[ADV7393] DRM Encoder Slave or DRM Bridge

[Vikas Patil]

On Fri, Sep 23, 2016 at 4:32 PM, Tomi Valkeinen <tomi.valkeinen at ti.com> wrote:
> On 23/09/16 13:08, Vikas Patil wrote:
>> Hi Tomi,
>>
>> I added the missing check for "OMAP_DISPLAY_TYPE_VENC" in function
>> omap_connector_detect @ gpu/drm/omapdrm/omap_connector.c and now
>> modetest  seems to be showing correct status and connections.
>
> Is there a cable detection support in the ADV hardware & driver? If not,
> then the cable connection status is "unknown". It should still work if
> the output is enabled manually. I think. I don't have any boards with
> analog tv out..
>

It seems adv7393 has the support for "cable detection" but I am not
sure How to utilize it in driver? Also what ddi you mean by " It
should still work if
 the output is enabled manually."?

>From Datasheet:
CABLE DETECTION
Subaddress 0x10, Bits[1:0]
The ADV7390/ADV7391/ADV7392/ADV7393 include an Analog Devices
proprietary cable detection feature. The cable detection feature is
available on DAC 1 and DAC 2 when operating in full-drive mode (RSET =
510 Ω, RL = 37.5 Ω, assuming a connected cable). The feature is not
available in low-drive mode (RSET = 4.12 kΩ, RL = 300 Ω). For a DAC to
be monitored, the DAC must be powered up in Subaddress 0x00.
The cable detection feature can be used with all SD, ED, and HD video
standards. It is available for all output configurations, that is,
CVBS, Y-C, YPrPb, and RGB output configurations.

> But yes, your change is an easy hack to force the output on.
>
>> But still I could not see kmscube on panel and can see some flicker is
>> going on display. I think I need to understand about what display
>> timing I could use as interlace doesn't seems to be supported as I
>> mentioned above.
>
> Yes, sounds like a video timings issue.
>

Will check with different timing and doubling the clock as suggested
for non-interlace format.

Thanks & Regards,
Vikash