Re: [PATCH] platform/x86: lenovo: Decouple lenovo-wmi-gamezone and lenovo-wmi-other

[Derek John Clark]

On Fri, Mar 27, 2026 at 8:21 AM Rong Zhang <i@xxxxxxxx> wrote:
>
> Hi Ilpo,
>
> On Fri, 2026-03-27 at 13:25 +0200, Ilpo Järvinen wrote:
> > On Fri, 27 Mar 2026, Rong Zhang wrote:
> >
> > > Currently, lenovo-wmi-gamezone depends on lenovo-wmi-other as the former
> > > imports symbols from the latter. The imported symbols are just used to
> > > register a notifier block. However, there is no runtime dependency
> > > between both drivers, and either of them can run without the other,
> > > which is the major purpose of using the notifier framework.
> > >
> > > Such a link-time dependency is non-optimal. A previous attempt to "fix"
> > > it made LENOVO_WMI_GAMEZONE select LENOVO_WMI_TUNING, which was
> > > fundamentally broken and resulted in undefined Kconfig behavior, as
> > > `select' cannot be used on a symbol with potentially unmet dependencies.
> > >
> > > Decouple both drivers by moving the thermal mode notifier chain to
> > > lenovo-wmi-helpers. Methods for notifier block (un)registration are
> > > exported for lenovo-wmi-gamezone, while a method for querying the
> > > current thermal mode are exported for lenovo-wmi-other.
> > >
> > > This turns the dependency graph from
> > >
> > >             +------------ lenovo-wmi-gamezone
> > >             |                     |
> > >             v                     |
> > >     lenovo-wmi-helpers            |
> > >             ^                     |
> > >             |                     V
> > >             +------------ lenovo-wmi-other
> > >
> > > into
> > >
> > >             +------------ lenovo-wmi-gamezone
> > >             |
> > >             v
> > >     lenovo-wmi-helpers
> > >             ^
> > >             |
> > >             +------------ lenovo-wmi-other
> > >
> > > To make it clear, the name of the notifier chain is also renamed from
> > > `om_chain_head' to `tm_chain_head', indicating that it's used to query
> > > the current thermal mode.
> > >
> > > No functional change intended.
> > >
> > > Fixes: 6e38b9fcbfa3 ("platform/x86: lenovo: gamezone needs "other mode"")
> > > Cc: stable@xxxxxxxxxxxxxxx
> > > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> > > Closes: https://lore.kernel.org/oe-kbuild-all/202603252259.gHvJDyh3-lkp@xxxxxxxxx/
> > > Closes: https://lore.kernel.org/oe-kbuild-all/202603260302.X0NjQOda-lkp@xxxxxxxxx/
> > > Signed-off-by: Rong Zhang <i@xxxxxxxx>
> > > ---
> > >  drivers/platform/x86/lenovo/Kconfig        |   1 -
> > >  drivers/platform/x86/lenovo/wmi-gamezone.c |   4 +-
> > >  drivers/platform/x86/lenovo/wmi-helpers.c  | 102 ++++++++++++++++++++
> > >  drivers/platform/x86/lenovo/wmi-helpers.h  |   8 ++
> > >  drivers/platform/x86/lenovo/wmi-other.c    | 104 +--------------------
> > >  drivers/platform/x86/lenovo/wmi-other.h    |  16 ----
> > >  6 files changed, 113 insertions(+), 122 deletions(-)
> > >  delete mode 100644 drivers/platform/x86/lenovo/wmi-other.h
> > >
> > > diff --git a/drivers/platform/x86/lenovo/Kconfig b/drivers/platform/x86/lenovo/Kconfig
> > > index f885127b007f..09b1b055d2e0 100644
> > > --- a/drivers/platform/x86/lenovo/Kconfig
> > > +++ b/drivers/platform/x86/lenovo/Kconfig
> > > @@ -252,7 +252,6 @@ config LENOVO_WMI_GAMEZONE
> > >     select ACPI_PLATFORM_PROFILE
> > >     select LENOVO_WMI_EVENTS
> > >     select LENOVO_WMI_HELPERS
> > > -   select LENOVO_WMI_TUNING
> > >     help
> > >       Say Y here if you have a WMI aware Lenovo Legion device and would like to use the
> > >       platform-profile firmware interface to manage power usage.
> > > diff --git a/drivers/platform/x86/lenovo/wmi-gamezone.c b/drivers/platform/x86/lenovo/wmi-gamezone.c
> > > index c7fe7e3c9f17..92020225db27 100644
> > > --- a/drivers/platform/x86/lenovo/wmi-gamezone.c
> > > +++ b/drivers/platform/x86/lenovo/wmi-gamezone.c
> > > @@ -23,7 +23,6 @@
> > >  #include "wmi-events.h"
> > >  #include "wmi-gamezone.h"
