Allow RandR get output property to call into drivers

In order to report accurate values to users of the RandR property interface,
it's sometimes necessary to ask the driver to update the value (for example
when backlight brightness changes without the server's knowledge, due to hotkey
events or direct sysfs banging).

This patch wires up the core server code with a new xf86CrtcFuncs callback,
get_property, to allow for this.

The new code is available under the RANDR_13_INTERFACE define, which in turn
depends on the RANDR_12_INTERFACE code.

3 files changed, 34 insertions, 6 deletions

diff --git a/randr/mirandr.c b/randr/mirandr.c
index 3c4991e5a..777785380 100644
--- a/randr/mirandr.c
+++ b/randr/mirandr.c
@@ -74,6 +74,14 @@ miRROutputSetProperty (ScreenPtr	    pScreen,
 }
 
 Bool
+miRROutputGetProperty (ScreenPtr	    pScreen,
+		       RROutputPtr	    output,
+		       Atom		    property)
+{
+	return TRUE;
+}
+
+Bool
 miRROutputValidateMode (ScreenPtr	    pScreen,
 			RROutputPtr	    output,
 			RRModePtr	    mode)
@@ -116,6 +124,9 @@ miRandRInit (ScreenPtr pScreen)
     pScrPriv->rrCrtcSet = miRRCrtcSet;
     pScrPriv->rrCrtcSetGamma = miRRCrtcSetGamma;
     pScrPriv->rrOutputSetProperty = miRROutputSetProperty;
+#if RANDR_13_INTERFACE
+    pScrPriv->rrOutputGetProperty = miRROutputGetProperty;
+#endif
     pScrPriv->rrOutputValidateMode = miRROutputValidateMode;
     pScrPriv->rrModeDestroy = miRRModeDestroy;
     
diff --git a/randr/randrstr.h b/randr/randrstr.h
index e8358bc0c..3b48f5c2b 100644
--- a/randr/randrstr.h
+++ b/randr/randrstr.h
@@ -54,6 +54,7 @@
 /* required for ABI compatibility for now */
 #define RANDR_10_INTERFACE 1
 #define RANDR_12_INTERFACE 1
+#define RANDR_13_INTERFACE 1 /* requires RANDR_12_INTERFACE */
 
 typedef XID	RRMode;
 typedef XID	RROutput;
@@ -175,6 +176,12 @@ typedef void (*RRModeDestroyProcPtr) (ScreenPtr	    pScreen,
 
 #endif
 
+#if RANDR_13_INTERFACE
+typedef Bool (*RROutputGetPropertyProcPtr) (ScreenPtr		pScreen,
+					    RROutputPtr		output,
+					    Atom		property);
+#endif /* RANDR_13_INTERFACE */
+
 typedef Bool (*RRGetInfoProcPtr) (ScreenPtr pScreen, Rotation *rotations);
 typedef Bool (*RRCloseScreenProcPtr) ( int i, ScreenPtr pscreen);
 
@@ -220,6 +227,9 @@ typedef struct _rrScrPriv {
     RROutputValidateModeProcPtr	rrOutputValidateMode;
     RRModeDestroyProcPtr	rrModeDestroy;
 #endif
+#if RANDR_13_INTERFACE
+    RROutputGetPropertyProcPtr	rrOutputGetProperty;
+#endif
     
     /*
      * Private part of the structure; not considered part of the ABI
diff --git a/randr/rrproperty.c b/randr/rrproperty.c
index 4617064e4..9bb7081ca 100644
--- a/randr/rrproperty.c
+++ b/randr/rrproperty.c
@@ -300,13 +300,21 @@ RRPropertyValuePtr
 RRGetOutputProperty (RROutputPtr output, Atom property, Bool pending)
 {
     RRPropertyPtr   prop = RRQueryOutputProperty (output, property);
+    rrScrPrivPtr    pScrPriv = rrGetScrPriv(output->pScreen);
 
     if (!prop)
 	return NULL;
     if (pending && prop->is_pending)
 	return &prop->pending;
-    else
+    else {
+#if RANDR_13_INTERFACE
+	/* If we can, try to update the property value first */
+	if (pScrPriv->rrOutputGetProperty)
+	    pScrPriv->rrOutputGetProperty(output->pScreen, output,
+					  prop->propertyName);
+#endif
 	return &prop->current;
+    }
 }
 
 int
@@ -610,11 +618,10 @@ ProcRRGetOutputProperty (ClientPtr client)
     if (prop->immutable && stuff->delete)
 	return BadAccess;
 
-    if (stuff->pending && prop->is_pending)
-	prop_value = &prop->pending;
-    else
-	prop_value = &prop->current;
-    
+    prop_value = RRGetOutputProperty(output, stuff->property, stuff->pending);
+    if (!prop_value)
+	return BadAtom;
+
     /* If the request type and actual type don't match. Return the
     property information, but not the data. */