[PATCHv2 0/3] dw-hdmi: add property to disable CEC

Neil Armstrong narmstrong at baylibre.com
Sat Mar 24 06:41:38 PDT 2018

Hi Martin,

> Le 24 mars 2018 à 12:00, Martin Blumenstingl <martin.blumenstingl at googlemail.com> a écrit :
> Hello Hans, Hi Neil,
> (apologies in advance if any of this is wrong, I don't have any CEC
> capable TV so I can't test it)
> On Fri, Mar 23, 2018 at 1:59 PM, Hans Verkuil <hverkuil at xs4all.nl> wrote:
>> From: Hans Verkuil <hans.verkuil at cisco.com>
>> Some boards (amlogic) have two CEC controllers: the DesignWare controller
>> and their own CEC controller (meson ao-cec).
> as far as I understand the Amlogic Meson SoCs have two domains:
> - AO (always-on, powered even in suspend mode) where meson-ao-cec can
> wake up the system from suspend
> - EE (everything else, not powered during suspend) where dw-hdmi-cec lives

Exact, except … the EE CEC is not hooked to the DW-HDMI TX but the RX, and thus cannot be used on GXBB/GXL/GXM.

> this far everything is OK
>> Since the CEC line is not hooked up to the DW controller we need a way
>> to disable that controller. This patch series adds the cec-disable
>> property for that purpose.
> drivers/pinctrl/meson/pinctrl-meson-gxbb.c has ao_cec_pins and
> ee_cec_pins, both use GPIOAO_12
> drivers/pinctrl/meson/pinctrl-meson-gxl.c has ao_cec_pins and
> ee_cec_pins, both use GPIOAO_8
> @Neil: do you know if the CEC signal routing is:
> ao_cec_pins -> meson-ao-cec
> ee_cec_pins -> dw-hdmi-cec

It’s hooked to the DW-HDMI RX IP used in the TV SoCs.

> I'm curious because if both CEC controllers can be used then it might
> be worth mentioning this in the cover-letter and patch description

Initially I thought it was hooked to the DW-HDMI TX, but no, I guess I should remove the ee_cec pinmux…


> Regards
> Martin

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