From nobody Mon Feb 9 16:17:32 2026 Received: from sender4-op-o15.zoho.com (sender4-op-o15.zoho.com [136.143.188.15]) (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 73D38319879; Thu, 13 Nov 2025 19:12:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.15 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763061162; cv=pass; b=HNok5FtRvkzEO46uqmzB7qmuKfG6CgC3sVmQJpouYjmkWGJwmkDBor15t1uW5muefEDIkkhcNG313pURPfGyIlthcoE6YPLQ4abVsBAamwwlV4tgyt1dkOFsmZOeF2TI2cg4+lG97W0hk7Uu6QkITl3jbAKlTe0NbfiF8WvtK9s= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763061162; c=relaxed/simple; bh=5G4eXmI0knMefC6d7JymHvySatAG8ts1cvgOjURPLUU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QAGjRabxIYAP+x5Qx7PhToc8n57kS6N8LJSyjhtQMypB4q3xhNVpPmLmp01htemQVDq2SfeqyksC6xCcgeA4/5oRGDb8/w9Ep29tXTwJhXouH2m20Q4louJnzchY0jsft+Z2NPpVd0RKYZZud8mKa223n2TMXMukFwckfRquRh8= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rong.moe; spf=pass smtp.mailfrom=rong.moe; dkim=pass (1024-bit key) header.d=rong.moe header.i=i@rong.moe header.b=qgGAsLsx; arc=pass smtp.client-ip=136.143.188.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rong.moe Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rong.moe Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=rong.moe header.i=i@rong.moe header.b="qgGAsLsx" ARC-Seal: i=1; a=rsa-sha256; t=1763061138; cv=none; d=zohomail.com; s=zohoarc; b=aRtzGt4se9EIkmpTiyP1E1hS1BD1gc4WRDF9tpo9tdqcb+bUXg2WDRalwUgUCdvZ9qGP9eUacsHKDapxqmsppHQioTRQ2dvH1xnP6mOrzDdyt+5/YzoQ8nnUyGT9/niqT4mYNgMRSpwxt2D99fo5ehT68T5f0d7DsougPKYnjR0= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1763061138; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=/yCofbZk1flUDsswkITJkQvPjMaFSAHMGzBKZQtl+JU=; b=DYbVOKXxwv6FWrKF8/JpZmOSlnTfRPDk32O0lBPvUosvEShYAfRFK2db3/mA3m4l+Wnrr2L9CzFaFFV4FW9AyztAR3Z3C3OjiXWI6ROee78Cdx0Oc/LqLTtUV0MWTdwg/eJ8i/EJFDV3b/CEeks2nK9aB9h8/QcB5nwO58XPSMs= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=rong.moe; spf=pass smtp.mailfrom=i@rong.moe; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1763061138; s=zmail; d=rong.moe; i=i@rong.moe; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-ID:In-Reply-To:References:MIME-Version:Content-Transfer-Encoding:Message-Id:Reply-To; bh=/yCofbZk1flUDsswkITJkQvPjMaFSAHMGzBKZQtl+JU=; b=qgGAsLsxc4URrw0O9+Po16rFa7YMqwmmxhQK0L4reuQsM4IIKGImqQ2TciujU/lT sPwu+ZnXaA4tAJ7YlmjaIEjwN8fU9f3/nazKhVFWVUUxoVaFPJjZrH7mWAGvOOm/WpC dhFH99z7tw2EHPqTtr1zmLNsm6/E6zl4MTbTcyyY= Received: by mx.zohomail.com with SMTPS id 1763061136007799.5474333604368; Thu, 13 Nov 2025 11:12:16 -0800 (PST) From: Rong Zhang To: Mark Pearson , "Derek J. Clark" , Armin Wolf , Hans de Goede , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= Cc: Rong Zhang , Guenter Roeck , platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hwmon@vger.kernel.org Subject: [PATCH v4 6/7] platform/x86: lenovo-wmi-capdata: Wire up Fan Test Data Date: Fri, 14 Nov 2025 03:11:49 +0800 Message-ID: <20251113191152.96076-7-i@rong.moe> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251113191152.96076-1-i@rong.moe> References: <20251113191152.96076-1-i@rong.moe> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMailClient: External Content-Type: text/plain; charset="utf-8" A capdata00 attribute (0x04050000) describes the presence of Fan Test Data. Query it, and bind Fan Test Data as a component of capdata00 accordingly. The component master of capdata00 may pass a callback while binding to retrieve fan info from Fan Test