LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Neil Armstrong <narmstrong@baylibre.com>
To: Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	Phong LE <ple@baylibre.com>
Cc: airlied@linux.ie, daniel@ffwll.ch, robh+dt@kernel.org,
	mark.rutland@arm.com, a.hajda@samsung.com, jonas@kwiboo.se,
	jernej.skrabec@siol.net, sam@ravnborg.org, mripard@kernel.org,
	heiko.stuebner@theobroma-systems.com, linus.walleij@linaro.org,
	stephan@gerhold.net, icenowy@aosc.io, broonie@kernel.org,
	mchehab+samsung@kernel.org, davem@davemloft.net,
	gregkh@linuxfoundation.org, Jonathan.Cameron@huawei.com,
	andriy.shevchenko@linux.intel.com,
	dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 2/4] dt-bindings: display: bridge: add it66121 bindings
Date: Fri, 13 Mar 2020 15:12:13 +0100	[thread overview]
Message-ID: <03d5bb7f-db1b-79df-bd46-3ac0f3b4feb1@baylibre.com> (raw)
In-Reply-To: <20200313134013.GC4751@pendragon.ideasonboard.com>

On 13/03/2020 14:40, Laurent Pinchart wrote:
> Hi Phong,
> 
> Thank you for the patch.
> 
> On Wed, Mar 11, 2020 at 01:51:33PM +0100, Phong LE wrote:
>> Add the ITE bridge HDMI it66121 bindings.
>>
>> Signed-off-by: Phong LE <ple@baylibre.com>
>> ---
>>  .../bindings/display/bridge/ite,it66121.yaml  | 98 +++++++++++++++++++
>>  1 file changed, 98 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/display/bridge/ite,it66121.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/display/bridge/ite,it66121.yaml b/Documentation/devicetree/bindings/display/bridge/ite,it66121.yaml
>> new file mode 100644
>> index 000000000000..1717e880d130
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/display/bridge/ite,it66121.yaml
>> @@ -0,0 +1,98 @@
>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/display/bridge/ite,it66121.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: ITE it66121 HDMI bridge Device Tree Bindings
>> +
>> +maintainers:
>> +  - Phong LE <ple@baylibre.com>
>> +  - Neil Armstrong <narmstrong@baylibre.com>
>> +
>> +description: |
>> +  The IT66121 is a high-performance and low-power single channel HDMI
>> +  transmitter, fully compliant with HDMI 1.3a, HDCP 1.2 and backward compatible
>> +  to DVI 1.0 specifications.
>> +
>> +properties:
>> +  compatible:
>> +    const: ite,it66121
>> +
>> +  reg:
>> +    maxItems: 1
>> +    description: base I2C address of the device
>> +
>> +  reset-gpios:
>> +    maxItems: 1
>> +    description: GPIO connected to active low reset
>> +
>> +  vrf12-supply:
>> +    maxItems: 1
>> +    description: Regulator for 1.2V analog core power.
>> +
>> +  vcn33-supply:
>> +    maxItems: 1
>> +    description: Regulator for 3.3V digital core power.
>> +
>> +  vcn18-supply:
>> +    maxItems: 1
>> +    description: Regulator for 1.8V IO core power.
>> +
>> +  interrupts:
>> +    maxItems: 1
>> +
>> +  pclk-dual-edge:
>> +    maxItems: 1
>> +    description: enable pclk dual edge mode.
> 
> I'm having a bit of trouble understanding how this operates. Looking at
> the driver code the property is only taken into account to calculate the
> maximum allowed frequency. How is the IT66121 configured for single vs.
> dual pixel clock edge mode ?


Dual edge mode is Dual-Data-Rate mode, the normal mode is MEDIA_BUS_FMT_RGB888_1X24 and dual edge is
MEDIA_BUS_FMT_RGB888_2X12_LE (or MEDIA_BUS_FMT_RGB888_2X12_BE, not sure) on a single clock period.

This should be negociated at runtime, but the bus width should be specified somewhere to select
one of the modes.

