Apple's Type-C PHY (ATCPHY) is a PHY for USB 2.0, USB 3.x,
USB4/Thunderbolt, and DisplayPort connectivity found in Apple Silicon
SoCs.
The PHY handles muxing between these different protocols and also provides
the reset controller for the attached dwc3 USB controller.
Signed-off-by: Sven Peter <sven@kernel.org>
---
.../devicetree/bindings/phy/apple,atcphy.yaml | 213 +++++++++++++++++++++
MAINTAINERS | 1 +
2 files changed, 214 insertions(+)
diff --git a/Documentation/devicetree/bindings/phy/apple,atcphy.yaml b/Documentation/devicetree/bindings/phy/apple,atcphy.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..a863fe3a8f6d80a113e495e8425775c91e4cd10c
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/apple,atcphy.yaml
@@ -0,0 +1,213 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/apple,atcphy.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Apple Type-C PHY (ATCPHY)
+
+maintainers:
+ - Sven Peter <sven@kernel.org>
+
+description:
+ The Apple Type-C PHY (ATCPHY) is a PHY for USB 2.0, USB 3.x,
+ USB4/Thunderbolt, and DisplayPort connectivity found in Apple Silicon SoCs.
+
+ The PHY handles muxing between these different protocols and also provides the
+ reset controller for the attached DWC3 USB controller.
+
+ The PHY is designed for USB4 operation and does not handle individual
+ differential pairs as distinct DisplayPort lanes. Any reference to lane in
+ this binding hence refers to two differential pairs (RX and TX) as used in USB
+ terminology.
+
+allOf:
+ - $ref: /schemas/usb/usb-switch.yaml#
+
+properties:
+ compatible:
+ oneOf:
+ - items:
+ - enum:
+ - apple,t6000-atcphy
+ - apple,t6020-atcphy
+ - apple,t8112-atcphy
+ - const: apple,t8103-atcphy
+ - const: apple,t8103-atcphy
+
+ reg:
+ items:
+ - description: Common controls for all PHYs (USB2/3/4, DisplayPort, Thunderbolt)
+ - description: DisplayPort Alternate Mode PHY specific controls
+ - description: AXI to Apple Fabric interconnect controls, only modified by tunables
+ - description: USB2 PHY specific controls
+ - description: USB3 PIPE interface controls
+
+ reg-names:
+ items:
+ - const: core
+ - const: lpdptx
+ - const: axi2af
+ - const: usb2phy
+ - const: pipehandler
+
+ "#phy-cells":
+ const: 1
+
+ "#reset-cells":
+ const: 0
+
+ mode-switch: true
+ orientation-switch: true
+
+ power-domains:
+ maxItems: 1
+
+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: Output endpoint of the PHY to the Type-C connector
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: Incoming endpoint from the USB3 controller
+
+ port@2:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: Incoming endpoint from the DisplayPort controller
+
+ port@3:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: Incoming endpoint from the USB4/Thunderbolt controller
+
+ apple,tunable-axi2af:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description:
+ AXI2AF tunables.
+
+ This array is filled with 3-tuples each containing three 32-bit values
+ <register offset>, <mask>, and <value> by the bootloader.
+ The driver will use these to configure the PHY by reading from each
+ register, ANDing it with <mask>, ORing it with <value>, and storing the
+ result back to the register.
+ These values slightly differ even between different chips of the same
+ generation and are likely calibration values determined by Apple at
+ manufacturing time.
+
+ apple,tunable-common:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description:
+ Common tunables required for all modes, see apple,tunable-axi2af for details.
+
+ apple,tunable-fuses:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description:
+ Fuse based tunables required for all modes, see apple,tunable-axi2af for details.
+
+ apple,tunable-lane0-usb:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description:
+ USB tunables on lane 0, see apple,tunable-axi2af for details.
+
+ apple,tunable-lane1-usb:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description:
+ USB tunables on lane 1, see apple,tunable-axi2af for details.