Data. Summarizing this scheme: lenovo-wmi-other <-> capdata00 <-> capdata_fan |- master |- component |- sub-master |- sub-component The callback will be called once both the master and the sub-component are bound to the sub-master (component). This scheme is essential to solve four issues: - The component framework only supports one aggregation per master - A binding is only established until all components are found - The Fan Test Data interface may be missing on some devices - To get rid of queries for the presense of WMI GUIDs Signed-off-by: Rong Zhang --- Changes in v4: - New patch in the series (thanks Armin Wolf's inspiration) - Get rid of wmi_has_guid() (see also [PATCH v4 3/7]) --- drivers/platform/x86/lenovo/wmi-capdata.c | 257 +++++++++++++++++++++- drivers/platform/x86/lenovo/wmi-capdata.h | 19 ++ drivers/platform/x86/lenovo/wmi-other.c | 5 - 3 files changed, 274 insertions(+), 7 deletions(-) diff --git a/drivers/platform/x86/lenovo/wmi-capdata.c b/drivers/platform/x= 86/lenovo/wmi-capdata.c index 8834a2752c97..3c4d1cbbf312 100644 --- a/drivers/platform/x86/lenovo/wmi-capdata.c +++ b/drivers/platform/x86/lenovo/wmi-capdata.c @@ -50,10 +50,17 @@ #define ACPI_AC_CLASS "ac_adapter" #define ACPI_AC_NOTIFY_STATUS 0x80 =20 +#define LWMI_FEATURE_ID_FAN_TEST 0x05 + +#define LWMI_ATTR_ID_FAN_TEST \ + (FIELD_PREP(LWMI_ATTR_DEV_ID_MASK, LWMI_DEVICE_ID_FAN) | \ + FIELD_PREP(LWMI_ATTR_FEAT_ID_MASK, LWMI_FEATURE_ID_FAN_TEST)) + enum lwmi_cd_type { LENOVO_CAPABILITY_DATA_00, LENOVO_CAPABILITY_DATA_01, LENOVO_FAN_TEST_DATA, + CD_TYPE_NONE =3D -1, }; =20 #define LWMI_CD_TABLE_ITEM(_type) \ @@ -75,6 +82,20 @@ struct lwmi_cd_priv { struct notifier_block acpi_nb; /* ACPI events */ struct wmi_device *wdev; struct cd_list *list; + + /* + * A capdata device may be a component master of another capdata device. + * E.g., lenovo-wmi-other <-> capdata00 <-> capdata_fan + * |- master |- component + * |- sub-master + * |- sub-component + */ + struct lwmi_cd_sub_master_priv { + struct device *master_dev; + cd_list_cb_t master_cb; + struct cd_list *sub_component_list; /* ERR_PTR(-ENODEV) implies no sub-c= omponent. */ + bool registered; /* Has the sub-master been registere= d? */ + } *sub_master; }; =20 struct cd_list { @@ -126,7 +147,7 @@ void lwmi_cd_match_add_all(struct device *master, struc= t component_match **match return; =20 for (i =3D 0; i < ARRAY_SIZE(lwmi_cd_table); i++) { - /* Skip optional interfaces. */ + /* Skip sub-components. */ if (lwmi_cd_table[i].type =3D=3D LENOVO_FAN_TEST_DATA) continue; =20 @@ -138,6 +159,56 @@ void lwmi_cd_match_add_all(struct device *master, stru= ct component_match **match } EXPORT_SYMBOL_NS_GPL(lwmi_cd_match_add_all, "LENOVO_WMI_CD"); =20 +/** + * lwmi_cd_call_master_cb() - Call the master callback for the sub-compone= nt. + * @priv: Pointer to the capability data private data. + * + * Call the master callback and pass the sub-component list to it if the + * dependency chain (master <-> sub-master <-> sub-component) is complete. + */ +static void lwmi_cd_call_master_cb(struct lwmi_cd_priv *priv) +{ + struct cd_list *sub_component_list =3D priv->sub_master->sub_component_li= st; + + /* + * Call the callback only if the dependency chain is ready: + * - Binding between master and sub-master: fills master_dev and master_cb + * - Binding between sub-master and sub-component: fills sub_component_li= st + * + * If a binding has been unbound before the other binding is bound, the + * corresponding members filled by the