56d074d26c
The optional variants for the gpiod_get() family of functions return NULL
if the GPIO in question is not associated with this device. They return
ERR_PTR() on any other error. NULL descriptors are graciously handled by
GPIOLIB and can be safely passed to any of the GPIO consumer interfaces
as they will return 0 and act as if the function succeeded. If one is
using the optional variant, then there's no point in checking for NULL.
Fixes: 6845667146a2 ("Bluetooth: hci_qca: Fix NULL vs IS_ERR_OR_NULL check in qca_serdev_probe")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
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.