[PATCH 0/8] drm + usb-type-c: Add support for out-of-band hotplug notification (v3)

[PATCH 0/8] drm + usb-type-c: Add support for out-of-band hotplug notification (v3)

[Hans de Goede]

Hi All,

Here is v3 of my patchset making DP over Type-C work on devices where the
Type-C controller does not drive the HPD pin on the GPU, but instead
we need to forward HPD events from the Type-C controller to the DRM driver.

Changes in v3:
- Base on top of latest drm-tip, which should fix the CI being unable to
  apply (and thus to test) the patches
- Make intel_acpi_assign_connector_fwnodes() take a ref on the fwnode
  it stores in connector->fwnode and have drm_connector_cleanup() put
  this reference
- Drop data argument from drm_connector_oob_hotplug_event()
- Make the Type-C DP altmode code only call drm_connector_oob_hotplug_event()
  when the HPD bit in the status vdo changes
- Drop the platform/x86/intel_cht_int33fe: Correct "displayport" fwnode
  reference patch, this will be merged independently through the pdx86 tree

Changes in v2:
- Replace the bogus "drm/connector: Make the drm_sysfs connector->kdev
  device hold a reference to the connector" patch with:
  "drm/connector: Give connector sysfs devices there own device_type"
  the new patch is a dep for patch 2/9 see the patches

- Stop using a class-dev-iter, instead at a global connector list
  to drm_connector.c and use that to find the connector by the fwnode,
  similar to how we already do this in drm_panel.c and drm_bridge.c

- Make drm_connector_oob_hotplug_event() take a fwnode pointer as
  argument, rather then a drm_connector pointer and let it do the
  lookup itself. This allows making drm_connector_find_by_fwnode() a
  drm-internal function and avoids code outside the drm subsystem
  potentially holding on the a drm_connector reference for a longer
  period.

This series not only touches drm subsys files but it also touches
drivers/usb/typec/altmodes/typec_displayport.c, that file usually
does not see a whole lot of changes. So I believe it would be best
to just merge the entire series through drm-misc, Assuming we can
get an ack from Greg for merging the typec_displayport.c changes
this way.

Regards,

Hans


Hans de Goede (7):
  drm/connector: Give connector sysfs devices there own device_type
  drm/connector: Add a fwnode pointer to drm_connector and register with
    ACPI (v2)
  drm/connector: Add drm_connector_find_by_fwnode() function (v2)
  drm/connector: Add support for out-of-band hotplug notification (v3)
  drm/i915/dp: Add support for out-of-bound hotplug events
  usb: typec: altmodes/displayport: Make dp_altmode_notify() more
    generic
  usb: typec: altmodes/displayport: Notify drm subsys of hotplug events

Heikki Krogerus (1):
  drm/i915: Associate ACPI connector nodes with connector entries (v2)

 drivers/gpu/drm/drm_connector.c              | 79 ++++++++++++++++++
 drivers/gpu/drm/drm_crtc_internal.h          |  1 +
 drivers/gpu/drm/drm_sysfs.c                  | 87 +++++++++++++++++---
 drivers/gpu/drm/i915/display/intel_acpi.c    | 46 +++++++++++
 drivers/gpu/drm/i915/display/intel_acpi.h    |  3 +
 drivers/gpu/drm/i915/display/intel_display.c |  1 +
 drivers/gpu/drm/i915/display/intel_dp.c      | 12 +++
 drivers/usb/typec/altmodes/Kconfig           |  1 +
 drivers/usb/typec/altmodes/displayport.c     | 58 ++++++++-----
 include/drm/drm_connector.h                  | 25 ++++++
 10 files changed, 278 insertions(+), 35 deletions(-)

-- 
2.31.1

[PATCH 1/8] drm/connector: Give connector sysfs devices there own device_type

[Hans de Goede]

Give connector sysfs devices there own device_type, this allows us to
check if a device passed to functions dealing with generic devices is
a drm_connector or not.

A check like this is necessary in the drm_connector_acpi_bus_match()
function added in the next patch in this series.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/gpu/drm/drm_sysfs.c | 50 +++++++++++++++++++++++++++----------
 1 file changed, 37 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c
index 968a9560b4aa..f9d92bbb1f98 100644
--- a/drivers/gpu/drm/drm_sysfs.c
+++ b/drivers/gpu/drm/drm_sysfs.c
@@ -50,6 +50,10 @@ static struct device_type drm_sysfs_device_minor = {
 	.name = "drm_minor"
 };
 
+static struct device_type drm_sysfs_device_connector = {
+	.name = "drm_connector",
+};
+
 struct class *drm_class;
 
 static char *drm_devnode(struct device *dev, umode_t *mode)
@@ -102,6 +106,11 @@ void drm_sysfs_destroy(void)
 	drm_class = NULL;
 }
 
