1b8b20868a
Drivers should return -ENOTTY ("Inappropriate I/O control operation")
when an ioctl isn't supported, while -EINVAL is used for invalid
arguments.
Fix up the TIOCMGET, TIOCMSET and TIOCGICOUNT helpers which returned
-EINVAL when a tty driver did not implement the corresponding
operations.
Note that the TIOCMGET and TIOCMSET helpers predate git and do not get a
corresponding Fixes tag below.
Fixes: d281da7ff6f7 ("tty: Make tiocgicount a handler")
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210407095208.31838-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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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
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the problems which may result by upgrading your kernel.