intelfb: change splitm to be brute force

The old splitm didn't always work use a brute force.

Signed-off-by: Dave Airlie <airlied@linux.ie>

1 files changed, 13 insertions, 11 deletions

diff --git a/drivers/video/intelfb/intelfbhw.c b/drivers/video/intelfb/intelfbhw.c
index bf742aad08e9..d52921931a3e 100644
--- a/drivers/video/intelfb/intelfbhw.c
+++ b/drivers/video/intelfb/intelfbhw.c
@@ -746,20 +746,22 @@ static int
 splitm(int index, unsigned int m, unsigned int *retm1, unsigned int *retm2)
 {
         int m1, m2;
-
-        m1 = (m - 2 - (plls[index].min_m1 + plls[index].max_m2) / 2) / 5 - 2;
-        if (m1 < plls[index].min_m1)
-                m1 = plls[index].min_m1;
-        if (m1 > plls[index].max_m1)
-                m1 = plls[index].max_m1;
-        m2 = m - 5 * (m1 + 2) - 2;
-        if (m2 < plls[index].min_m2 || m2 > plls[index].max_m2 || m2 >= m1) {
-                return 1;
-        } else {
+        int testm;
+        /* no point optimising too much - brute force m */
+        for (m1 = plls[index].min_m1; m1 < plls[index].max_m1+1; m1++)
+        {
+          for (m2 = plls[index].min_m2; m2 < plls[index].max_m2+1; m2++)
+          {
+            testm  = ( 5 * ( m1 + 2 )) + (m2 + 2);
+            if (testm == m)
+            {
                 *retm1 = (unsigned int)m1;
-                *retm2 = (unsigned int)m2;
+                *retm2 = (unsigned int)m2;            
                 return 0;
+            }
+          }
         }
+        return 1;
 }
 
 /* Split the P parameter into P1 and P2. */