From patchwork Wed Apr 21 20:47:59 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 12217059 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5A910C43461 for ; Wed, 21 Apr 2021 20:48:41 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1BC0F61445 for ; Wed, 21 Apr 2021 20:48:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1BC0F61445 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EAF3C6E9F6; Wed, 21 Apr 2021 20:48:39 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id 134296E9F0 for ; Wed, 21 Apr 2021 20:48:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1619038117; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=9ClqrLs0VWvbmqd4Kpzdj6bq2wi6fzSArgsNAxBwVl8=; b=Amuhy9Own7Dd2PUrg+OWCjg9SdNYvcwsLuDy9x3/r/DJk6qBOZ/doBzprctrUBJTfcMZmB mc0JxeZTosnnrYFmjflz4bTaNEJr2KYoJMuZG7zR22Y6JwnFu56SaqKV0KJ5Z8k65PHiLQ HaiS6ECepJHA8O//DmNpkbY3xf+h17o= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-395-d9RPrxn2MsqNExTH0Ek5Dg-1; Wed, 21 Apr 2021 16:48:27 -0400 X-MC-Unique: d9RPrxn2MsqNExTH0Ek5Dg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7495818397A6; Wed, 21 Apr 2021 20:48:24 +0000 (UTC) Received: from x1.localdomain (ovpn-112-17.ams2.redhat.com [10.36.112.17]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2D5805D736; Wed, 21 Apr 2021 20:48:21 +0000 (UTC) From: Hans de Goede To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Daniel Vetter , David Airlie , Rajat Jain , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Mark Gross , Andy Shevchenko Date: Wed, 21 Apr 2021 22:47:59 +0200 Message-Id: <20210421204804.589962-5-hdegoede@redhat.com> In-Reply-To: <20210421204804.589962-1-hdegoede@redhat.com> References: <20210421204804.589962-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Subject: [Intel-gfx] [PATCH v2 4/9] drm/privacy-screen: Add notifier support X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Marco Trevisan , Pekka Paalanen , Sebastien Bacher , intel-gfx , dri-devel@lists.freedesktop.org, platform-driver-x86@vger.kernel.org, Mark Pearson , Mario Limonciello Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Add support for privacy-screen consumers to register a notifier to be notified of external (e.g. done by the hw itself on a hotkey press) state changes. Signed-off-by: Hans de Goede --- drivers/gpu/drm/drm_privacy_screen.c | 67 +++++++++++++++++++++++ include/drm/drm_privacy_screen_consumer.h | 15 +++++ include/drm/drm_privacy_screen_driver.h | 4 ++ 3 files changed, 86 insertions(+) diff --git a/drivers/gpu/drm/drm_privacy_screen.c b/drivers/gpu/drm/drm_privacy_screen.c index 294a09194bfb..7a5f878c3171 100644 --- a/drivers/gpu/drm/drm_privacy_screen.c +++ b/drivers/gpu/drm/drm_privacy_screen.c @@ -255,6 +255,49 @@ void drm_privacy_screen_get_state(struct drm_privacy_screen *priv, } EXPORT_SYMBOL(drm_privacy_screen_get_state); +/** + * drm_privacy_screen_register_notifier - register a notifier + * @priv: Privacy screen to register the notifier with + * @nb: Notifier-block for the notifier to register + * + * Register a notifier with the privacy-screen to be notified of changes made + * to the privacy-screen state from outside of the privacy-screen class. + * E.g. the state may be changed by the hardware itself in response to a + * hotkey press. + * + * The notifier is called with no locks held. The new hw_state and sw_state + * can be retrieved using the drm_privacy_screen_get_state() function. + * A pointer to the drm_privacy_screen's struct is passed as the void *data + * argument of the notifier_block's notifier_call. + * + * The notifier will NOT be called when changes are made through + * drm_privacy_screen_set_sw_state(). It is only called for external changes. + * + * Return: 0 on success, negative error code on failure. + */ +int drm_privacy_screen_register_notifier(struct drm_privacy_screen *priv, + struct notifier_block *nb) +{ + return blocking_notifier_chain_register(&priv->notifier_head, nb); +} +EXPORT_SYMBOL(drm_privacy_screen_register_notifier); + +/** + * drm_privacy_screen_unregister_notifier - unregister a notifier + * @priv: Privacy screen to register the notifier with + * @nb: