[PATCH] drm/rockchip: handle non-platform devices in rockchip_drm_endpoint_is_subdriver

[Alex Bee]

As discussed at [1] rockchip_drm_endpoint_is_subdriver will currently always
return -ENODEV for non-platform-devices (e.g. external i2c bridges), what
makes them never being considered in rockchip_rgb_init.

As suggested at [1] this additionally adds a of_device_is_available for
the node found, which will work for both platform and non-platform devices.
Also we can return early for non-platform-devices if they are enabled,
as rockchip_sub_drivers contains exclusively platform-devices.

[1] https://lore.kernel.org/all/20210316182753.GA25685@earth.li/

Suggested-by: Heiko Stuebner <heiko at sntech.de>
Signed-off-by: Alex Bee <knaerzche at gmail.com>
---
 drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
index bfba9793d238..81a5ec30ef4f 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
@@ -275,10 +275,17 @@ int rockchip_drm_endpoint_is_subdriver(struct device_node *ep)
 		return -ENODEV;
 
 	/* status disabled will prevent creation of platform-devices */
+	if (!of_device_is_available(node)) {
+		of_node_put(node);
+		return -ENODEV;
+	}
+
 	pdev = of_find_device_by_node(node);
 	of_node_put(node);
+
+	/* enabled non-platform-devices can immediately return here */
 	if (!pdev)
-		return -ENODEV;
+		return false;
 
 	/*
 	 * All rockchip subdrivers have probed at this point, so

base-commit: 6880fa6c56601bb8ed59df6c30fd390cc5f6dd8f
-- 
2.30.2