From: Alex Deucher Date: Fri, 19 Jul 2013 21:44:43 +0000 (-0400) Subject: drm/radeon: improve dac adjust heuristics for legacy pdac X-Git-Tag: firefly_0821_release~6453^2~1263 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d54b22e585edd4401786e7c02cd85bc97fff5ffb;p=firefly-linux-kernel-4.4.55.git drm/radeon: improve dac adjust heuristics for legacy pdac commit 03ed8cf9b28d886c64c7e705c7bb1a365fd8fb95 upstream. Hopefully avoid more quirks in the future due to bogus vbios dac data. Signed-off-by: Alex Deucher Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/gpu/drm/radeon/radeon_combios.c b/drivers/gpu/drm/radeon/radeon_combios.c index 94303840f650..68ce36056019 100644 --- a/drivers/gpu/drm/radeon/radeon_combios.c +++ b/drivers/gpu/drm/radeon/radeon_combios.c @@ -902,8 +902,10 @@ struct radeon_encoder_primary_dac *radeon_combios_get_primary_dac_info(struct dac = RBIOS8(dac_info + 0x3) & 0xf; p_dac->ps2_pdac_adj = (bg << 8) | (dac); } - /* if the values are all zeros, use the table */ - if (p_dac->ps2_pdac_adj) + /* if the values are zeros, use the table */ + if ((dac == 0) || (bg == 0)) + found = 0; + else found = 1; }