drm/tegra: output: Support DRM bridges

Newer Tegra device-trees will specify a video output graph which involves
a bridge. This patch adds initial support for the DRM bridges to the Tegra
DRM output.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

diff --git a/drivers/gpu/drm/tegra/drm.h b/drivers/gpu/drm/tegra/drm.h
index b25443255be6beb1995c675fc377d0b1152f1968..f38de08e0c95194c7f19077d61c66f72cf27fd69 100644 (file)
--- a/drivers/gpu/drm/tegra/drm.h
+++ b/drivers/gpu/drm/tegra/drm.h
@@ -12,6 +12,7 @@
 #include <linux/gpio/consumer.h>
 
 #include <drm/drm_atomic.h>
+#include <drm/drm_bridge.h>
 #include <drm/drm_edid.h>
 #include <drm/drm_encoder.h>
 #include <drm/drm_fb_helper.h>
@@ -116,6 +117,7 @@ struct tegra_output {
        struct device_node *of_node;
        struct device *dev;
 
+       struct drm_bridge *bridge;
        struct drm_panel *panel;
        struct i2c_adapter *ddc;
        const struct edid *edid;

diff --git a/drivers/gpu/drm/tegra/output.c b/drivers/gpu/drm/tegra/output.c
index f050c8bac398d2a50895ed6d28b210371d2e18cd..925a9199a71068cefde67566499f67357698cb39 100644 (file)
--- a/drivers/gpu/drm/tegra/output.c
+++ b/drivers/gpu/drm/tegra/output.c
@@ -5,6 +5,7 @@
  */
 
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_of.h>
 #include <drm/drm_panel.h>
 #include <drm/drm_simple_kms_helper.h>
 
@@ -99,8 +100,19 @@ 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);
+
                output->panel = of_drm_find_panel(panel);
                of_node_put(panel);