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Each Video Front End - VFE - has a variable number of Raw Data Interfaces -
RDIs associated with it.
The CAMSS code started from a naive implementation where a fixed define was
used as a control in a for(){} loop iterating through RDIs.
That model scales badly. An attempt was made with VFE_LINE_NUM_GEN2 and
VFE_LINE_NUM_GEN1 to differentiate between SoCs but, the problem with that
is "gen1" and "gen2" have no meaning in the silicon. There is no fixed
constraint in the silicon between VFE and RDI, it is entirely up to the SoC
designers how many VFEs are populated and how many RDIs to associate with
each VFE.
As an example sdm845 has VFE version 175 and sm8250 VFE version 480.
sdm845 has 2 VFEs with 4 RDIs and 1 VFE Lite with 4 RDIs.
sm8250 has 2 VFEs with 3 RDIs and 2 VFE Lite with 4 RDIs.
Clearly then we need a more granular model to capture the necessary data.
The defines have gone away to be replaced with per-SoC data but, we haven't
populated the parameter data with the real values.
Let's call those values out now
msm8916:
1 x VFE
3 x RDI per VFE (not 4)
msm8996:
2 x VFE
3 x RDI per VFE (not 4)
sdm660:
2 x VFE
3 x RDI per VFE (not 4)
sdm845:
2 x VFE
4 x RDI per VFE (not 3)
1 x VFE Lite
4 x RDI per VFE Lite (not 3)
sm8250:
2 x VFE
3 x RDI per VFE (not 4)
2 x VFE Lite
4 x RDI per VFE Lite
This more complex and correct mapping was not possible prior to passing
values via driver data. Now that we have that change in place we can
correctly map VFEs to RDIs for each VFE.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Acked-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.