From 2c7283721a6233999983126331e19a2aa16bd5f8 Mon Sep 17 00:00:00 2001
From: Thierry Reding <treding@nvidia.com>
Date: Mon, 20 Dec 2021 11:28:22 +0100
Subject: drm/tegra: dpaux: Populate AUX bus
Git-commit: 8913e1aea4b32a866343b14e565c62cec54f3f78
Patch-mainline: v5.17-rc6
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

The DPAUX hardware block exposes an DP AUX interface that provides
access to an AUX bus and the devices on that bus. Use the DP AUX bus
infrastructure that was recently introduced to probe devices on this
bus from DT.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/tegra/Kconfig | 1 +
 drivers/gpu/drm/tegra/dpaux.c | 7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/tegra/Kconfig b/drivers/gpu/drm/tegra/Kconfig
index 8cf5aeb9db6c..201f5175ecfe 100644
--- a/drivers/gpu/drm/tegra/Kconfig
+++ b/drivers/gpu/drm/tegra/Kconfig
@@ -5,6 +5,7 @@ config DRM_TEGRA
 	depends on COMMON_CLK
 	depends on DRM
 	depends on OF
+	select DRM_DP_AUX_BUS
 	select DRM_KMS_HELPER
 	select DRM_MIPI_DSI
 	select DRM_PANEL
diff --git a/drivers/gpu/drm/tegra/dpaux.c b/drivers/gpu/drm/tegra/dpaux.c
index 1f96e416fa08..d7a731d287d2 100644
--- a/drivers/gpu/drm/tegra/dpaux.c
+++ b/drivers/gpu/drm/tegra/dpaux.c
@@ -19,6 +19,7 @@
 #include <linux/workqueue.h>
 
 #include <drm/drm_dp_helper.h>
+#include <drm/drm_dp_aux_bus.h>
 #include <drm/drm_panel.h>
 
 #include "dp.h"
@@ -570,6 +571,12 @@ static int tegra_dpaux_probe(struct platform_device *pdev)
 	list_add_tail(&dpaux->list, &dpaux_list);
 	mutex_unlock(&dpaux_lock);
 
+	err = devm_of_dp_aux_populate_ep_devices(&dpaux->aux);
+	if (err < 0) {
+		dev_err(dpaux->dev, "failed to populate AUX bus: %d\n", err);
+		return err;
+	}
+
 	return 0;
 }
 
-- 
2.38.1