                                                  (xcb_randr_output_t) output->winsys_id,
                                                                                  (xcb_atom_t) atom),
                                                 NULL);

  /* This can happen on systems without backlights. */
  if (reply == NULL)
    return;

  if (!reply->range || reply->length != 2)
    {
      meta_verbose ("backlight %s was not range\n", output->name);
      goto out;
    }

  int32_t *values = xcb_randr_query_output_property_valid_values (reply);
  output->backlight_min = values[0];
  output->backlight_max = values[1];

out:
  free (reply);
}

static int
compare_outputs (const void *one,
                 const void *two)
{
  const MetaOutput *o_one = one, *o_two = two;

  return strcmp (o_one->name, o_two->name);
}

static guint8 *
get_edid_property (Display  *dpy,
                   RROutput  output,
                   Atom      atom,
                   gsize    *len)
{
  unsigned char *prop;
  int actual_format;
  unsigned long nitems, bytes_after;
  Atom actual_type;
  guint8 *result;

  XRRGetOutputProperty (dpy, output, atom,
                        0, 100, False, False,
                        AnyPropertyType,
                        &actual_type, &actual_format,
                        &nitems, &bytes_after, &prop);

  if (actual_type == XA_INTEGER && actual_format == 8)
    {
      result = g_memdup (prop, nitems);
      if (len)
        *len = nitems;
    }
  else
    {
      result = NULL;
    }

  XFree (prop);

  return result;
}

static GBytes *
read_output_edid (MetaMonitorManagerXrandr *manager_xrandr,
                  XID                       winsys_id)
{
  Atom edid_atom;
  guint8 *result;
  gsize len;

  edid_atom = XInternAtom (manager_xrandr->xdisplay, "EDID", FALSE);
  result = get_edid_property (manager_xrandr->xdisplay, winsys_id, edid_atom, &len);

  if (!result)
    {
      edid_atom = XInternAtom (manager_xrandr->xdisplay, "EDID_DATA", FALSE);
      result = get_edid_property (manager_xrandr->xdisplay, winsys_id, edid_atom, &len);
    }

  if (!result)
    {
      edid_atom = XInternAtom (manager_xrandr->xdisplay, "XFree86_DDC_EDID1_RAWDATA", FALSE);
      result = get_edid_property (manager_xrandr->xdisplay, winsys_id, edid_atom, &len);
    }

  if (result)
    {
      if (len > 0 && len % 128 == 0)
        return g_bytes_new_take (result, len);
      else
        g_free (result);
    }

  return NULL;
}

static gboolean
output_get_hotplug_mode_update (MetaMonitorManagerXrandr *manager_xrandr,
                                MetaOutput               *output)
{
  return output_get_property_exists (manager_xrandr, output, "hotplug_mode_update");
}

static gint
output_get_suggested_x (MetaMonitorManagerXrandr *manager_xrandr,
                        MetaOutput               *output)
{
  gint val;
  if (output_get_integer_property (manager_xrandr, output, "suggested X", &val))
    return val;

  return -1;
}

static gint
output_get_suggested_y (MetaMonitorManagerXrandr *manager_xrandr,
                        MetaOutput               *output)
{
  gint val;
  if (output_get_integer_property (manager_xrandr, output, "suggested Y", &val))
    return val;

  return -1;
}

static char *
get_xmode_name (XRRModeInfo *xmode)
{
  int width = xmode->width;
  int height = xmode->height;

  if (xmode->hSkew != 0)
    {
      width += 2 * (xmode->hSkew >> 8);
      height += 2 * (xmode->hSkew & 0xff);
    }

  return g_strdup_printf ("%dx%d", width, height);
}

static void
meta_monitor_manager_xrandr_read_current (MetaMonitorManager *manager)
{
  MetaMonitorManagerXrandr *manager_xrandr = META_MONITOR_MANAGER_XRANDR (manager);
  XRRScreenResources *resources;
  RROutput primary_output;
  unsigned int i, j, k;
  unsigned int n_actual_outputs;
  int min_width, min_height;
  Screen *screen;
  BOOL dpms_capable, dpms_enabled;
  CARD16 dpms_state;

