[Letux-kernel] [RFC 0/8] MIPS: CI20: add HDMI out support

H. Nikolaus Schaller hns at goldelico.com
Thu Feb 27 13:56:56 CET 2020

Hi Sam,

> Am 27.02.2020 um 13:23 schrieb Sam Ravnborg <sam at ravnborg.org>:
> Hi Nikolaus.
> On Wed, Feb 26, 2020 at 08:12:52PM +0100, H. Nikolaus Schaller wrote:
>> This patch series adds HDMI output to the jz4780/CI20 board.
>> It is based on taking the old 3.18 vendor kernel and trying
>> to achieve the same with modern DTS setup and new/modified
>> drivers.
>> Unfortunately, in this first RFC, only EDID and creation of
>> /dev/fb0 are working. Also, HDMI hot plugging is detected.
>> But there is no HDMI output signal. So some tiny piece seems
>> to be missing to enable/configure the Synposys HDMI controller.
>> We need help from the community to fix this.
>> Note: device tree bindings are from 2015 and still seem to
>> fit - except they are not in yaml format.
>> Original authors of most patches are
>> * Paul Boddie <paul at boddie.org.uk>
>> * Zubair Lutfullah Kakakhel <Zubair.Kakakhel at imgtec.com>
>> H. Nikolaus Schaller (2):
>>  drm: ingenic-drm: add MODULE_DEVICE_TABLE
>>  MIPS: CI20: defconfig: configure for DRM_DW_HDMI_JZ4780
>> Paul Boddie (4):
>>  drm: ingenic: add jz4780 Synopsys HDMI driver.
>>  pinctrl: ingenic: add hdmi-ddc pin control group
>>  MIPS: DTS: jz4780: account for Synopsys HDMI driver and LCD controller
>>  MIPS: DTS: CI20: add HDMI setup
>> Zubair Lutfullah Kakakhel (2):
>>  dt-bindings: video: Add jz4780-lcd binding
>>  dt-bindings: video: Add jz4780-hdmi binding
>> .../bindings/display/ingenic-jz4780-hdmi.txt  |  41 ++++++
>> .../bindings/display/ingenic-jz4780-lcd.txt   |  39 ++++++
> New bindings in DT Schema format please...
> We want to have then in a formal launguage so we can use these
> to verify the DT files.

Yes, I know. And I fully support the goal.

But I personally do not have the time to learn the (IMHO brain-twisting)
way the Schema format is working. Especially, I am not interested
in becoming volunteer translator for .txt based schemas developed
by someone else.

So I hope that someone from the community can and is willing to do

Or that there will appear good tools soon. E.g. some GUI
based editor tool would be very helpful so that you don't have
to fight with the yaml indentation rules. Like there are XML
and DTD editors. And even HTML is rarely written manually any more.

IMHO such tools should have been developed and in place *before*
the rule to provide DT schemata is enforced.

Anyways, I have requested for comments (and did expect this one).

BR and thanks,

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