dpms: Consolidate a bunch of stuff into Xext/dpms.c

Most of this is a legacy of the old "extmod" design where you could load
_some_ extensions dynamically but only if the server had been built with
support for them in the first place.

Note that since we now only initialize the DPMS extension if at least
one screen supports it, we no longer need DPMSCapableFlag: if it would
be false, we would never read its value.

Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Eric Anholt <eric@anholt.net>

Xext/dpms.c

@@ -43,6 +43,13 @@ Equipment Corporation.
 #include "scrnintstr.h"
 #include "windowstr.h"
 
+CARD16 DPMSPowerLevel = 0;
+Bool DPMSDisabledSwitch = FALSE;
+CARD32 DPMSStandbyTime;
+CARD32 DPMSSuspendTime;
+CARD32 DPMSOffTime;
+Bool DPMSEnabled;
+
 Bool
 DPMSSupported(void)
 {
@@ -136,7 +143,7 @@ ProcDPMSCapable(ClientPtr client)
         .type = X_Reply,
         .sequenceNumber = client->sequence,
         .length = 0,
-        .capable = DPMSCapableFlag
+        .capable = TRUE
     };
 
     REQUEST_SIZE_MATCH(xDPMSCapableReq);
@@ -204,11 +211,9 @@ ProcDPMSEnable(ClientPtr client)
 
     REQUEST_SIZE_MATCH(xDPMSEnableReq);
 
-    if (DPMSCapableFlag) {
-        DPMSEnabled = TRUE;
-        if (!was_enabled)
-            SetScreenSaverTimer();
-    }
+    DPMSEnabled = TRUE;
+    if (!was_enabled)
+        SetScreenSaverTimer();
 
     return Success;
 }
@@ -427,7 +432,12 @@ DPMSCloseDownExtension(ExtensionEntry *e)
 void
 DPMSExtensionInit(void)
 {
-    AddExtension(DPMSExtensionName, 0, 0,
-                 ProcDPMSDispatch, SProcDPMSDispatch,
-                 DPMSCloseDownExtension, StandardMinorOpcode);
+    DPMSStandbyTime = DPMSSuspendTime = DPMSOffTime = ScreenSaverTime;
+    DPMSPowerLevel = DPMSModeOn;
+    DPMSEnabled = DPMSSupported();
+
+    if (DPMSEnabled)
+        AddExtension(DPMSExtensionName, 0, 0,
+                     ProcDPMSDispatch, SProcDPMSDispatch,
+                     DPMSCloseDownExtension, StandardMinorOpcode);
 }