  if (manager_xrandr->resources)
    XRRFreeScreenResources (manager_xrandr->resources);
  manager_xrandr->resources = NULL;

  dpms_capable = DPMSCapable (manager_xrandr->xdisplay);

  if (dpms_capable &&
      DPMSInfo (manager_xrandr->xdisplay, &dpms_state, &dpms_enabled) &&
      dpms_enabled)
    {
      switch (dpms_state)
        {
        case DPMSModeOn:
          manager->power_save_mode = META_POWER_SAVE_ON;
          break;
        case DPMSModeStandby:
          manager->power_save_mode = META_POWER_SAVE_STANDBY;
          break;
        case DPMSModeSuspend:
          manager->power_save_mode = META_POWER_SAVE_SUSPEND;
          break;
        case DPMSModeOff:
          manager->power_save_mode = META_POWER_SAVE_OFF;
          break;
        default:
          manager->power_save_mode = META_POWER_SAVE_UNSUPPORTED;
          break;
        }
    }
  else
    {
      manager->power_save_mode = META_POWER_SAVE_UNSUPPORTED;
    }

  XRRGetScreenSizeRange (manager_xrandr->xdisplay, DefaultRootWindow (manager_xrandr->xdisplay),
			 &min_width,
			 &min_height,
			 &manager->max_screen_width,
			 &manager->max_screen_height);

  screen = ScreenOfDisplay (manager_xrandr->xdisplay,
			    DefaultScreen (manager_xrandr->xdisplay));
  /* This is updated because we called RRUpdateConfiguration below */
  manager->screen_width = WidthOfScreen (screen);
  manager->screen_height = HeightOfScreen (screen);

  resources = XRRGetScreenResourcesCurrent (manager_xrandr->xdisplay,
					    DefaultRootWindow (manager_xrandr->xdisplay));
  if (!resources)
    return;

  manager_xrandr->resources = resources;
  manager->n_outputs = resources->noutput;
  manager->n_crtcs = resources->ncrtc;
  manager->n_modes = resources->nmode;
  manager->outputs = g_new0 (MetaOutput, manager->n_outputs);
  manager->modes = g_new0 (MetaMonitorMode, manager->n_modes);
  manager->crtcs = g_new0 (MetaCRTC, manager->n_crtcs);

  for (i = 0; i < (unsigned)resources->nmode; i++)
    {
      XRRModeInfo *xmode = &resources->modes[i];
      MetaMonitorMode *mode;

      mode = &manager->modes[i];

      mode->mode_id = xmode->id;
      mode->width = xmode->width;
      mode->height = xmode->height;
      mode->refresh_rate = (xmode->dotClock /
			    ((float)xmode->hTotal * xmode->vTotal));
      mode->name = get_xmode_name (xmode);
    }

  for (i = 0; i < (unsigned)resources->ncrtc; i++)
    {
      XRRCrtcInfo *crtc;
      MetaCRTC *meta_crtc;

      crtc = XRRGetCrtcInfo (manager_xrandr->xdisplay, resources, resources->crtcs[i]);

      meta_crtc = &manager->crtcs[i];

      meta_crtc->crtc_id = resources->crtcs[i];
      meta_crtc->rect.x = crtc->x;
      meta_crtc->rect.y = crtc->y;
      meta_crtc->rect.width = crtc->width;
      meta_crtc->rect.height = crtc->height;
      meta_crtc->is_dirty = FALSE;
      meta_crtc->transform = meta_monitor_transform_from_xrandr (crtc->rotation);
      meta_crtc->all_transforms = meta_monitor_transform_from_xrandr_all (crtc->rotations);

      for (j = 0; j < (unsigned)resources->nmode; j++)
	{
	  if (resources->modes[j].id == crtc->mode)
	    {
	      meta_crtc->current_mode = &manager->modes[j];
	      break;
	    }
	}

