Previously the driver used more low level operations like iicbus_start
and iicbus_write. The problem is that those operations are not
implemented by iicbus(4) and the calls were effectively routed to
a driver to which the bus is attached.
But not all of the controllers implement such low level operations
while all of the drivers are expected to have iicbus_transfer.
While there fix incorrect implementation of iicsmb_bwrite and iicsmb_bread.
The former should send a byte count before the actual bytes, while the
latter should first receive the byte count and then receive the bytes.
I have tested only these commands:
- quick (r/w)
- send byte
- receive byte
- read byte
- write byte
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D8170
f1519c0157