On some new laptops the LCD panel has a builtin electronic privacy-screen.
We want to export this functionality as a property on the drm connector
object. But often this functionality is not exposed on the GPU but on some
other (ACPI) device.
This commit adds a privacy-screen class allowing the driver for these
other devices to register themselves as a privacy-screen provider; and
allowing the drm/kms code to get a privacy-screen provider associated
with a specific GPU/connector combo.
Changes in v2:
- Make CONFIG_DRM_PRIVACY_SCREEN a bool which controls if the drm_privacy
code gets built as part of the main drm module rather then making it
a tristate which builds its own module.
- Add a #if IS_ENABLED(CONFIG_DRM_PRIVACY_SCREEN) check to
drm_privacy_screen_consumer.h and define stubs when the check fails.
Together these 2 changes fix several dependency issues.
- Remove module related code now that this is part of the main drm.ko
- Use drm_class as class for the privacy-screen devices instead of
adding a separate class for this
Changes in v3:
- Make the static inline drm_privacy_screen_get_state() stub set sw_state
and hw_state to PRIVACY_SCREEN_DISABLED to squelch an uninitialized
variable warning when CONFIG_DRM_PRIVICAY_SCREEN is not set
Reviewed-by: Emil Velikov <emil.l.velikov@xxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
Documentation/gpu/drm-kms-helpers.rst | 15 +
MAINTAINERS | 8 +
drivers/gpu/drm/Kconfig | 4 +
drivers/gpu/drm/Makefile | 1 +
drivers/gpu/drm/drm_drv.c | 4 +
drivers/gpu/drm/drm_privacy_screen.c | 401 ++++++++++++++++++++++
include/drm/drm_privacy_screen_consumer.h | 50 +++
include/drm/drm_privacy_screen_driver.h | 80 +++++
include/drm/drm_privacy_screen_machine.h | 41 +++
9 files changed, 604 insertions(+)
create mode 100644 drivers/gpu/drm/drm_privacy_screen.c
create mode 100644 include/drm/drm_privacy_screen_consumer.h
create mode 100644 include/drm/drm_privacy_screen_driver.h
create mode 100644 include/drm/drm_privacy_screen_machine.h
diff --git a/Documentation/gpu/drm-kms-helpers.rst b/Documentation/gpu/drm-kms-helpers.rst
index 389892f36185..5d8715d2f998 100644
--- a/Documentation/gpu/drm-kms-helpers.rst
+++ b/Documentation/gpu/drm-kms-helpers.rst
@@ -423,3 +423,18 @@ Legacy CRTC/Modeset Helper Functions Reference
.. kernel-doc:: drivers/gpu/drm/drm_crtc_helper.c
:export:
+
+Privacy-screen class
+====================
+
+.. kernel-doc:: drivers/gpu/drm/drm_privacy_screen.c
+ :doc: overview
+
+.. kernel-doc:: include/drm/drm_privacy_screen_driver.h
+ :internal:
+
+.. kernel-doc:: include/drm/drm_privacy_screen_machine.h
+ :internal:
+
+.. kernel-doc:: drivers/gpu/drm/drm_privacy_screen.c
+ :export:
diff --git a/MAINTAINERS b/MAINTAINERS
index ede4a37a53b3..a272ca600f98 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6376,6 +6376,14 @@ F: drivers/gpu/drm/drm_panel.c
F: drivers/gpu/drm/panel/
F: include/drm/drm_panel.h
+DRM PRIVACY-SCREEN CLASS
+M: Hans de Goede <hdegoede@xxxxxxxxxx>
+L: dri-devel@xxxxxxxxxxxxxxxxxxxxx
+S: Maintained
+T: git git://anongit.freedesktop.org/drm/drm-misc
+F: drivers/gpu/drm/drm_privacy_screen*
+F: include/drm/drm_privacy_screen*
+
DRM TTM SUBSYSTEM
M: Christian Koenig <christian.koenig@xxxxxxx>
M: Huang Rui <ray.huang@xxxxxxx>
diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index b17e231ca6f7..7249b010ab90 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -481,3 +481,7 @@ config DRM_PANEL_ORIENTATION_QUIRKS
config DRM_LIB_RANDOM
bool
default n
+
+config DRM_PRIVACY_SCREEN
+ bool
+ default n
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 0dff40bb863c..788fc37096f6 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -32,6 +32,7 @@ drm-$(CONFIG_OF) += drm_of.o
drm-$(CONFIG_PCI) += drm_pci.o
