0285042fed
To prepare for adding SoundWire the probe must be split into three parts: 1) The bus-specific probe 2) Common bus-agnostic probe steps 3) Initialization of the peripheral registers Step (3) must be separate because on SoundWire devices the probe must enable power supplies and release reset so that the peripheral can be enumerated by the bus, but it isn't possible to access registers until enumeration has completed. The call to devm_snd_soc_register_component() must be done at stage (2) so that it can EPROBE_DEFER if necessary. In SoundWire systems stage (3) is not a probe event so a deferral at this stage would not result in re-probing dependencies. A new init_done flag indicates that the chip has been identified and initialized. This is used to prevent cs42l42_remove(), cs42l42_suspend(), cs42l42_restore() and cs42l42_irq_thread() from attempting register accesses if the chip was not successfully initialized. Although this cannot happen on I2C, because the entire probe would fail, it is possible on SoundWire if probe succeeds but the cs42l42 is never enumerated. Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com> Signed-off-by: Martin Povišer <povik+lin@cutebit.org> Link: https://lore.kernel.org/r/20220915094444.11434-5-povik+lin@cutebit.org 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.