From: Tom Rix <t...@redhat.com> [ Upstream commit cdd296cdae1af2d27dae3fcfbdf12c5252ab78cf ]
Reviewing this block of code in cdv_intel_dp_init() ret = cdv_intel_dp_aux_native_read(gma_encoder, DP_DPCD_REV, ... cdv_intel_edp_panel_vdd_off(gma_encoder); if (ret == 0) { /* if this fails, presume the device is a ghost */ DRM_INFO("failed to retrieve link info, disabling eDP\n"); drm_encoder_cleanup(encoder); cdv_intel_dp_destroy(connector); goto err_priv; } else { The (ret == 0) is not strict enough. cdv_intel_dp_aux_native_read() returns > 0 on success otherwise it is failure. So change to <= Fixes: d112a8163f83 ("gma500/cdv: Add eDP support") Signed-off-by: Tom Rix <t...@redhat.com> Signed-off-by: Patrik Jakobsson <patrik.r.jakobs...@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200805205911.20927-1-t...@redhat.com Signed-off-by: Sasha Levin <sas...@kernel.org> --- drivers/gpu/drm/gma500/cdv_intel_dp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/gma500/cdv_intel_dp.c b/drivers/gpu/drm/gma500/cdv_intel_dp.c index 90ed20083009f..05eba6dec5ebf 100644 --- a/drivers/gpu/drm/gma500/cdv_intel_dp.c +++ b/drivers/gpu/drm/gma500/cdv_intel_dp.c @@ -2119,7 +2119,7 @@ cdv_intel_dp_init(struct drm_device *dev, struct psb_intel_mode_device *mode_dev intel_dp->dpcd, sizeof(intel_dp->dpcd)); cdv_intel_edp_panel_vdd_off(gma_encoder); - if (ret == 0) { + if (ret <= 0) { /* if this fails, presume the device is a ghost */ DRM_INFO("failed to retrieve link info, disabling eDP\n"); cdv_intel_dp_encoder_destroy(encoder); -- 2.25.1