+static void drm_sysfs_release(struct device *dev)
+{
+	kfree(dev);
+}
+
 /*
  * Connector properties
  */
@@ -273,27 +282,47 @@ static const struct attribute_group *connector_dev_groups[] = {
 int drm_sysfs_connector_add(struct drm_connector *connector)
 {
 	struct drm_device *dev = connector->dev;
+	struct device *kdev;
+	int r;
 
 	if (connector->kdev)
 		return 0;
 
-	connector->kdev =
-		device_create_with_groups(drm_class, dev->primary->kdev, 0,
-					  connector, connector_dev_groups,
-					  "card%d-%s", dev->primary->index,
-					  connector->name);
+	kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
+	if (!kdev)
+		return -ENOMEM;
+
+	device_initialize(kdev);
+	kdev->class = drm_class;
+	kdev->type = &drm_sysfs_device_connector;
+	kdev->parent = dev->primary->kdev;
+	kdev->groups = connector_dev_groups;
+	kdev->release = drm_sysfs_release;
+	dev_set_drvdata(kdev, connector);
+
+	r = dev_set_name(kdev, "card%d-%s", dev->primary->index, connector->name);
+	if (r)
+		goto err_free;
+
 	DRM_DEBUG("adding \"%s\" to sysfs\n",
 		  connector->name);
 
-	if (IS_ERR(connector->kdev)) {
-		DRM_ERROR("failed to register connector device: %ld\n", PTR_ERR(connector->kdev));
-		return PTR_ERR(connector->kdev);
+	r = device_add(kdev);
+	if (r) {
+		DRM_ERROR("failed to register connector device: %d\n", r);
+		goto err_free;
 	}
 
+	connector->kdev = kdev;
+
 	if (connector->ddc)
 		return sysfs_create_link(&connector->kdev->kobj,
 				 &connector->ddc->dev.kobj, "ddc");
 	return 0;
+
+err_free:
+	put_device(kdev);
+	return r;
 }
 
 void drm_sysfs_connector_remove(struct drm_connector *connector)
@@ -374,11 +403,6 @@ void drm_sysfs_connector_status_event(struct drm_connector *connector,
 }
 EXPORT_SYMBOL(drm_sysfs_connector_status_event);
 
-static void drm_sysfs_release(struct device *dev)
-{
-	kfree(dev);
-}
-
 struct device *drm_sysfs_minor_alloc(struct drm_minor *minor)
 {
 	const char *minor_str;
-- 
2.31.1

[PATCH 2/8] drm/connector: Add a fwnode pointer to drm_connector and register with ACPI (v2)

[Hans de Goede]

Add a fwnode pointer to struct drm_connector and register an acpi_bus_type
for the connectors with the ACPI subsystem (when CONFIG_ACPI is enabled).

The adding of the fwnode pointer allows drivers to associate a fwnode
that represents a connector with that connector.

When the new fwnode pointer points to an ACPI-companion, then the new
acpi_bus_type will cause the ACPI subsys to bind the device instantiated
for the connector with the fwnode by calling acpi_bind_one(). This will
result in a firmware_node symlink under /sys/class/card#-<connecter-name>/
which helps to verify that the fwnode-s and connectors are properly
matched.

Changes in v2:
- Make drm_connector_cleanup() call fwnode_handle_put() on
  connector->fwnode and document this

Co-developed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/gpu/drm/drm_connector.c |  2 ++
 drivers/gpu/drm/drm_sysfs.c     | 37 +++++++++++++++++++++++++++++++++
 include/drm/drm_connector.h     |  8 +++++++
 3 files changed, 47 insertions(+)

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 9de145351546..6b5b4762c434 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -474,6 +474,8 @@ void drm_connector_cleanup(struct drm_connector *connector)
 	drm_mode_object_unregister(dev, &connector->base);
 	kfree(connector->name);
 	connector->name = NULL;
+	fwnode_handle_put(connector->fwnode);
+	connector->fwnode = NULL;
 	spin_lock_irq(&dev->mode_config.connector_list_lock);
 	list_del(&connector->head);
 	dev->mode_config.num_connector--;
diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c
index f9d92bbb1f98..bf9edce8e2d1 100644
--- a/drivers/gpu/drm/drm_sysfs.c
+++ b/drivers/gpu/drm/drm_sysfs.c
@@ -10,6 +10,7 @@
  * Copyright (c) 2003-2004 IBM Corp.
  */
 
+#include <linux/acpi.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/export.h>
@@ -56,6 +57,39 @@ static struct device_type drm_sysfs_device_connector = {
 
 struct class *drm_class;
 
