Zev Weiss f4e6960f4f hwmon: (nct6775) Fix platform driver suspend regression
Commit c3963bc0a0 ("hwmon: (nct6775) Split core and platform
driver") introduced a slight change in nct6775_suspend() in order to
avoid an otherwise-needless symbol export for nct6775_update_device(),
replacing a call to that function with a simple dev_get_drvdata()
instead.

As it turns out, there is no guarantee that nct6775_update_device()
is ever called prior to suspend. If this happens, the resume function
ends up writing bad data into the various chip registers, which results
in a crash shortly after resume.

To fix the problem, just add the symbol export and return to using
nct6775_update_device() as was employed previously.

Reported-by: Zoltán Kővágó <dirty.ice.hu@gmail.com>
Tested-by: Zoltán Kővágó <dirty.ice.hu@gmail.com>
Fixes: c3963bc0a0 ("hwmon: (nct6775) Split core and platform driver")
Cc: stable@kernel.org
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Link: https://lore.kernel.org/r/20220810052646.13825-1-zev@bewilderbeest.net
[groeck: Updated description]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2022-08-10 06:37:01 -07:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
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In order to build the documentation, use ``make htmldocs`` or
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    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
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