From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.14]) (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 4D0C33EDADB; Thu, 28 May 2026 12:29:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.14 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779971384; cv=none; b=QcniALnsWIY13/C9V6vLJIE9obFaDXqPHQy7HsMv1HCWCDa9VaYO45gNvH10k8RlIqoQyab4559z8fhf4T9WcLyZ3IWSzwAm1IBtb8ZJE0gXy8v/tS2L8nIkPf9eEQvNXXQLfh+81hpuQCHms/xnn+tYSCf3ZlqykbP5N+Q/X/8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779971384; c=relaxed/simple; bh=fxf2cgq2PsGocI/zR49LK5z6PKUKrsIsb/kTGVXoiqs=; h=From:Date:To:cc:Subject:In-Reply-To:Message-ID:References: MIME-Version:Content-Type; b=ZzFY81tGMmg+Rp5qkPfRfGnzbVaVXKu2ok2TxrAYBFC86HMsLqNXJN4ECFNfRfuz+TIFEU2HT3D3FOqph7phKZSipJUIDBpFuiQ+jcjPAV6utQtLWdS3vEUQQ3HgeYTVefXxh9sEWyDm/BLFvoE9jvKzes993iH8mr1+Ip+ZNDk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=NqttBmwV; arc=none smtp.client-ip=198.175.65.14 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="NqttBmwV" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1779971381; x=1811507381; h=from:date:to:cc:subject:in-reply-to:message-id: references:mime-version; bh=fxf2cgq2PsGocI/zR49LK5z6PKUKrsIsb/kTGVXoiqs=; b=NqttBmwVwiyHRKz1O775Ku10p4uvoVVgS3QlI1TwF0QCYhUl0xIZYRoG GPmdum970nWcCixttwaPcv0HbTinQzp2iUAH6ZTmPXjCBEZpnWrRaKq7E /5uWge5bs6vwlPFFYa39EJneGuw3lUvZ9Sd5BFE9oQhzsPAslgONcCzWM MJgUi5dbjQarXuxSKJ50S4/g4mlThv1ysRZQ0a/nwzcfwR04JFK7TQS/D 8cuWxNNZdI4CxbFZRD2wcGzpMOjjxRmGf7aPJlZLR1MZbGNSd2U8UpxMQ E9weginlNM1wshbE6PXjerDruDLkvdYWI/0hv/bSXr5B/8wLWEI5aoJF8 A==; X-CSE-ConnectionGUID: D4MsKresS2OUxaNXhapNSQ== X-CSE-MsgGUID: zaVeusFaSxiUj8AJg98DQw== X-IronPort-AV: E=McAfee;i="6800,10657,11799"; a="84700423" X-IronPort-AV: E=Sophos;i="6.24,173,1774335600"; d="scan'208";a="84700423" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 May 2026 05:29:40 -0700 X-CSE-ConnectionGUID: tV2h0scuRFCP1C8NLX7KAw== X-CSE-MsgGUID: NzmW9OKMTTaROCfYZyg0xg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.24,173,1774335600"; d="scan'208";a="239526271" Received: from ijarvine-mobl1.ger.corp.intel.com (HELO localhost) ([10.245.245.187]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 May 2026 05:29:37 -0700 From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= Date: Thu, 28 May 2026 15:29:33 +0300 (EEST) To: "Yo-Jung Leo Lin (AMD)" cc: Hans de Goede , "Mario Limonciello (AMD)" , LKML , platform-driver-x86@vger.kernel.org, Shyam Sundar S K , Armin Wolf Subject: Re: [PATCH v5] platform/x86/amd: Introduce Halo Box RGB LED driver In-Reply-To: <20260523-halo-leds-v2-plus-v5-1-497dc9719a18@amd.com> Message-ID: References: <20260523-halo-leds-v2-plus-v5-1-497dc9719a18@amd.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII On Sat, 23 May 2026, Yo-Jung Leo Lin (AMD) wrote: > The Halo Box features an RGB LED light bar that can be controlled > through WMI methods to display any color combination. > > The driver exposes the LED through the LED multicolor subsystem, > allowing userspace to control RGB values via sysfs: > /sys/class/leds/amd_halo:multicolor:status/multi_intensity > /sys/class/leds/amd_halo:multicolor:status/brightness > > Hardware interface: > - Three separate RGB channels (Red, Green, Blue) > - All 3 channels are configured at once with a single WMI method call > - Value range: 0-100 (matching