1 files changed, 43 insertions, 0 deletions

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_group.c b/drivers/gpu/drm/rcar-du/rcar_du_group.c
index 7e440f61977f..9eee47969e77 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_group.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_group.c
@@ -287,6 +287,47 @@ int rcar_du_set_dpad0_vsp1_routing(struct rcar_du_device *rcdu)
         return 0;
 }
 
+static void rcar_du_group_set_dpad_levels(struct rcar_du_group *rgrp)
+{
+        static const u32 doflr_values[2] = {
+                DOFLR_HSYCFL0 | DOFLR_VSYCFL0 | DOFLR_ODDFL0 |
+                DOFLR_DISPFL0 | DOFLR_CDEFL0  | DOFLR_RGBFL0,
+                DOFLR_HSYCFL1 | DOFLR_VSYCFL1 | DOFLR_ODDFL1 |
+                DOFLR_DISPFL1 | DOFLR_CDEFL1  | DOFLR_RGBFL1,
+        };
+        static const u32 dpad_mask = BIT(RCAR_DU_OUTPUT_DPAD1)
+                                   | BIT(RCAR_DU_OUTPUT_DPAD0);
+        struct rcar_du_device *rcdu = rgrp->dev;
+        u32 doflr = DOFLR_CODE;
+        unsigned int i;
+
+        if (rcdu->info->gen < 2)
+                return;
+
+        /*
+         * The DPAD outputs can't be controlled directly. However, the parallel
+         * output of the DU channels routed to DPAD can be set to fixed levels
+         * through the DOFLR group register. Use this to turn the DPAD on or off
+         * by driving fixed low-level signals at the output of any DU channel
+         * not routed to a DPAD output. This doesn't affect the DU output
+         * signals going to other outputs, such as the internal LVDS and HDMI
+         * encoders.
+         */
+
+        for (i = 0; i < rgrp->num_crtcs; ++i) {
+                struct rcar_du_crtc_state *rstate;
+                struct rcar_du_crtc *rcrtc;
+
+                rcrtc = &rcdu->crtcs[rgrp->index * 2 + i];
+                rstate = to_rcar_crtc_state(rcrtc->crtc.state);
+
+                if (!(rstate->outputs & dpad_mask))
+                        doflr |= doflr_values[i];
+        }
+
+        rcar_du_group_write(rgrp, DOFLR, doflr);
+}
+
 int rcar_du_group_set_routing(struct rcar_du_group *rgrp)
 {
         struct rcar_du_device *rcdu = rgrp->dev;
@@ -306,5 +347,7 @@ int rcar_du_group_set_routing(struct rcar_du_group *rgrp)
 
         rcar_du_group_write(rgrp, DORCR, dorcr);
 
+        rcar_du_group_set_dpad_levels(rgrp);
+
         return rcar_du_set_dpad0_vsp1_routing(rgrp->dev);
 }