> > >  #include "wmi-helpers.h"
> > > -#include "wmi-other.h"
> > >
> > >  #define LENOVO_GAMEZONE_GUID "887B54E3-DDDC-4B2C-8B88-68A26A8835D0"
> > >
> > > @@ -383,7 +382,7 @@ static int lwmi_gz_probe(struct wmi_device *wdev, const void *context)
> > >             return ret;
> > >
> > >     priv->mode_nb.notifier_call = lwmi_gz_mode_call;
> > > -   return devm_lwmi_om_register_notifier(&wdev->dev, &priv->mode_nb);
> > > +   return devm_lwmi_tm_register_notifier(&wdev->dev, &priv->mode_nb);
> > >  }
> > >
> > >  static const struct wmi_device_id lwmi_gz_id_table[] = {
> > > @@ -405,7 +404,6 @@ module_wmi_driver(lwmi_gz_driver);
> > >
> > >  MODULE_IMPORT_NS("LENOVO_WMI_EVENTS");
> > >  MODULE_IMPORT_NS("LENOVO_WMI_HELPERS");
> > > -MODULE_IMPORT_NS("LENOVO_WMI_OTHER");
> > >  MODULE_DEVICE_TABLE(wmi, lwmi_gz_id_table);
> > >  MODULE_AUTHOR("Derek J. Clark <derekjohn.clark@xxxxxxxxx>");
> > >  MODULE_DESCRIPTION("Lenovo GameZone WMI Driver");
> > > diff --git a/drivers/platform/x86/lenovo/wmi-helpers.c b/drivers/platform/x86/lenovo/wmi-helpers.c
> > > index 7379defac500..5a88bccb5037 100644
> > > --- a/drivers/platform/x86/lenovo/wmi-helpers.c
> > > +++ b/drivers/platform/x86/lenovo/wmi-helpers.c
> > > @@ -21,11 +21,16 @@
> > >  #include <linux/errno.h>
> > >  #include <linux/export.h>
> > >  #include <linux/module.h>
> > > +#include <linux/notifier.h>
> > >  #include <linux/unaligned.h>
> > >  #include <linux/wmi.h>
> > >
> > > +#include "wmi-gamezone.h"
> > >  #include "wmi-helpers.h"
> > >
> > > +/* Thermal mode notifier chain. */
> > > +static BLOCKING_NOTIFIER_HEAD(tm_chain_head);
> > > +
> > >  /**
> > >   * lwmi_dev_evaluate_int() - Helper function for calling WMI methods that
> > >   * return an integer.
> > > @@ -84,6 +89,103 @@ int lwmi_dev_evaluate_int(struct wmi_device *wdev, u8 instance, u32 method_id,
> > >  };
> > >  EXPORT_SYMBOL_NS_GPL(lwmi_dev_evaluate_int, "LENOVO_WMI_HELPERS");
> > >
> > > +/**
> > > + * lwmi_tm_register_notifier() - Add a notifier to the blocking notifier chain
> > > + * @nb: The notifier_block struct to register
> > > + *
> > > + * Call blocking_notifier_chain_register to register the notifier block to the
> > > + * thermal mode notifier chain.
> > > + *
> > > + * Return: 0 on success, %-EEXIST on error.
> > > + */
> > > +int lwmi_tm_register_notifier(struct notifier_block *nb)
> > > +{
> > > +   return blocking_notifier_chain_register(&tm_chain_head, nb);
> > > +}
> > > +EXPORT_SYMBOL_NS_GPL(lwmi_tm_register_notifier, "LENOVO_WMI_HELPERS");
> > > +
> > > +/**
> > > + * lwmi_tm_unregister_notifier() - Remove a notifier from the blocking notifier
> > > + * chain.
> > > + * @nb: The notifier_block struct to register
> > > + *
> > > + * Call blocking_notifier_chain_unregister to unregister the notifier block from the
> > > + * thermal mode notifier chain.
> > > + *
> > > + * Return: 0 on success, %-ENOENT on error.
> > > + */
> > > +int lwmi_tm_unregister_notifier(struct notifier_block *nb)
> > > +{
> > > +   return blocking_notifier_chain_unregister(&tm_chain_head, nb);
> > > +}
> > > +EXPORT_SYMBOL_NS_GPL(lwmi_tm_unregister_notifier, "LENOVO_WMI_HELPERS");
> > > +
> > > +/**
> > > + * devm_lwmi_tm_unregister_notifier() - Remove a notifier from the blocking
> > > + * notifier chain.
> > > + * @data: Void pointer to the notifier_block struct to register.
> > > + *
> > > + * Call lwmi_tm_unregister_notifier to unregister the notifier block from the
> > > + * thermal mode notifier chain.
> > > + *
> > > + * Return: 0 on success, %-ENOENT on error.
> > > + */
> > > +static void devm_lwmi_tm_unregister_notifier(void *data)
> > > +{
> > > +   struct notifier_block *nb = data;
> > > +
> > > +   lwmi_tm_unregister_notifier(nb);
> > > +}
> > > +
> > > +/**
> > > + * devm_lwmi_tm_register_notifier() - Add a notifier to the blocking notifier
> > > + * chain.
> > > + * @dev: The parent device of the notifier_block struct.
> > > + * @nb: The notifier_block struct to register