drm-$(CONFIG_DEBUG_FS) += drm_debugfs.o drm_debugfs_crc.o
drm-$(CONFIG_DRM_LOAD_EDID_FIRMWARE) += drm_edid_load.o
+drm-$(CONFIG_DRM_PRIVACY_SCREEN) += drm_privacy_screen.o
obj-$(CONFIG_DRM_DP_AUX_BUS) += drm_dp_aux_bus.o
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 7a5097467ba5..dc293b771c3f 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -43,6 +43,7 @@
#include <drm/drm_managed.h>
#include <drm/drm_mode_object.h>
#include <drm/drm_print.h>
+#include <drm/drm_privacy_screen_machine.h>
#include "drm_crtc_internal.h"
#include "drm_internal.h"
@@ -1029,6 +1030,7 @@ static const struct file_operations drm_stub_fops = {
static void drm_core_exit(void)
{
+ drm_privacy_screen_lookup_exit();
unregister_chrdev(DRM_MAJOR, "drm");
debugfs_remove(drm_debugfs_root);
drm_sysfs_destroy();
@@ -1056,6 +1058,8 @@ static int __init drm_core_init(void)
if (ret < 0)
goto error;
+ drm_privacy_screen_lookup_init();
+
drm_core_init_complete = true;
DRM_DEBUG("Initialized\n");
diff --git a/drivers/gpu/drm/drm_privacy_screen.c b/drivers/gpu/drm/drm_privacy_screen.c
new file mode 100644
index 000000000000..294a09194bfb
--- /dev/null
+++ b/drivers/gpu/drm/drm_privacy_screen.c
@@ -0,0 +1,401 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright (C) 2020 - 2021 Red Hat, Inc.
+ *
+ * Authors:
+ * Hans de Goede <hdegoede@xxxxxxxxxx>
+ */
+
+#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.
+ */
+ if (priv->hw_state >= PRIVACY_SCREEN_DISABLED_LOCKED) {
+ 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_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
+ *
+ * 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)
+{
+ struct drm_privacy_screen *priv;
+ int ret;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return ERR_PTR(-ENOMEM);
+
+ mutex_init(&priv->lock);
+
+ 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->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->ops = NULL;
+ mutex_unlock(&priv->lock);
+
+ device_unregister(&priv->dev);
+}
+EXPORT_SYMBOL(drm_privacy_screen_unregister);
diff --git a/include/drm/drm_privacy_screen_consumer.h b/include/drm/drm_privacy_screen_consumer.h
new file mode 100644
index 000000000000..0cbd23b0453d
--- /dev/null
+++ b/include/drm/drm_privacy_screen_consumer.h
@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright (C) 2020 Red Hat, Inc.
+ *
+ * Authors:
+ * Hans de Goede <hdegoede@xxxxxxxxxx>
+ */
+
+#ifndef __DRM_PRIVACY_SCREEN_CONSUMER_H__
+#define __DRM_PRIVACY_SCREEN_CONSUMER_H__
+
+#include <linux/device.h>
+#include <drm/drm_connector.h>
+
+struct drm_privacy_screen;
+
+#if IS_ENABLED(CONFIG_DRM_PRIVACY_SCREEN)
+struct drm_privacy_screen *drm_privacy_screen_get(struct device *dev,
+ const char *con_id);
+void drm_privacy_screen_put(struct drm_privacy_screen *priv);
+
+int drm_privacy_screen_set_sw_state(struct drm_privacy_screen *priv,
+ enum drm_privacy_screen_status sw_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);
+#else
+static inline struct drm_privacy_screen *drm_privacy_screen_get(struct device *dev,
+ const char *con_id)
+{
+ return ERR_PTR(-ENODEV);
+}
+static inline void drm_privacy_screen_put(struct drm_privacy_screen *priv)
+{
+}
+static inline int drm_privacy_screen_set_sw_state(struct drm_privacy_screen *priv,
+ enum drm_privacy_screen_status sw_state)
+{
+ return -ENODEV;
+}
+static inline 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)
+{
+ *sw_state_ret = PRIVACY_SCREEN_DISABLED;
+ *hw_state_ret = PRIVACY_SCREEN_DISABLED;
+}
+#endif
+
+#endif
diff --git a/include/drm/drm_privacy_screen_driver.h b/include/drm/drm_privacy_screen_driver.h
new file mode 100644
index 000000000000..5187ae52eb03
--- /dev/null
+++ b/include/drm/drm_privacy_screen_driver.h
@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright (C) 2020 Red Hat, Inc.