+
+ apple,tunable-lane0-cio:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description:
+ USB4/Thunderbolt ("converged IO") tunables on lane 0, see apple,tunable-axi2af for details.
+
+ apple,tunable-lane1-cio:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description:
+ USB4/Thunderbolt ("converged IO") tunables on lane 1, see apple,tunable-axi2af for details.
+
+ apple,tunable-lane0-dp:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description:
+ DisplayPort tunables on lane 0, see apple,tunable-axi2af for details.
+
+ Note that lane here refers to a USB RX and TX pair re-used for DisplayPort
+ and not to an individual DisplayPort differential lane.
+
+ apple,tunable-lane1-dp:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description:
+ DisplayPort tunables on lane 1, see apple,tunable-axi2af for details.
+
+ Note that lane here refers to a USB RX and TX pair re-used for DisplayPort
+ and not to an individual DisplayPort differential lane.
+
+required:
+ - compatible
+ - reg
+ - reg-names
+ - "#phy-cells"
+ - "#reset-cells"
+ - orientation-switch
+ - mode-switch
+ - power-domains
+ - ports
+
+additionalProperties: false
+
+examples:
+ - |
+ phy@83000000 {
+ compatible = "apple,t8103-atcphy";
+ reg = <0x83000000 0x4c000>,
+ <0x83050000 0x8000>,
+ <0x80000000 0x4000>,
+ <0x82a90000 0x4000>,
+ <0x82a84000 0x4000>;
+ reg-names = "core", "lpdptx", "axi2af", "usb2phy",
+ "pipehandler";
+
+ #phy-cells = <1>;
+ #reset-cells = <0>;
+
+ orientation-switch;
+ mode-switch;
+ power-domains = <&ps_atc0_usb>;
+
+ ports {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ port@0 {
+ reg = <0>;
+
+ endpoint {
+ remote-endpoint = <&typec_connector_ss>;
+ };
+ };
+
+ port@1 {
+ reg = <1>;
+
+ endpoint {
+ remote-endpoint = <&dwc3_ss_out>;
+ };
+ };
+
+ port@2 {
+ reg = <2>;
+
+ endpoint {
+ remote-endpoint = <&dcp_dp_out>;
+ };
+ };
+
+ port@3 {
+ reg = <3>;
+
+ endpoint {
+ remote-endpoint = <&acio_tbt_out>;
+ };
+ };
+ };
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index e147e1b919d5737a34e684ec587872ce591c641a..c4cbae63b0c0d42042e12d366e4a32d7ca3711ea 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2393,6 +2393,7 @@ F: Documentation/devicetree/bindings/nvme/apple,nvme-ans.yaml
F: Documentation/devicetree/bindings/nvmem/apple,efuses.yaml
F: Documentation/devicetree/bindings/nvmem/apple,spmi-nvmem.yaml
F: Documentation/devicetree/bindings/pci/apple,pcie.yaml
+F: Documentation/devicetree/bindings/phy/apple,atcphy.yaml
F: Documentation/devicetree/bindings/pinctrl/apple,pinctrl.yaml
F: Documentation/devicetree/bindings/power/apple*
F: Documentation/devicetree/bindings/power/reset/apple,smc-reboot.yaml
--
2.34.1On Sat, Sep 06, 2025 at 03:43:29PM +0000, Sven Peter wrote:
> Apple's Type-C PHY (ATCPHY) is a PHY for USB 2.0, USB 3.x,
> USB4/Thunderbolt, and DisplayPort connectivity found in Apple Silicon
> SoCs.
>
> The PHY handles muxing between these different protocols and also provides
> the reset controller for the attached dwc3 USB controller.
>
> Signed-off-by: Sven Peter <sven@kernel.org>
> ---
> .../devicetree/bindings/phy/apple,atcphy.yaml | 213 +++++++++++++++++++++
> MAINTAINERS | 1 +
> 2 files changed, 214 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/phy/apple,atcphy.yaml b/Documentation/devicetree/bindings/phy/apple,atcphy.yaml
> new file mode 100644
> index 0000000000000000000000000000000000000000..a863fe3a8f6d80a113e495e8425775c91e4cd10c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/phy/apple,atcphy.yaml
> @@ -0,0 +1,213 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/phy/apple,atcphy.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Apple Type-C PHY (ATCPHY)
> +
> +maintainers:
> + - Sven Peter <sven@kernel.org>
> +
> +description:
Add '>' to to maintain paragraph formatting.
