Kernel Source and devicetree for NOTHING Phone(3a) and Phone(3a)Pro
b4e46c9954
Allow SPI peripherals attached to this controller to know what is the maximum transfer size and message size, so they can limit their transfer lengths properly in case they are otherwise capable of larger transfer sizes. For the sc18is602, this is 200 bytes in both cases, since as far as I understand, it isn't possible to tell the controller to keep the chip select asserted after the STOP command is sent. The controller can support SPI messages larger than 200 bytes if cs_change is set for individual transfers such that the portions with chip select asserted are never longer than 200 bytes. What is not supported is just SPI messages with a continuous chip select larger than 200. I don't think it is possible to express this using the current API, so drivers which do send SPI messages with cs_change can safely just look at the max_transfer_size limit. An example of user for this is sja1105_xfer() in drivers/net/dsa/sja1105/sja1105_spi.c which sends by default 64 * 4 = 256 byte transfers. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://lore.kernel.org/r/20210520131238.2903024-3-olteanv@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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.