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The current method to calculate the ddr clk period is wrong. Therefore the ths_term calculation is incorrect. Also it was wrongly assumed that the ths_settle parameter was based on the control clock instead of the pixel clock. Since the DPHY can tolerate quite a bit a of variation, capture was still mostly working with the 2 tested modes when the pixel clock was close to the control clock (i.e. 96 Mhz). But it would quickly stops working when using different modes or when customers used different sensors altogether. Calculating the DDRClk period needs to take into account the pixel bit width and the number of active data lanes. Based on the latest technical reference manual these parameters should now be calculated as follows: THS_TERM: Programmed value = floor(20 ns/DDRClk period) THS_SETTLE: Programmed value = floor(105 ns/DDRClk period) + 4 Also originally 'depth' was used to represent the number of bits a pixel would use once stored in memory (i.e. the container size). To accurately calculate the THS_* parameters we need to use the actual number of bits per pixels coming in from the sensor. So we are renaming 'depth' to 'bpp' (bits per pixels) and update the format table to show the actual number of bits per pixel being received. The "container" size will be derived from the "bpp" value. Signed-off-by: Benoit Parrot <bparrot@ti.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
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.