+ *
+ * Authors:
+ * Hans de Goede <hdegoede@xxxxxxxxxx>
+ */
+
+#ifndef __DRM_PRIVACY_SCREEN_DRIVER_H__
+#define __DRM_PRIVACY_SCREEN_DRIVER_H__
+
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <drm/drm_connector.h>
+
+struct drm_privacy_screen;
+
+/**
+ * struct drm_privacy_screen_ops - drm_privacy_screen operations
+ *
+ * Defines the operations which the privacy-screen class code may call.
+ * These functions should be implemented by the privacy-screen driver.
+ */
+struct drm_privacy_screen_ops {
+ /**
+ * @set_sw_state: Called to request a change of the privacy-screen
+ * state. The privacy-screen class code contains a check to avoid this
+ * getting called when the hw_state reports the state is locked.
+ * It is the driver's responsibility to update sw_state and hw_state.
+ * This is always called with the drm_privacy_screen's lock held.
+ */
+ int (*set_sw_state)(struct drm_privacy_screen *priv,
+ enum drm_privacy_screen_status sw_state);
+ /**
+ * @get_hw_state: Called to request that the driver gets the current
+ * privacy-screen state from the hardware and then updates sw_state and
+ * hw_state accordingly. This will be called by the core just before
+ * the privacy-screen is registered in sysfs.
+ */
+ void (*get_hw_state)(struct drm_privacy_screen *priv);
+};
+
+/**
+ * struct drm_privacy_screen - central privacy-screen structure
+ *
+ * Central privacy-screen structure, this contains the struct device used
+ * to register the screen in sysfs, the screen's state, ops, etc.
+ */
+struct drm_privacy_screen {
+ /** @dev: device used to register the privacy-screen in sysfs. */
+ struct device dev;
+ /** @lock: mutex protection all fields in this struct. */
+ struct mutex lock;
+ /** @list: privacy-screen devices list list-entry. */
+ struct list_head list;
+ /**
+ * @ops: &struct drm_privacy_screen_ops for this privacy-screen.
+ * This is NULL if the driver has unregistered the privacy-screen.
+ */
+ const struct drm_privacy_screen_ops *ops;
+ /**
+ * @sw_state: The privacy-screen's software state, see
+ * :ref:`Standard Connector Properties<standard_connector_properties>`
+ * for more info.
+ */
+ enum drm_privacy_screen_status sw_state;
+ /**
+ * @hw_state: The privacy-screen's hardware state, see
+ * :ref:`Standard Connector Properties<standard_connector_properties>`
+ * for more info.
+ */
+ enum drm_privacy_screen_status hw_state;
+};
+
+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);
+
+#endif
diff --git a/include/drm/drm_privacy_screen_machine.h b/include/drm/drm_privacy_screen_machine.h
new file mode 100644
index 000000000000..aaa0d38cce92
--- /dev/null
+++ b/include/drm/drm_privacy_screen_machine.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright (C) 2020 Red Hat, Inc.
+ *
+ * Authors:
+ * Hans de Goede <hdegoede@xxxxxxxxxx>
+ */
+
+#ifndef __DRM_PRIVACY_SCREEN_MACHINE_H__
+#define __DRM_PRIVACY_SCREEN_MACHINE_H__
+
+#include <linux/list.h>
+
+/**
+ * struct drm_privacy_screen_lookup - static privacy-screen lookup list entry
+ *
+ * Used for the static lookup-list for mapping privacy-screen consumer
+ * dev-connector pairs to a privacy-screen provider.
+ */
+struct drm_privacy_screen_lookup {
+ /** @list: Lookup list list-entry. */
+ struct list_head list;
+ /** @dev_id: Consumer device name or NULL to match all devices. */
+ const char *dev_id;
+ /** @con_id: Consumer connector name or NULL to match all connectors. */
+ const char *con_id;
+ /** @provider: dev_name() of the privacy_screen provider. */
+ const char *provider;
+};
+
+void drm_privacy_screen_lookup_add(struct drm_privacy_screen_lookup *lookup);
+void drm_privacy_screen_lookup_remove(struct drm_privacy_screen_lookup *lookup);
+
+static inline void drm_privacy_screen_lookup_init(void)
+{
+}
+static inline void drm_privacy_screen_lookup_exit(void)
+{
+}
+
+#endif
--
2.31.1
