video: tegra: dp: eDP/miniDP support

To add a support for an internal eDP panel or an external DP
monitor

- reduce the HPD waiting time to reasonable
- fix Alternate Scrambler Reset To 0xFFFE setting to support an
  external DP monitor
- fix unplugged eDP/miniDP display at boot time blocking detection
  of the HDMI display
- disable dpaux clock and pad power when no eDP panel or external
  monitor connected at boot time

Note: It works with the eDP panel or the monitor connected only at
      boot time.  No run-time hot plug support yet.
Note2: Reposting due the Gerrit bug.

bug 1409738

Change-Id: I81b8bab8881a6d849d97562deabd16fe794ff812
Signed-off-by: Sungwook Kim <sungwookk@nvidia.com>
Reviewed-on: http://git-master/r/405512
(cherry picked from commit 199b1034b39f2a133623e5645e378c5a9abd1c81)
Reviewed-on: http://git-master/r/420122
Reviewed-by: Mandar Padmawar <mpadmawar@nvidia.com>
Tested-by: Mandar Padmawar <mpadmawar@nvidia.com>

2 files changed, 38 insertions, 2 deletions

diff --git a/drivers/video/tegra/dc/dc.c b/drivers/video/tegra/dc/dc.c
index fe106d1c61b5..3b8d807e9c03 100644
--- a/drivers/video/tegra/dc/dc.c
+++ b/drivers/video/tegra/dc/dc.c
@@ -1450,6 +1450,9 @@ static int tegra_dc_set_out(struct tegra_dc *dc, struct tegra_dc_out *out)
 		if (err < 0) {
 			dc->out = NULL;
 			dc->out_ops = NULL;
+			dev_err(&dc->ndev->dev,
+				"Error: out->type:%d out_ops->init() failed\n",
+				out->type);
 			return err;
 		}
 	}
@@ -2255,6 +2258,9 @@ static int tegra_dc_init(struct tegra_dc *dc)
 		if (!dc->initialized) {
 			if (tegra_dc_program_mode(dc, &dc->mode)) {
 				tegra_dc_io_end(dc);
+				dev_warn(&dc->ndev->dev,
+					"%s: tegra_dc_program_mode failed\n",
+					__func__);
 				return -EINVAL;
 			}
 		} else {
@@ -2314,6 +2320,8 @@ static bool _tegra_dc_controller_enable(struct tegra_dc *dc)
 			tegra_dc_clk_disable(dc);
 		else
 			tegra_dvfs_set_rate(dc->clk, 0);
+		dev_warn(&dc->ndev->dev,
+			"%s: tegra_dc_init failed\n", __func__);
 		return false;
 	}
 
diff --git a/drivers/video/tegra/dc/dp.c b/drivers/video/tegra/dc/dp.c
index ebb7b46ad4fa..2e47617d3006 100644
--- a/drivers/video/tegra/dc/dp.c
+++ b/drivers/video/tegra/dc/dp.c
@@ -778,6 +778,8 @@ static void tegra_dc_dp_dump_link_cfg(struct tegra_dc_dp_data *dp,
 		cfg->max_lane_count);
 	dev_info(&dp->dc->ndev->dev, "           SupportEnhancedFraming %s\n",
 		cfg->support_enhanced_framing ? "Y" : "N");
+	dev_info(&dp->dc->ndev->dev, "           SupportAltScrmbRstFffe %s\n",
+		cfg->alt_scramber_reset_cap ? "Y" : "N");
 	dev_info(&dp->dc->ndev->dev, "           Bandwidth              %d\n",
 		cfg->max_link_bw);
 	dev_info(&dp->dc->ndev->dev, "           bpp                    %d\n",
@@ -1528,7 +1530,7 @@ static void tegra_dp_hpd_config(struct tegra_dc_dp_data *dp)
 
 static int tegra_dp_hpd_plug(struct tegra_dc_dp_data *dp)
 {
-#define TEGRA_DP_HPD_PLUG_TIMEOUT_MS	10000
+#define TEGRA_DP_HPD_PLUG_TIMEOUT_MS	500
 	u32 val;
 	int err = 0;
 
@@ -2002,6 +2004,8 @@ static void tegra_dp_link_config(struct tegra_dc_dp_data *dp)
 
 	if (cfg->alt_scramber_reset_cap)
 		tegra_dc_dp_set_assr(dp, true);
+	else
+		tegra_dc_sor_set_internal_panel(dp->sor, false);
 
 	tegra_dc_dp_dpcd_write(dp, NV_DPCD_MAIN_LINK_CHANNEL_CODING_SET,
 			NV_DPCD_MAIN_LINK_CHANNEL_CODING_SET_ANSI_8B10B);
@@ -2085,7 +2089,7 @@ static void tegra_dc_dp_enable(struct tegra_dc *dc)
 
 	tegra_dp_hpd_config(dp);
 	if (tegra_dp_hpd_plug(dp) < 0) {
-		dev_err(&dc->ndev->dev, "dp: hpd plug failed\n");
+		dev_info(&dc->ndev->dev, "dp: no panel/monitor plugged\n");
 		goto error_enable;
 	}
 
@@ -2109,9 +2113,14 @@ static void tegra_dc_dp_enable(struct tegra_dc *dc)
 
 	tegra_dc_sor_attach(dp->sor);
 	dp->enabled = true;
+	tegra_dp_default_int(dp, false);
+	tegra_dc_io_end(dc);
+	return;
 
 error_enable:
 	tegra_dp_default_int(dp, false);
+	tegra_dpaux_pad_power(dp->dc, false);
+	tegra_dpaux_clk_disable(dp);
 	tegra_dc_io_end(dc);
 	return;
 }
@@ -2178,6 +2187,24 @@ static long tegra_dc_dp_setup_clk(struct tegra_dc *dc, struct clk *clk)
 	return tegra_dc_pclk_round_rate(dc, dc->mode.pclk);
 }
 
+/* used by tegra_dc_probe() to detect connection(HPD) status at boot */
+static bool tegra_dc_dp_detect(struct tegra_dc *dc)
+{
+	struct tegra_dc_dp_data *dp = tegra_dc_get_outdata(dc);
+	u32 rd;
+
+	tegra_dc_io_start(dc);
+	tegra_dpaux_clk_enable(dp);
+	rd = tegra_dpaux_readl(dp, DPAUX_DP_AUXSTAT);
+	tegra_dpaux_clk_disable(dp);
+	tegra_dc_io_end(dc);
+	dev_info(&dc->ndev->dev,
+		"dp: DPAUX_DP_AUXSTAT:0x%08x HPD:%splugged\n",
+		rd, (DPAUX_DP_AUXSTAT_HPD_STATUS_PLUGGED & rd) ? "" : "un");
+	return (DPAUX_DP_AUXSTAT_HPD_STATUS_PLUGGED & rd) ? true : false;
+}
+
+
 static void tegra_dc_dp_modeset_notifier(struct tegra_dc *dc)
 {
 	struct tegra_dc_dp_data *dp = tegra_dc_get_outdata(dc);
@@ -2196,6 +2223,7 @@ struct tegra_dc_out_ops tegra_dc_dp_ops = {
 	.destroy   = tegra_dc_dp_destroy,
 	.enable	   = tegra_dc_dp_enable,
 	.disable   = tegra_dc_dp_disable,
+	.detect    = tegra_dc_dp_detect,
 	.setup_clk = tegra_dc_dp_setup_clk,
 	.modeset_notifier = tegra_dc_dp_modeset_notifier,
 };