Re: [PATCH] ASoC: tda998x: Fix lack of required reg in DT documentation

[Russell King - ARM Linux <linux@arm.linux.org.uk>]

On Thu, Mar 20, 2014 at 02:52:21PM +0100, Jean-Francois Moine wrote:
> Thanks for the link.
> 
> OK, then, as the linux tda998x driver handles only the tda 19988 and
> 19989 chips, the HDMI I2C address is always 0x70.
> 
> So, question: Russell and Sebastian, do you still want an other patch?
> 
> Other question: the CEC address is hard-coded to 0x34 in the driver.
> Should it be configurable in the DT?

As we haven't had a mainline non-rc kernel release with this in yet,
we have more scope in what we can do to sort this out.  What I'd
suggest is:

1. change the DT compatible strings the driver has to accept both
   nxp,tda19988 and nxp,tda19989, and set the appropriate device
   in the DT file (tda19988).  I'm a bit nervous about using
   "nxp,tda1998x" in case we're clashing with devices with different
   characteristics.

2. specify that the i2c reg address must exist, but not specify what
   it should be - leave that open.

3. assume that there's a CEC at 0x34 for these two devices.

If we wish to extend support to tda998x, then we'd need to modify the
driver quite a bit anyway.

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