[PATCH 0/6] TDA998x CEC support

[Russell King - ARM Linux]

On Wed, Nov 29, 2017 at 01:43:27PM +0100, Hans Verkuil wrote:
> On 11/29/17 10:11, Russell King - ARM Linux wrote:
> > On Wed, Nov 29, 2017 at 08:41:45AM +0100, Hans Verkuil wrote:
> >> Hi Russell,
> >>
> >> On 11/29/2017 12:17 AM, Russell King - ARM Linux wrote:
> >>> Hi,
> >>>
> >>> This patch series adds CEC support to the DRM TDA998x driver.  The
> >>> TDA998x family of devices integrate a TDA9950 CEC at a separate I2C
> >>> address from the HDMI encoder.
> >>>
> >>> Implementation of the CEC part is separate to allow independent CEC
> >>> implementations, or independent HDMI implementations (since the
> >>> TDA9950 may be a separate device.)
> >>
> >> Thank you for this patch series! I assume you are testing this with a
> >> BeagleBone Black? If so, do you have a patch for the dts that hooks up the
> >> interrupt? If possible, I'd like to test this with my BBB.
> > 
> > I don't, I test it on the SolidRun Dove Cubox.  I can't help with BBB.
> > 
> 
> Can you post the dts tda snippet you use for the SolidRun Dove Cubox?
> Or just mail the whole thing to me, or point to a git repo where you
> have it.
> 
> I can use that as a starting point for adding CEC support to the BBB.

There's two patches.  Here's the addition of tda998x to dove-cubox.dts:

+       tda998x: hdmi-encoder {
+               compatible = "nxp,tda998x";
+               reg = <0x70>;
+               video-ports = <0x234501>;
+               interrupts-extended = <&gpio0 27 IRQ_TYPE_LEVEL_LOW>;
+
+               port {
+                       tda998x_video: endpoint {
+                               remote-endpoint = <&lcd0_rgb>;
+                       };
+               };
+       };

And then adding tda998x cec requires:

        tda998x: hdmi-encoder {
                compatible = "nxp,tda998x";
+               calib-gpio = <&gpio0 27 0>;
                reg = <0x70>;
                video-ports = <0x234501>;
                interrupts-extended = <&gpio0 27 IRQ_TYPE_LEVEL_LOW>;

The problem that I see with BBB (I assume am335x-boneblack-common.dtsi)
is that the tda998x doesn't mention an interrupt - if the interrupt
isn't wired to a GPIO, you can't calibrate the TDA998x CEC FRO, and CEC
will not work.

The same problem appears on ARM's evaluation boards that use the TDA998x.
The chip is present but there's no indication whether the interrupt pin
is wired.

That means, despite having several platforms with a TDA998x present, the
only one I can test CEC with is the Dove Cubox.

(At the moment, I can't test CEC as a regular part of testing as I've
"lost" my TV to the living room for the rest of the family to use...
need to repair their normal TV...)

-- 
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