On Tue, Mar 30, 2021 at 05:14:44PM +0200, Enric Balletbo i Serra wrote: > On 30/3/21 15:35, Dafna Hirschfeld wrote: > > On 05.03.21 16:19, Laurent Pinchart wrote: > >> On Fri, Mar 05, 2021 at 04:14:03PM +0100, Dafna Hirschfeld wrote: > >>> On 05.03.21 15:34, Laurent Pinchart wrote: > >>>> On Fri, Mar 05, 2021 at 01:43:50PM +0100, Dafna Hirschfeld wrote: > >>>>> ANX7688 is a USB Type-C port controller with a MUX. It converts HDMI 2.0 to > >>>>> DisplayPort 1.3 Ultra-HDi (4096x2160p60). > >>>>> The integrated crosspoint switch (the MUX) supports USB 3.1 data transfer > >>>>> along with the DisplayPort Alternate Mode signaling over USB Type-C. > >>>>> Additionally, an on-chip microcontroller (OCM) is available to manage the > >>>>> signal switching, Channel Configuration (CC) detection, USB Power > >>>>> Delivery (USB-PD), Vendor Defined Message (VDM) protocol support and other > >>>>> functions as defined in the USB TypeC and USB Power Delivery > >>>>> specifications. > >>>>> > >>>>> ANX7688 is found on Acer Chromebook R13 (elm) and on > >>>>> Pine64 PinePhone. > >>>>> > >>>>> Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@xxxxxxxxxxxxx> > >>>>> --- > >>>>> .../bindings/usb/analogix,anx7688.yaml | 177 ++++++++++++++++++ > >>>>> 1 file changed, 177 insertions(+) > >>>>> create mode 100644 > >>>>> Documentation/devicetree/bindings/usb/analogix,anx7688.yaml > >>>>> > >>>>> diff --git a/Documentation/devicetree/bindings/usb/analogix,anx7688.yaml > >>>>> b/Documentation/devicetree/bindings/usb/analogix,anx7688.yaml > >>>>> new file mode 100644 > >>>>> index 000000000000..6c4dd6b4b28b > >>>>> --- /dev/null > >>>>> +++ b/Documentation/devicetree/bindings/usb/analogix,anx7688.yaml > >>>>> @@ -0,0 +1,177 @@ > >>>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > >>>>> +%YAML 1.2 > >>>>> +--- > >>>>> +$id: http://devicetree.org/schemas/usb/analogix,anx7688.yaml# > >>>>> +$schema: http://devicetree.org/meta-schemas/core.yaml# > >>>>> + > >>>>> +title: Analogix ANX7688 Type-C Port Controller with HDMI to DP conversion > >>>>> + > >>>>> +maintainers: > >>>>> + - Nicolas Boichat <drinkcat@xxxxxxxxxxxx> > >>>>> + - Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx> > >>>>> + > >>>>> +description: | > >>>>> + ANX7688 is a USB Type-C port controller with a MUX. It converts HDMI 2.0 to > >>>>> + DisplayPort 1.3 Ultra-HDi (4096x2160p60). > >>>>> + The integrated crosspoint switch (the MUX) supports USB 3.1 data > >>>>> transfer along with > >>>>> + the DisplayPort Alternate Mode signaling over USB Type-C. Additionally, > >>>>> + an on-chip microcontroller (OCM) is available to manage the signal > >>>>> switching, > >>>>> + Channel Configuration (CC) detection, USB Power Delivery (USB-PD), Vendor > >>>>> + Defined Message (VDM) protocol support and other functions as defined in > >>>>> the > >>>>> + USB TypeC and USB Power Delivery specifications. > >>>>> + > >>>>> + > >>>> > >>>> Extra blank line ? > >>>> > >>>>> +properties: > >>>>> + compatible: > >>>>> + const: analogix,anx7688 > >>>>> + > >>>>> + reg: > >>>>> + maxItems: 1 > >>>>> + > >>>>> + avdd33-supply: > >>>>> + description: 3.3V Analog core supply voltage. > >>>>> + > >>>>> + dvdd18-supply: > >>>>> + description: 1.8V Digital I/O supply voltage. > >>>>> + > >>>>> + avdd18-supply: > >>>>> + description: 1.8V Analog core power supply voltage. > >>>>> + > >>>>> + avdd10-supply: > >>>>> + description: 1.0V Analog core power supply voltage. > >>>>> + > >>>>> + dvdd10-supply: > >>>>> + description: 1.0V Digital core supply voltage. > >>>>> + > >>>> > >>>> That's lots of supplies. If there's a reasonable chance that some of > >>>> them will always be driven by the same regulator (especially if the > >>>> ANX7688 documentation requires that), then they