> + The Apple Type-C PHY (ATCPHY) is a PHY for USB 2.0, USB 3.x,
> + USB4/Thunderbolt, and DisplayPort connectivity found in Apple Silicon SoCs.
> +
> + The PHY handles muxing between these different protocols and also provides the
> + reset controller for the attached DWC3 USB controller.
> +
> + The PHY is designed for USB4 operation and does not handle individual
> + differential pairs as distinct DisplayPort lanes. Any reference to lane in
> + this binding hence refers to two differential pairs (RX and TX) as used in USB
> + terminology.
> +
> +allOf:
> + - $ref: /schemas/usb/usb-switch.yaml#
> +
> +properties:
> + compatible:
> + oneOf:
> + - items:
> + - enum:
> + - apple,t6000-atcphy
> + - apple,t6020-atcphy
> + - apple,t8112-atcphy
> + - const: apple,t8103-atcphy
> + - const: apple,t8103-atcphy
> +
> + reg:
> + items:
> + - description: Common controls for all PHYs (USB2/3/4, DisplayPort, Thunderbolt)
> + - description: DisplayPort Alternate Mode PHY specific controls
> + - description: AXI to Apple Fabric interconnect controls, only modified by tunables
> + - description: USB2 PHY specific controls
> + - description: USB3 PIPE interface controls
> +
> + reg-names:
> + items:
> + - const: core
> + - const: lpdptx
> + - const: axi2af
> + - const: usb2phy
> + - const: pipehandler
> +
> + "#phy-cells":
> + const: 1
> +
> + "#reset-cells":
> + const: 0
> +
> + mode-switch: true
> + orientation-switch: true
> +
> + power-domains:
> + maxItems: 1
> +
> + ports:
> + $ref: /schemas/graph.yaml#/properties/ports
> + properties:
> + port@0:
> + $ref: /schemas/graph.yaml#/properties/port
> + description: Output endpoint of the PHY to the Type-C connector
SS port of the connector?
> +
> + port@1:
> + $ref: /schemas/graph.yaml#/properties/port
> + description: Incoming endpoint from the USB3 controller
> +
> + port@2:
> + $ref: /schemas/graph.yaml#/properties/port
> + description: Incoming endpoint from the DisplayPort controller
> +
> + port@3:
> + $ref: /schemas/graph.yaml#/properties/port
> + description: Incoming endpoint from the USB4/Thunderbolt controller
> +
> + apple,tunable-axi2af:
> + $ref: /schemas/types.yaml#/definitions/uint32-array
> + description:
> + AXI2AF tunables.
> +
> + This array is filled with 3-tuples each containing three 32-bit values
> + <register offset>, <mask>, and <value> by the bootloader.
That sounds like a 3xN matrix. Use uint32-matrix type.
blank line between paragraphs and use '>' modifier.
> + The driver will use these to configure the PHY by reading from each
> + register, ANDing it with <mask>, ORing it with <value>, and storing the
> + result back to the register.
> + These values slightly differ even between different chips of the same
> + generation and are likely calibration values determined by Apple at
> + manufacturing time.
This could be worded more simply. The first part sounds like fixed for a
given SoC, but from manufacturing time setting I gather these vary even
for a single product/device.
I gather all this is being copied out of Apple FW?
> +
> + apple,tunable-common:
> + $ref: /schemas/types.yaml#/definitions/uint32-array
> + description:
> + Common tunables required for all modes, see apple,tunable-axi2af for details.
> +
> + apple,tunable-fuses:
> + $ref: /schemas/types.yaml#/definitions/uint32-array
> + description:
> + Fuse based tunables required for all modes, see apple,tunable-axi2af for details.
