drm: exynos: dsi: Use child panel or bridge find helpers

commit <711c7adc4687> ("drm: exynos: dsi: Use drm panel_bridge API")
added devm_drm_of_get_bridge for looking up if child node has panel
or bridge.

However commit <b089c0a9b14c> ("Revert "drm: of: Lookup if child node
has panel or bridge") has reverted panel or bridge child node lookup
from devm_drm_of_get_bridge which eventually failed to find the DSI
devices in exynos drm dsi driver.

So, use the conventional child panel bridge lookup helpers like it
does before.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220428094808.782938-1-jagan@amarulasolutions.com

diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
index f067c86..ec67322 100644 (file)
--- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
@@ -25,6 +25,7 @@
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_bridge.h>
 #include <drm/drm_mipi_dsi.h>
+#include <drm/drm_panel.h>
 #include <drm/drm_print.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_simple_kms_helper.h>
@@ -1451,9 +1452,18 @@ static int exynos_dsi_host_attach(struct mipi_dsi_host *host,
        struct device *dev = dsi->dev;
        struct drm_encoder *encoder = &dsi->encoder;
        struct drm_device *drm = encoder->dev;
+       struct drm_panel *panel;
        int ret;
 
-       dsi->out_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0);
+       panel = of_drm_find_panel(device->dev.of_node);
+       if (!IS_ERR(panel)) {
+               dsi->out_bridge = devm_drm_panel_bridge_add(dev, panel);
+       } else {
+               dsi->out_bridge = of_drm_find_bridge(device->dev.of_node);
+               if (!dsi->out_bridge)
+                       dsi->out_bridge = ERR_PTR(-EINVAL);
+       }
+
        if (IS_ERR(dsi->out_bridge)) {
                ret = PTR_ERR(dsi->out_bridge);
                DRM_DEV_ERROR(dev, "failed to find the bridge: %d\n", ret);