powerpc/qe: Fixup QE_General4 errata

QE_General4 should only round up the divisor iff divisor is > 3.
Rounding up lower divisors makes the error too big, causing USB
on MPC832x to fail.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Acked-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

diff --git a/arch/powerpc/sysdev/qe_lib/qe.c b/arch/powerpc/sysdev/qe_lib/qe.c
index 3363fbc..ceb09cb 100644 (file)
--- a/arch/powerpc/sysdev/qe_lib/qe.c
+++ b/arch/powerpc/sysdev/qe_lib/qe.c
@@ -216,7 +216,7 @@ int qe_setbrg(enum qe_clock brg, unsigned int rate, unsigned int multiplier)
        /* Errata QE_General4, which affects some MPC832x and MPC836x SOCs, says
           that the BRG divisor must be even if you're not using divide-by-16
           mode. */
-       if (!div16 && (divisor & 1))
+       if (!div16 && (divisor & 1) && (divisor > 3))
                divisor++;
 
        tempval = ((divisor - 1) << QE_BRGC_DIVISOR_SHIFT) |