> +
> + apple,tunable-lane0-usb:
> + $ref: /schemas/types.yaml#/definitions/uint32-array
> + description:
> + USB tunables on lane 0, see apple,tunable-axi2af for details.
> +
> + apple,tunable-lane1-usb:
> + $ref: /schemas/types.yaml#/definitions/uint32-array
> + description:
> + USB tunables on lane 1, see apple,tunable-axi2af for details.
> +
> + apple,tunable-lane0-cio:
> + $ref: /schemas/types.yaml#/definitions/uint32-array
> + description:
> + USB4/Thunderbolt ("converged IO") tunables on lane 0, see apple,tunable-axi2af for details.
Wrap lines at 80 char.
> +
> + apple,tunable-lane1-cio:
> + $ref: /schemas/types.yaml#/definitions/uint32-array
> + description:
> + USB4/Thunderbolt ("converged IO") tunables on lane 1, see apple,tunable-axi2af for details.
> +
> + apple,tunable-lane0-dp:
> + $ref: /schemas/types.yaml#/definitions/uint32-array
> + description:
> + DisplayPort tunables on lane 0, see apple,tunable-axi2af for details.
> +
> + Note that lane here refers to a USB RX and TX pair re-used for DisplayPort
> + and not to an individual DisplayPort differential lane.
> +
> + apple,tunable-lane1-dp:
> + $ref: /schemas/types.yaml#/definitions/uint32-array
> + description:
> + DisplayPort tunables on lane 1, see apple,tunable-axi2af for details.
> +
> + Note that lane here refers to a USB RX and TX pair re-used for DisplayPort
> + and not to an individual DisplayPort differential lane.
> +
> +required:
> + - compatible
> + - reg
> + - reg-names
> + - "#phy-cells"
> + - "#reset-cells"
> + - orientation-switch
> + - mode-switch
> + - power-domains
> + - ports
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + phy@83000000 {
> + compatible = "apple,t8103-atcphy";
> + reg = <0x83000000 0x4c000>,
> + <0x83050000 0x8000>,
> + <0x80000000 0x4000>,
> + <0x82a90000 0x4000>,
> + <0x82a84000 0x4000>;
> + reg-names = "core", "lpdptx", "axi2af", "usb2phy",
> + "pipehandler";
> +
> + #phy-cells = <1>;
> + #reset-cells = <0>;
> +
> + orientation-switch;
> + mode-switch;
> + power-domains = <&ps_atc0_usb>;
> +
> + ports {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + port@0 {
> + reg = <0>;
> +
> + endpoint {
> + remote-endpoint = <&typec_connector_ss>;
> + };
> + };
> +
> + port@1 {
> + reg = <1>;
> +
> + endpoint {
> + remote-endpoint = <&dwc3_ss_out>;
> + };
> + };
> +
> + port@2 {
> + reg = <2>;
> +
> + endpoint {
> + remote-endpoint = <&dcp_dp_out>;
> + };
> + };
> +
> + port@3 {
> + reg = <3>;
> +
> + endpoint {
> + remote-endpoint = <&acio_tbt_out>;
> + };
> + };
> + };
> + };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e147e1b919d5737a34e684ec587872ce591c641a..c4cbae63b0c0d42042e12d366e4a32d7ca3711ea 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -2393,6 +2393,7 @@ F: Documentation/devicetree/bindings/nvme/apple,nvme-ans.yaml
> F: Documentation/devicetree/bindings/nvmem/apple,efuses.yaml
> F: Documentation/devicetree/bindings/nvmem/apple,spmi-nvmem.yaml
> F: Documentation/devicetree/bindings/pci/apple,pcie.yaml
> +F: Documentation/devicetree/bindings/phy/apple,atcphy.yaml
> F: Documentation/devicetree/bindings/pinctrl/apple,pinctrl.yaml
> F: Documentation/devicetree/bindings/power/apple*
> F: Documentation/devicetree/bindings/power/reset/apple,smc-reboot.yaml
>
> --
> 2.34.1
>
>
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