[sane-devel] Questions about the genesys backend and the corresponding frontends (Wolfson Microelectronics)

[Jean-Baka Domelevo-Entfellner]

Hi!
Following on my project to include support for the OpticFilm 7200 (by
Plustek) to the genesys backend, I have some questions to the
maintainer(s) of the latter:

1) Are the AFEs taken into account for the moment all made by Wolfson
? The Genesys_Frontend stuctures are different for the UMAX, ST12,
HP2400c, etc. I wonder why.

2) Concerning this same structure, I don't understand exactly the
meaning of the four values put in reg and the three put in reg2.
Apparently being register contents corresponding to extra registers
(we already have the three gain registers and the three offset
registers), it would allow for seven configuration registers for the
AFE, which looks far too much for me. In my case the AFE is the
AD9826, and it has only two 8-bit configuration registers.

3) At the same point, in "sign", correct me if this is not the sign
bit (bit#8, i.e. the ninth of the field) of the offset for each of the
three channels.

4) There seem to be some mistakes (or things I don't understand :-))
in the addresses given to the sanei_genesys_fe_write_data function, in
genesys.c and genesys_gl841.c. For instance, for the red gain, I can
see the address 0x28, which doesn't seem to match the Wolfson WM8192
chip documentation (please indicate which is the exact AFE used, but I
think the register addresses are pretty much the same for all WM
chips).

5) As I could have other questions in the near future, please allow me
to write directly to you (dear maintainer(s)) in the future, cause it
could become boring for the other readers of the list. Problem is I
don't know who is in the current maintainer's team concerning the
genesys backend (Pierre ? Stéphane ? Gerhard ? Henning ? Maybe I will
do some kind of temporary restricted ml...)

See you, and thanks for your help.
JB