platform/x86: wmi: Skip blocks with zero instances

[ Upstream commit cbf54f37600e874d82886aa3b2f471778cae01ce ]

Some machines like the HP Omen 17 ck2000nf contain WMI blocks
with zero instances, so

platform/x86: wmi: Skip blocks with zero instances

[ Upstream commit cbf54f37600e874d82886aa3b2f471778cae01ce ]

Some machines like the HP Omen 17 ck2000nf contain WMI blocks
with zero instances, so any WMI driver which tries to handle the
associated WMI device will fail.
Skip such WMI blocks to avoid confusing any WMI drivers.

Reported-by: Alexis Belmonte <alexbelm48@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218188
Fixes: bff431e49ff5 ("ACPI: WMI: Add ACPI-WMI mapping driver")
Tested-by: Alexis Belmonte <alexbelm48@gmail.com>
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20231129181654.5800-1-W_Armin@gmx.de
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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platform/x86: wmi: Fix opening of char device

[ Upstream commit eba9ac7abab91c8f6d351460239108bef5e7a0b6 ]

Since commit fa1f68db6ca7 ("drivers: misc: pass miscdevice pointer via
file private data")

platform/x86: wmi: Fix opening of char device

[ Upstream commit eba9ac7abab91c8f6d351460239108bef5e7a0b6 ]

Since commit fa1f68db6ca7 ("drivers: misc: pass miscdevice pointer via
file private data"), the miscdevice stores a pointer to itself inside
filp->private_data, which means that private_data will not be NULL when
wmi_char_open() is called. This might cause memory corruption should
wmi_char_open() be unable to find its driver, something which can
happen when the associated WMI device is deleted in wmi_free_devices().

Fix the problem by using the miscdevice pointer to retrieve the WMI
device data associated with a char device using container_of(). This
also avoids wmi_char_open() picking a wrong WMI device bound to a
driver with the same name as the original driver.

Fixes: 44b6b7661132 ("platform/x86: wmi: create userspace interface for drivers")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20231020211005.38216-5-W_Armin@gmx.de
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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platform/x86: wmi: Fix probe failure when failing to register WMI devices

[ Upstream commit ed85891a276edaf7a867de0e9acd0837bc3008f2 ]

When a WMI device besides the first one somehow fails to regis

platform/x86: wmi: Fix probe failure when failing to register WMI devices

[ Upstream commit ed85891a276edaf7a867de0e9acd0837bc3008f2 ]

When a WMI device besides the first one somehow fails to register,
retval is returned while still containing a negative error code. This
causes the ACPI device fail to probe, leaving behind zombie WMI devices
leading to various errors later.

Handle the single error path separately and return 0 unconditionally
after trying to register all WMI devices to solve the issue. Also
continue to register WMI devices even if some fail to allocate memory.

Fixes: 6ee50aaa9a20 ("platform/x86: wmi: Instantiate all devices before adding them")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20231020211005.38216-4-W_Armin@gmx.de
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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platform/x86: wmi: Replace open coded guid_parse_and_compare()

Even though we have no issues in the code, let's replace the open
coded guid_parse_and_compare().

Signed-off-by: Andy Shevchenko <andr

platform/x86: wmi: Replace open coded guid_parse_and_compare()

Even though we have no issues in the code, let's replace the open
coded guid_parse_and_compare().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230621151155.78279-2-andriy.shevchenko@linux.intel.com
Tested-by: Armin Wolf <W_Armin@gmx.de>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: Break possible infinite loop when parsing GUID

The while-loop may break on one of the two conditions, either ID string
is empty or GUID matches. The second one, may never be reach

platform/x86: wmi: Break possible infinite loop when parsing GUID

The while-loop may break on one of the two conditions, either ID string
is empty or GUID matches. The second one, may never be reached if the
parsed string is not correct GUID. In such a case the loop will never
advance to check the next ID.

Break possible infinite loop by factoring out guid_parse_and_compare()
helper which may be moved to the generic header for everyone later on
and preventing from similar mistake in the future.

Interestingly that firstly it appeared when WMI was turned into a bus
driver, but later when duplicated GUIDs were checked, the while-loop
has been replaced by for-loop and hence no mistake made again.

Fixes: a48e23385fcf ("platform/x86: wmi: add context pointer field to struct wmi_device_id")
Fixes: 844af950da94 ("platform/x86: wmi: Turn WMI into a bus driver")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230621151155.78279-1-andriy.shevchenko@linux.intel.com
Tested-by: Armin Wolf <W_Armin@gmx.de>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: Allow retrieving the number of WMI object instances

Currently, the WMI driver core knows how many instances of a given
WMI object exist, but WMI drivers cannot access this informa

platform/x86: wmi: Allow retrieving the number of WMI object instances

Currently, the WMI driver core knows how many instances of a given
WMI object exist, but WMI drivers cannot access this information.
At the same time, some current and upcoming WMI drivers want to
have access to this information. Add wmi_instance_count() and
wmidev_instance_count() to allow WMI drivers to get the number of
WMI object instances.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20230430203153.5587-2-W_Armin@gmx.de
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: Mark GUID-based WMI interface as deprecated

