Hi Neil,

On 11/18/2025 5:08 PM, Neil Armstrong wrote:

On 11/11/25 11:50, Chaoyi Chen wrote:

quoted

From: Chaoyi Chen <redacted>

Using the DRM_AUX_BRIDGE helper to create the transparent DRM bridge
device.

Signed-off-by: Chaoyi Chen <redacted>
---

(no changes since v7)

Changes in v6:
- Fix depend in Kconfig.

  drivers/phy/rockchip/Kconfig              |  2 +
  drivers/phy/rockchip/phy-rockchip-typec.c | 52 +++++++++++++++++++++++
  2 files changed, 54 insertions(+)

diff --git a/drivers/phy/rockchip/Kconfig b/drivers/phy/rockchip/Kconfig
index db4adc7c53da..bcb5476222fc 100644
--- a/drivers/phy/rockchip/Kconfig
+++ b/drivers/phy/rockchip/Kconfig

@@ -120,6 +120,8 @@ config PHY_ROCKCHIP_TYPEC

      tristate "Rockchip TYPEC PHY Driver"
      depends on OF && (ARCH_ROCKCHIP || COMPILE_TEST)
      depends on TYPEC || TYPEC=n
+    depends on DRM || DRM=n
+    select DRM_AUX_BRIDGE if DRM_BRIDGE
      select EXTCON
      select GENERIC_PHY
      select RESET_CONTROLLER

diff --git a/drivers/phy/rockchip/phy-rockchip-typec.c b/drivers/phy/rockchip/phy-rockchip-typec.c
index 1f5b4142cbe4..748a6eb8ad95 100644
--- a/drivers/phy/rockchip/phy-rockchip-typec.c
+++ b/drivers/phy/rockchip/phy-rockchip-typec.c

@@ -36,6 +36,7 @@

   * orientation, false is normal orientation.
   */
  +#include <linux/auxiliary_bus.h>
  #include <linux/clk.h>
  #include <linux/clk-provider.h>
  #include <linux/delay.h>

@@ -56,6 +57,7 @@

  #include <linux/phy/phy.h>
  #include <linux/usb/typec_dp.h>
  #include <linux/usb/typec_mux.h>
+#include <drm/bridge/aux-bridge.h>
    #define CMN_SSM_BANDGAP            (0x21 << 2)
  #define CMN_SSM_BIAS            (0x22 << 2)

@@ -415,6 +417,7 @@ struct rockchip_usb3phy_port_cfg {

    struct rockchip_typec_phy {
      struct device *dev;
+    struct auxiliary_device dp_port_dev;
      void __iomem *base;
      struct extcon_dev *extcon;
      struct typec_mux_dev *mux;

@@ -1299,6 +1302,51 @@ static void tcphy_typec_mux_unregister(void *data)

      typec_mux_unregister(tcphy->mux);
  }
  +static void tcphy_dp_port_dev_release(struct device *dev)
+{
+    struct auxiliary_device *adev = to_auxiliary_dev(dev);
+
+    of_node_put(adev->dev.of_node);
+}
+
+static void tcphy_dp_port_unregister_adev(void *_adev)
+{
+    struct auxiliary_device *adev = _adev;
+
+    auxiliary_device_delete(adev);
+    auxiliary_device_uninit(adev);
+}
+
+static int tcphy_aux_bridge_register(struct rockchip_typec_phy *tcphy, struct device_node *np)
+{
+    struct auxiliary_device *adev = &tcphy->dp_port_dev;
+    int ret;
+
+    adev->name = "dp_port";
+    adev->dev.parent = tcphy->dev;
+    adev->dev.of_node = of_node_get(np);
+    adev->dev.release = tcphy_dp_port_dev_release;
+
+    ret = auxiliary_device_init(adev);
+

Drop this empty line.

quoted

+    if (ret) {
+        of_node_put(adev->dev.of_node);
+        return ret;
+    }
+
+    ret = auxiliary_device_add(adev);
+    if (ret) {
+        auxiliary_device_uninit(adev);
+        return ret;
+    }
+
+    devm_add_action_or_reset(tcphy->dev, tcphy_dp_port_unregister_adev, adev);
+
+    ret = drm_aux_bridge_register(&adev->dev);

Adding an aux device to an aux device looks quite overengineered to me !

If it's a matter of using the proper of_node, you may instead create a separate
drm_aux_bridge_register() like drm_aux_bridge_register_from_node() instead.

Yes, as you said, the aux device here is only to let the drm_aux_bridge get the correct of_node. I will add the API you mentioned in v10. Thank you.


-- 
Best,
Chaoyi