Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 471 insertions, 0 deletions

diff --git a/drivers/gpu/drm/drm_privacy_screen.c b/drivers/gpu/drm/drm_privacy_screen.c
new file mode 100644
index 000000000..6cc39e307
--- /dev/null
+++ b/drivers/gpu/drm/drm_privacy_screen.c
@@ -0,0 +1,471 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright (C) 2020 - 2021 Red Hat, Inc.
+ *
+ * Authors:
+ * Hans de Goede <hdegoede@redhat.com>
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <drm/drm_privacy_screen_machine.h>
+#include <drm/drm_privacy_screen_consumer.h>
+#include <drm/drm_privacy_screen_driver.h>
+#include "drm_internal.h"
+
+/**
+ * DOC: overview
+ *
+ * This class allows non KMS drivers, from e.g. drivers/platform/x86 to
+ * register a privacy-screen device, which the KMS drivers can then use
+ * to implement the standard privacy-screen properties, see
+ * :ref:`Standard Connector Properties<standard_connector_properties>`.
+ *
+ * KMS drivers using a privacy-screen class device are advised to use the
+ * drm_connector_attach_privacy_screen_provider() and
+ * drm_connector_update_privacy_screen() helpers for dealing with this.
+ */
+
+#define to_drm_privacy_screen(dev) \
+	container_of(dev, struct drm_privacy_screen, dev)
+
+static DEFINE_MUTEX(drm_privacy_screen_lookup_lock);
+static LIST_HEAD(drm_privacy_screen_lookup_list);
+
+static DEFINE_MUTEX(drm_privacy_screen_devs_lock);
+static LIST_HEAD(drm_privacy_screen_devs);
+
+/*** drm_privacy_screen_machine.h functions ***/
+
+/**
+ * drm_privacy_screen_lookup_add - add an entry to the static privacy-screen
+ *    lookup list
+ * @lookup: lookup list entry to add
+ *
+ * Add an entry to the static privacy-screen lookup list. Note the
+ * &struct list_head which is part of the &struct drm_privacy_screen_lookup
+ * gets added to a list owned by the privacy-screen core. So the passed in
+ * &struct drm_privacy_screen_lookup must not be free-ed until it is removed
+ * from the lookup list by calling drm_privacy_screen_lookup_remove().
+ */
+void drm_privacy_screen_lookup_add(struct drm_privacy_screen_lookup *lookup)
+{
+	mutex_lock(&drm_privacy_screen_lookup_lock);
+	list_add(&lookup->list, &drm_privacy_screen_lookup_list);
+	mutex_unlock(&drm_privacy_screen_lookup_lock);
+}
+EXPORT_SYMBOL(drm_privacy_screen_lookup_add);
+
+/**
+ * drm_privacy_screen_lookup_remove - remove an entry to the static
+ *    privacy-screen lookup list
+ * @lookup: lookup list entry to remove
+ *
+ * Remove an entry previously added with drm_privacy_screen_lookup_add()
+ * from the static privacy-screen lookup list.
+ */
+void drm_privacy_screen_lookup_remove(struct drm_privacy_screen_lookup *lookup)
+{
+	mutex_lock(&drm_privacy_screen_lookup_lock);
+	list_del(&lookup->list);
+	mutex_unlock(&drm_privacy_screen_lookup_lock);
+}
+EXPORT_SYMBOL(drm_privacy_screen_lookup_remove);
+
+/*** drm_privacy_screen_consumer.h functions ***/
+
+static struct drm_privacy_screen *drm_privacy_screen_get_by_name(
+	const char *name)
+{
+	struct drm_privacy_screen *priv;
+	struct device *dev = NULL;
+
+	mutex_lock(&drm_privacy_screen_devs_lock);
+
+	list_for_each_entry(priv, &drm_privacy_screen_devs, list) {
+		if (strcmp(dev_name(&priv->dev), name) == 0) {
+			dev = get_device(&priv->dev);
+			break;
+		}
+	}
+
+	mutex_unlock(&drm_privacy_screen_devs_lock);
+
+	return dev ? to_drm_privacy_screen(dev) : NULL;
+}
+
+/**
+ * drm_privacy_screen_get - get a privacy-screen provider
+ * @dev: consumer-device for which to get a privacy-screen provider
+ * @con_id: (video)connector name for which to get a privacy-screen provider
+ *
+ * Get a privacy-screen provider for a privacy-screen attached to the
+ * display described by the @dev and @con_id parameters.
+ *
+ * Return:
+ * * A pointer to a &struct drm_privacy_screen on success.
+ * * ERR_PTR(-ENODEV) if no matching privacy-screen is found
+ * * ERR_PTR(-EPROBE_DEFER) if there is a matching privacy-screen,
+ *                          but it has not been registered yet.