The WMI driver core supports a more mordern bus-based interface for
interacting with WMI devices. The older GUID-based interface depend

platform/x86: wmi: Mark GUID-based WMI interface as deprecated

The WMI driver core supports a more mordern bus-based interface for
interacting with WMI devices. The older GUID-based interface depends
on each WMI GUID and notification id being unique on a given system,
which turned out is not the case.
Mark the older interface as deprecated since new WMI drivers should
use the bus-based interface to avoid this issues.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20230424222939.208137-3-W_Armin@gmx.de
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: Add kernel doc comments

Add kernel doc comments useful for documenting the functions/structs
used to interact with the WMI driver core.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>

platform/x86: wmi: Add kernel doc comments

Add kernel doc comments useful for documenting the functions/structs
used to interact with the WMI driver core.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20230424222939.208137-2-W_Armin@gmx.de
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do e

platform/x86: wmi: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230302144732.1903781-29-u.kleine-koenig@pengutronix.de
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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driver core: make struct bus_type.uevent() take a const *

The uevent() callback in struct bus_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate th

driver core: make struct bus_type.uevent() take a const *

The uevent() callback in struct bus_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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platform/x86: wmi: move dev_to_wblock() and dev_to_wdev to use container_of_const()

The driver core is changing to pass some pointers as const, so move the
dev_to_wdev() and dev_to_wblock() function

platform/x86: wmi: move dev_to_wblock() and dev_to_wdev to use container_of_const()

The driver core is changing to pass some pointers as const, so move the
dev_to_wdev() and dev_to_wblock() functions to use container_of_const()
to handle this change.

Both of these functions now properly keep the const-ness of the pointer
passed into it, while as before it could be lost.

Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Mark Gross <markgross@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-10-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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platform/x86: dell: Add new dell-wmi-ddv driver

The dell-wmi-ddv driver adds support for reading
the current temperature and ePPID of ACPI batteries
on supported Dell machines.

Since the WMI interf

platform/x86: dell: Add new dell-wmi-ddv driver

The dell-wmi-ddv driver adds support for reading
the current temperature and ePPID of ACPI batteries
on supported Dell machines.

Since the WMI interface used by this driver does not
do any input validation and thus cannot be used for probing,
the driver depends on the ACPI battery extension machanism
to discover batteries.

The driver also supports a debugfs interface for retrieving
buffers containing fan and thermal sensor information.
Since the meaing of the content of those buffers is currently
unknown, the interface is meant for reverse-engineering and
will likely be replaced with an hwmon interface once the
meaning has been understood.

The driver was tested on a Dell Inspiron 3505.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220927204521.601887-3-W_Armin@gmx.de
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: Drop forward declaration of static functions

Usually it's not necessary to declare static functions if the symbols are
in the right order. Moving the definition of acpi_wmi_driver

platform/x86: wmi: Drop forward declaration of static functions

Usually it's not necessary to declare static functions if the symbols are
in the right order. Moving the definition of acpi_wmi_driver down in the
compilation unit allows to drop two such declarations.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220919122213.852322-1-u.kleine-koenig@pengutronix.de
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: Allow duplicate GUIDs for drivers that use struct wmi_driver

The WMI subsystem in the kernel currently tracks WMI devices by
a GUID string not by ACPI device. The GUID used by th

platform/x86: wmi: Allow duplicate GUIDs for drivers that use struct wmi_driver

The WMI subsystem in the kernel currently tracks WMI devices by
a GUID string not by ACPI device. The GUID used by the `wmi-bmof`
module however is available from many devices on nearly every machine.

This originally was thought to be a bug, but as it happens on most
machines it is a design mistake. It has been fixed by tying an ACPI
device to the driver with struct wmi_driver. So drivers that have
moved over to struct wmi_driver can actually support multiple
instantiations of a GUID without any problem.

Add an allow list into wmi.c for GUIDs that the drivers that are known
to use struct wmi_driver. The list is populated with `wmi-bmof` right
now. The additional instances of that in sysfs with be suffixed with -%d

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://lore.kernel.org/r/20220829201500.6341-1-mario.limonciello@amd.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: replace usage of found with dedicated list iterator variable

To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use th

platform/x86: wmi: replace usage of found with dedicated list iterator variable

To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable instead of a
found boolean [1].

This removes the need to use a found variable and simply checking if
the variable was set, can determine if the break/goto was hit.

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Link: https://lore.kernel.org/r/20220324072015.62063-1-jakobkoschel@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: Add no_notify_data flag to struct wmi_driver

Some WMI implementations do notifies on WMI objects without a _WED method
allow WMI drivers to indicate that _WED should not be called

platform/x86: wmi: Add no_notify_data flag to struct wmi_driver

Some WMI implementations do notifies on WMI objects without a _WED method
allow WMI drivers to indicate that _WED should not be called for notifies
on the WMI objects the driver is bound to.

Instead the driver's notify callback will simply be called with a NULL
data argument.