Notifier-block for the notifier to register + * + * Unregister a notifier registered with drm_privacy_screen_register_notifier(). + * + * Return: 0 on success, negative error code on failure. + */ +int drm_privacy_screen_unregister_notifier(struct drm_privacy_screen *priv, + struct notifier_block *nb) +{ + return blocking_notifier_chain_unregister(&priv->notifier_head, nb); +} +EXPORT_SYMBOL(drm_privacy_screen_unregister_notifier); + /*** drm_privacy_screen_driver.h functions ***/ static ssize_t sw_state_show(struct device *dev, @@ -352,6 +395,7 @@ struct drm_privacy_screen *drm_privacy_screen_register( return ERR_PTR(-ENOMEM); mutex_init(&priv->lock); + BLOCKING_INIT_NOTIFIER_HEAD(&priv->notifier_head); priv->dev.class = drm_class; priv->dev.type = &drm_privacy_screen_type; @@ -399,3 +443,26 @@ void drm_privacy_screen_unregister(struct drm_privacy_screen *priv) device_unregister(&priv->dev); } EXPORT_SYMBOL(drm_privacy_screen_unregister); + +/** + * drm_privacy_screen_call_notifier_chain - notify consumers of state change + * @priv: Privacy screen to register the notifier with + * + * A privacy-screen provider driver can call this functions upon external + * changes to the privacy-screen state. E.g. the state may be changed by the + * hardware itself in response to a hotkey press. + * This function must be called without holding the privacy-screen lock. + * the driver must update sw_state and hw_state to reflect the new state before + * calling this function. + * The expected behavior from the driver upon receiving an external state + * change event is: 1. Take the lock; 2. Update sw_state and hw_state; + * 3. Release the lock. 4. Call drm_privacy_screen_call_notifier_chain(). + */ +void drm_privacy_screen_call_notifier_chain(struct drm_privacy_screen *priv) +{ + if (WARN_ON(mutex_is_locked(&priv->lock))) + return; + + blocking_notifier_call_chain(&priv->notifier_head, 0, priv); +} +EXPORT_SYMBOL(drm_privacy_screen_call_notifier_chain); diff --git a/include/drm/drm_privacy_screen_consumer.h b/include/drm/drm_privacy_screen_consumer.h index 941c88b46889..31746a745439 100644 --- a/include/drm/drm_privacy_screen_consumer.h +++ b/include/drm/drm_privacy_screen_consumer.h @@ -24,6 +24,11 @@ int drm_privacy_screen_set_sw_state(struct drm_privacy_screen *priv, void drm_privacy_screen_get_state(struct drm_privacy_screen *priv, enum drm_privacy_screen_status *sw_state_ret, enum drm_privacy_screen_status *hw_state_ret); + +int drm_privacy_screen_register_notifier(struct drm_privacy_screen *priv, + struct notifier_block *nb); +int drm_privacy_screen_unregister_notifier(struct drm_privacy_screen *priv, + struct notifier_block *nb); #else static inline struct drm_privacy_screen *drm_privacy_screen_get(struct device *dev, const char *con_id) @@ -43,6 +48,16 @@ static inline void drm_privacy_screen_get_state(struct drm_privacy_screen *priv, enum drm_privacy_screen_status *hw_state_ret) { } +static inline int drm_privacy_screen_register_notifier(struct drm_privacy_screen *priv, + struct notifier_block *nb) +{ + return -ENODEV; +} +static inline int drm_privacy_screen_unregister_notifier(struct drm_privacy_screen *priv, + struct notifier_block *nb) +{ + return -ENODEV; +} #endif #endif diff --git a/include/drm/drm_privacy_screen_driver.h b/include/drm/drm_privacy_screen_driver.h index 5187ae52eb03..24591b607675 100644 --- a/include/drm/drm_privacy_screen_driver.h +++ b/include/drm/drm_privacy_screen_driver.h @@ -54,6 +54,8 @@ struct drm_privacy_screen { struct mutex lock; /** @list: privacy-screen devices list list-entry. */ struct list_head list; + /** @notifier_head: privacy-screen notifier head. */ + struct blocking_notifier_head notifier_head; /** * @ops: &struct drm_privacy_screen_ops for this privacy-screen. * This is NULL if the driver has unregistered the privacy-screen. @@ -77,4 +79,6 @@ struct drm_privacy_screen *drm_privacy_screen_register( struct device *parent, const struct drm_privacy_screen_ops *ops); void drm_privacy_screen_unregister(struct drm_privacy_screen *priv); +void drm_privacy_screen_call_notifier_chain(struct drm_privacy_screen *priv); + #endif