+ */
+struct drm_privacy_screen *drm_privacy_screen_get(struct device *dev,
+						  const char *con_id)
+{
+	const char *dev_id = dev ? dev_name(dev) : NULL;
+	struct drm_privacy_screen_lookup *l;
+	struct drm_privacy_screen *priv;
+	const char *provider = NULL;
+	int match, best = -1;
+
+	/*
+	 * For now we only support using a static lookup table, which is
+	 * populated by the drm_privacy_screen_arch_init() call. This should
+	 * be extended with device-tree / fw_node lookup when support is added
+	 * for device-tree using hardware with a privacy-screen.
+	 *
+	 * The lookup algorithm was shamelessly taken from the clock
+	 * framework:
+	 *
+	 * We do slightly fuzzy matching here:
+	 *  An entry with a NULL ID is assumed to be a wildcard.
+	 *  If an entry has a device ID, it must match
+	 *  If an entry has a connection ID, it must match
+	 * Then we take the most specific entry - with the following order
+	 * of precedence: dev+con > dev only > con only.
+	 */
+	mutex_lock(&drm_privacy_screen_lookup_lock);
+
+	list_for_each_entry(l, &drm_privacy_screen_lookup_list, list) {
+		match = 0;
+
+		if (l->dev_id) {
+			if (!dev_id || strcmp(l->dev_id, dev_id))
+				continue;
+
+			match += 2;
+		}
+
+		if (l->con_id) {
+			if (!con_id || strcmp(l->con_id, con_id))
+				continue;
+
+			match += 1;
+		}
+
+		if (match > best) {
+			provider = l->provider;
+			best = match;
+		}
+	}
+
+	mutex_unlock(&drm_privacy_screen_lookup_lock);
+
+	if (!provider)
+		return ERR_PTR(-ENODEV);
+
+	priv = drm_privacy_screen_get_by_name(provider);
+	if (!priv)
+		return ERR_PTR(-EPROBE_DEFER);
+
+	return priv;
+}
+EXPORT_SYMBOL(drm_privacy_screen_get);
+
+/**
+ * drm_privacy_screen_put - release a privacy-screen reference
+ * @priv: privacy screen reference to release
+ *
+ * Release a privacy-screen provider reference gotten through
+ * drm_privacy_screen_get(). May be called with a NULL or ERR_PTR,
+ * in which case it is a no-op.
+ */
+void drm_privacy_screen_put(struct drm_privacy_screen *priv)
+{
+	if (IS_ERR_OR_NULL(priv))
+		return;
+
+	put_device(&priv->dev);
+}
+EXPORT_SYMBOL(drm_privacy_screen_put);
+
+/**
+ * drm_privacy_screen_set_sw_state - set a privacy-screen's sw-state
+ * @priv: privacy screen to set the sw-state for
+ * @sw_state: new sw-state value to set
+ *
+ * Set the sw-state of a privacy screen. If the privacy-screen is not
+ * in a locked hw-state, then the actual and hw-state of the privacy-screen
+ * will be immediately updated to the new value. If the privacy-screen is
+ * in a locked hw-state, then the new sw-state will be remembered as the
+ * requested state to put the privacy-screen in when it becomes unlocked.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int drm_privacy_screen_set_sw_state(struct drm_privacy_screen *priv,
+				    enum drm_privacy_screen_status sw_state)
+{
+	int ret = 0;
+
+	mutex_lock(&priv->lock);
+
+	if (!priv->ops) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	/*
+	 * As per the DRM connector properties documentation, setting the
+	 * sw_state while the hw_state is locked is allowed. In this case
+	 * it is a no-op other then storing the new sw_state so that it
+	 * can be honored when the state gets unlocked.
+	 * Also skip the set if the hw already is in the desired state.
+	 */
+	if (priv->hw_state >= PRIVACY_SCREEN_DISABLED_LOCKED ||
+	    priv->hw_state == sw_state) {
+		priv->sw_state = sw_state;
+		goto out;
+	}
+
+	ret = priv->ops->set_sw_state(priv, sw_state);
+out:
+	mutex_unlock(&priv->lock);
+	return ret;
+}
+EXPORT_SYMBOL(drm_privacy_screen_set_sw_state);
+
+/**
+ * drm_privacy_screen_get_state - get privacy-screen's current state
+ * @priv: privacy screen to get the state for
+ * @sw_state_ret: address where to store the privacy-screens current sw-state
+ * @hw_state_ret: address where to store the privacy-screens current hw-state
+ *
+ * Get the current state of a privacy-screen, both the sw-state and the
+ * hw-state.
