From patchwork Wed Apr 14 15:10:44 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: 12203147 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 autolearn=ham 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 313FFC433ED for ; Wed, 14 Apr 2021 15:11:20 +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 CEF5361155 for ; Wed, 14 Apr 2021 15:11:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CEF5361155 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 5E6256E938; Wed, 14 Apr 2021 15:11:19 +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 14AB56E925 for ; Wed, 14 Apr 2021 15:11:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1618413077; 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=2rCvR3udWAuN8iEY7ESeyVC+bz59iWOoCws88KJ9dTE=; b=h5Ln7tcIqV+FiKpJ8KBsyGkxb8/Y/bRoN2ydWAmPjy1XT5hZPmgIgkl7XqeAXyluEFyph2 ZY+m60+khwkpzeAVRkvzKcDupAZB9ZxdkaIAECqK0txtK5qoqQp1EqmQsiOW/OwsgpO+73 1F5Tz3MhsBOWJJWH/7yYaadZyFZ8zmY= 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-227-olHOEYDtMPi3DF4VL6Es_g-1; Wed, 14 Apr 2021 11:11:13 -0400 X-MC-Unique: olHOEYDtMPi3DF4VL6Es_g-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 D547A107ACCA; Wed, 14 Apr 2021 15:11:10 +0000 (UTC) Received: from x1.localdomain (ovpn-112-168.ams2.redhat.com [10.36.112.168]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2514C5D6BA; Wed, 14 Apr 2021 15:11:07 +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, 14 Apr 2021 17:10:44 +0200 Message-Id: <20210414151049.95828-5-hdegoede@redhat.com> In-Reply-To: <20210414151049.95828-1-hdegoede@redhat.com> References: <20210414151049.95828-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Subject: [Intel-gfx] [PATCH resend 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 | 5 ++ include/drm/drm_privacy_screen_driver.h | 4 ++ 3 files changed, 76 insertions(+) diff --git a/drivers/gpu/drm/drm_privacy_screen.c b/drivers/gpu/drm/drm_privacy_screen.c index 6296fd46156c..7e78b4068e8f 100644 --- a/drivers/gpu/drm/drm_privacy_screen.c +++ b/drivers/gpu/drm/drm_privacy_screen.c @@ -254,6 +254,49 @@ 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_privacy_screen_class; priv->dev.parent = parent; @@ -399,6 +443,29 @@ void drm_privacy_screen_unregister(struct drm_privacy_screen *priv) } 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); + static int __init drm_privacy_screen_init(void) { int ret; diff --git a/include/drm/drm_privacy_screen_consumer.h b/include/drm/drm_privacy_screen_consumer.h index 169ba72bd60d..1f33dc1457ff 100644 --- a/include/drm/drm_privacy_screen_consumer.h +++ b/include/drm/drm_privacy_screen_consumer.h @@ -24,4 +24,9 @@ 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); + #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