      XRRFreeCrtcInfo (crtc);
    }

  primary_output = XRRGetOutputPrimary (manager_xrandr->xdisplay,
					DefaultRootWindow (manager_xrandr->xdisplay));

  n_actual_outputs = 0;
  for (i = 0; i < (unsigned)resources->noutput; i++)
    {
      XRROutputInfo *output;
      MetaOutput *meta_output;

      output = XRRGetOutputInfo (manager_xrandr->xdisplay, resources, resources->outputs[i]);

      meta_output = &manager->outputs[n_actual_outputs];

      if (output->connection != RR_Disconnected)
	{
          GBytes *edid;
          MonitorInfo *parsed_edid;

	  meta_output->winsys_id = resources->outputs[i];
	  meta_output->name = g_strdup (output->name);

          edid = read_output_edid (manager_xrandr, meta_output->winsys_id);
          if (edid)
            {
              gsize len;

              parsed_edid = decode_edid (g_bytes_get_data (edid, &len));
              if (parsed_edid)
                {
                  meta_output->vendor = g_strndup (parsed_edid->manufacturer_code, 4);
                  if (parsed_edid->dsc_product_name[0])
                    meta_output->product = g_strndup (parsed_edid->dsc_product_name, 14);
                  else
                    meta_output->product = g_strdup_printf ("0x%04x", (unsigned)parsed_edid->product_code);
                  if (parsed_edid->dsc_serial_number[0])
                    meta_output->serial = g_strndup (parsed_edid->dsc_serial_number, 14);
                  else
                    meta_output->serial = g_strdup_printf ("0x%08x", parsed_edid->serial_number);

                  g_free (parsed_edid);
                }

              g_bytes_unref (edid);
            }

          if (!meta_output->vendor)
            {
              meta_output->vendor = g_strdup ("unknown");
              meta_output->product = g_strdup ("unknown");
              meta_output->serial = g_strdup ("unknown");
            }
	  meta_output->width_mm = output->mm_width;
	  meta_output->height_mm = output->mm_height;
	  meta_output->subpixel_order = COGL_SUBPIXEL_ORDER_UNKNOWN;
          meta_output->hotplug_mode_update = output_get_hotplug_mode_update (manager_xrandr, meta_output);
	  meta_output->suggested_x = output_get_suggested_x (manager_xrandr, meta_output);
	  meta_output->suggested_y = output_get_suggested_y (manager_xrandr, meta_output);

	  meta_output->n_modes = output->nmode;
	  meta_output->modes = g_new0 (MetaMonitorMode *, meta_output->n_modes);
	  for (j = 0; j < meta_output->n_modes; j++)
	    {
	      for (k = 0; k < manager->n_modes; k++)
		{
		  if (output->modes[j] == (XID)manager->modes[k].mode_id)
		    {
		      meta_output->modes[j] = &manager->modes[k];
		      break;
		    }
		}
	    }
	  meta_output->preferred_mode = meta_output->modes[0];

	  meta_output->n_possible_crtcs = output->ncrtc;
	  meta_output->possible_crtcs = g_new0 (MetaCRTC *, meta_output->n_possible_crtcs);
	  for (j = 0; j < (unsigned)output->ncrtc; j++)
	    {
	      for (k = 0; k < manager->n_crtcs; k++)
		{
		  if ((XID)manager->crtcs[k].crtc_id == output->crtcs[j])
		    {
		      meta_output->possible_crtcs[j] = &manager->crtcs[k];
		      break;
		    }
		}
	    }

	  meta_output->crtc = NULL;
	  for (j = 0; j < manager->n_crtcs; j++)
	    {
	      if ((XID)manager->crtcs[j].crtc_id == output->crtc)
		{
		  meta_output->crtc = &manager->crtcs[j];
		  break;
		}
	    }

	  meta_output->n_possible_clones = output->nclone;
	  meta_output->possible_clones = g_new0 (MetaOutput *, meta_output->n_possible_clones);
	  /* We can build the list of clones now, because we don't have the list of outputs
	     yet, so temporarily set the pointers to the bare XIDs, and then we'll fix them
	     in a second pass
	  */
	  for (j = 0; j < (unsigned)output->nclone; j++)
	    {
	      meta_output->possible_clones[j] = GINT_TO_POINTER (output->clones[j]);
	    }

	  meta_output->is_primary = ((XID)meta_output->winsys_id == primary_output);
	  meta_output->is_presentation = output_get_presentation_xrandr (manager_xrandr, meta_output);
	  output_get_backlight_limits_xrandr (manager_xrandr, meta_output);

	  if (!(meta_output->backlight_min == 0 && meta_output->backlight_max == 0))
	    meta_output->backlight = output_get_backlight_xrandr (manager_xrandr, meta_output);
	  else
	    meta_output->backlight = -1;

	  n_actual_outputs++;
	}

      XRRFreeOutputInfo (output);
    }

  manager->n_outputs = n_actual_outputs;

