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misc: lis3lv02d_i2c: Fix regulators getting en-/dis-abled twice on suspend/resume

Steve Best requested to merge sfbest/centos-stream-9:36934 into main

JIRA: https://issues.redhat.com/browse/RHEL-36934
CVE: CVE-2024-35824

Build Info: https://brewweb.engineering.redhat.com/brew/taskinfo?taskID=61329759

Tested: Did sanity load and unload of the module using Intel (dell-per6615-01) system.

commit ac3e0384073b2408d6cb0d972fee9fcc3776053d
Author: Hans de Goede hdegoede@redhat.com
Date: Tue Feb 20 20:00:35 2024 +0100

misc: lis3lv02d_i2c: Fix regulators getting en-/dis-abled twice on suspend/resume  

When not configured for wakeup lis3lv02d_i2c_suspend() will call  
lis3lv02d_poweroff() even if the device has already been turned off  
by the runtime-suspend handler and if configured for wakeup and  
the device is runtime-suspended at this point then it is not turned  
back on to serve as a wakeup source.  

Before commit b1b9f7a49440 ("misc: lis3lv02d_i2c: Add missing setting  
of the reg_ctrl callback"), lis3lv02d_poweroff() failed to disable  
the regulators which as a side effect made calling poweroff() twice ok.  

Now that poweroff() correctly disables the regulators, doing this twice  
triggers a WARN() in the regulator core:  

unbalanced disables for regulator-dummy  
WARNING: CPU: 1 PID: 92 at drivers/regulator/core.c:2999 _regulator_disable  
...  

Fix lis3lv02d_i2c_suspend() to not call poweroff() a second time if  
already runtime-suspended and add a poweron() call when necessary to  
make wakeup work.  

lis3lv02d_i2c_resume() has similar issues, with an added weirness that  
it always powers on the device if it is runtime suspended, after which  
the first runtime-resume will call poweron() again, causing the enabled  
count for the regulator to increase by 1 every suspend/resume. These  
unbalanced regulator_enable() calls cause the regulator to never  
be turned off and trigger the following WARN() on driver unbind:  

WARNING: CPU: 1 PID: 1724 at drivers/regulator/core.c:2396 _regulator_put  

Fix this by making lis3lv02d_i2c_resume() mirror the new suspend().  

Fixes: b1b9f7a49440 ("misc: lis3lv02d_i2c: Add missing setting of the reg_ctrl callback")  
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>  
Closes: https://lore.kernel.org/regressions/5fc6da74-af0a-4aac-b4d5-a000b39a63a5@molgen.mpg.de/  
Cc: stable@vger.kernel.org  
Cc: regressions@lists.linux.dev  
Signed-off-by: Hans de Goede <hdegoede@redhat.com>  
Tested-by: Paul Menzel <pmenzel@molgen.mpg.de> # Dell XPS 15 7590  
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>  
Link: https://lore.kernel.org/r/20240220190035.53402-1-hdegoede@redhat.com  
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Steve Best sbest@redhat.com

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