Add a return value to load_cursor_argb() to allow it to report failure

load_cursor_argb() may need to be able to fail and have the server fall back
to a software cursor in at least the following circumstances.
1) The hardware can only support some ARGB cursors and this does not just
depend on cursor size.
2) Virtual hardware may not wish to pass through a cursor to the host at a
particular time but may wish to accept the same cursor at another time.
This patch adds a return value to the API and makes the server do the
software fall-back on failure.

Signed-off-by: Michael Thayer <michael.thayer@oracle.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>

9 files changed, 49 insertions, 33 deletions

diff --git a/hw/xfree86/common/xf86Module.h b/hw/xfree86/common/xf86Module.h
index e8c24f26c..62ac95d5a 100644
--- a/hw/xfree86/common/xf86Module.h
+++ b/hw/xfree86/common/xf86Module.h
@@ -80,7 +80,7 @@ typedef enum {
  * mask is 0xFFFF0000.
  */
 #define ABI_ANSIC_VERSION	SET_ABI_VERSION(0, 4)
-#define ABI_VIDEODRV_VERSION	SET_ABI_VERSION(16, 0)
+#define ABI_VIDEODRV_VERSION	SET_ABI_VERSION(17, 0)
 #define ABI_XINPUT_VERSION	SET_ABI_VERSION(21, 0)
 #define ABI_EXTENSION_VERSION	SET_ABI_VERSION(8, 0)
 #define ABI_FONT_VERSION	SET_ABI_VERSION(0, 6)
diff --git a/hw/xfree86/modes/xf86Crtc.h b/hw/xfree86/modes/xf86Crtc.h
index c127d78af..5407deb0e 100644
--- a/hw/xfree86/modes/xf86Crtc.h
+++ b/hw/xfree86/modes/xf86Crtc.h
@@ -186,13 +186,13 @@ typedef struct _xf86CrtcFuncs {
     /**
      * Load monochrome image
      */
-    void
+    Bool
      (*load_cursor_image) (xf86CrtcPtr crtc, CARD8 *image);
 
     /**
      * Load ARGB image
      */
-    void
+    Bool
      (*load_cursor_argb) (xf86CrtcPtr crtc, CARD32 *image);
 
     /**
diff --git a/hw/xfree86/modes/xf86Cursors.c b/hw/xfree86/modes/xf86Cursors.c
index 2b0db3492..10ef6f6d4 100644
--- a/hw/xfree86/modes/xf86Cursors.c
+++ b/hw/xfree86/modes/xf86Cursors.c
@@ -211,7 +211,7 @@ set_bit(CARD8 *image, xf86CursorInfoPtr cursor_info, int x, int y, Bool mask)
 /*
  * Load a two color cursor into a driver that supports only ARGB cursors
  */
-static void
+static Bool
 xf86_crtc_convert_cursor_to_argb(xf86CrtcPtr crtc, unsigned char *src)
 {
     ScrnInfoPtr scrn = crtc->scrn;
@@ -244,7 +244,7 @@ xf86_crtc_convert_cursor_to_argb(xf86CrtcPtr crtc, unsigned char *src)
                 bits = 0;
             cursor_image[y * cursor_info->MaxWidth + x] = bits;
         }
-    crtc->funcs->load_cursor_argb(crtc, cursor_image);
+    return crtc->funcs->load_cursor_argb(crtc, cursor_image);
 }
 
 /*
@@ -415,7 +415,7 @@ xf86_set_cursor_position(ScrnInfoPtr scrn, int x, int y)
 /*
  * Load a two-color cursor into a crtc, performing rotation as needed
  */
-static void
+static Bool
 xf86_crtc_load_cursor_image(xf86CrtcPtr crtc, CARD8 *src)
 {
     ScrnInfoPtr scrn = crtc->scrn;
@@ -450,13 +450,13 @@ xf86_crtc_load_cursor_image(xf86CrtcPtr crtc, CARD8 *src)
                     set_bit(cursor_image, cursor_info, x, y, TRUE);
             }
     }
-    crtc->funcs->load_cursor_image(crtc, cursor_image);
+    return crtc->funcs->load_cursor_image(crtc, cursor_image);
 }
 