hardware range directly) > > Co-developed-by: Mario Limonciello (AMD) > Signed-off-by: Mario Limonciello (AMD) > Reviewed-by: Shyam Sundar S K > Reviewed-by: Armin Wolf > Signed-off-by: Yo-Jung Leo Lin (AMD) This seems mostly okay, there are a few minor things still to address marked below. > --- > v4 -> v5 > No code chang. Only email etiquette fixes > - Fix the "From: " in the mail from leo.lin@amd.com to Leo.Lin@amd.com, > so that it matches s-o-b > - Pull the Reviewed-by trailer from previous threads. > - Link to v4: https://lore.kernel.org/r/20260521-halo-leds-v2-plus-v4-1-b498bbab36a2@amd.com > > v3 -> v4 > There's a new WMI method we introduced in BIOS for color setting, to > replace the original ones, so in this version: > - Introduce a new "AMD_HALO_WMI_RGB" method ID. This WMI method takes 1 > command argument (GET/SET) and 3 RGB values. This method is capable of > turning on and setting all RGB channels at once in a single call, reducing > some undesirable visual effects when setting them separately. > - Replace color setting code with this new "AMD_HALO_WMI_RGB" method. > - Remove implementations of unused WMI methods. > > This version also fixes things pointed out in the previous version: > - Explicltly specify the endianess of WMI arguments as __le32, and use > endian-conversion helpers accordingly. > - Use scope-based cleanup helper for WMI buffer. > - Remove cleanup for channel setting WMI in probe. > - Explicitly include headers for kfree and le16_to_cpu > - Fix white spaces > - Fix designated initializor style > - Link to v3: https://lore.kernel.org/r/20260508-halo-leds-v2-plus-v3-1-91df458966ea@amd.com > > (Didn't pull Shyam's Reviewed-by because this is a relatively bigger change.) > > v2 -> v3: > - Re-introduce OF/OFF method: implement them with wmidev_invoke_method > - Explicitly call the ON method on brightness_set callback for > brightness != 0; call the OFF method when brightness == 0 > - Turn off light bar if TURN_ON/SET_LIGHTBAR can't function normally > - Replace get_unaligned_le64 with casting and le16_to_cpu() > - Add an inline function (wmi_status_to_err) to convert WMI return > values to errno > - Use amd_halo_wmi_set_channel in probe to set default color > - Use devm_mutex_init() instead > - Remove unused includes > - Link to v2: https://lore.kernel.org/r/20260504-halo-leds-v2-plus-v2-1-af027727605b@amd.com > > v1 -> v2: > - Fix Kconfig dependencies > - Remove amd_halo_wmi_turn_off(). Handle the case where brightness=0 with the > same logic where brightness != 0 > - Remove the brightness_get callback, because currently there isn't a > well-defined global bightness in hardware. Note that the sysfs brightness > stil works. It just caches the value last set. > - Convert to wmidev_invoke_method() > - Convert to ARRAY_SIZE() > - Convert some macros to enum > - Convert to devm_led_classdev_multicolor_register_ext() > - Rename sysfs path to amd_halo:multicolor:status > - Fold default LED colors setting in probe, before registration > - Add no_singleton option > - Make default RGB values into macros and adjust their values > --- > MAINTAINERS | 7 + > drivers/platform/x86/amd/Kconfig | 11 ++ > drivers/platform/x86/amd/Makefile | 1 + > drivers/platform/x86/amd/amd_halo_led.c | 267 ++++++++++++++++++++++++++++++++ > 4 files changed, 286 insertions(+) > > diff --git a/MAINTAINERS b/MAINTAINERS > index 8063cb56feef..cde3865addb4 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -1138,6 +1138,13 @@ F: drivers/char/hw_random/geode-rng.c > F: drivers/crypto/geode* > F: drivers/video/fbdev/geode/ > > +AMD HALO BOX RGB LED DRIVER > +M: Mario Limonciello (AMD) > +R: Yo-Jung Leo Lin (AMD) > +L: platform-driver-x86@vger.kernel.org > +S: Supported > +F: drivers/platform/x86/amd/amd_halo_led.c > + > AMD HSMP DRIVER > M: Naveen Krishna Chatradhi > R: Carlos Bilbao > diff --git a/drivers/platform/x86/amd/Kconfig b/drivers/platform/x86/amd/Kconfig > index b813f9265368..a1a74ef6c859 100644 > --- a/drivers/platform/x86/amd/Kconfig > +++ b/drivers/platform/x86/amd/Kconfig > @@ -34,6 +34,17 @@ config AMD_WBRF > This mechanism will only be activated on platforms that advertise a > need for it. > > +config AMD_HALO_LED > + tristate "AMD Halo Box RGB LED Driver" > + depends on ACPI_WMI && LEDS_CLASS_MULTICOLOR > + help > + This driver provides RGB LED control for AMD Halo Box devices > + through the LED multicolor subsystem. The Halo Box light bar can > + be controlled via sysfs to display any RGB color combination. > + > + To compile this driver as a module, choose M here: the module > + will be called amd_halo_led. > + > config AMD_ISP_PLATFORM > tristate "AMD ISP4 platform driver" > depends on I2C && X86_64 && ACPI > diff --git a/drivers/platform/x86/amd/Makefile b/drivers/platform/x86/amd/Makefile > index f6ff0c837f34..2f467dbbfc8a 100644 > --- a/drivers/platform/x86/amd/Makefile > +++ b/drivers/platform/x86/amd/Makefile > @@ -10,5 +10,6 @@ obj-$(CONFIG_AMD_PMC) += pmc/ > obj-$(CONFIG_AMD_HSMP) += hsmp/ > obj-$(CONFIG_AMD_PMF) += pmf/ > obj-$(CONFIG_AMD_WBRF) += wbrf.o > +obj-$(CONFIG_AMD_HALO_LED) += amd_halo_led.o > obj-$(CONFIG_AMD_ISP_PLATFORM) += amd_isp4.o > obj-$(CONFIG_AMD_HFI) += hfi/ > diff --git a/drivers/platform/x86/amd/amd_halo_led.c b/drivers/platform/x86/amd/amd_halo_led.c > new file mode 100644 > index 000000000000..f9ee6368f8ea > --- /dev/null > +++ b/drivers/platform/x86/amd/amd_halo_led.c > @@ -0,0 +1,267 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * AMD Halo Box RGB LED Driver > + * > + * Copyright (C) 2026 Advanced Micro Devices, Inc. > + * > + * This driver provides RGB LED control for AMD Halo Box devices through > + * the LED multicolor subsystem. The Halo Box light bar can be controlled > + * via sysfs to display any RGB color combination. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include These must be in alphabetical order. Put the byteorder one into a separate group separated with a blank line. > + > +#define AMD_HALO_GUID "081E747B-E028-4232-AF24-EAAEAB2B1E86" > + > +/* WMI method IDs from MOF */ > +enum { > + AMD_HALO_WMI_TURN_OFF = 0x04, > + AMD_HALO_WMI_RGB = 0x07 > +}; > + > +/* Arg0 of the AMD_HALO_WMI_RGB Method */ > +enum { > + AMD_HALO_RGB_CMD_GET, > + AMD_HALO_RGB_CMD_SET > +}; > + > +/* Status codes from spec */ > +#define AMD_HALO_STATUS_SUCCESS 0x0000 > +#define AMD_HALO_STATUS_INVALID_PARAM 0xFFFD > + > +/* Brightness uses 0-100 range */ > +#define AMD_HALO_MAX_HW_BRIGHTNESS 100 > + > +/* Default RGB brightness */ > +#define AMD_HALO_DEFAULT_RED 50 > +#define AMD_HALO_DEFAULT_GREEN 30 > +#define AMD_HALO_DEFAULT_BLUE 30 > + > +/** > + * struct amd_halo_led_data - Driver private data > + * @wdev: WMI device pointer > + * @led_mc: LED multicolor class device > + * @subled_info: RGB channel information > + * @lock: Mutex to protect WMI calls > + */ > +struct amd_halo_led_data { > + struct wmi_device *wdev; > + struct led_classdev_mc led_mc; > + struct mc_subled subled_info[3]; > + struct mutex lock; /* Protects WMI method calls */ > +}; > + > +struct amd_halo_wmi_args { > + __le32 arg0; > + __le32 arg1; Please add types.h > +}; > + > +struct amd_halo_wmi_args_rgb { > + __le32 cmd; > + __le32 red; > + __le32 green; > + __le32 blue; > +}; > + > +static inline int wmi_status_to_err(u16 status) > +{ > + switch (status) { > + case AMD_HALO_STATUS_SUCCESS: > + return 0; > + case AMD_HALO_STATUS_INVALID_PARAM: > + return -EINVAL; > + default: > + return -EIO; > + } > +} > + > +static int __amd_halo_wmi_call(struct wmi_device *wdev, > + u32 method_id, void *data, size_t length) > +{ > + struct wmi_buffer input = { > + .length = length, > + .data = data, > + }; > + __le16 *result_status __free(kfree) = NULL; > + struct wmi_buffer output = {}; > + int ret; > + > + ret = wmidev_invoke_method(wdev, 0, method_id, > + &input, &output, sizeof(*result_status)); > + if (ret) > + return ret; > + > + /* Return buffer per spec: Bytes[0:1] = Status (little-endian) */ > + result_status = output.data; Please move the variable declaration here (mid-function) as explained in the long comment in cleanup.h. > + ret = wmi_status_to_err(le16_to_cpu(*result_status)); > + > + return ret; return wmi_status_to_err(...); > +} > + > +/** > + * amd_halo_wmi_turn_off - Turn off all LED channels > + * @wdev: WMI device pointer > + * > + * Return: 0 on success, negative error code on failure > + */ > +static int amd_halo_wmi_turn_off(struct wmi_device *wdev) > +{ > + struct amd_halo_wmi_args args = { }; > + > + return __amd_halo_wmi_call(wdev, AMD_HALO_WMI_TURN_OFF, &args, sizeof(args)); > +} > + > +/** > + * amd_halo_wmi_set_rgb - Set all RGB channels atomically > + * @wdev: WMI device pointer > + * @r: brightness for red channel (0 - 100) > + * @g: brightness for green channel (0 - 100) > + * @b: brightness for blue channel (0 - 100) > + * > + * Return: 0 on success, negative error code on failure > + */ > +static int amd_halo_wmi_set_rgb(struct wmi_device *wdev, u32 r, u32 g, u32 b) > +{ > + if (r > AMD_HALO_MAX_HW_BRIGHTNESS || > + g > AMD_HALO_MAX_HW_BRIGHTNESS || > + b > AMD_HALO_MAX_HW_BRIGHTNESS) { > + return -EINVAL; > + } > + > + struct amd_halo_wmi_args_rgb args = { > + .cmd = cpu_to_le32(AMD_HALO_RGB_CMD_SET), > + .red = cpu_to_le32(r), > + .green = cpu_to_le32(g), > + .blue = cpu_to_le32(b) Add the trailing comma. > + }; > + > + return __amd_halo_wmi_call(wdev, AMD_HALO_WMI_RGB, &args, sizeof(args)); > +} > + > +/** > + * amd_halo_brightness_set - Set LED brightness and color > + * @cdev: LED class device > + * @brightness: Brightness value > + * > + * Return: 0 on success, negative error code on failure > + */ > +static int amd_halo_brightness_set(struct led_classdev *cdev, > + enum led_brightness brightness) > +{ > + struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev); > + struct amd_halo_led_data *data = container_of(mc_cdev, Add container_of.h > + struct amd_halo_led_data, > + led_mc); > + u32 red_hw, green_hw, blue_hw; > + int