+#ifdef CONFIG_ACPI
+static bool drm_connector_acpi_bus_match(struct device *dev)
+{
+	return dev->type == &drm_sysfs_device_connector;
+}
+
+static struct acpi_device *drm_connector_acpi_find_companion(struct device *dev)
+{
+	struct drm_connector *connector = to_drm_connector(dev);
+
+	return to_acpi_device_node(connector->fwnode);
+}
+
+static struct acpi_bus_type drm_connector_acpi_bus = {
+	.name = "drm_connector",
+	.match = drm_connector_acpi_bus_match,
+	.find_companion = drm_connector_acpi_find_companion,
+};
+
+static void drm_sysfs_acpi_register(void)
+{
+	register_acpi_bus_type(&drm_connector_acpi_bus);
+}
+
+static void drm_sysfs_acpi_unregister(void)
+{
+	unregister_acpi_bus_type(&drm_connector_acpi_bus);
+}
+#else
+static void drm_sysfs_acpi_register(void) { }
+static void drm_sysfs_acpi_unregister(void) { }
+#endif
+
 static char *drm_devnode(struct device *dev, umode_t *mode)
 {
 	return kasprintf(GFP_KERNEL, "dri/%s", dev_name(dev));
@@ -89,6 +123,8 @@ int drm_sysfs_init(void)
 	}
 
 	drm_class->devnode = drm_devnode;
+
+	drm_sysfs_acpi_register();
 	return 0;
 }
 
@@ -101,6 +137,7 @@ void drm_sysfs_destroy(void)
 {
 	if (IS_ERR_OR_NULL(drm_class))
 		return;
+	drm_sysfs_acpi_unregister();
 	class_remove_file(drm_class, &class_attr_version.attr);
 	class_destroy(drm_class);
 	drm_class = NULL;
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 1922b278ffad..2c4cbc686a22 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -1223,6 +1223,14 @@ struct drm_connector {
 	struct device *kdev;
 	/** @attr: sysfs attributes */
 	struct device_attribute *attr;
+	/**
+	 * @fwnode: associated fwnode supplied by platform firmware
+	 *
+	 * Drivers can set this to associate a fwnode with a connector, drivers
+	 * are expected to get a reference on the fwnode when setting this.
+	 * drm_connector_cleanup() will call fwnode_handle_put() on this.
+	 */
+	struct fwnode_handle *fwnode;
 
 	/**
 	 * @head:
-- 
2.31.1

[PATCH 3/8] drm/connector: Add drm_connector_find_by_fwnode() function (v2)

[Hans de Goede]

Add a function to find a connector based on a fwnode.

This will be used by the new drm_connector_oob_hotplug_event()
function which is added by the next patch in this patch-set.

Changes in v2:
- Complete rewrite to use a global connector list in drm_connector.c
  rather then using a class-dev-iter in drm_sysfs.c

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/gpu/drm/drm_connector.c     | 50 +++++++++++++++++++++++++++++
 drivers/gpu/drm/drm_crtc_internal.h |  1 +
 include/drm/drm_connector.h         |  8 +++++
 3 files changed, 59 insertions(+)

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 6b5b4762c434..70aa50ea7b8b 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -65,6 +65,14 @@
  * support can instead use e.g. drm_helper_hpd_irq_event().
  */
 
+/*
+ * Global connector list for drm_connector_find_by_fwnode().
+ * Note drm_connector_[un]register() first take connector->lock and then
+ * take the connector_list_lock.
+ */
+static DEFINE_MUTEX(connector_list_lock);
+static LIST_HEAD(connector_list);
+
 struct drm_conn_prop_enum_list {
 	int type;
 	const char *name;
@@ -267,6 +275,7 @@ int drm_connector_init(struct drm_device *dev,
 		goto out_put_type_id;
 	}
 
+	INIT_LIST_HEAD(&connector->global_connector_list_entry);
 	INIT_LIST_HEAD(&connector->probed_modes);
 	INIT_LIST_HEAD(&connector->modes);
 	mutex_init(&connector->mutex);
@@ -534,6 +543,9 @@ int drm_connector_register(struct drm_connector *connector)
 	/* Let userspace know we have a new connector */
 	drm_sysfs_hotplug_event(connector->dev);
 
+	mutex_lock(&connector_list_lock);
+	list_add_tail(&connector->global_connector_list_entry, &connector_list);
+	mutex_unlock(&connector_list_lock);
 	goto unlock;
 
 err_debugfs:
@@ -562,6 +574,10 @@ void drm_connector_unregister(struct drm_connector *connector)
 		return;
 	}
 
+	mutex_lock(&connector_list_lock);
+	list_del_init(&connector->global_connector_list_entry);
+	mutex_unlock(&connector_list_lock);
+
 	if (connector->funcs->early_unregister)
 		connector->funcs->early_unregister(connector);
 
@@ -2473,6 +2489,40 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,
 	return ret;
 }
 