 /*
  * Load a cursor image into all active CRTCs
  */
-static void
+static Bool
 xf86_load_cursor_image(ScrnInfoPtr scrn, unsigned char *src)
 {
     xf86CrtcConfigPtr xf86_config = XF86_CRTC_CONFIG_PTR(scrn);
@@ -466,12 +466,17 @@ xf86_load_cursor_image(ScrnInfoPtr scrn, unsigned char *src)
         xf86CrtcPtr crtc = xf86_config->crtc[c];
 
         if (crtc->enabled) {
-            if (crtc->funcs->load_cursor_image)
-                xf86_crtc_load_cursor_image(crtc, src);
-            else if (crtc->funcs->load_cursor_argb)
-                xf86_crtc_convert_cursor_to_argb(crtc, src);
+            if (crtc->funcs->load_cursor_image) {
+                if (!xf86_crtc_load_cursor_image(crtc, src))
+                    return FALSE;
+            } else if (crtc->funcs->load_cursor_argb) {
+                if (!xf86_crtc_convert_cursor_to_argb(crtc, src))
+                    return FALSE;
+            } else
+                return FALSE;
         }
     }
+    return TRUE;
 }
 
 static Bool
@@ -516,7 +521,7 @@ xf86_use_hw_cursor_argb(ScreenPtr screen, CursorPtr cursor)
     return TRUE;
 }
 
-static void
+static Bool
 xf86_crtc_load_cursor_argb(xf86CrtcPtr crtc, CursorPtr cursor)
 {
     ScrnInfoPtr scrn = crtc->scrn;
@@ -544,10 +549,10 @@ xf86_crtc_load_cursor_argb(xf86CrtcPtr crtc, CursorPtr cursor)
             cursor_image[y * image_width + x] = bits;
         }
 
-    crtc->funcs->load_cursor_argb(crtc, cursor_image);
+    return crtc->funcs->load_cursor_argb(crtc, cursor_image);
 }
 
-static void
+static Bool
 xf86_load_cursor_argb(ScrnInfoPtr scrn, CursorPtr cursor)
 {
     xf86CrtcConfigPtr xf86_config = XF86_CRTC_CONFIG_PTR(scrn);
@@ -557,8 +562,10 @@ xf86_load_cursor_argb(ScrnInfoPtr scrn, CursorPtr cursor)
         xf86CrtcPtr crtc = xf86_config->crtc[c];
 
         if (crtc->enabled)
-            xf86_crtc_load_cursor_argb(crtc, cursor);
+            if (!xf86_crtc_load_cursor_argb(crtc, cursor))
+                return FALSE;
     }
+    return TRUE;
 }
 
 Bool
@@ -608,6 +615,8 @@ xf86_cursors_init(ScreenPtr screen, int max_width, int max_height, int flags)
  * Called when anything on the screen is reconfigured.
  *
  * Reloads cursor images as needed, then adjusts cursor positions
+ * @note We assume that all hardware cursors to be loaded have already been
+ *       found to be usable by the hardware.
  */
 
 void
diff --git a/hw/xfree86/ramdac/IBM.c b/hw/xfree86/ramdac/IBM.c
index bc716231a..872d3d4e7 100644
--- a/hw/xfree86/ramdac/IBM.c
+++ b/hw/xfree86/ramdac/IBM.c
@@ -570,7 +570,7 @@ IBMramdac640SetCursorColors(ScrnInfoPtr pScrn, int bg, int fg)
     (*ramdacPtr->WriteData) (pScrn, bg);
 }
 
-static void
+static Bool
 IBMramdac526LoadCursorImage(ScrnInfoPtr pScrn, unsigned char *src)
 {
     RamDacRecPtr ramdacPtr = RAMDACSCRPTR(pScrn);
@@ -582,9 +582,10 @@ IBMramdac526LoadCursorImage(ScrnInfoPtr pScrn, unsigned char *src)
      */
     for (i = 0; i < 1024; i++)
         (*ramdacPtr->WriteDAC) (pScrn, IBMRGB_curs_array + i, 0x00, (*src++));
+    return TRUE;
 }
 
