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897cf34e73
This adds nodes to SDM845-dtsi for all the I2C ports, all the SPI ports, and UART9. Note that I2C / SPI / UART are a bit strange on sdm845 because each "serial engine" has 4 pins associated with it and depending on which firmware has been loaded into the serial engine (loaded by the BIOS) the serial engine can behave like an I2C port, a SPI port, or a UART. As per the landed bindings that means that we need to create one node for each possible mode that the port could be in. With 16 serial engines that means 16 x 3 = 48 nodes. We get away with only creating 33 nodes for now because it seems very likely that SDM845-based boards will actually all use the same UART (UART 9) for debug purposes. While another UART could be used for something like Bluetooth communication we can cross that path when we come to it. Some documentation that I saw implied that using a UART for "high speed" communications actually needs yet another different serial engine firmware anyway. Note that quick measurements adding all these nodes adds <10k of extra space per dtb that they're included with. If this becomes a problem we may need to think of a different way to structure this so that boards only get the nodes they need (or figure out how to get dtc to strip 'disabled' nodes). For now it seems OK. These nodes were programmatically generated with a fairly dumb python script. See http://crosreview.com/1091631 for the source. NOTE: at the moment SPI chip select doesn't appear to work in my tests with the latest posted SPI driver. All testing of SPI with this patch has been done by hacking SPI to GPIO chip select. Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Andy Gross <andy.gross@linaro.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
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Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
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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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.