drm/nouveau: Don't try DDC on the dummy I2C channel.

Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
index b1b22baf1428..a1473fff06ac 100644
--- a/drivers/gpu/drm/nouveau/nouveau_connector.c
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
@@ -104,7 +104,7 @@ nouveau_connector_ddc_detect(struct drm_connector *connector,
         int i;
 
         for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
-                struct nouveau_i2c_chan *i2c;
+                struct nouveau_i2c_chan *i2c = NULL;
                 struct nouveau_encoder *nv_encoder;
                 struct drm_mode_object *obj;
                 int id;
@@ -117,7 +117,9 @@ nouveau_connector_ddc_detect(struct drm_connector *connector,
                 if (!obj)
                         continue;
                 nv_encoder = nouveau_encoder(obj_to_encoder(obj));
-                i2c = nouveau_i2c_find(dev, nv_encoder->dcb->i2c_index);
+
+                if (nv_encoder->dcb->i2c_index < 0xf)
+                        i2c = nouveau_i2c_find(dev, nv_encoder->dcb->i2c_index);
 
                 if (i2c && nouveau_probe_i2c_addr(i2c, 0x50)) {
                         *pnv_encoder = nv_encoder;