[linux-dvb] Re: CX88 i2c issue w/ DVB tuners

[Ralph Metzler <rjkm@metzlerbros.de>]

Gerd Knorr writes:
 > Ralph Metzler <rjkm@metzlerbros.de> writes:
 > 
 > > I think before (a year or so ago) when possible improvements 
 > > of the kernel i2c driver for DVB were discussed on this list 
 > > one of the ideas was to add a type field to the i2c client. 
 > > Something like I2C_DVB_DEMOD, I2C_DVB_TUNER, I2C_ANALOG_TUNER, 
 > > I2C_ANALOG_SOUND_THINGY_GADGET, etc.
 > > The i2c driver could then choose in the attach function what kind of
 > > clients to accept and how to configure them.
 > 
 > We have something like that now in the mainline kernel: the .class
 > field in both adapters and clients which can be used to figure
 > whenever attaching makes sense or not.  That helps reducing address
 > clashes alot and was actually added for dvb because it was a real-live
 > issue that lm_sensor chips probed on the dvb i2c bus and confused the
 > frontends by doing so.

Hmm, but clients do not seem to have that class field yet?!
If an adapter wants to have several kinds of clients it still cannot 
distinguish them during attach.
 
 > It doesn't help through in the case we have a conflict between analog
 > + digital tuner chips and tv cards which can do both analog + digital
 > TV ...

True.

Ralph