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8b57b11bc4
Change the type of the diagnostic message: "no DMA channels available, using PIO" from debug to warning. The lack of an available DMA channel is very important regard the spi-pxa2xx performance. The transfer speed can be reduced more than 50%. So it is very important to warn the user about this, without enabling the full SPI debug with CONFIG_SPI_DEBUG. Moreover, enabling the full SPI debug only to enable this specific debug message, the dmesg buffer fills quickly with a lot of repetitive information during the SPI data transfer. This cause the loss of all the first important messages written during the initialization. Signed-off-by: Flavio Suligoi <f.suligoi@asem.it> Signed-off-by: Mark Brown <broonie@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.