From 5a6f690ca565f536ab0fc05e267b08d5a7c36b46 Mon Sep 17 00:00:00 2001 From: Stefan Huehner Date: Sun, 22 Feb 2015 15:46:36 +0100 Subject: [PATCH] drm/nouveau/bios: fix i2c table parsing for dcb 4.1 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. Signed-off-by: Ben Skeggs --- drivers/gpu/drm/nouveau/nvkm/subdev/bios/i2c.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/bios/i2c.c b/drivers/gpu/drm/nouveau/nvkm/subdev/bios/i2c.c index d1a89b2bd5c1..c4e1f085ee10 100644 --- a/drivers/gpu/drm/nouveau/nvkm/subdev/bios/i2c.c +++ b/drivers/gpu/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;