usb: typec: nb7vpq904m: switch to DRM_AUX_BRIDGE

Switch to using the new DRM_AUX_BRIDGE helper to create the
transparent DRM bridge device instead of handcoding corresponding
functionality.
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231203114333.1305826-4-dmitry.baryshkov@linaro.org

drivers/usb/typec/mux/Kconfig

@@ -40,7 +40,7 @@ config TYPEC_MUX_NB7VPQ904M
 	tristate "On Semiconductor NB7VPQ904M Type-C redriver driver"
 	depends on I2C
 	depends on DRM || DRM=n
-	select DRM_PANEL_BRIDGE if DRM
+	select DRM_AUX_BRIDGE if DRM_BRIDGE
 	select REGMAP_I2C
 	help
 	  Say Y or M if your system has a On Semiconductor NB7VPQ904M Type-C

drivers/usb/typec/mux/nb7vpq904m.c

@@ -11,7 +11,7 @@
 #include <linux/regmap.h>
 #include <linux/bitfield.h>
 #include <linux/of_graph.h>
-#include <drm/drm_bridge.h>
+#include <drm/bridge/aux-bridge.h>
 #include <linux/usb/typec_dp.h>
 #include <linux/usb/typec_mux.h>
 #include <linux/usb/typec_retimer.h>
@@ -70,8 +70,6 @@ struct nb7vpq904m {
 	bool swap_data_lanes;
 	struct typec_switch *typec_switch;
 
-	struct drm_bridge bridge;
-
 	struct mutex lock; /* protect non-concurrent retimer & switch */
 
 	enum typec_orientation orientation;
@@ -297,44 +295,6 @@ static int nb7vpq904m_retimer_set(struct typec_retimer *retimer, struct typec_re
 	return ret;
 }
 
-#if IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_DRM_PANEL_BRIDGE)
-static int nb7vpq904m_bridge_attach(struct drm_bridge *bridge,
-				    enum drm_bridge_attach_flags flags)
-{
-	struct nb7vpq904m *nb7 = container_of(bridge, struct nb7vpq904m, bridge);
-	struct drm_bridge *next_bridge;
-
-	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
-		return -EINVAL;
-
-	next_bridge = devm_drm_of_get_bridge(&nb7->client->dev, nb7->client->dev.of_node, 0, 0);
-	if (IS_ERR(next_bridge)) {
-		dev_err(&nb7->client->dev, "failed to acquire drm_bridge: %pe\n", next_bridge);
-		return PTR_ERR(next_bridge);
-	}
-
-	return drm_bridge_attach(bridge->encoder, next_bridge, bridge,
-				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
-}
-
-static const struct drm_bridge_funcs nb7vpq904m_bridge_funcs = {
-	.attach	= nb7vpq904m_bridge_attach,
-};
-
-static int nb7vpq904m_register_bridge(struct nb7vpq904m *nb7)
-{
-	nb7->bridge.funcs = &nb7vpq904m_bridge_funcs;
-	nb7->bridge.of_node = nb7->client->dev.of_node;
-
-	return devm_drm_bridge_add(&nb7->client->dev, &nb7->bridge);
-}
-#else
-static int nb7vpq904m_register_bridge(struct nb7vpq904m *nb7)
-{
-	return 0;
-}
-#endif
-
 static const struct regmap_config nb7_regmap = {
 	.max_register = 0x1f,
 	.reg_bits = 8,
@@ -461,7 +421,7 @@ static int nb7vpq904m_probe(struct i2c_client *client)
 
 	gpiod_set_value(nb7->enable_gpio, 1);
 
-	ret = nb7vpq904m_register_bridge(nb7);
+	ret = drm_aux_bridge_register(dev);
 	if (ret)
 		goto err_disable_gpio;