On Saturday 10 March 2018 03:53 AM, Enric Balletbo i Serra wrote:
From: zain wang wzz@rock-chips.com
According to DP spec v1.3 chap 3.5.1.2 Link Training, Link Policy Maker must first detect that the HPD signal is asserted high by the Downstream Device before establishing a link with it.
Reviewed-by: Archit Taneja architt@codeaurora.org
Thanks, Archit
Cc: Stéphane Marchesin marcheu@chromium.org Signed-off-by: zain wang wzz@rock-chips.com Signed-off-by: Sean Paul seanpaul@chromium.org Signed-off-by: Thierry Escande thierry.escande@collabora.com Signed-off-by: Enric Balletbo i Serra enric.balletbo@collabora.com Tested-by: Marek Szyprowski m.szyprowski@samsung.com
drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c index c81733b8185e..92fb9a072cb6 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c @@ -1169,6 +1169,17 @@ static int analogix_dp_set_bridge(struct analogix_dp_device *dp) if (ret) goto out_dp_init;
- /*
* According to DP spec v1.3 chap 3.5.1.2 Link Training,* We should first make sure the HPD signal is asserted high by device* when we want to establish a link with it.*/- ret = analogix_dp_detect_hpd(dp);
- if (ret) {
DRM_ERROR("failed to get hpd single ret = %d\n", ret);goto out_dp_init;- }
- ret = analogix_dp_commit(dp); if (ret) goto out_dp_init;