4c8d49bc47
The driver must free the IRQ in remove() to prevent the potential race where an IRQ starts to be handled while the driver is being removed but devres has not yet called free_irq(). However, the driver can run without an interrupt but devm_free_irq() will hit a WARN() if no devres-managed interrupt was ever created. Fix this by only attempting to create the interrupt handler if the hardware config specified an interrupt, and failing probe() if the interrupt could not be created. This means that in cs42l42_remove() an interrupt must have been registered if the irq number is valid and therefore it is safe to call devm_free_irq(). Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com> Link: https://lore.kernel.org/r/20211015133619.4698-16-rf@opensource.cirrus.com 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.