Uniformly, move the next bridge attachment to the Analogix side
rather than scattered on Rockchip and Exynos sides. It can also
help get rid of the callback &analogix_dp_plat_data.attach() and
make codes more concise.

Signed-off-by: Damon Ding <damon.ding@rock-chips.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Heiko Stuebner <heiko@sntech.de> (on rk3588)

------

Changes in v6:
- Move the next bridge attachment to the Analogix side rather than
  scattered on Rockchip and Exynos sides.

Changes in v9:
- Add Tested-by tag.
---
 .../gpu/drm/bridge/analogix/analogix_dp_core.c |  7 ++++---
 drivers/gpu/drm/exynos/exynos_dp.c             | 18 ------------------
 include/drm/bridge/analogix_dp.h               |  1 -
 3 files changed, 4 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index 933f1843777f..a6c5601e16ff 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -930,10 +930,11 @@ static int analogix_dp_bridge_attach(struct drm_bridge *bridge,
 		return -EINVAL;
 	}
 
-	if (dp->plat_data->attach) {
-		ret = dp->plat_data->attach(dp->plat_data, bridge);
+	if (dp->plat_data->next_bridge) {
+		ret = drm_bridge_attach(dp->encoder, dp->plat_data->next_bridge, bridge,
+					DRM_BRIDGE_ATTACH_NO_CONNECTOR);
 		if (ret) {
-			DRM_ERROR("Failed at platform attach func\n");
+			dev_err(dp->dev, "failed to attach following panel or bridge (%d)\n", ret);
 			return ret;
 		}
 	}
diff --git a/drivers/gpu/drm/exynos/exynos_dp.c b/drivers/gpu/drm/exynos/exynos_dp.c
index 6126820aad3b..6884ea6d04eb 100644
--- a/drivers/gpu/drm/exynos/exynos_dp.c
+++ b/drivers/gpu/drm/exynos/exynos_dp.c
@@ -68,23 +68,6 @@ static int exynos_dp_poweroff(struct analogix_dp_plat_data *plat_data)
 	return exynos_dp_crtc_clock_enable(plat_data, false);
 }
 
-static int exynos_dp_bridge_attach(struct analogix_dp_plat_data *plat_data,
-				   struct drm_bridge *bridge)
-{
-	struct exynos_dp_device *dp = to_dp(plat_data);
-	int ret;
-
-	/* Pre-empt DP connector creation if there's a bridge */
-	if (plat_data->next_bridge) {
-		ret = drm_bridge_attach(&dp->encoder, plat_data->next_bridge, bridge,
-					DRM_BRIDGE_ATTACH_NO_CONNECTOR);
-		if (ret)
-			return ret;
-	}
-
-	return 0;
-}
-
 static void exynos_dp_mode_set(struct drm_encoder *encoder,
 			       struct drm_display_mode *mode,
 			       struct drm_display_mode *adjusted_mode)
@@ -195,7 +178,6 @@ static int exynos_dp_probe(struct platform_device *pdev)
 	dp->plat_data.dev_type = EXYNOS_DP;
 	dp->plat_data.power_on = exynos_dp_poweron;
 	dp->plat_data.power_off = exynos_dp_poweroff;
-	dp->plat_data.attach = exynos_dp_bridge_attach;
 	dp->plat_data.ops = &exynos_dp_ops;
 
 out:
diff --git a/include/drm/bridge/analogix_dp.h b/include/drm/bridge/analogix_dp.h
index bae969dec63a..854af692229b 100644
--- a/include/drm/bridge/analogix_dp.h
+++ b/include/drm/bridge/analogix_dp.h
@@ -34,7 +34,6 @@ struct analogix_dp_plat_data {
 
 	int (*power_on)(struct analogix_dp_plat_data *);
 	int (*power_off)(struct analogix_dp_plat_data *);
-	int (*attach)(struct analogix_dp_plat_data *, struct drm_bridge *);
 };
 
 int analogix_dp_resume(struct analogix_dp_device *dp);
-- 
2.34.1