could be grouped. For > >>>> instance dvdd18-supply and avdd18-supply could be grouped into > >>>> vdd18-supply. It would still allow us to extend the bindings in a > >>>> backward compatible way later if a system uses different regulators. You > >>>> have more information about the hardware than I do, so it's your call. > > > > Can you explain what do you mean by 'grouped' ? > > Do you mean that instead of having two properties dvdd18-supply and avdd18-supply > > I have only one property vdd18-supply? > > You can simplify all this with vdd33, vdd18 vdd10. For the Chromebook case all > the analogic and digital part are the same regulator just filtered. That's a > common configuration and if there is some hardware that needs it we can extend > later. That's the idea, yes. If in a typical use case multiple supplies are provided by a single regulator (for some devices that datasheet strongly recommends that, or event mandates it), then it makes sense to group those supplies in a single DT supply property. It can always be extended later indeed, without any backward compatibility issue. > >>>>> + hdmi5v-supply: > >>>>> + description: 5V power supply for the HDMI. > >>>>> + > >>>>> + hdmi_vt-supply: > >>>>> + description: Termination voltage for HDMI input. > >>>> > >>>> Maybe hdmi-vt-supply ? > >>>> > >>>>> + > >>>>> + clocks: > >>>>> + description: The input clock specifier. > >>>>> + maxItems: 1 > >>>> > >>>> How about > >>>> > >>>> items: > >>>> - description: The input clock specifier. > >>>> > >>>>> + > >>>>> + clock-names: > >>>>> + items: > >>>>> + - const: xtal > >>>>> + > >>>>> + hpd-gpios: > >>>>> + description: | > >>>>> + In USB Type-C applications, DP_HPD has no use. In standard DisplayPort > >>>>> + applications, DP_HPD is used as DP hot-plug. > >>>>> + maxItems: 1 > >>>>> + > >>>>> + enable-gpios: > >>>>> + description: Chip power down control. No internal pull-down or pull-up > >>>>> resistor. > >>>>> + maxItems: 1 > >>>>> + > >>>>> + reset-gpios: > >>>>> + description: Reset input signal. Active low. > >>>>> + maxItems: 1 > >>>>> + > >>>>> + vbus-det-gpios: > >>>>> + description: | > >>>>> + An input gpio for VBUS detection and high voltage detection, > >>>>> + external resistance divide VBUS voltage to 1/8. > >>>>> + maxItems: 1 > >>>>> + > >>>>> + interrupts: > >>>>> + description: | > >>>>> + The interrupt notifies 4 possible events - TCPC ALERT int, PD int, > >>>>> DP int, HDMI int. > >>>>> + maxItems: 1 > >>>>> + > >>>>> + cabledet-gpios: > >>>>> + description: An output gpio, indicates by the device that a cable is > >>>>> plugged. > >>>>> + maxItems: 1 > >>>>> + > >>>>> + vbus-ctrl-gpios: > >>>>> + description: > >>>>> + External VBUS power path. Enable VBUS source and disable VBUS sink > >>>>> or vice versa. > >>>>> + maxItems: 1 > >>>>> + > >>>>> + vconn-en1-gpios: > >>>>> + description: Controls the VCONN switch on the CC1 pin. > >>>>> + maxItems: 1 > >>>>> + > >>>>> + vconn-en2-gpios: > >>>>> + description: Controls the VCONN switch on the CC2 pin. > >>>>> + maxItems: 1 > >>>>> + > >>>>> + ports: > >>>>> + $ref: /schemas/graph.yaml#/properties/ports > >>>>> + > >>>>> + properties: > >>>>> + port@0: > >>>>> + $ref: /schemas/graph.yaml#/properties/port > >>>>> + description: Video port for HDMI input. > >>>>> + > >>>>> + port@1: > >>>>> + $ref: /schemas/graph.yaml#/properties/port > >>>>> + description: USB port for the USB3 input. > >>>>> + > >>>>> + port@2: > >>>>> + $ref: /schemas/graph.yaml#/properties/port > >>>>> + description: USB Type-c connector, see connector/usb-connector.yaml. > >>>>> + > >>>>> + required: > >>>>> + - port@0 > >>>> > >>>> As all the ports exist at the hardware level, should they always be > >>>> present ? The endpoints are optional of course, in