From: Pin-Yen Lin <[email protected]>
ITE IT6505 can be used in systems to switch USB Type-C DisplayPort
alternate mode lane traffic between 2 Type-C ports.
Update the binding to accommodate this usage by introducing a switch
property.
Signed-off-by: Pin-Yen Lin <[email protected]>
Signed-off-by: Prashant Malani <[email protected]>
---
v5 is the first version for this patch.
.../bindings/display/bridge/ite,it6505.yaml | 97 ++++++++++++++++++-
1 file changed, 96 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
index 833d11b2303a..86bb6dc5ae6f 100644
--- a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
+++ b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
@@ -56,13 +56,46 @@ properties:
$ref: /schemas/graph.yaml#/properties/port
description: A port node pointing to DPI host port node
+ switches:
+ type: object
+ description: Set of switches controlling DisplayPort traffic on
+ outgoing RX/TX lanes to Type C ports.
+ additionalProperties: false
+
+ properties:
+ '#address-cells':
+ const: 1
+
+ '#size-cells':
+ const: 0
+
+ patternProperties:
+ '^switch@[01]$':
+ $ref: /schemas/usb/typec-switch.yaml#
+ unevaluatedProperties: false
+
+ properties:
+ reg:
+ maxItems: 1
+
+ required:
+ - reg
+
+ required:
+ - switch@0
+
required:
- compatible
- ovdd-supply
- pwr18-supply
- interrupts
- reset-gpios
- - extcon
+
+oneOf:
+ - required:
+ - extcon
+ - required:
+ - switches
additionalProperties: false
@@ -92,3 +125,65 @@ examples:
};
};
};
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+
+ i2c3 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ it6505dptx: it6505dptx@5c {
+ compatible = "ite,it6505";
+ interrupts = <8 IRQ_TYPE_LEVEL_LOW 8 0>;
+ reg = <0x5c>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&it6505_pins>;
+ ovdd-supply = <&mt6366_vsim2_reg>;
+ pwr18-supply = <&pp1800_dpbrdg_dx>;
+ reset-gpios = <&pio 177 0>;
+
+ port {
+ it6505_dp_in: endpoint {
+ remote-endpoint = <&dpi_out>;
+ };
+ };
+
+ switches {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ switch@0 {
+ compatible = "typec-switch";
+ reg = <0>;
+ mode-switch;
+
+ ports {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ port@0 {
+ reg = <0>;
+ ite_typec0: endpoint {
+ remote-endpoint = <&typec_port0>;
+ };
+ };
+ };
+ };
+
+ switch@1 {
+ compatible = "typec-switch";
+ reg = <1>;
+ mode-switch;
+
+ ports {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ port@0 {
+ reg = <0>;
+ ite_typec1: endpoint {
+ remote-endpoint = <&typec_port1>;
+ };
+ };
+ };
+ };
+ };
+ };
+ };
--
2.37.0.rc0.104.g0611611a94-goog
Quoting Prashant Malani (2022-06-22 10:34:35)
> From: Pin-Yen Lin <[email protected]>
>
> ITE IT6505 can be used in systems to switch USB Type-C DisplayPort
> alternate mode lane traffic between 2 Type-C ports.
How does it work? From what I can tell from the information I find when
googling this part[1] and looking at the existing binding doc is that
this device is a DPI to DP bridge, and it outputs DP (probably 4 lanes
of it?). Does the 2 type-c port design work by transmitting DP on two
lanes of DP for one type-c port and another two lanes of DP for the
other type-c port?
DP could be one lane, so if this device is able to output one lane on
any output differential pair then I suspect it could support 4 type-c
ports if the hardware engineer connected it that way. Can you confirm my
suspicion?
[1] https://www.ite.com.tw/en/product/view?mid=45
Quoting Prashant Malani (2022-06-23 11:37:08)
> On Thu, Jun 23, 2022 at 11:24 AM Stephen Boyd <[email protected]> wrote:
> >
> > Quoting Prashant Malani (2022-06-22 10:34:35)
> > > From: Pin-Yen Lin <[email protected]>
> > >
> > > ITE IT6505 can be used in systems to switch USB Type-C DisplayPort
> > > alternate mode lane traffic between 2 Type-C ports.
