The si3210 is a SLIC device providing a complete analog telephone
interface and therefore frequently used in soho router.
The si3210 have a native spi interface to be controlled by the CPU
but currently there is no dedicated driver in lede.
Adding a registration for this device in spidev allow to control the
device in user space.
This way of patching is also in line with the rationale of the spidev
driver, see: http://marc.info/?t=148145791900001&r=1&w=2
The si3210 has been also added in the DWR-512 DT to properly describe
the HW.
Signed-off-by: Giuseppe Lippolis <giu.lippolis@gmail.com>
The Dlink DWR-512-B modem is a ralink 5350 processor based embedding
a 3G mini-pcie router.
The oem JBOOT bootloader has to be replaced by a RT5350 SDK
U-Boot such as https://github.com/stevenylai/ralink_sdk - U-Boot
configured for the RT5350 256MiB SDR.
Main reason to change the bootloader is the encrypted header used to
store the kernel image. In this way an image can only be generated
using the propietary binboy tool (included in the GPL distribution
from Dlink). The binboy tool doesn't allow to modify the kernel/rootfs
partition scheme. This is considered a big constraint (limited kernel
size and inefficient usage of flash space).
For interested people I pubblished the details of my investigation
about the encrypted firmware header here:
http://lists.infradead.org/pipermail/lede-dev/2016-October/003435.html
Signed-off-by: Giuseppe Lippolis <giu.lippolis@gmail.com>