ret; > + > + guard(mutex)(&data->lock); > + > + led_mc_calc_color_components(mc_cdev, brightness); > + > + if (brightness == 0) > + return amd_halo_wmi_turn_off(data->wdev); > + > + red_hw = mc_cdev->subled_info[0].brightness; > + green_hw = mc_cdev->subled_info[1].brightness; > + blue_hw = mc_cdev->subled_info[2].brightness; > + > + ret = amd_halo_wmi_set_rgb(data->wdev, red_hw, green_hw, blue_hw); > + if (ret) > + goto out; > + > + return 0; > + > +out: > + /* > + * Consider the light bar non-functional if AMD_HALO_WMI_RGB failed. > + * Attempt to turn the LED off completely as clean-up. > + */ > + if (amd_halo_wmi_turn_off(data->wdev)) > + dev_warn_ratelimited(&data->wdev->dev, "Failed to turn LED off on cleanup\n"); Please add include for this. > + > + return ret; > +} > + > +/** > + * amd_halo_probe - Driver probe function > + * @wdev: WMI device > + * @context: Context data (unused) > + * > + * Return: 0 on success, negative error code on failure > + */ > +static int amd_halo_probe(struct wmi_device *wdev, const void *context) > +{ > + struct led_init_data led_init_data = { > + .devicename = "amd_halo", > + .default_label = "multicolor:" LED_FUNCTION_STATUS, > + .devname_mandatory = true, > + }; > + struct amd_halo_led_data *data; > + int ret; > + > + data = devm_kzalloc(&wdev->dev, sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + ret = devm_mutex_init(&wdev->dev, &data->lock); > + if (ret) > + return ret; > + > + data->wdev = wdev; > + dev_set_drvdata(&wdev->dev, data); > + > + data->subled_info[0].color_index = LED_COLOR_ID_RED; > + data->subled_info[1].color_index = LED_COLOR_ID_GREEN; > + data->subled_info[2].color_index = LED_COLOR_ID_BLUE; > + data->subled_info[0].intensity = AMD_HALO_DEFAULT_RED; > + data->subled_info[1].intensity = AMD_HALO_DEFAULT_GREEN; > + data->subled_info[2].intensity = AMD_HALO_DEFAULT_BLUE; > + > + data->led_mc.led_cdev.brightness = AMD_HALO_MAX_HW_BRIGHTNESS; > + data->led_mc.led_cdev.max_brightness = AMD_HALO_MAX_HW_BRIGHTNESS; > + data->led_mc.led_cdev.brightness_set_blocking = amd_halo_brightness_set; > + data->led_mc.led_cdev.flags = LED_CORE_SUSPENDRESUME | LED_RETAIN_AT_SHUTDOWN; > + data->led_mc.num_colors = ARRAY_SIZE(data->subled_info); Add include. > + data->led_mc.subled_info = data->subled_info; > + > + ret = amd_halo_wmi_set_rgb(wdev, AMD_HALO_DEFAULT_RED, AMD_HALO_DEFAULT_GREEN, > + AMD_HALO_DEFAULT_BLUE); > + if (ret) > + return ret; > + > + ret = devm_led_classdev_multicolor_register_ext(&wdev->dev, &data->led_mc, > + &led_init_data); > + if (ret) > + return dev_err_probe(&wdev->dev, ret, > + "Failed to register multicolor LED\n"); > + return 0; > +} > + > +static const struct wmi_device_id amd_halo_id_table[] = { > + { .guid_string = AMD_HALO_GUID }, > + { } > +}; > +MODULE_DEVICE_TABLE(wmi, amd_halo_id_table); > + > +static struct wmi_driver amd_halo_driver = { > + .driver = { > + .name = "amd_halo_led", > + }, > + .id_table = amd_halo_id_table, > + .probe = amd_halo_probe, > + .no_singleton = true, > +}; > + > +module_wmi_driver(amd_halo_driver); > + > +MODULE_AUTHOR("Mario Limonciello (AMD) "); > +MODULE_AUTHOR("Yo-Jung Leo Lin (AMD) "); > +MODULE_DESCRIPTION("AMD Halo Box RGB LED Control Driver"); > +MODULE_LICENSE("GPL"); > > --- > base-commit: 687da68900cd1a46549f7d9430c7d40346cb86a0 > change-id: 20260429-halo-leds-v2-plus-722c8083afe8 > > Best regards, > -- i.