former are guaranteed to be cleare= d. + * + * This function is only called in bind callbacks, and the component + * framework guarantees bind/unbind callbacks may never execute + * simultaneously, which implies that it's impossible to have a race + * condition. + * + * Hence, this check is sufficient to ensure that the callback is called + * at most once and with the correct state, without relying on a specific + * sequence of binding establishment. + */ + if (!sub_component_list || + !priv->sub_master->master_dev || + !priv->sub_master->master_cb) + return; + + if (PTR_ERR(sub_component_list) =3D=3D -ENODEV) + sub_component_list =3D NULL; + else if (WARN_ON(IS_ERR(sub_component_list))) + return; + + priv->sub_master->master_cb(priv->sub_master->master_dev, + sub_component_list); + + /* + * Prevent "unbind and rebind" sequences from userspace from calling the + * callback twice. + */ + priv->sub_master->master_cb =3D NULL; + priv->sub_master->master_dev =3D NULL; + priv->sub_master->sub_component_list =3D NULL; +} + /** * lwmi_cd_component_bind() - Bind component to master device. * @cd_dev: Pointer to the lenovo-wmi-capdata driver parent device. @@ -148,6 +219,8 @@ EXPORT_SYMBOL_NS_GPL(lwmi_cd_match_add_all, "LENOVO_WMI= _CD"); * list. This is used to call lwmi_cd*_get_data to look up attribute data * from the lenovo-wmi-other driver. * + * If cd_dev is a sub-master, try to call the master callback. + * * Return: 0 */ static int lwmi_cd_component_bind(struct device *cd_dev, @@ -159,6 +232,11 @@ static int lwmi_cd_component_bind(struct device *cd_de= v, switch (priv->list->type) { case LENOVO_CAPABILITY_DATA_00: binder->cd00_list =3D priv->list; + + priv->sub_master->master_dev =3D om_dev; + priv->sub_master->master_cb =3D binder->cd_fan_list_cb; + lwmi_cd_call_master_cb(priv); + break; case LENOVO_CAPABILITY_DATA_01: binder->cd01_list =3D priv->list; @@ -170,8 +248,163 @@ static int lwmi_cd_component_bind(struct device *cd_d= ev, return 0; } =20 +/** + * lwmi_cd_component_unbind() - Unbind component to master device. + * @cd_dev: Pointer to the lenovo-wmi-capdata driver parent device. + * @om_dev: Pointer to the lenovo-wmi-other driver parent device. + * @data: Unused. + * + * If cd_dev is a sub-master, clear the collected data from the master dev= ice to + * prevent the binding establishment between the sub-master and the sub- + * component (if it's about to happen) from calling the master callback. + */ +static void lwmi_cd_component_unbind(struct device *cd_dev, + struct device *om_dev, void *data) +{ + struct lwmi_cd_priv *priv =3D dev_get_drvdata(cd_dev); + + switch (priv->list->type) { + case LENOVO_CAPABILITY_DATA_00: + priv->sub_master->master_dev =3D NULL; + priv->sub_master->master_cb =3D NULL; + return; + default: + return; + } +} + static const struct component_ops lwmi_cd_component_ops =3D { .bind =3D lwmi_cd_component_bind, + .unbind =3D lwmi_cd_component_unbind, +}; + +/** + * lwmi_cd_sub_master_bind() - Bind sub-component of sub-master device + * @dev: The sub-master capdata basic device. + * + * Call component_bind_all to bind the sub-component device to the sub-mas= ter + * device. On success, collect the pointer to the sub-component list and t= ry + * to call the master callback. + * + * Return: 0 on success, or an error code. + */ +static int lwmi_cd_sub_master_bind(struct device *dev) +{ + struct lwmi_cd_priv *priv =3D dev_get_drvdata(dev); + struct cd_list *sub_component_list; + int ret; + + ret =3D