[PATCH] atyfb, rivafb: minor fixes

aty128fb: return an error in the unlikely event that we cannot calculate
some key PLL info

rivafb:
* call CalcStateExt() directly, rather than via function pointers, since
  CalcStateExt() is the only value ever assigned to ->CalcStateExt().
* propagate error return back from CalcVClock() through callers

Signed-off-by: Jeff Garzik <jeff@garzik.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

4 files changed, 43 insertions, 11 deletions

diff --git a/drivers/video/aty/aty128fb.c b/drivers/video/aty/aty128fb.c
index 276a21530b95..3feddf89d100 100644
--- a/drivers/video/aty/aty128fb.c
+++ b/drivers/video/aty/aty128fb.c
@@ -1333,6 +1333,8 @@ static int aty128_var_to_pll(u32 period_in_ps, struct aty128_pll *pll,
         if (vclk * 12 < c.ppll_min)
                 vclk = c.ppll_min/12;
 
+        pll->post_divider = -1;
+
         /* now, find an acceptable divider */
         for (i = 0; i < sizeof(post_dividers); i++) {
                 output_freq = post_dividers[i] * vclk;
@@ -1342,6 +1344,9 @@ static int aty128_var_to_pll(u32 period_in_ps, struct aty128_pll *pll,
                 }
         }
 
+        if (pll->post_divider < 0)
+                return -EINVAL;
+
         /* calculate feedback divider */
         n = c.ref_divider * output_freq;
         d = c.ref_clk;
diff --git a/drivers/video/riva/fbdev.c b/drivers/video/riva/fbdev.c
index c6f86859399c..345e8b1c1af8 100644
--- a/drivers/video/riva/fbdev.c
+++ b/drivers/video/riva/fbdev.c
@@ -740,11 +740,12 @@ static void riva_load_state(struct riva_par *par, struct riva_regs *regs)
  * CALLED FROM:
  * rivafb_set_par()
  */
-static void riva_load_video_mode(struct fb_info *info)
+static int riva_load_video_mode(struct fb_info *info)
 {
         int bpp, width, hDisplaySize, hDisplay, hStart,
             hEnd, hTotal, height, vDisplay, vStart, vEnd, vTotal, dotClock;
         int hBlankStart, hBlankEnd, vBlankStart, vBlankEnd;
+        int rc;
         struct riva_par *par = info->par;
         struct riva_regs newmode;
         
@@ -850,8 +851,10 @@ static void riva_load_video_mode(struct fb_info *info)
         else
                 newmode.misc_output |= 0x80;    
 
-        par->riva.CalcStateExt(&par->riva, &newmode.ext, bpp, width,
-                                  hDisplaySize, height, dotClock);
+        rc = CalcStateExt(&par->riva, &newmode.ext, bpp, width,
+                          hDisplaySize, height, dotClock);
+        if (rc)
+                goto out;
 
         newmode.ext.scale = NV_RD32(par->riva.PRAMDAC, 0x00000848) &
                 0xfff000ff;
@@ -883,8 +886,12 @@ static void riva_load_video_mode(struct fb_info *info)
         par->current_state = newmode;
         riva_load_state(par, &par->current_state);
         par->riva.LockUnlock(&par->riva, 0); /* important for HW cursor */
+
+out:
         rivafb_blank(FB_BLANK_UNBLANK, info);
         NVTRACE_LEAVE();
+
+        return rc;
 }
 
 static void riva_update_var(struct fb_var_screeninfo *var, struct fb_videomode *modedb)
@@ -1252,12 +1259,15 @@ static int rivafb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
 static int rivafb_set_par(struct fb_info *info)
 {
         struct riva_par *par = info->par;
+        int rc = 0;
 
         NVTRACE_ENTER();
         /* vgaHWunlock() + riva unlock (0x7F) */
         CRTCout(par, 0x11, 0xFF);
         par->riva.LockUnlock(&par->riva, 0);
-        riva_load_video_mode(info);
+        rc = riva_load_video_mode(info);
+        if (rc)
+                goto out;
         if(!(info->flags & FBINFO_HWACCEL_DISABLED))
                 riva_setup_accel(info);
         