> >
> > How does it work? From what I can tell from the information I find when
> > googling this part[1] and looking at the existing binding doc is that
> > this device is a DPI to DP bridge, and it outputs DP (probably 4 lanes
> > of it?). Does the 2 type-c port design work by transmitting DP on two
> > lanes of DP for one type-c port and another two lanes of DP for the
> > other type-c port?
> >
> > DP could be one lane, so if this device is able to output one lane on
> > any output differential pair then I suspect it could support 4 type-c
> > ports if the hardware engineer connected it that way. Can you confirm my
> > suspicion?
>
> I will let Pin-Yen comment re: this hardware, but 1-lane DP is not a
> supported Type-C Pin assignment
> (as per VESA DP Alternate Mode Spec version 2.0 [2]), so the H/W
Some missing link?
> configuration you are suggesting shouldn't be possible.
>
Alright, cool. But it is possible in the DP spec. So it seems like if
this is connected to 4 DP connectors it could be used to mux between DP
on 4 DP ports.
On Thu, Jun 23, 2022 at 11:24 AM Stephen Boyd <[email protected]> wrote:
>
> Quoting Prashant Malani (2022-06-22 10:34:35)
> > From: Pin-Yen Lin <[email protected]>
> >
> > ITE IT6505 can be used in systems to switch USB Type-C DisplayPort
> > alternate mode lane traffic between 2 Type-C ports.
>
> How does it work? From what I can tell from the information I find when
> googling this part[1] and looking at the existing binding doc is that
> this device is a DPI to DP bridge, and it outputs DP (probably 4 lanes
> of it?). Does the 2 type-c port design work by transmitting DP on two
> lanes of DP for one type-c port and another two lanes of DP for the
> other type-c port?
>
> DP could be one lane, so if this device is able to output one lane on
> any output differential pair then I suspect it could support 4 type-c
> ports if the hardware engineer connected it that way. Can you confirm my
> suspicion?
I will let Pin-Yen comment re: this hardware, but 1-lane DP is not a
supported Type-C Pin assignment
(as per VESA DP Alternate Mode Spec version 2.0 [2]), so the H/W
configuration you are suggesting shouldn't be possible.
>
> [1] https://www.ite.com.tw/en/product/view?mid=45
On Thu, Jun 23, 2022 at 12:08 PM Stephen Boyd <[email protected]> wrote:
>
> Quoting Prashant Malani (2022-06-23 11:37:08)
> > On Thu, Jun 23, 2022 at 11:24 AM Stephen Boyd <[email protected]> wrote:
> > >
> > > Quoting Prashant Malani (2022-06-22 10:34:35)
> > > > From: Pin-Yen Lin <[email protected]>
> > > >
> > > > ITE IT6505 can be used in systems to switch USB Type-C DisplayPort
> > > > alternate mode lane traffic between 2 Type-C ports.
> > >
> > > How does it work? From what I can tell from the information I find when
> > > googling this part[1] and looking at the existing binding doc is that
> > > this device is a DPI to DP bridge, and it outputs DP (probably 4 lanes
> > > of it?). Does the 2 type-c port design work by transmitting DP on two
> > > lanes of DP for one type-c port and another two lanes of DP for the
> > > other type-c port?
> > >
> > > DP could be one lane, so if this device is able to output one lane on
> > > any output differential pair then I suspect it could support 4 type-c
> > > ports if the hardware engineer connected it that way. Can you confirm my
> > > suspicion?
> >
> > I will let Pin-Yen comment re: this hardware, but 1-lane DP is not a
> > supported Type-C Pin assignment
> > (as per VESA DP Alternate Mode Spec version 2.0 [2]), so the H/W
>
> Some missing link?
My bad. I tried to find a publicly accessible link to the DP altmode
spec, but it
seems like one needs to be a VESA member to access it :/
>
> > configuration you are suggesting shouldn't be possible.
> >
>
> Alright, cool. But it is possible in the DP spec. So it seems like if
> this is connected to 4 DP connectors it could be used to mux between DP
> on 4 DP ports.
Ack. In that case, no "typec-switches" should be added to the DT.