component_bind_all(dev, &sub_component_list); + if (ret) + return ret; + + priv->sub_master->sub_component_list =3D sub_component_list; + lwmi_cd_call_master_cb(priv); + + return 0; +} + +/** + * lwmi_cd_sub_master_unbind() - Unbind sub-component of sub-master device + * @dev: The sub-master capdata basic device + * + * Clear the collected pointer to the sub-component list to prevent the bi= nding + * establishment between the sub-master and the sub-component (if it's abo= ut to + * happen) from calling the master callback. Then, call component_unbind_a= ll to + * unbind the sub-component device from the sub-master device. + */ +static void lwmi_cd_sub_master_unbind(struct device *dev) +{ + struct lwmi_cd_priv *priv =3D dev_get_drvdata(dev); + + priv->sub_master->sub_component_list =3D NULL; + + component_unbind_all(dev, NULL); +} + +static const struct component_master_ops lwmi_cd_sub_master_ops =3D { + .bind =3D lwmi_cd_sub_master_bind, + .unbind =3D lwmi_cd_sub_master_unbind, +}; + +/** + * lwmi_cd_sub_master_add() - Register a sub-master with its sub-component + * @priv: Pointer to the sub-master capdata device private data. + * @sub_component_type: Type of the sub-component. + * + * Match the sub-component type and register the current capdata device as= a + * sub-master. If the given sub-component type is CD_TYPE_NONE, mark the s= ub- + * component as non-existent without registering sub-master. + * + * Return: 0 on success, or an error code. + */ +static int lwmi_cd_sub_master_add(struct lwmi_cd_priv *priv, + enum lwmi_cd_type sub_component_type) +{ + struct component_match *master_match =3D NULL; + int ret; + + priv->sub_master =3D devm_kzalloc(&priv->wdev->dev, sizeof(*priv->sub_mas= ter), GFP_KERNEL); + if (!priv->sub_master) + return -ENOMEM; + + if (sub_component_type =3D=3D CD_TYPE_NONE) { + /* The master callback will be called with NULL on bind. */ + priv->sub_master->sub_component_list =3D ERR_PTR(-ENODEV); + priv->sub_master->registered =3D false; + return 0; + } + + component_match_add(&priv->wdev->dev, &master_match, + lwmi_cd_match, (void *)sub_component_type); + if (IS_ERR(master_match)) + return PTR_ERR(master_match); + + ret =3D component_master_add_with_match(&priv->wdev->dev, &lwmi_cd_sub_ma= ster_ops, + master_match); + if (ret) + return ret; + + priv->sub_master->registered =3D true; + return 0; +} + +/** + * lwmi_cd_sub_master_del() - Unregister a sub-master if it's registered + * @priv: Pointer to the sub-master capdata device private data. + */ +static void lwmi_cd_sub_master_del(struct lwmi_cd_priv *priv) +{ + if (priv->sub_master->registered) { + component_master_del(&priv->wdev->dev, &lwmi_cd_sub_master_ops); + priv->sub_master->registered =3D false; + } +} + +/** + * lwmi_cd_sub_component_bind() - Bind sub-component to sub-master device. + * @sc_dev: Pointer to the sub-component capdata parent device. + * @sm_dev: Pointer to the sub-master capdata parent device. + * @data: Pointer used to return the capability data list pointer. + * + * On sub-master's bind, provide a pointer to the local capdata list. + * This is used by the sub-master to call the master callback. + * + * Return: 0 + */ +static int lwmi_cd_sub_component_bind(struct device *sc_dev, + struct device *sm_dev, void *data) +{ + struct lwmi_cd_priv *priv =3D dev_get_drvdata(sc_dev); + struct cd_list **listp =3D data; + + *listp =3D priv->list; + + return 0; +} + +static const struct component_ops lwmi_cd_sub_component_ops =3D { + .bind =3D lwmi_cd_sub_component_bind, }; =20 /** @@ -471,9 +704,25 @@ static int lwmi_cd_probe(struct wmi_device *wdev, cons= t void *context) goto out; =20 switch (info->type) { - case LENOVO_CAPABILITY_DATA_00: + case LENOVO_CAPABILITY_DATA_00: { + enum lwmi_cd_type sub_component_type =3D LENOVO_FAN_TEST_DATA; + struct capdata00 capdata00; + + ret =3D lwmi_cd00_get_data(priv->list, LWMI_ATTR_ID_FAN_TEST, &capdata00= ); + if (ret || !