Neil

> 
>> +
>> +  port:
>> +    type: object
>> +
>> +    properties:
>> +      endpoint:
>> +        type: object
>> +        description: |
>> +          Input endpoints of the bridge.
>> +
>> +    required:
>> +      - endpoint
> 
> You should have two ports, one for the bridge input, and one for the
> bridge output.
> 
>> +
>> +required:
>> +  - compatible
>> +  - reg
>> +  - reset-gpios
>> +  - vrf12-supply
>> +  - vcn33-supply
>> +  - vcn18-supply
>> +  - interrupts
>> +  - port
>> +
>> +additionalProperties: false
>> +
>> +examples:
>> +  - |
>> +    i2c6 {
>> +      #address-cells = <1>;
>> +      #size-cells = <0>;
>> +
>> +      it66121hdmitx: it66121hdmitx@4c {
>> +        compatible = "ite,it66121";
>> +        pinctrl-names = "default";
>> +        pinctrl-0 = <&ite_pins_default>;
>> +        vcn33-supply = <&mt6358_vcn33_wifi_reg>;
>> +        vcn18-supply = <&mt6358_vcn18_reg>;
>> +        vrf12-supply = <&mt6358_vrf12_reg>;
>> +        reset-gpios = <&pio 160 1 /* GPIO_ACTIVE_LOW */>;
>> +        interrupt-parent = <&pio>;
>> +        interrupts = <4 8 /* IRQ_TYPE_LEVEL_LOW */>;
>> +        reg = <0x4c>;
>> +        pclk-dual-edge;
>> +
>> +        port {
>> +          it66121_in: endpoint {
>> +            remote-endpoint = <&display_out>;
>> +          };
>> +        };
>> +      };
>> +    };
> 


  reply	other threads:[~2020-03-13 14:12 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-11 12:51 [PATCH v2 0/4] Add it66121 driver Phong LE
2020-03-11 12:51 ` [PATCH v2 1/4] dt-bindings: add ITE vendor Phong LE
2020-03-23 22:04   ` Rob Herring
2020-03-11 12:51 ` [PATCH v2 2/4] dt-bindings: display: bridge: add it66121 bindings Phong LE
2020-03-13 13:40   ` Laurent Pinchart
2020-03-13 14:12     ` Neil Armstrong [this message]
2020-03-13 14:17       ` Laurent Pinchart
2020-03-13 15:29         ` Neil Armstrong
2020-03-23 22:09   ` Rob Herring
2020-03-11 12:51 ` [PATCH v2 3/4] drm: bridge: add it66121 driver Phong LE
2020-03-11 13:55   ` Andy Shevchenko
2020-03-12  0:53     ` Laurent Pinchart
2020-03-12  8:40       ` Andy Shevchenko
2020-03-13 13:55   ` Laurent Pinchart
2020-06-11 15:22   ` Drew Fustini
2020-03-11 12:51 ` [PATCH v2 4/4] MAINTAINERS: add it66121 HDMI bridge driver entry Phong LE
2020-03-11 13:22   ` Andy Shevchenko

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=03d5bb7f-db1b-79df-bd46-3ac0f3b4feb1@baylibre.com \
    --to=narmstrong@baylibre.com \
    --cc=Jonathan.Cameron@huawei.com \
    --cc=a.hajda@samsung.com \
    --cc=airlied@linux.ie \
    --cc=andriy.shevchenko@linux.intel.com \
    --cc=broonie@kernel.org \
    --cc=daniel@ffwll.ch \
    --cc=davem@davemloft.net \
    --cc=devicetree@vger.kernel.org \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=heiko.stuebner@theobroma-systems.com \
    --cc=icenowy@aosc.io \
    --cc=jernej.skrabec@siol.net \
    --cc=jonas@kwiboo.se \
    --cc=laurent.pinchart@ideasonboard.com \
    --cc=linus.walleij@linaro.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=mchehab+samsung@kernel.org \
    --cc=mripard@kernel.org \
    --cc=ple@baylibre.com \
    --cc=robh+dt@kernel.org \
    --cc=sam@ravnborg.org \
    --cc=stephan@gerhold.net \
    --subject='Re: [PATCH v2 2/4] dt-bindings: display: bridge: add it66121 bindings' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).