[PATCH v5 7/7] drm/msm/dp: move of_dp_aux_populate_bus() to eDP probe()

From: Kuogee Hsieh
Date: Wed Oct 04 2023 - 12:27:49 EST


Currently eDP population is done at msm_dp_modeset_init() which happen
at binding time. Move eDP population to be done at display probe time
so that probe deferral cases can be handled effectively.
wait_for_hpd_asserted callback is added during drm_dp_aux_init()
to ensure eDP's HPD is up before proceeding eDP population.

Changes in v5:
-- inline dp_display_auxbus_population() and delete it

Changes in v4:
-- delete duplicate initialize code to dp_aux before drm_dp_aux_register()
-- delete of_get_child_by_name(dev->of_node, "aux-bus") and inline the function
-- not initialize rc = 0

Changes in v3:
-- add done_probing callback into devm_of_dp_aux_populate_bus()

Signed-off-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
---
drivers/gpu/drm/msm/dp/dp_aux.c | 34 ++++++++++++++++-----
drivers/gpu/drm/msm/dp/dp_display.c | 59 +++++++++++++++----------------------
2 files changed, 51 insertions(+), 42 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_aux.c b/drivers/gpu/drm/msm/dp/dp_aux.c
index 10b6eeb..03f4951 100644
--- a/drivers/gpu/drm/msm/dp/dp_aux.c
+++ b/drivers/gpu/drm/msm/dp/dp_aux.c
@@ -479,7 +479,6 @@ void dp_aux_deinit(struct drm_dp_aux *dp_aux)

int dp_aux_register(struct drm_dp_aux *dp_aux)
{
- struct dp_aux_private *aux;
int ret;

if (!dp_aux) {
@@ -487,12 +486,7 @@ int dp_aux_register(struct drm_dp_aux *dp_aux)
return -EINVAL;
}

- aux = container_of(dp_aux, struct dp_aux_private, dp_aux);
-
- aux->dp_aux.name = "dpu_dp_aux";
- aux->dp_aux.dev = aux->dev;
- aux->dp_aux.transfer = dp_aux_transfer;
- ret = drm_dp_aux_register(&aux->dp_aux);
+ ret = drm_dp_aux_register(dp_aux);
if (ret) {
DRM_ERROR("%s: failed to register drm aux: %d\n", __func__,
ret);
@@ -507,6 +501,21 @@ void dp_aux_unregister(struct drm_dp_aux *dp_aux)
drm_dp_aux_unregister(dp_aux);
}

+static int dp_wait_hpd_asserted(struct drm_dp_aux *dp_aux,
+ unsigned long wait_us)
+{
+ int ret;
+ struct dp_aux_private *aux;
+
+ aux = container_of(dp_aux, struct dp_aux_private, dp_aux);
+
+ pm_runtime_get_sync(aux->dev);
+ ret = dp_catalog_aux_wait_for_hpd_connect_state(aux->catalog);
+ pm_runtime_put_sync(aux->dev);
+
+ return ret;
+}
+
struct drm_dp_aux *dp_aux_get(struct device *dev, struct dp_catalog *catalog,
bool is_edp)
{
@@ -530,6 +539,17 @@ struct drm_dp_aux *dp_aux_get(struct device *dev, struct dp_catalog *catalog,
aux->catalog = catalog;
aux->retry_cnt = 0;

+ /*
+ * Use the drm_dp_aux_init() to use the aux adapter
+ * before registering AUX with the DRM device so that
+ * msm eDP panel can be detected by generic_dep_panel_probe().
+ */
+ aux->dp_aux.name = "dpu_dp_aux";
+ aux->dp_aux.dev = dev;
+ aux->dp_aux.transfer = dp_aux_transfer;
+ aux->dp_aux.wait_hpd_asserted = dp_wait_hpd_asserted;
+ drm_dp_aux_init(&aux->dp_aux);
+
return &aux->dp_aux;
}

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 79e56d9..df15145 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -1207,6 +1207,17 @@ static const struct msm_dp_desc *dp_display_get_desc(struct platform_device *pde
return NULL;
}

+static int dp_auxbus_done_probe(struct drm_dp_aux *aux)
+{
+ int rc;
+
+ rc = component_add(aux->dev, &dp_display_comp_ops);
+ if (rc)
+ DRM_ERROR("eDP component add failed, rc=%d\n", rc);
+
+ return rc;
+}
+
static int dp_display_probe(struct platform_device *pdev)
{
int rc = 0;
@@ -1272,10 +1283,18 @@ static int dp_display_probe(struct platform_device *pdev)
if (rc)
goto err;

- rc = component_add(&pdev->dev, &dp_display_comp_ops);
- if (rc) {
- DRM_ERROR("component add failed, rc=%d\n", rc);
- goto err;
+ if (dp->dp_display.is_edp) {
+ rc = devm_of_dp_aux_populate_bus(dp->aux, dp_auxbus_done_probe);
+ if (rc) {
+ DRM_ERROR("eDP auxbus population failed, rc=%d\n", rc);
+ goto err;
+ }
+ } else {
+ rc = component_add(&pdev->dev, &dp_display_comp_ops);
+ if (rc) {
+ DRM_ERROR("component add failed, rc=%d\n", rc);
+ goto err;
+ }
}

return rc;
@@ -1291,7 +1310,6 @@ static int dp_display_remove(struct platform_device *pdev)

component_del(&pdev->dev, &dp_display_comp_ops);
dp_display_deinit_sub_modules(dp);
-
platform_set_drvdata(pdev, NULL);

return 0;
@@ -1388,29 +1406,8 @@ static int dp_display_get_next_bridge(struct msm_dp *dp)
{
int rc;
struct dp_display_private *dp_priv;
- struct device_node *aux_bus;
- struct device *dev;

dp_priv = container_of(dp, struct dp_display_private, dp_display);
- dev = &dp_priv->pdev->dev;
- aux_bus = of_get_child_by_name(dev->of_node, "aux-bus");
-
- if (aux_bus && dp->is_edp) {
- /*
- * The code below assumes that the panel will finish probing
- * by the time devm_of_dp_aux_populate_ep_devices() returns.
- * This isn't a great assumption since it will fail if the
- * panel driver is probed asynchronously but is the best we
- * can do without a bigger driver reorganization.
- */
- rc = of_dp_aux_populate_bus(dp_priv->aux, NULL);
- of_node_put(aux_bus);
- if (rc)
- goto error;
- } else if (dp->is_edp) {
- DRM_ERROR("eDP aux_bus not found\n");
- return -ENODEV;
- }

/*
* External bridges are mandatory for eDP interfaces: one has to
@@ -1423,17 +1420,9 @@ static int dp_display_get_next_bridge(struct msm_dp *dp)
if (!dp->is_edp && rc == -ENODEV)
return 0;

- if (!rc) {
+ if (!rc)
dp->next_bridge = dp_priv->parser->next_bridge;
- return 0;
- }

-error:
- if (dp->is_edp) {
- of_dp_aux_depopulate_bus(dp_priv->aux);
- dp_display_host_phy_exit(dp_priv);
- dp_display_host_deinit(dp_priv);
- }
return rc;
}

--
2.7.4