-static void
+static Bool
 IBMramdac640LoadCursorImage(ScrnInfoPtr pScrn, unsigned char *src)
 {
     RamDacRecPtr ramdacPtr = RAMDACSCRPTR(pScrn);
@@ -596,6 +597,7 @@ IBMramdac640LoadCursorImage(ScrnInfoPtr pScrn, unsigned char *src)
      */
     for (i = 0; i < 1024; i++)
         (*ramdacPtr->WriteDAC) (pScrn, RGB640_CURS_WRITE + i, 0x00, (*src++));
+    return TRUE;
 }
 
 static Bool
diff --git a/hw/xfree86/ramdac/TI.c b/hw/xfree86/ramdac/TI.c
index 393b774d4..7d4e0d796 100644
--- a/hw/xfree86/ramdac/TI.c
+++ b/hw/xfree86/ramdac/TI.c
@@ -642,7 +642,7 @@ TIramdacSetCursorColors(ScrnInfoPtr pScrn, int bg, int fg)
     (*ramdacPtr->WriteDAC) (pScrn, TIDAC_CURS_COLOR, 0, (fg & 0x000000ff));
 }
 
-static void
+static Bool
 TIramdacLoadCursorImage(ScrnInfoPtr pScrn, unsigned char *src)
 {
     RamDacRecPtr ramdacPtr = RAMDACSCRPTR(pScrn);
@@ -657,6 +657,7 @@ TIramdacLoadCursorImage(ScrnInfoPtr pScrn, unsigned char *src)
         /* NOT_DONE: might need a delay here */
         (*ramdacPtr->WriteDAC) (pScrn, TIDAC_CURS_RAM_DATA, 0, *(src++));
     }
+    return TRUE;
 }
 
 static Bool
diff --git a/hw/xfree86/ramdac/xf86Cursor.c b/hw/xfree86/ramdac/xf86Cursor.c
index 860704e1c..fac682210 100644
--- a/hw/xfree86/ramdac/xf86Cursor.c
+++ b/hw/xfree86/ramdac/xf86Cursor.c
@@ -352,12 +352,13 @@ xf86CursorSetCursor(DeviceIntPtr pDev, ScreenPtr pScreen, CursorPtr pCurs,
                 (*ScreenPriv->spriteFuncs->SetCursor) (pDev, pScreen,
                                                        NullCursor, x, y);
 
-            xf86SetCursor(pScreen, cursor, x, y);
-            ScreenPriv->SWCursor = FALSE;
-            ScreenPriv->isUp = TRUE;
+            if (xf86SetCursor(pScreen, cursor, x, y)) {
+                ScreenPriv->SWCursor = FALSE;
+                ScreenPriv->isUp = TRUE;
 
-            miPointerSetWaitForUpdate(pScreen, !infoPtr->pScrn->silkenMouse);
-            return;
+                miPointerSetWaitForUpdate(pScreen, !infoPtr->pScrn->silkenMouse);
+                return;
+            }
         }
 
         miPointerSetWaitForUpdate(pScreen, TRUE);
diff --git a/hw/xfree86/ramdac/xf86Cursor.h b/hw/xfree86/ramdac/xf86Cursor.h
index 5658e7b30..1ecbdcd8d 100644
--- a/hw/xfree86/ramdac/xf86Cursor.h
+++ b/hw/xfree86/ramdac/xf86Cursor.h
@@ -12,7 +12,7 @@ typedef struct _xf86CursorInfoRec {
     int MaxHeight;
     void (*SetCursorColors) (ScrnInfoPtr pScrn, int bg, int fg);
     void (*SetCursorPosition) (ScrnInfoPtr pScrn, int x, int y);
-    void (*LoadCursorImage) (ScrnInfoPtr pScrn, unsigned char *bits);
+    Bool (*LoadCursorImage) (ScrnInfoPtr pScrn, unsigned char *bits);
     void (*HideCursor) (ScrnInfoPtr pScrn);
     void (*ShowCursor) (ScrnInfoPtr pScrn);
     unsigned char *(*RealizeCursor) (struct _xf86CursorInfoRec *, CursorPtr);
@@ -20,7 +20,7 @@ typedef struct _xf86CursorInfoRec {
 
