Hans de Goede 3860152c10 ACPI: scan: Do not increase dep_unmet for already met dependencies
commit d730192ff0246356a2d7e63ff5bd501060670eec upstream.

On the Toshiba Encore WT10-A tablet the BATC battery ACPI device depends
on 3 other devices:

            Name (_DEP, Package (0x03)  // _DEP: Dependencies
            {
                I2C1,
                GPO2,
                GPO0
            })

acpi_scan_check_dep() adds all 3 of these to the acpi_dep_list and then
before an acpi_device is created for the BATC handle (and thus before
acpi_scan_dep_init() runs) acpi_scan_clear_dep() gets called for both
GPIO depenencies, with free_when_met not set for the dependencies.

Since there is no adev for BATC yet, there also is no dep_unmet to
decrement. The only result of acpi_scan_clear_dep() in this case is
dep->met getting set.

Soon after acpi_scan_clear_dep() has been called for the GPIO dependencies
the acpi_device gets created for the BATC handle and acpi_scan_dep_init()
runs, this sees 3 dependencies on the acpi_dep_list and initializes
unmet_dep to 3. Later when the dependency for I2C1 is met unmet_dep
becomes 2, but since the 2 GPIO deps where already met it never becomes 0
causing battery monitoring to not work.

Fix this by modifying acpi_scan_dep_init() to not increase dep_met for
dependencies which have already been marked as being met.

Fixes: 3ba12d8de3fa ("ACPI: scan: Reduce overhead related to devices with dependencies")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: 6.5+ <stable@vger.kernel.org> # 6.5+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-17 11:19:26 +02:00
2023-08-31 12:20:12 -07:00
2024-04-03 15:28:17 +02:00
2024-02-16 19:10:43 +01:00
2022-09-28 09:02:20 +02:00
2022-10-10 12:00:45 -07:00
2024-04-13 13:07:41 +02:00

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.
Description
No description provided
Readme 5.7 GiB
Languages
C 97.6%
Assembly 1%
Shell 0.5%
Python 0.3%
Makefile 0.3%