@@ -1270,8 +1280,10 @@ static int rivafb_set_par(struct fb_info *info)
                 info->pixmap.scan_align = 1;
         else
                 info->pixmap.scan_align = 4;
+
+out:
         NVTRACE_LEAVE();
-        return 0;
+        return rc;
 }
 
 /**
diff --git a/drivers/video/riva/riva_hw.c b/drivers/video/riva/riva_hw.c
index b6f8690b96c9..e0b8c521cc9c 100644
--- a/drivers/video/riva/riva_hw.c
+++ b/drivers/video/riva/riva_hw.c
@@ -1227,7 +1227,7 @@ static int CalcVClock
  * Calculate extended mode parameters (SVGA) and save in a 
  * mode state structure.
  */
-static void CalcStateExt
+int CalcStateExt
 (
     RIVA_HW_INST  *chip,
     RIVA_HW_STATE *state,
@@ -1249,7 +1249,8 @@ static void CalcStateExt
      * Extended RIVA registers.
      */
     pixelDepth = (bpp + 1)/8;
-    CalcVClock(dotClock, &VClk, &m, &n, &p, chip);
+    if (!CalcVClock(dotClock, &VClk, &m, &n, &p, chip))
+        return -EINVAL;
 
     switch (chip->Architecture)
     {
@@ -1327,6 +1328,8 @@ static void CalcStateExt
     state->pitch1   =
     state->pitch2   =
     state->pitch3   = pixelDepth * width;
+
+    return 0;
 }
 /*
  * Load fixed function state and pre-calculated/stored state.
@@ -2026,7 +2029,6 @@ static void nv3GetConfig
      */
     chip->Busy            = nv3Busy;
     chip->ShowHideCursor  = ShowHideCursor;
-    chip->CalcStateExt    = CalcStateExt;
     chip->LoadStateExt    = LoadStateExt;
     chip->UnloadStateExt  = UnloadStateExt;
     chip->SetStartAddress = SetStartAddress3;
@@ -2084,7 +2086,6 @@ static void nv4GetConfig
      */
     chip->Busy            = nv4Busy;
     chip->ShowHideCursor  = ShowHideCursor;
-    chip->CalcStateExt    = CalcStateExt;
     chip->LoadStateExt    = LoadStateExt;
     chip->UnloadStateExt  = UnloadStateExt;
     chip->SetStartAddress = SetStartAddress;
@@ -2186,7 +2187,6 @@ static void nv10GetConfig
      */
     chip->Busy            = nv10Busy;
     chip->ShowHideCursor  = ShowHideCursor;
-    chip->CalcStateExt    = CalcStateExt;
     chip->LoadStateExt    = LoadStateExt;
     chip->UnloadStateExt  = UnloadStateExt;
     chip->SetStartAddress = SetStartAddress;
diff --git a/drivers/video/riva/riva_hw.h b/drivers/video/riva/riva_hw.h
index a1e71a626df2..c2769f73e0b2 100644
--- a/drivers/video/riva/riva_hw.h
+++ b/drivers/video/riva/riva_hw.h
@@ -463,7 +463,6 @@ typedef struct _riva_hw_inst
      * Common chip functions.
      */
     int  (*Busy)(struct _riva_hw_inst *);
-    void (*CalcStateExt)(struct _riva_hw_inst *,struct _riva_hw_state *,int,int,int,int,int);
     void (*LoadStateExt)(struct _riva_hw_inst *,struct _riva_hw_state *);
     void (*UnloadStateExt)(struct _riva_hw_inst *,struct _riva_hw_state *);
     void (*SetStartAddress)(struct _riva_hw_inst *,U032);
@@ -528,6 +527,22 @@ typedef struct _riva_hw_state
     U032 pitch2;
     U032 pitch3;
 } RIVA_HW_STATE;
+
+/*
+ * function prototypes
+ */
+
+extern int CalcStateExt
+(
+    RIVA_HW_INST  *chip,
+    RIVA_HW_STATE *state,
+    int            bpp,
+    int            width,
+    int            hDisplaySize,
+    int            height,
+    int            dotClock
+);
+
 /*
  * External routines.
  */