case a port isn't > >>>> connected on a particular system. > >>>> > >>>>> + > >>>>> +required: > >>>>> + - compatible > >>>>> + - reg > >>>> > >>>> Shouldn't clocks and regulators be also required ? > >>> > >>> hmm, theoretically yes. Practically, in the case of Acer R13 (mediatek elm) device, > >>> the ANX7688 is powered up and controlled by the Embedded Controller. The kernel only > >>> needs to read few registers from that device for the drm bridge driver. > >>> (also mentioned that in the cover letter). > > I think that for the Chromebook you can assume that these supplies are a > fixed-regulator that are always on. > > >> This may not be a popular opinion, but if the ANX7688 is fully > >> controlled by the EC, I wonder if we shouldn't have an "EC DRM bridge" > >> driver that would interrogate the EC instead :-) > > We can do this, and tbh will be more easy for us, but we were already asked to > do it generic, so ... It's hardly generic if the "generic" driver assumes that there's an EC controlling the device, isn't it ? > > But the driver in patch 2/2 do access the anx7688 device with I2C. > > It does interrogate the EC. > > > >> Is there a risk of bus conflicts if the EC and the main SoC try to > >> access the ANX7688 over I2C at the same time ? > > No, there is a kind of i2c tunnel but you don't talk directly with the ANX7688. > The EC exposes the anx bus control to the AP. Maybe an additional reason to talk to the EC directly instead ? Won't upstreaming an ANX7688 driver that hardcodes assumptions about an EC being present cause issues in the future, when someone will want to extend the driver for a standalone ANX7688 ? The driver will start programming the ANX7688, and the EC won't like it. We would have to add a "this is a real ANX7688" DT property later, which would really not be nice. > > The SoC access the anx7688 though something called 'i2c-tunnel' (see > > google,cros-ec-i2c-tunnel.yaml) > > So the I2C tunnels though the EC (I don't know how this is really implemented to > > be honest). > > > >>>> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > >>>> > >>>>> + > >>>>> +additionalProperties: false > >>>>> + > >>>>> +examples: > >>>>> + - | > >>>>> + #include <dt-bindings/gpio/gpio.h> > >>>>> + #include <dt-bindings/interrupt-controller/irq.h> > >>>>> + > >>>>> + i2c0 { > >>>>> + #address-cells = <1>; > >>>>> + #size-cells = <0>; > >>>>> + > >>>>> + anx7688: anx7688@2c { > >>>>> + compatible = "analogix,anx7688"; > >>>>> + reg = <0x2c>; > >>>>> + avdd33-supply = <®_dcdc1>; > >>>>> + dvdd18-supply = <®_ldo_io1>; > >>>>> + avdd18-supply = <®_ldo_io1>; > >>>>> + avdd10-supply = <®_anx1v0>; > >>>>> + dvdd10-supply = <®_anx1v0>; > >>>>> + hdmi_vt-supply = <®_dldo1>; > >>>>> + enable-gpios = <&pio 3 10 GPIO_ACTIVE_LOW>; /* PD10 */ > >>>>> + reset-gpios = <&pio 3 6 GPIO_ACTIVE_HIGH>; /* PD6 */ > >>>>> + interrupt-parent = <&r_pio>; > >>>>> + interrupts = <0 11 IRQ_TYPE_EDGE_FALLING>; /* PL11 */ > >>>>> + cabledet-gpios = <&r_pio 0 8 GPIO_ACTIVE_HIGH>; /* PL8 */ > >>>>> + vconn-en1-gpios = <&pio 3 9 GPIO_ACTIVE_LOW>; /* PD9 */ > >>>>> + vconn-en2-gpios = <&pio 3 9 GPIO_ACTIVE_LOW>; /* PD9 */ > >>>>> + ports { > >>>>> + #address-cells = <1>; > >>>>> + #size-cells = <0>; > >>>>> + > >>>>> + port@0 { > >>>>> + reg = <0>; > >>>>> + anx7688_in0: endpoint { > >>>>> + remote-endpoint = <&hdmi0_out>; > >>>>> + }; > >>>>> + }; > >>>>> + > >>>>> + port@1 { > >>>>> + reg = <1>; > >>>>> + anx7688_in1: endpoint { > >>>>> + remote-endpoint = <&usbdrd_phy_ss>; > >>>>> + }; > >>>>> + }; > >>>>> + port@2 { > >>>>> + reg = <2>; > >>>>> + anx7688_out: endpoint { > >>>>> + remote-endpoint = <&typec_connector>; > >>>>> + }; > >>>>> + }; > >>>>> + }; > >>>>> + }; > >>>>> + }; -- Regards, Laurent Pinchart