  /* Sort the outputs for easier handling in MetaMonitorConfig */
  qsort (manager->outputs, manager->n_outputs, sizeof (MetaOutput), compare_outputs);

  /* Now fix the clones */
  for (i = 0; i < manager->n_outputs; i++)
    {
      MetaOutput *meta_output;

      meta_output = &manager->outputs[i];

      for (j = 0; j < meta_output->n_possible_clones; j++)
	{
	  RROutput clone = GPOINTER_TO_INT (meta_output->possible_clones[j]);

	  for (k = 0; k < manager->n_outputs; k++)
	    {
	      if (clone == (XID)manager->outputs[k].winsys_id)
		{
		  meta_output->possible_clones[j] = &manager->outputs[k];
		  break;
		}
	    }
	}
    }
}

static GBytes *
meta_monitor_manager_xrandr_read_edid (MetaMonitorManager *manager,
                                       MetaOutput         *output)
{
  MetaMonitorManagerXrandr *manager_xrandr = META_MONITOR_MANAGER_XRANDR (manager);

  return read_output_edid (manager_xrandr, output->winsys_id);
}

static void
meta_monitor_manager_xrandr_set_power_save_mode (MetaMonitorManager *manager,
						 MetaPowerSave       mode)
{
  MetaMonitorManagerXrandr *manager_xrandr = META_MONITOR_MANAGER_XRANDR (manager);
  CARD16 state;

  switch (mode) {
  case META_POWER_SAVE_ON:
    state = DPMSModeOn;
    break;
  case META_POWER_SAVE_STANDBY:
    state = DPMSModeStandby;
    break;
  case META_POWER_SAVE_SUSPEND:
    state = DPMSModeSuspend;
    break;
  case META_POWER_SAVE_OFF:
    state = DPMSModeOff;
    break;
  default:
    return;
  }

  DPMSForceLevel (manager_xrandr->xdisplay, state);
  DPMSSetTimeouts (manager_xrandr->xdisplay, 0, 0, 0);
}

static Rotation
meta_monitor_transform_to_xrandr (MetaMonitorTransform transform)
{
  switch (transform)
    {
    case META_MONITOR_TRANSFORM_NORMAL:
      return RR_Rotate_0;
    case META_MONITOR_TRANSFORM_90:
      return RR_Rotate_90;
    case META_MONITOR_TRANSFORM_180:
      return RR_Rotate_180;
    case META_MONITOR_TRANSFORM_270:
      return RR_Rotate_270;
    case META_MONITOR_TRANSFORM_FLIPPED:
      return RR_Reflect_X | RR_Rotate_0;
    case META_MONITOR_TRANSFORM_FLIPPED_90:
      return RR_Reflect_X | RR_Rotate_90;
    case META_MONITOR_TRANSFORM_FLIPPED_180:
      return RR_Reflect_X | RR_Rotate_180;
    case META_MONITOR_TRANSFORM_FLIPPED_270:
      return RR_Reflect_X | RR_Rotate_270;
    }

  g_assert_not_reached ();
}

static void
output_set_presentation_xrandr (MetaMonitorManagerXrandr *manager_xrandr,
                                MetaOutput               *output,
                                gboolean                  presentation)
{
  Atom atom;
  int value = presentation;

  atom = XInternAtom (manager_xrandr->xdisplay, "_MUTTER_PRESENTATION_OUTPUT", False);
  XRRChangeOutputProperty (manager_xrandr->xdisplay,
                           (XID)output->winsys_id,
                           atom,
                           XA_CARDINAL, 32, PropModeReplace,
                           (unsigned char*) &value, 1);
}

static void
meta_monitor_manager_xrandr_apply_configuration (MetaMonitorManager *manager,
						 MetaCRTCInfo       **crtcs,
						 unsigned int         n_crtcs,
						 MetaOutputInfo     **outputs,
						 unsigned int         n_outputs)
{
  MetaMonitorManagerXrandr *manager_xrandr = META_MONITOR_MANAGER_XRANDR (manager);
  unsigned i;
  int width, height, width_mm, height_mm;