 #ifdef ARGB_CURSOR
     Bool (*UseHWCursorARGB) (ScreenPtr, CursorPtr);
-    void (*LoadCursorARGB) (ScrnInfoPtr, CursorPtr);
+    Bool (*LoadCursorARGB) (ScrnInfoPtr, CursorPtr);
 #endif
 
 } xf86CursorInfoRec, *xf86CursorInfoPtr;
diff --git a/hw/xfree86/ramdac/xf86CursorPriv.h b/hw/xfree86/ramdac/xf86CursorPriv.h
index a5d2aabc3..f34c1c7fc 100644
--- a/hw/xfree86/ramdac/xf86CursorPriv.h
+++ b/hw/xfree86/ramdac/xf86CursorPriv.h
@@ -37,7 +37,7 @@ typedef struct {
     void *transparentData;
 } xf86CursorScreenRec, *xf86CursorScreenPtr;
 
-void xf86SetCursor(ScreenPtr pScreen, CursorPtr pCurs, int x, int y);
+Bool xf86SetCursor(ScreenPtr pScreen, CursorPtr pCurs, int x, int y);
 void xf86SetTransparentCursor(ScreenPtr pScreen);
 void xf86MoveCursor(ScreenPtr pScreen, int x, int y);
 void xf86RecolorCursor(ScreenPtr pScreen, CursorPtr pCurs, Bool displayed);
diff --git a/hw/xfree86/ramdac/xf86HWCurs.c b/hw/xfree86/ramdac/xf86HWCurs.c
index 3b69698db..0b5caa20a 100644
--- a/hw/xfree86/ramdac/xf86HWCurs.c
+++ b/hw/xfree86/ramdac/xf86HWCurs.c
@@ -119,7 +119,7 @@ xf86InitHardwareCursor(ScreenPtr pScreen, xf86CursorInfoPtr infoPtr)
     return TRUE;
 }
 
-void
+Bool
 xf86SetCursor(ScreenPtr pScreen, CursorPtr pCurs, int x, int y)
 {
     xf86CursorScreenPtr ScreenPriv =
@@ -130,7 +130,7 @@ xf86SetCursor(ScreenPtr pScreen, CursorPtr pCurs, int x, int y)
 
     if (pCurs == NullCursor) {
         (*infoPtr->HideCursor) (infoPtr->pScrn);
-        return;
+        return TRUE;
     }
 
     bits =
@@ -152,18 +152,21 @@ xf86SetCursor(ScreenPtr pScreen, CursorPtr pCurs, int x, int y)
         (*infoPtr->HideCursor) (infoPtr->pScrn);
 
 #ifdef ARGB_CURSOR
-    if (pCurs->bits->argb && infoPtr->LoadCursorARGB)
-        (*infoPtr->LoadCursorARGB) (infoPtr->pScrn, pCurs);
-    else
+    if (pCurs->bits->argb && infoPtr->LoadCursorARGB) {
+        if (!(*infoPtr->LoadCursorARGB) (infoPtr->pScrn, pCurs))
+            return FALSE;
+    } else
 #endif
     if (bits)
-        (*infoPtr->LoadCursorImage) (infoPtr->pScrn, bits);
+        if (!(*infoPtr->LoadCursorImage) (infoPtr->pScrn, bits))
+            return FALSE;
 
     xf86RecolorCursor(pScreen, pCurs, 1);
 
     (*infoPtr->SetCursorPosition) (infoPtr->pScrn, x, y);
 
     (*infoPtr->ShowCursor) (infoPtr->pScrn);
+    return TRUE;
 }
 
 void