Code before looked only at bit 31 to decide if a port is unused. However dcb 4.1 spec says 0x1F in bits 31-27 and 26-22 means unused.
This fixed hdmi monitor detection on GM206. --- drm/nouveau/nvkm/subdev/bios/i2c.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drm/nouveau/nvkm/subdev/bios/i2c.c b/drm/nouveau/nvkm/subdev/bios/i2c.c index d1a89b2..c4e1f08 100644 --- a/drm/nouveau/nvkm/subdev/bios/i2c.c +++ b/drm/nouveau/nvkm/subdev/bios/i2c.c @@ -74,7 +74,11 @@ dcb_i2c_parse(struct nvkm_bios *bios, u8 idx, struct dcb_i2c_entry *info) u16 ent = dcb_i2c_entry(bios, idx, &ver, &len); if (ent) { if (ver >= 0x41) { - if (!(nv_ro32(bios, ent) & 0x80000000)) + u32 ent_value = nv_ro32(bios, ent); + u8 i2c_port = (ent_value >> 27) & 0x1f; + u8 dpaux_port = (ent_value >> 22) & 0x1f; + /* value 0x1f means unused according to DCB 4.x spec */ + if (i2c_port == 0x1f && dpaux_port == 0x1f) info->type = DCB_I2C_UNUSED; else info->type = DCB_I2C_PMGR;