[PATCH v5 07/11] drm/tegra: Make panel parsing by tegra_output_probe() optional

From: Svyatoslav Ryhel

Date: Thu Oct 29 2026 - 11:34:17 EST


The tegra_output_probe() performs panel parsing unconditionally, even for
devices that do not require it (such as HDMI) or that handle panel parsing
on their own (like DSI). Make panel parsing configurable.

Signed-off-by: Svyatoslav Ryhel <clamor95@xxxxxxxxx>
---
drivers/gpu/drm/tegra/drm.h | 2 +-
drivers/gpu/drm/tegra/dsi.c | 2 +-
drivers/gpu/drm/tegra/hdmi.c | 2 +-
drivers/gpu/drm/tegra/output.c | 52 ++++++++++++++++++----------------
drivers/gpu/drm/tegra/rgb.c | 2 +-
drivers/gpu/drm/tegra/sor.c | 2 +-
6 files changed, 32 insertions(+), 30 deletions(-)

diff --git a/drivers/gpu/drm/tegra/drm.h b/drivers/gpu/drm/tegra/drm.h
index bc720ae8d95e1..e53fe68161cb8 100644
--- a/drivers/gpu/drm/tegra/drm.h
+++ b/drivers/gpu/drm/tegra/drm.h
@@ -156,7 +156,7 @@ static inline struct tegra_output *connector_to_output(struct drm_connector *c)
}

/* from output.c */
-int tegra_output_probe(struct tegra_output *output);
+int tegra_output_probe(struct tegra_output *output, bool get_panel);
void tegra_output_remove(struct tegra_output *output);
int tegra_output_init(struct drm_device *drm, struct tegra_output *output);
void tegra_output_exit(struct tegra_output *output);
diff --git a/drivers/gpu/drm/tegra/dsi.c b/drivers/gpu/drm/tegra/dsi.c
index 7b595310e7379..a4c0c63bbe567 100644
--- a/drivers/gpu/drm/tegra/dsi.c
+++ b/drivers/gpu/drm/tegra/dsi.c
@@ -1618,7 +1618,7 @@ static int tegra_dsi_probe(struct platform_device *pdev)
if (err < 0)
return err;

- err = tegra_output_probe(&dsi->output);
+ err = tegra_output_probe(&dsi->output, false);
if (err < 0)
return err;

diff --git a/drivers/gpu/drm/tegra/hdmi.c b/drivers/gpu/drm/tegra/hdmi.c
index 0d2c0ab0a63e9..c0845bb45bb15 100644
--- a/drivers/gpu/drm/tegra/hdmi.c
+++ b/drivers/gpu/drm/tegra/hdmi.c
@@ -1855,7 +1855,7 @@ static int tegra_hdmi_probe(struct platform_device *pdev)

hdmi->output.dev = &pdev->dev;

- err = tegra_output_probe(&hdmi->output);
+ err = tegra_output_probe(&hdmi->output, false);
if (err < 0)
return err;

diff --git a/drivers/gpu/drm/tegra/output.c b/drivers/gpu/drm/tegra/output.c
index d0ba3bd0aab8f..ff2e28a1e00b7 100644
--- a/drivers/gpu/drm/tegra/output.c
+++ b/drivers/gpu/drm/tegra/output.c
@@ -94,7 +94,7 @@ static irqreturn_t hpd_irq(int irq, void *data)
return IRQ_HANDLED;
}

-int tegra_output_probe(struct tegra_output *output)
+int tegra_output_probe(struct tegra_output *output, bool get_panel)
{
struct device_node *ddc, *panel;
const void *edid;
@@ -104,31 +104,33 @@ int tegra_output_probe(struct tegra_output *output)
if (!output->of_node)
output->of_node = output->dev->of_node;

- err = drm_of_find_panel_or_bridge(output->of_node, -1, -1,
- &output->panel, &output->bridge);
- if (err && err != -ENODEV)
- return err;
-
- panel = of_parse_phandle(output->of_node, "nvidia,panel", 0);
- if (panel) {
- /*
- * Don't mix nvidia,panel phandle with the graph in a
- * device-tree.
- */
- WARN_ON(output->panel || output->bridge);
-
- if (output->panel) {
- drm_panel_put(output->panel);
- output->panel = NULL;
- }
-
- output->panel = of_drm_find_panel(panel);
- of_node_put(panel);
-
- if (IS_ERR(output->panel)) {
- err = PTR_ERR(output->panel);
- output->panel = NULL;
+ if (get_panel) {
+ err = drm_of_find_panel_or_bridge(output->of_node, -1, -1,
+ &output->panel, &output->bridge);
+ if (err && err != -ENODEV)
return err;
+
+ panel = of_parse_phandle(output->of_node, "nvidia,panel", 0);
+ if (panel) {
+ /*
+ * Don't mix nvidia,panel phandle with the graph in a
+ * device-tree.
+ */
+ WARN_ON(output->panel || output->bridge);
+
+ if (output->panel) {
+ drm_panel_put(output->panel);
+ output->panel = NULL;
+ }
+
+ output->panel = of_drm_find_panel(panel);
+ of_node_put(panel);
+
+ if (IS_ERR(output->panel)) {
+ err = PTR_ERR(output->panel);
+ output->panel = NULL;
+ return err;
+ }
}
}

diff --git a/drivers/gpu/drm/tegra/rgb.c b/drivers/gpu/drm/tegra/rgb.c
index addcecf8592b1..01475995d9cc8 100644
--- a/drivers/gpu/drm/tegra/rgb.c
+++ b/drivers/gpu/drm/tegra/rgb.c
@@ -236,7 +236,7 @@ int tegra_dc_rgb_probe(struct tegra_dc *dc)
rgb->output.of_node = np;
rgb->dc = dc;

- err = tegra_output_probe(&rgb->output);
+ err = tegra_output_probe(&rgb->output, true);
if (err < 0)
return err;

diff --git a/drivers/gpu/drm/tegra/sor.c b/drivers/gpu/drm/tegra/sor.c
index e384cbd0cbf72..ab81e412e05f1 100644
--- a/drivers/gpu/drm/tegra/sor.c
+++ b/drivers/gpu/drm/tegra/sor.c
@@ -3806,7 +3806,7 @@ static int tegra_sor_probe(struct platform_device *pdev)
if (err < 0)
goto put_aux;

- err = tegra_output_probe(&sor->output);
+ err = tegra_output_probe(&sor->output, true);
if (err < 0) {
dev_err_probe(&pdev->dev, err, "failed to probe output\n");
goto put_aux;
--
2.53.0