viafb: fix IGA1 modesetting on VX900

Even if the documentation calls this bit "Reserved" it has to be set
to 0 for correct modesetting on IGA1.

Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: stable@vger.kernel.org

diff --git a/drivers/video/via/hw.c b/drivers/video/via/hw.c
index 8bdf80e..8497727 100644 (file)
--- a/drivers/video/via/hw.c
+++ b/drivers/video/via/hw.c
@@ -1810,6 +1810,9 @@ static void hw_init(void)
                break;
        }
 
+       /* magic required on VX900 for correct modesetting on IGA1 */
+       via_write_reg_mask(VIACR, 0x45, 0x00, 0x01);
+
        /* probably this should go to the scaling code one day */
        via_write_reg_mask(VIACR, 0xFD, 0, 0x80); /* VX900 hw scale on IGA2 */
        viafb_write_regx(scaling_parameters, ARRAY_SIZE(scaling_parameters));