(capdata00.supported & LWMI_SUPP_VALID)) { + dev_dbg(&wdev->dev, "capdata00 declares no fan test support\n"); + sub_component_type =3D CD_TYPE_NONE; + } + + /* Sub-master (capdata00) <-> sub-component (capdata_fan) */ + ret =3D lwmi_cd_sub_master_add(priv, sub_component_type); + if (ret) + goto out; + + /* Master (lenovo-wmi-other) <-> sub-master (capdata00) */ ret =3D component_add(&wdev->dev, &lwmi_cd_component_ops); goto out; + } case LENOVO_CAPABILITY_DATA_01: priv->acpi_nb.notifier_call =3D lwmi_cd01_notifier_call; =20 @@ -489,6 +738,7 @@ static int lwmi_cd_probe(struct wmi_device *wdev, const= void *context) ret =3D component_add(&wdev->dev, &lwmi_cd_component_ops); goto out; case LENOVO_FAN_TEST_DATA: + ret =3D component_add(&wdev->dev, &lwmi_cd_sub_component_ops); goto out; default: return -EINVAL; @@ -510,10 +760,13 @@ static void lwmi_cd_remove(struct wmi_device *wdev) =20 switch (priv->list->type) { case LENOVO_CAPABILITY_DATA_00: + lwmi_cd_sub_master_del(priv); + fallthrough; case LENOVO_CAPABILITY_DATA_01: component_del(&wdev->dev, &lwmi_cd_component_ops); break; case LENOVO_FAN_TEST_DATA: + component_del(&wdev->dev, &lwmi_cd_sub_component_ops); break; default: WARN_ON(1); diff --git a/drivers/platform/x86/lenovo/wmi-capdata.h b/drivers/platform/x= 86/lenovo/wmi-capdata.h index 38af4c4e4ef4..0b3bb876d768 100644 --- a/drivers/platform/x86/lenovo/wmi-capdata.h +++ b/drivers/platform/x86/lenovo/wmi-capdata.h @@ -7,6 +7,17 @@ =20 #include =20 +#define LWMI_SUPP_VALID BIT(0) +#define LWMI_SUPP_MAY_GET (LWMI_SUPP_VALID | BIT(1)) +#define LWMI_SUPP_MAY_SET (LWMI_SUPP_VALID | BIT(2)) + +#define LWMI_ATTR_DEV_ID_MASK GENMASK(31, 24) +#define LWMI_ATTR_FEAT_ID_MASK GENMASK(23, 16) +#define LWMI_ATTR_MODE_ID_MASK GENMASK(15, 8) +#define LWMI_ATTR_TYPE_ID_MASK GENMASK(7, 0) + +#define LWMI_DEVICE_ID_FAN 0x04 + struct component_match; struct device; struct cd_list; @@ -32,9 +43,17 @@ struct capdata_fan { u32 max_rpm; }; =20 +typedef void (*cd_list_cb_t)(struct device *master_dev, struct cd_list *cd= _list); + struct lwmi_cd_binder { struct cd_list *cd00_list; struct cd_list *cd01_list; + /* + * May be called during or after the bind callback. + * Will be called with NULL if capdata_fan does not exist. + * The pointer is only valid in the callback; never keep it for later use! + */ + cd_list_cb_t cd_fan_list_cb; }; =20 void lwmi_cd_match_add_all(struct device *master, struct component_match *= *matchptr); diff --git a/drivers/platform/x86/lenovo/wmi-other.c b/drivers/platform/x86= /lenovo/wmi-other.c index f2e1e34d58a9..b3adcc2804fa 100644 --- a/drivers/platform/x86/lenovo/wmi-other.c +++ b/drivers/platform/x86/lenovo/wmi-other.c @@ -54,11 +54,6 @@ #define LWMI_FEATURE_VALUE_GET 17 #define LWMI_FEATURE_VALUE_SET 18 =20 -#define LWMI_ATTR_DEV_ID_MASK GENMASK(31, 24) -#define LWMI_ATTR_FEAT_ID_MASK GENMASK(23, 16) -#define LWMI_ATTR_MODE_ID_MASK GENMASK(15, 8) -#define LWMI_ATTR_TYPE_ID_MASK GENMASK(7, 0) - #define LWMI_OM_FW_ATTR_BASE_PATH "lenovo-wmi-other" =20 static BLOCKING_NOTIFIER_HEAD(om_chain_head); --=20 2.51.0