> > > + *
> > > + * Call lwmi_tm_register_notifier to register the notifier block to the
> > > + * thermal mode notifier chain. Then add devm_lwmi_tm_unregister_notifier
> > > + * as a device managed action to automatically unregister the notifier block
> > > + * upon parent device removal.
> > > + *
> > > + * Return: 0 on success, or an error code.
> > > + */
> > > +int devm_lwmi_tm_register_notifier(struct device *dev,
> > > +                              struct notifier_block *nb)
> > > +{
> > > +   int ret;
> > > +
> > > +   ret = lwmi_tm_register_notifier(nb);
> > > +   if (ret < 0)
> > > +           return ret;
> > > +
> > > +   return devm_add_action_or_reset(dev, devm_lwmi_tm_unregister_notifier,
> > > +                                   nb);
> > > +}
> > > +EXPORT_SYMBOL_NS_GPL(devm_lwmi_tm_register_notifier, "LENOVO_WMI_HELPERS");
> > > +
> > > +/**
> > > + * lwmi_tm_notifier_call() - Call functions for the notifier call chain.
> > > + * @mode: Pointer to a thermal mode enum to retrieve the data from.
> > > + *
> > > + * Call blocking_notifier_call_chain to retrieve the thermal mode from the
> > > + * lenovo-wmi-gamezone driver.
> > > + *
> > > + * Return: 0 on success, or an error code.
> > > + */
> > > +int lwmi_tm_notifier_call(enum thermal_mode *mode)
> > > +{
> > > +   int ret;
> > > +
> > > +   ret = blocking_notifier_call_chain(&tm_chain_head,
> > > +                                      LWMI_GZ_GET_THERMAL_MODE, &mode);
> > > +   if ((ret & ~NOTIFY_STOP_MASK) != NOTIFY_OK)
> > > +           return -EINVAL;
> > > +
> > > +   return 0;
> > > +}
> > > +EXPORT_SYMBOL_NS_GPL(lwmi_tm_notifier_call, "LENOVO_WMI_HELPERS");
> > > +
> > >  MODULE_AUTHOR("Derek J. Clark <derekjohn.clark@xxxxxxxxx>");
> > >  MODULE_DESCRIPTION("Lenovo WMI Helpers Driver");
> > >  MODULE_LICENSE("GPL");
> > > diff --git a/drivers/platform/x86/lenovo/wmi-helpers.h b/drivers/platform/x86/lenovo/wmi-helpers.h
> > > index 20fd21749803..651a039228ed 100644
> > > --- a/drivers/platform/x86/lenovo/wmi-helpers.h
> > > +++ b/drivers/platform/x86/lenovo/wmi-helpers.h
> > > @@ -7,6 +7,8 @@
> > >
> > >  #include <linux/types.h>
> > >
> > > +struct device;
> > > +struct notifier_block;
> > >  struct wmi_device;
> > >
> > >  struct wmi_method_args_32 {
> > > @@ -17,4 +19,10 @@ struct wmi_method_args_32 {
> > >  int lwmi_dev_evaluate_int(struct wmi_device *wdev, u8 instance, u32 method_id,
> > >                       unsigned char *buf, size_t size, u32 *retval);
> > >
> > > +int lwmi_tm_register_notifier(struct notifier_block *nb);
> > > +int lwmi_tm_unregister_notifier(struct notifier_block *nb);
> > > +int devm_lwmi_tm_register_notifier(struct device *dev,
> > > +                              struct notifier_block *nb);
> > > +int lwmi_tm_notifier_call(enum thermal_mode *mode);
> >
> > This enum is not introduced earlier within this header?
>
> Hmm, no. Declaring a opaque enum earlier should be enough to fix it, as
> wmi-gamezone.h shouldn't be included here. Derek, what do you think?

I think it makes more sense at this point to move everything from
wmi_gamezone.h into wmi_helpers.h. This prevents wmi_capdata.c from
needing to import wmi_gamezone.h, since the thermal mode enum will be
moved (now used by capdata, gamezone, and other). Then the only thing
in the gamezone header would be the gamezone_events_type enum, which
is only used by gamezone and helpers anyway, so that can safely move
and we can delete the entire file. To make that enum name more generic
I'll rename it in the move from gamezone_events_type to
lwmi_event_type (the enum isn't directly referenced anywhere anyway).

If that works for everyone I'll add one more patch to do the move &
cleanup before  "platform/x86: lenovo-wmi-other: Add lwmi_attr_id()
function" where I'm adding the .._NONE thermal mode. That will keep
the purpose of each patch clean and avoid me needing to modify your
patches too much.

Thanks,
Derek.

> Thanks,
> Rong