mirror of
https://github.com/ukui/kernel.git
synced 2026-03-09 10:07:04 -07:00
Christian Hoff
d55bda1b3e
"of_get_named_gpio()" returns a negative error value if it fails and drivers should check for this. This missing check was now added to the matrix_keypad driver. In my case "of_get_named_gpio()" returned -EPROBE_DEFER because the referenced GPIOs belong to an I/O expander, which was not yet probed at the point in time when the matrix_keypad driver was loading. Because the driver did not check for errors from the "of_get_named_gpio()" routine, it was assuming that "-EPROBE_DEFER" is actually a GPIO number and continued as usual, which led to further errors like this later on: WARNING: CPU: 3 PID: 167 at drivers/gpio/gpiolib.c:114 gpio_to_desc+0xc8/0xd0 invalid GPIO -517 Note that the "GPIO number" -517 in the error message above is actually "-EPROBE_DEFER". As part of the patch a misleading error message "no platform data defined" was also removed. This does not lead to information loss because the other error paths in matrix_keypad_parse_dt() already print an error. Signed-off-by: Christian Hoff <christian_hoff@gmx.net> Suggested-by: Sebastian Reichel <sre@kernel.org> Reviewed-by: Sebastian Reichel <sre@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.