Reported-by: Yauhen Kharuzhy <jekhor@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20211128190031.405620-3-hdegoede@redhat.com

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platform/x86: wmi: Fix driver->notify() vs ->probe() race

The driver core sets struct device->driver before calling out
to the bus' probe() method, this leaves a window where an ACPI
notify may happ

platform/x86: wmi: Fix driver->notify() vs ->probe() race

The driver core sets struct device->driver before calling out
to the bus' probe() method, this leaves a window where an ACPI
notify may happen on the WMI object before the driver's
probe() method has completed running, causing e.g. the
driver's notify() callback to get called with drvdata
not yet being set leading to a NULL pointer deref.

At a check for this to the WMI core, ensuring that the notify()
callback is not called before the driver is ready.

Fixes: 1686f5444546 ("platform/x86: wmi: Incorporate acpi_install_notify_handler")
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20211128190031.405620-2-hdegoede@redhat.com

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platform/x86: wmi: Replace read_takes_no_args with a flags field

Replace the wmi_block.read_takes_no_args bool field with
an unsigned long flags field, used together with test_bit()
and friends.

Th

platform/x86: wmi: Replace read_takes_no_args with a flags field

Replace the wmi_block.read_takes_no_args bool field with
an unsigned long flags field, used together with test_bit()
and friends.

This is a preparation patch for fixing a driver->notify() vs ->probe()
race, which requires atomic flag handling.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20211128190031.405620-1-hdegoede@redhat.com

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platform/x86: wmi: change notification handler type

Since AML code on some Xiaomi laptops notifies the WMI hotkey with
0x20 event, we need ACPI_ALL_NOTIFY here to be able to handle it.

Signed-off-b

platform/x86: wmi: change notification handler type

Since AML code on some Xiaomi laptops notifies the WMI hotkey with
0x20 event, we need ACPI_ALL_NOTIFY here to be able to handle it.

Signed-off-by: Mikalai Ramanovich <nikolay.romanovich.00@gmail.com>
Link: https://lore.kernel.org/r/20211015191322.73388-1-nikolay.romanovich.00@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: more detailed error reporting in find_guid()

Make `find_guid()` return an acpi_status, and make it handle NULL
pointer GUID strings; and adapt users accordingly.

Signed-off-by: B

platform/x86: wmi: more detailed error reporting in find_guid()

Make `find_guid()` return an acpi_status, and make it handle NULL
pointer GUID strings; and adapt users accordingly.

Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Link: https://lore.kernel.org/r/20210904175450.156801-31-pobrn@protonmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: introduce helper to retrieve event data

Previously, `acpi_wmi_notify_handler()` and `wmi_get_event_data()`
shared more or less the exact same code to query the data for
a particul

platform/x86: wmi: introduce helper to retrieve event data

Previously, `acpi_wmi_notify_handler()` and `wmi_get_event_data()`
shared more or less the exact same code to query the data for
a particular event.

Introduce a function to get rid of the duplication, and use it
from `acpi_wmi_notify_handler()` and `wmi_get_event_data()`.

Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Link: https://lore.kernel.org/r/20210904175450.156801-30-pobrn@protonmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: introduce helper to determine type

Introduce helper function to determine the appropriate
ACPI type for the input parameter.

This also fixes the following checkpatch warning:
"br

platform/x86: wmi: introduce helper to determine type

Introduce helper function to determine the appropriate
ACPI type for the input parameter.

This also fixes the following checkpatch warning:
"braces {} are not necessary for any arm of this statement".

Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Link: https://lore.kernel.org/r/20210904175450.156801-29-pobrn@protonmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: introduce helper to generate method names

Instead of "manually" constructing the ACPI method name and
hard-coding sizes in WMI functions, introduce a helper method
which generates

platform/x86: wmi: introduce helper to generate method names

Instead of "manually" constructing the ACPI method name and
hard-coding sizes in WMI functions, introduce a helper method
which generates the method name for an arbitrary WMI block.

Furthermore, save the appropriate buffer size into a macro.

Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Link: https://lore.kernel.org/r/20210904175450.156801-28-pobrn@protonmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: introduce helper to convert driver to WMI driver

Introduce a helper function which wraps the appropriate
`container_of()` macro invocation to convert
a `struct device_driver` to `

platform/x86: wmi: introduce helper to convert driver to WMI driver

Introduce a helper function which wraps the appropriate
`container_of()` macro invocation to convert
a `struct device_driver` to `struct wmi_driver`.

Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Link: https://lore.kernel.org/r/20210904175450.156801-27-pobrn@protonmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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platform/x86: wmi: simplify error handling logic

The current code carries out the following ACPI status
mapping:

AE_NOT_FOUND -> AE_OK
AE_OK -> AE_OK
AE_$X -> AE_$X

That is, ev

platform/x86: wmi: simplify error handling logic

The current code carries out the following ACPI status
mapping:

AE_NOT_FOUND -> AE_OK
AE_OK -> AE_OK
AE_$X -> AE_$X

That is, everything is mapped to itself, except AE_NOT_FOUND.
The current code does not do it in the most straighforward way.
Simplify the logic.

Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Link: https://lore.kernel.org/r/20210904175450.156801-26-pobrn@protonmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

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