[PATCH v3 2/2] drm: bridge/dw_hdmi: add dw hdmi i2c bus adapter support

Philipp Zabel p.zabel at pengutronix.de
Mon Aug 31 02:22:43 PDT 2015

Hi Vladimir,

Am Montag, den 31.08.2015, 00:34 +0300 schrieb Vladimir Zapolskiy:
> The change adds support of internal HDMI I2C master controller, this
> subdevice is used by default, if "ddc-i2c-bus" DT property is omitted.

I think this should be mentioned in

> The main purpose of this functionality is to support reading EDID from
> an HDMI monitor on boards, which don't have an I2C bus connected to
> DDC pins.
> The current implementation does not support "I2C Master Interface
> Extended Read Mode" to read data addressed by non-zero segment
> pointer, this means that if EDID has more than 1 extension blocks,
> EDID reading operation won't succeed, in my practice all tested HDMI
> monitors have at maximum one extension block.
> Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy at mentor.com>
> ---
> The change is based on today's v4.2, please let me know, if it should be rebased.
> The change has compilation dependency on I2CM_ADDRESS register name fix,
> see http://lists.freedesktop.org/archives/dri-devel/2015-May/082980.html
> From http://lists.freedesktop.org/archives/dri-devel/2015-May/082981.html
> v1 of the change was
>   Tested-by: Philipp Zabel <p.zabel at pengutronix.de>
> but I hesitate to add the tag here due to multiple updates in v2.

Tested again, v2 still works fine on Nitrogen6X with HDMI monitor.


More information about the dri-devel mailing list