From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-171.mta0.migadu.com (out-171.mta0.migadu.com [91.218.175.171]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 76187315D3A for ; Fri, 23 Jan 2026 00:20:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.171 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769127643; cv=none; b=d6VWrarRRzSeedgB/+HT1smQncA4RNrGOs/Zi04hiG2NQpHYQrFDHVkGjx44/MiSQ4NQTRdynPYbQn2pKMbhSqjt0bEH4tj2S7disIs9Y9l9LJ7Agmqrqpz1y2CbfI2Cw1rnalCk15nqTzDafxSsqiOIKsXUY1LG0Vi2LUQ0T7U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769127643; c=relaxed/simple; bh=Tr9EMVYx49qmf2vSKEnl56/Ue4O+b0thbtV97HDXBkk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=k8QwmBzzvy0OR+GhqID1xAq58hXfNfQ+2CON7bgQzPqGcDMUzJ39RycQdpfGRw2SKJzqo90sOP/GFhOeftilDvQATZFneHlord5LDf1fWyAKR8BjLN64TYeEEntLz+UQLtA0stD8ZPDTv7ZNR+XyiiM97ME72GyYexYbVgDWlD4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=OyW2GqaR; arc=none smtp.client-ip=91.218.175.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="OyW2GqaR" Message-ID: <8acbc245-a075-462a-a9f1-151e2cba0525@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1769127623; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=DhradW+fKenHR8kuyAeFb7sGPFQMACOA+2Z/cxHiQkg=; b=OyW2GqaRaAvlZvJp/O6oy93GhDICAQtvQHrANuqSosAOmAQu0yfSUx/N95dBvIubt6FcYo YGkQ69LTtJc/wBk4c67bVbW+ME8vvoh7hz56MBYeDtlqXrzf0tL8UHbCue1FckwLACtWby b0Owwv5VwwhhYvPfqrzZEG+PcstJYkg= Date: Fri, 23 Jan 2026 01:20:20 +0100 Precedence: bulk X-Mailing-List: linux-input@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH v12 07/11] platform/x86: asus-wmi: Add support for multiple kbd led handlers To: Antheas Kapenekakis , platform-driver-x86@vger.kernel.org, linux-input@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Jiri Kosina , Benjamin Tissoires , Corentin Chary , "Luke D . Jones" , Hans de Goede , =?UTF-8?Q?Ilpo_J=C3=A4rvinen?= References: <20260122075044.5070-1-lkml@antheas.dev> <20260122075044.5070-8-lkml@antheas.dev> Content-Language: en-US, it-IT, en-US-large X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Denis Benato In-Reply-To: <20260122075044.5070-8-lkml@antheas.dev> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 1/22/26 08:50, Antheas Kapenekakis wrote: > Some devices, such as the Z13 have multiple Aura devices connected > to them by USB. In addition, they might have a WMI interface for > RGB. In Windows, Armoury Crate exposes a unified brightness slider > for all of them, with 3 brightness levels. > > Therefore, to be synergistic in Linux, and support existing tooling > such as UPower, allow adding listeners to the RGB device of the WMI > interface. If WMI does not exist, lazy initialize the interface. > > Since hid-asus and asus-wmi can both interact with the led objects > including from an atomic context, protect the brightness access with a > spinlock and update the values from a workqueue. Use this workqueue to > also process WMI keyboard events, so they are handled asynchronously. Reviewed-by: Denis Benato > Acked-by: Benjamin Tissoires > Signed-off-by: Antheas Kapenekakis > --- > drivers/platform/x86/asus-wmi.c | 183 ++++++++++++++++++--- > include/linux/platform_data/x86/asus-wmi.h | 15 ++ > 2 files changed, 173 insertions(+), 25 deletions(-) > > diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c > index 4aec7ec69250..c45846be3f99 100644 > --- a/drivers/platform/x86/asus-wmi.c > +++ b/drivers/platform/x86/asus-wmi.c > @@ -31,13 +31,13 @@ > #include > #include > #include > -#include > #include > #include > #include > #include > #include > #include > +#include > #include > #include > > @@ -256,6 +256,9 @@ struct asus_wmi { > int tpd_led_wk; > struct led_classdev kbd_led; > int kbd_led_wk; > + bool kbd_led_notify; > + bool kbd_led_avail; > + bool kbd_led_registered; > struct led_classdev lightbar_led; > int lightbar_led_wk; > struct led_classdev micmute_led; > @@ -264,6 +267,7 @@ struct asus_wmi { > struct work_struct tpd_led_work; > struct work_struct wlan_led_work; > struct work_struct lightbar_led_work; > + struct work_struct kbd_led_work; > > struct asus_rfkill wlan; > struct asus_rfkill bluetooth; > @@ -1615,6 +1619,106 @@ static void asus_wmi_battery_exit(struct asus_wmi *asus) > > /* LEDs ***********************************************************************/ > > +struct asus_hid_ref { > + struct list_head listeners; > + struct asus_wmi *asus; > + /* Protects concurrent access from hid-asus and asus-wmi to leds */ > + spinlock_t lock; > +}; > + > +static struct asus_hid_ref asus_ref = { > + .listeners = LIST_HEAD_INIT(asus_ref.listeners), > + .asus = NULL, > + /* > + * Protects .asus, .asus.kbd_led_{wk,notify}, and .listener refs. Other > + * asus variables are read-only after .asus is set. > + * > + * The led cdev device is not protected because it calls backlight_get > + * during initialization, which would result in a nested lock attempt. > + * > + * The led cdev is safe to access without a lock because if > + * kbd_led_avail is true it is initialized before .asus is set and never > + * changed until .asus is dropped. If kbd_led_avail is false, the led > + * cdev is registered by the workqueue, which is single-threaded and > + * cancelled before asus-wmi would access the led cdev to unregister it. > + * > + * A spinlock is used, because the protected variables can be accessed > + * from an IRQ context from asus-hid. > + */ > + .lock = __SPIN_LOCK_UNLOCKED(asus_ref.lock), > +}; > + > +/* > + * Allows registering hid-asus listeners that want to be notified of > + * keyboard backlight changes. > + */ > +int asus_hid_register_listener(struct asus_hid_listener *bdev) > +{ > + struct asus_wmi *asus; > + > + guard(spinlock_irqsave)(&asus_ref.lock); > + list_add_tail(&bdev->list, &asus_ref.listeners); > + asus = asus_ref.asus; > + if (asus) > + queue_work(asus->led_workqueue, &asus->kbd_led_work); > + return 0; > +} > +EXPORT_SYMBOL_GPL(asus_hid_register_listener); > + > +/* > + * Allows unregistering hid-asus listeners that were added with > + * asus_hid_register_listener(). > + */ > +void asus_hid_unregister_listener(struct asus_hid_listener *bdev) > +{ > + guard(spinlock_irqsave)(&asus_ref.lock); > + list_del(&bdev->list); > +} > +EXPORT_SYMBOL_GPL(asus_hid_unregister_listener); > + > +static void do_kbd_led_set(struct led_classdev *led_cdev, int value); > + > +static void kbd_led_update_all(struct work_struct *work) > +{ > + struct asus_wmi *asus; > + bool registered, notify; > + int ret, value; > + > + asus = container_of(work, struct asus_wmi, kbd_led_work); > + > + scoped_guard(spinlock_irqsave, &asus_ref.lock) { > + registered = asus->kbd_led_registered; > + value = asus->kbd_led_wk; > + notify = asus->kbd_led_notify; > + } > + > + if (!registered) { > + /* > + * This workqueue runs under asus-wmi, which means probe has > + * completed and asus-wmi will keep running until it finishes. > + * Therefore, we can safely register the LED without holding > + * a spinlock. > + */ > + ret = devm_led_classdev_register(&asus->platform_device->dev, > + &asus->kbd_led); > + if (!ret) { > + scoped_guard(spinlock_irqsave, &asus_ref.lock) > + asus->kbd_led_registered = true; > + } else { > + pr_warn("Failed