  XGrabServer (manager_xrandr->xdisplay);

  /* First compute the new size of the screen (framebuffer) */
  width = 0; height = 0;
  for (i = 0; i < n_crtcs; i++)
    {
      MetaCRTCInfo *crtc_info = crtcs[i];
      MetaCRTC *crtc = crtc_info->crtc;
      crtc->is_dirty = TRUE;

      if (crtc_info->mode == NULL)
        continue;

      if (meta_monitor_transform_is_rotated (crtc_info->transform))
        {
          width = MAX (width, crtc_info->x + crtc_info->mode->height);
          height = MAX (height, crtc_info->y + crtc_info->mode->width);
        }
      else
        {
          width = MAX (width, crtc_info->x + crtc_info->mode->width);
          height = MAX (height, crtc_info->y + crtc_info->mode->height);
        }
    }

  /* Second disable all newly disabled CRTCs, or CRTCs that in the previous
     configuration would be outside the new framebuffer (otherwise X complains
     loudly when resizing)
     CRTC will be enabled again after resizing the FB
  */
  for (i = 0; i < n_crtcs; i++)
    {
      MetaCRTCInfo *crtc_info = crtcs[i];
      MetaCRTC *crtc = crtc_info->crtc;

      if (crtc_info->mode == NULL ||
          crtc->rect.x + crtc->rect.width > width ||
          crtc->rect.y + crtc->rect.height > height)
        {
          XRRSetCrtcConfig (manager_xrandr->xdisplay,
                            manager_xrandr->resources,
                            (XID)crtc->crtc_id,
                            CurrentTime,
                            0, 0,
                            None,
                            RR_Rotate_0,
                            NULL, 0);

          crtc->rect.x = 0;
          crtc->rect.y = 0;
          crtc->rect.width = 0;
          crtc->rect.height = 0;
          crtc->current_mode = NULL;
        }
    }

  /* Disable CRTCs not mentioned in the list */
  for (i = 0; i < manager->n_crtcs; i++)
    {
      MetaCRTC *crtc = &manager->crtcs[i];

      if (crtc->is_dirty)
        {
          crtc->is_dirty = FALSE;
          continue;
        }
      if (crtc->current_mode == NULL)
        continue;

      XRRSetCrtcConfig (manager_xrandr->xdisplay,
                        manager_xrandr->resources,
                        (XID)crtc->crtc_id,
                        CurrentTime,
                        0, 0,
                        None,
                        RR_Rotate_0,
                        NULL, 0);

      crtc->rect.x = 0;
      crtc->rect.y = 0;
      crtc->rect.width = 0;
      crtc->rect.height = 0;
      crtc->current_mode = NULL;
    }

  g_assert (width > 0 && height > 0);
  /* The 'physical size' of an X screen is meaningless if that screen
   * can consist of many monitors. So just pick a size that make the
   * dpi 96.
   *
   * Firefox and Evince apparently believe what X tells them.
   */
  width_mm = (width / DPI_FALLBACK) * 25.4 + 0.5;
  height_mm = (height / DPI_FALLBACK) * 25.4 + 0.5;
  XRRSetScreenSize (manager_xrandr->xdisplay, DefaultRootWindow (manager_xrandr->xdisplay),
                    width, height, width_mm, height_mm);

  for (i = 0; i < n_crtcs; i++)
    {
      MetaCRTCInfo *crtc_info = crtcs[i];
      MetaCRTC *crtc = crtc_info->crtc;

      if (crtc_info->mode != NULL)
        {
          MetaMonitorMode *mode;
          XID *outputs;
          unsigned int j, n_outputs;
          int width, height;
          Status ok;

          mode = crtc_info->mode;

          n_outputs = crtc_info->outputs->len;
          outputs = g_new (XID, n_outputs);

          for (j = 0; j < n_outputs; j++)
            {
              MetaOutput *output;

              output = ((MetaOutput**)crtc_info->outputs->pdata)[j];

