[alsa-devel] [PATCH v9 1/4] drm/i2c: tda998x: Add DT support for audio

Russell King - ARM Linux linux at arm.linux.org.uk
Mon Jan 12 15:04:56 CET 2015


On Mon, Jan 12, 2015 at 02:59:57PM +0100, Philipp Zabel wrote:
> Am Montag, den 12.01.2015, 12:25 +0000 schrieb Russell King - ARM Linux:
> > It's not quite that simple, because the SPDIF AP pins are multiplexed
> > with the I2S pins - and there is variation between chip models and
> > packages.
> >
> > So, it's probably best if port at 0 is the video port, and then port at 1..n
> > can describe the audio inputs, including a property which specifies
> > whether they are I2S or SPDIF, and the value to be programmed into
> > the AP enable register (which is a bit field of the AP pins which
> > should be unmasked.)  I guess we can re-use the reg= property for that
> > value, since video will always be zero.
> 
> Note that of_graph_parse_endpoint interprets the port node's reg
> property as port id. And the unit address part of the node name should
> match the first address in the reg property.

So that's not going to work very well... because the AP register is a
bitmask.

I guess we could specify a node unit and reg, which the code otherwise
ignores, and specify a philipps,ap-mask = property for the audio ports
instead.

-- 
FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up
according to speedtest.net.


More information about the Alsa-devel mailing list