to register keyboard backlight LED: %d\n", ret); > + return; > + } > + } > + > + if (value >= 0) > + do_kbd_led_set(&asus->kbd_led, value); > + if (notify) { > + scoped_guard(spinlock_irqsave, &asus_ref.lock) > + asus->kbd_led_notify = false; > + led_classdev_notify_brightness_hw_changed(&asus->kbd_led, value); > + } > +} > + > /* > * These functions actually update the LED's, and are called from a > * workqueue. By doing this as separate work rather than when the LED > @@ -1661,7 +1765,8 @@ static void kbd_led_update(struct asus_wmi *asus) > { > int ctrl_param = 0; > > - ctrl_param = 0x80 | (asus->kbd_led_wk & 0x7F); > + scoped_guard(spinlock_irqsave, &asus_ref.lock) > + ctrl_param = 0x80 | (asus->kbd_led_wk & 0x7F); > asus_wmi_set_devstate(ASUS_WMI_DEVID_KBD_BACKLIGHT, ctrl_param, NULL); > } > > @@ -1694,14 +1799,23 @@ static int kbd_led_read(struct asus_wmi *asus, int *level, int *env) > > static void do_kbd_led_set(struct led_classdev *led_cdev, int value) > { > + struct asus_hid_listener *listener; > struct asus_wmi *asus; > int max_level; > > asus = container_of(led_cdev, struct asus_wmi, kbd_led); > max_level = asus->kbd_led.max_brightness; > > - asus->kbd_led_wk = clamp_val(value, 0, max_level); > - kbd_led_update(asus); > + scoped_guard(spinlock_irqsave, &asus_ref.lock) > + asus->kbd_led_wk = clamp_val(value, 0, max_level); > + > + if (asus->kbd_led_avail) > + kbd_led_update(asus); > + > + scoped_guard(spinlock_irqsave, &asus_ref.lock) { > + list_for_each_entry(listener, &asus_ref.listeners, list) > + listener->brightness_set(listener, asus->kbd_led_wk); > + } > } > > static int kbd_led_set(struct led_classdev *led_cdev, enum led_brightness value) > @@ -1716,10 +1830,11 @@ static int kbd_led_set(struct led_classdev *led_cdev, enum led_brightness value) > > static void kbd_led_set_by_kbd(struct asus_wmi *asus, enum led_brightness value) > { > - struct led_classdev *led_cdev = &asus->kbd_led; > - > - do_kbd_led_set(led_cdev, value); > - led_classdev_notify_brightness_hw_changed(led_cdev, asus->kbd_led_wk); > + scoped_guard(spinlock_irqsave, &asus_ref.lock) { > + asus->kbd_led_wk = value; > + asus->kbd_led_notify = true; > + } > + queue_work(asus->led_workqueue, &asus->kbd_led_work); > } > > static enum led_brightness kbd_led_get(struct led_classdev *led_cdev) > @@ -1729,10 +1844,18 @@ static enum led_brightness kbd_led_get(struct led_classdev *led_cdev) > > asus = container_of(led_cdev, struct asus_wmi, kbd_led); > > + scoped_guard(spinlock_irqsave, &asus_ref.lock) { > + if (!asus->kbd_led_avail) > + return asus->kbd_led_wk; > + } > + > retval = kbd_led_read(asus, &value, NULL); > if (retval < 0) > return retval; > > + scoped_guard(spinlock_irqsave, &asus_ref.lock) > + asus->kbd_led_wk = value; > + > return value; > } > > @@ -1844,7 +1967,9 @@ static int camera_led_set(struct led_classdev *led_cdev, > > static void asus_wmi_led_exit(struct asus_wmi *asus) > { > - led_classdev_unregister(&asus->kbd_led); > + scoped_guard(spinlock_irqsave, &asus_ref.lock) > + asus_ref.asus = NULL; > + > led_classdev_unregister(&asus->tpd_led); > led_classdev_unregister(&asus->wlan_led); > led_classdev_unregister(&asus->lightbar_led); > @@ -1882,22 +2007,26 @@ static int asus_wmi_led_init(struct asus_wmi *asus) > goto error; > } > > - if (!kbd_led_read(asus, &led_val, NULL) && !dmi_check_system(asus_use_hid_led_dmi_ids)) { > - pr_info("using asus-wmi for asus::kbd_backlight\n"); > - asus->kbd_led_wk = led_val; > - asus->kbd_led.name = "asus::kbd_backlight"; > - asus->kbd_led.flags = LED_BRIGHT_HW_CHANGED; > - asus->kbd_led.brightness_set_blocking = kbd_led_set; > - asus->kbd_led.brightness_get = kbd_led_get; > - asus->kbd_led.max_brightness = 3; > + asus->kbd_led.name = "asus::kbd_backlight"; > + asus->kbd_led.flags = LED_BRIGHT_HW_CHANGED; > + asus->kbd_led.brightness_set_blocking = kbd_led_set; > + asus->kbd_led.brightness_get = kbd_led_get; > + asus->kbd_led.max_brightness = 3; > + asus->kbd_led_avail = !kbd_led_read(asus, &led_val, NULL); > + INIT_WORK(&asus->kbd_led_work, kbd_led_update_all); > > + if (asus->kbd_led_avail) { > + asus->kbd_led_wk = led_val; > if (num_rgb_groups != 0) > asus->kbd_led.groups = kbd_rgb_mode_groups; > + } else { > + asus->kbd_led_wk = -1; > + } > > - rv = led_classdev_register(&asus->platform_device->dev, > - &asus->kbd_led); > - if (rv) > - goto error; > + scoped_guard(spinlock_irqsave, &asus_ref.lock) { > + asus_ref.asus = asus; > + if (asus->kbd_led_avail || !list_empty(&asus_ref.listeners)) > + queue_work(asus->led_workqueue, &asus->kbd_led_work); > } > > if (asus_wmi_dev_is_present(asus, ASUS_WMI_DEVID_WIRELESS_LED) > @@ -4372,6 +4501,7 @@ static int asus_wmi_get_event_code(union acpi_object *obj) > > static void asus_wmi_handle_event_code(int code, struct asus_wmi *asus) > { > + enum led_brightness led_value; > unsigned int key_value = 1; > bool autorelease = 1; > > @@ -4388,19 +4518,22 @@ static void asus_wmi_handle_event_code(int code, struct asus_wmi *asus) > return; > } > > + scoped_guard(spinlock_irqsave, &asus_ref.lock) > + led_value = asus->kbd_led_wk; > + > if (code == NOTIFY_KBD_BRTUP) { > - kbd_led_set_by_kbd(asus, asus->kbd_led_wk + 1); > + kbd_led_set_by_kbd(asus, led_value + 1); > return; > } > if (code == NOTIFY_KBD_BRTDWN) { > - kbd_led_set_by_kbd(asus, asus->kbd_led_wk - 1); > + kbd_led_set_by_kbd(asus, led_value - 1); > return; > } > if (code == NOTIFY_KBD_BRTTOGGLE) { > - if (asus->kbd_led_wk == asus->kbd_led.max_brightness) > + if (led_value >= asus->kbd_led.max_brightness) > kbd_led_set_by_kbd(asus, 0); > else > - kbd_led_set_by_kbd(asus, asus->kbd_led_wk + 1); > + kbd_led_set_by_kbd(asus, led_value + 1); > return; > } > > diff --git a/include/linux/platform_data/x86/asus-wmi.h b/include/linux/platform_data/x86/asus-wmi.h > index 419491d4abca..d347cffd05d5 100644 > --- a/include/linux/platform_data/x86/asus-wmi.h > +++ b/include/linux/platform_data/x86/asus-wmi.h > @@ -172,12 +172,20 @@ enum asus_ally_mcu_hack { > ASUS_WMI_ALLY_MCU_HACK_DISABLED, > }; > > +/* Used to notify hid-asus when asus-wmi changes keyboard backlight */ > +struct asus_hid_listener { > + struct list_head list; > + void (*brightness_set)(struct asus_hid_listener *listener, int brightness); > +}; > + > #if IS_REACHABLE(CONFIG_ASUS_WMI) > void set_ally_mcu_hack(enum asus_ally_mcu_hack status); > void set_ally_mcu_powersave(bool enabled); > int asus_wmi_get_devstate_dsts(u32 dev_id, u32 *retval); > int asus_wmi_set_devstate(u32 dev_id, u32 ctrl_param, u32 *retval); > int asus_wmi_evaluate_method(u32 method_id, u32 arg0, u32 arg1, u32 *retval); > +int asus_hid_register_listener(struct asus_hid_listener *cdev); > +void asus_hid_unregister_listener(struct asus_hid_listener *cdev); > #else > static inline void set_ally_mcu_hack(enum asus_ally_mcu_hack status) > { > @@ -198,6 +206,13 @@ static inline int asus_wmi_evaluate_method(u32 method_id, u32 arg0, u32 arg1, > { > return -ENODEV; > } > +static inline int asus_hid_register_listener(struct asus_hid_listener *bdev) > +{ > + return -ENODEV; > +} > +static inline void asus_hid_unregister_listener(struct asus_hid_listener *bdev) > +{ > +} > #endif > > #endif /* __PLATFORM_DATA_X86_ASUS_WMI_H */