              output->is_dirty = TRUE;
              output->crtc = crtc;

              outputs[j] = output->winsys_id;
            }

          ok = XRRSetCrtcConfig (manager_xrandr->xdisplay,
                                 manager_xrandr->resources,
                                 (XID)crtc->crtc_id,
                                 CurrentTime,
                                 crtc_info->x, crtc_info->y,
                                 (XID)mode->mode_id,
                                 meta_monitor_transform_to_xrandr (crtc_info->transform),
                                 outputs, n_outputs);

          if (ok != Success)
            {
              meta_warning ("Configuring CRTC %d with mode %d (%d x %d @ %f) at position %d, %d and transfrom %u failed\n",
                            (unsigned)(crtc->crtc_id), (unsigned)(mode->mode_id),
                            mode->width, mode->height, (float)mode->refresh_rate,
                            crtc_info->x, crtc_info->y, crtc_info->transform);
              goto next;
            }

          if (meta_monitor_transform_is_rotated (crtc_info->transform))
            {
              width = mode->height;
              height = mode->width;
            }
          else
            {
              width = mode->width;
              height = mode->height;
            }

          crtc->rect.x = crtc_info->x;
          crtc->rect.y = crtc_info->y;
          crtc->rect.width = width;
          crtc->rect.height = height;
          crtc->current_mode = mode;
          crtc->transform = crtc_info->transform;

        next:
          g_free (outputs);
        }
    }

  for (i = 0; i < n_outputs; i++)
    {
      MetaOutputInfo *output_info = outputs[i];
      MetaOutput *output = output_info->output;

      if (output_info->is_primary)
        {
          XRRSetOutputPrimary (manager_xrandr->xdisplay,
                               DefaultRootWindow (manager_xrandr->xdisplay),
                               (XID)output_info->output->winsys_id);
        }

      output_set_presentation_xrandr (manager_xrandr,
                                      output_info->output,
                                      output_info->is_presentation);

      output->is_primary = output_info->is_primary;
      output->is_presentation = output_info->is_presentation;
    }

  /* Disable outputs not mentioned in the list */
  for (i = 0; i < manager->n_outputs; i++)
    {
      MetaOutput *output = &manager->outputs[i];

      if (output->is_dirty)
        {
          output->is_dirty = FALSE;
          continue;
        }

      output->crtc = NULL;
      output->is_primary = FALSE;
    }

  XUngrabServer (manager_xrandr->xdisplay);
  XFlush (manager_xrandr->xdisplay);
}

static void
meta_monitor_manager_xrandr_change_backlight (MetaMonitorManager *manager,
					      MetaOutput         *output,
					      gint                value)
{
  MetaMonitorManagerXrandr *manager_xrandr = META_MONITOR_MANAGER_XRANDR (manager);
  Atom atom;
  int hw_value;

  hw_value = round ((double)value / 100.0 * output->backlight_max + output->backlight_min);

  atom = XInternAtom (manager_xrandr->xdisplay, "Backlight", False);
  XRRChangeOutputProperty (manager_xrandr->xdisplay,
                           (XID)output->winsys_id,
                           atom,
                           XA_INTEGER, 32, PropModeReplace,
                           (unsigned char *) &hw_value, 1);

  /* We're not selecting for property notifies, so update the value immediately */
  output->backlight = normalize_backlight (output, hw_value);
}

static void
meta_monitor_manager_xrandr_get_crtc_gamma (MetaMonitorManager  *manager,
					    MetaCRTC            *crtc,
					    gsize               *size,
					    unsigned short     **red,
					    unsigned short     **green,
					    unsigned short     **blue)
{
  MetaMonitorManagerXrandr *manager_xrandr = META_MONITOR_MANAGER_XRANDR (manager);
  XRRCrtcGamma *gamma;

  gamma = XRRGetCrtcGamma (manager_xrandr->xdisplay, (XID)crtc->crtc_id);

  *size = gamma->size;
  *red = g_memdup (gamma->red, sizeof (unsigned short) * gamma->size);
  *green = g_memdup (gamma->green, sizeof (unsigned short) * gamma->size);
  *blue = g_memdup (gamma->blue, sizeof (unsigned short) * gamma->size);

