[PATCH] drm/radeon/kms: fix DVO setup on some r4xx chips

[alexdeucher at gmail.com]

From: Alex Deucher <alexander.deucher at amd.com>

Some r4xx chips have the wrong frev in the
DVOEncoderControl table.  It should always be 1
on r4xx.  Fixes modesetting on DVO on r4xx chips
with the bad frev.

Reported by twied on #radeon.

Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Cc: stable at vger.kernel.org
---
 drivers/gpu/drm/radeon/atombios_encoders.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c b/drivers/gpu/drm/radeon/atombios_encoders.c
index b88c460..5e1d0b5 100644
--- a/drivers/gpu/drm/radeon/atombios_encoders.c
+++ b/drivers/gpu/drm/radeon/atombios_encoders.c
@@ -230,6 +230,10 @@ atombios_dvo_setup(struct drm_encoder *encoder, int action)
 	if (!atom_parse_cmd_header(rdev->mode_info.atom_context, index, &frev, &crev))
 		return;
 
+	/* some R4xx chips have the wrong frev */
+	if (rdev->family <= CHIP_RV410)
+		frev = 1;
+
 	switch (frev) {
 	case 1:
 		switch (crev) {
-- 
1.7.7.5