+ */
+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)
+{
+	mutex_lock(&priv->lock);
+	*sw_state_ret = priv->sw_state;
+	*hw_state_ret = priv->hw_state;
+	mutex_unlock(&priv->lock);
+}
+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,
+			     struct device_attribute *attr, char *buf)
+{
+	struct drm_privacy_screen *priv = to_drm_privacy_screen(dev);
+	const char * const sw_state_names[] = {
+		"Disabled",
+		"Enabled",
+	};
+	ssize_t ret;
+
+	mutex_lock(&priv->lock);
+
+	if (!priv->ops)
+		ret = -ENODEV;
+	else if (WARN_ON(priv->sw_state >= ARRAY_SIZE(sw_state_names)))
+		ret = -ENXIO;
+	else
+		ret = sprintf(buf, "%s\n", sw_state_names[priv->sw_state]);
+
+	mutex_unlock(&priv->lock);
+	return ret;
+}
+/*
+ * RO: Do not allow setting the sw_state through sysfs, this MUST be done
+ * through the drm_properties on the drm_connector.
+ */
+static DEVICE_ATTR_RO(sw_state);
+
+static ssize_t hw_state_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct drm_privacy_screen *priv = to_drm_privacy_screen(dev);
+	const char * const hw_state_names[] = {
+		"Disabled",
+		"Enabled",
+		"Disabled, locked",
+		"Enabled, locked",
+	};
+	ssize_t ret;
+
+	mutex_lock(&priv->lock);
+
+	if (!priv->ops)
+		ret = -ENODEV;
+	else if (WARN_ON(priv->hw_state >= ARRAY_SIZE(hw_state_names)))
+		ret = -ENXIO;
+	else
+		ret = sprintf(buf, "%s\n", hw_state_names[priv->hw_state]);
+
+	mutex_unlock(&priv->lock);
+	return ret;
+}
+static DEVICE_ATTR_RO(hw_state);
+
+static struct attribute *drm_privacy_screen_attrs[] = {
+	&dev_attr_sw_state.attr,
+	&dev_attr_hw_state.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(drm_privacy_screen);
+
+static struct device_type drm_privacy_screen_type = {
+	.name = "privacy_screen",
+	.groups = drm_privacy_screen_groups,
+};
+
+static void drm_privacy_screen_device_release(struct device *dev)
+{
+	struct drm_privacy_screen *priv = to_drm_privacy_screen(dev);
+
+	kfree(priv);
+}
+
+/**
+ * drm_privacy_screen_register - register a privacy-screen
+ * @parent: parent-device for the privacy-screen
+ * @ops: &struct drm_privacy_screen_ops pointer with ops for the privacy-screen
+ * @data: Private data owned by the privacy screen provider
+ *
+ * Create and register a privacy-screen.
+ *
+ * Return:
+ * * A pointer to the created privacy-screen on success.
+ * * An ERR_PTR(errno) on failure.
+ */
+struct drm_privacy_screen *drm_privacy_screen_register(
+	struct device *parent, const struct drm_privacy_screen_ops *ops,
+	void *data)
+{
+	struct drm_privacy_screen *priv;
+	int ret;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		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;
+	priv->dev.parent = parent;
+	priv->dev.release = drm_privacy_screen_device_release;
+	dev_set_name(&priv->dev, "privacy_screen-%s", dev_name(parent));
+	priv->drvdata = data;
+	priv->ops = ops;
+
+	priv->ops->get_hw_state(priv);
+
+	ret = device_register(&priv->dev);
+	if (ret) {
+		put_device(&priv->dev);
+		return ERR_PTR(ret);
+	}
+
+	mutex_lock(&drm_privacy_screen_devs_lock);
+	list_add(&priv->list, &drm_privacy_screen_devs);
+	mutex_unlock(&drm_privacy_screen_devs_lock);
+
+	return priv;
+}
+EXPORT_SYMBOL(drm_privacy_screen_register);
+
+/**
+ * drm_privacy_screen_unregister - unregister privacy-screen
+ * @priv: privacy-screen to unregister
+ *
+ * Unregister a privacy-screen registered with drm_privacy_screen_register().
+ * May be called with a NULL or ERR_PTR, in which case it is a no-op.
+ */
+void drm_privacy_screen_unregister(struct drm_privacy_screen *priv)
+{
+	if (IS_ERR_OR_NULL(priv))
+		return;
+
+	mutex_lock(&drm_privacy_screen_devs_lock);
+	list_del(&priv->list);
+	mutex_unlock(&drm_privacy_screen_devs_lock);
+
+	mutex_lock(&priv->lock);
+	priv->drvdata = NULL;
+	priv->ops = NULL;
+	mutex_unlock(&priv->lock);
+
+	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)
+{
+	blocking_notifier_call_chain(&priv->notifier_head, 0, priv);
+}
+EXPORT_SYMBOL(drm_privacy_screen_call_notifier_chain);