  XRRFreeGamma (gamma);
}

static void
meta_monitor_manager_xrandr_set_crtc_gamma (MetaMonitorManager *manager,
					    MetaCRTC           *crtc,
					    gsize               size,
					    unsigned short     *red,
					    unsigned short     *green,
					    unsigned short     *blue)
{
  MetaMonitorManagerXrandr *manager_xrandr = META_MONITOR_MANAGER_XRANDR (manager);
  XRRCrtcGamma *gamma;

  gamma = XRRAllocGamma (size);
  memcpy (gamma->red, red, sizeof (unsigned short) * size);
  memcpy (gamma->green, green, sizeof (unsigned short) * size);
  memcpy (gamma->blue, blue, sizeof (unsigned short) * size);

  XRRSetCrtcGamma (manager_xrandr->xdisplay, (XID)crtc->crtc_id, gamma);

  XRRFreeGamma (gamma);
}

static void
meta_monitor_manager_xrandr_init (MetaMonitorManagerXrandr *manager_xrandr)
{
  MetaBackendX11 *backend = META_BACKEND_X11 (meta_get_backend ());

  manager_xrandr->xdisplay = meta_backend_x11_get_xdisplay (backend);

  if (!XRRQueryExtension (manager_xrandr->xdisplay,
			  &manager_xrandr->rr_event_base,
			  &manager_xrandr->rr_error_base))
    {
      return;
    }
  else
    {
      /* We only use ScreenChangeNotify, but GDK uses the others,
	 and we don't want to step on its toes */
      XRRSelectInput (manager_xrandr->xdisplay,
		      DefaultRootWindow (manager_xrandr->xdisplay),
		      RRScreenChangeNotifyMask
		      | RRCrtcChangeNotifyMask
		      | RROutputPropertyNotifyMask);
    }
}

static void
meta_monitor_manager_xrandr_finalize (GObject *object)
{
  MetaMonitorManagerXrandr *manager_xrandr = META_MONITOR_MANAGER_XRANDR (object);

  if (manager_xrandr->resources)
    XRRFreeScreenResources (manager_xrandr->resources);
  manager_xrandr->resources = NULL;

  G_OBJECT_CLASS (meta_monitor_manager_xrandr_parent_class)->finalize (object);
}

static void
meta_monitor_manager_xrandr_class_init (MetaMonitorManagerXrandrClass *klass)
{
  MetaMonitorManagerClass *manager_class = META_MONITOR_MANAGER_CLASS (klass);
  GObjectClass *object_class = G_OBJECT_CLASS (klass);

  object_class->finalize = meta_monitor_manager_xrandr_finalize;

  manager_class->read_current = meta_monitor_manager_xrandr_read_current;
  manager_class->read_edid = meta_monitor_manager_xrandr_read_edid;
  manager_class->apply_configuration = meta_monitor_manager_xrandr_apply_configuration;
  manager_class->set_power_save_mode = meta_monitor_manager_xrandr_set_power_save_mode;
  manager_class->change_backlight = meta_monitor_manager_xrandr_change_backlight;
  manager_class->get_crtc_gamma = meta_monitor_manager_xrandr_get_crtc_gamma;
  manager_class->set_crtc_gamma = meta_monitor_manager_xrandr_set_crtc_gamma;
}

gboolean
meta_monitor_manager_xrandr_handle_xevent (MetaMonitorManagerXrandr *manager_xrandr,
					   XEvent                   *event)
{
  MetaMonitorManager *manager = META_MONITOR_MANAGER (manager_xrandr);
  gboolean hotplug;

  if ((event->type - manager_xrandr->rr_event_base) != RRScreenChangeNotify)
    return FALSE;

  XRRUpdateConfiguration (event);

  meta_monitor_manager_read_current_config (manager);

  hotplug = manager_xrandr->resources->timestamp < manager_xrandr->resources->configTimestamp;
  if (hotplug)
    {
      /* This is a hotplug event, so go ahead and build a new configuration. */
      meta_monitor_manager_on_hotplug (manager);
    }
  else
    {
      /* Something else changed -- tell the world about it. */
      meta_monitor_manager_rebuild_derived (manager);
    }

  return TRUE;
}