+/**
+ * drm_connector_find_by_fwnode - Find a connector based on the associated fwnode
+ * @fwnode: fwnode for which to find the matching drm_connector
+ *
+ * This functions looks up a drm_connector based on its associated fwnode. When
+ * a connector is found a reference to the connector is returned. The caller must
+ * call drm_connector_put() to release this reference when it is done with the
+ * connector.
+ *
+ * Returns: A reference to the found connector or an ERR_PTR().
+ */
+struct drm_connector *drm_connector_find_by_fwnode(struct fwnode_handle *fwnode)
+{
+	struct drm_connector *connector, *found = ERR_PTR(-ENODEV);
+
+	if (!fwnode)
+		return ERR_PTR(-ENODEV);
+
+	mutex_lock(&connector_list_lock);
+
+	list_for_each_entry(connector, &connector_list, global_connector_list_entry) {
+		if (connector->fwnode == fwnode ||
+		    (connector->fwnode && connector->fwnode->secondary == fwnode)) {
+			drm_connector_get(connector);
+			found = connector;
+			break;
+		}
+	}
+
+	mutex_unlock(&connector_list_lock);
+
+	return found;
+}
+
 
 /**
  * DOC: Tile group
diff --git a/drivers/gpu/drm/drm_crtc_internal.h b/drivers/gpu/drm/drm_crtc_internal.h
index 54d4cf1233e9..6e28fc00a740 100644
--- a/drivers/gpu/drm/drm_crtc_internal.h
+++ b/drivers/gpu/drm/drm_crtc_internal.h
@@ -185,6 +185,7 @@ int drm_connector_set_obj_prop(struct drm_mode_object *obj,
 int drm_connector_create_standard_properties(struct drm_device *dev);
 const char *drm_get_connector_force_name(enum drm_connector_force force);
 void drm_connector_free_work_fn(struct work_struct *work);
+struct drm_connector *drm_connector_find_by_fwnode(struct fwnode_handle *fwnode);
 
 /* IOCTL */
 int drm_connector_property_set_ioctl(struct drm_device *dev,
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 2c4cbc686a22..8ae5dbe3d4ae 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -1242,6 +1242,14 @@ struct drm_connector {
 	 */
 	struct list_head head;
 
+	/**
+	 * @global_connector_list_entry:
+	 *
+	 * Connector entry in the global connector-list, used by
+	 * drm_connector_find_by_fwnode().
+	 */
+	struct list_head global_connector_list_entry;
+
 	/** @base: base KMS object */
 	struct drm_mode_object base;
 
-- 
2.31.1

[PATCH 4/8] drm/connector: Add support for out-of-band hotplug notification (v3)

[Hans de Goede]

Add a new drm_connector_oob_hotplug_event() function and
oob_hotplug_event drm_connector_funcs member.

On some hardware a hotplug event notification may come from outside the
display driver / device. An example of this is some USB Type-C setups
where the hardware muxes the DisplayPort data and aux-lines but does
not pass the altmode HPD status bit to the GPU's DP HPD pin.

In cases like this the new drm_connector_oob_hotplug_event() function can
be used to report these out-of-band events.

Changes in v2:
- Make drm_connector_oob_hotplug_event() take a fwnode as argument and
  have it call drm_connector_find_by_fwnode() internally. This allows
  making drm_connector_find_by_fwnode() a drm-internal function and
  avoids code outside the drm subsystem potentially holding on the
  a drm_connector reference for a longer period.

Changes in v3:
- Drop the data argument to the drm_connector_oob_hotplug_event
  function since it is not used atm. This can be re-added later when
  a use for it actually arises.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/gpu/drm/drm_connector.c | 27 +++++++++++++++++++++++++++
 include/drm/drm_connector.h     |  9 +++++++++
 2 files changed, 36 insertions(+)

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 70aa50ea7b8b..462a5752e994 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -2523,6 +2523,33 @@ struct drm_connector *drm_connector_find_by_fwnode(struct fwnode_handle *fwnode)
 	return found;
 }
 
+/**
+ * drm_connector_oob_hotplug_event - Report out-of-band hotplug event to connector
+ * @connector: connector to report the event on
+ *
+ * On some hardware a hotplug event notification may come from outside the display
+ * driver / device. An example of this is some USB Type-C setups where the hardware
+ * muxes the DisplayPort data and aux-lines but does not pass the altmode HPD
+ * status bit to the GPU's DP HPD pin.
+ *
+ * This function can be used to report these out-of-band events after obtaining
+ * a drm_connector reference through calling drm_connector_find_by_fwnode().
+ */
+void drm_connector_oob_hotplug_event(struct fwnode_handle *connector_fwnode)
+{
+	struct drm_connector *connector;
+
+	connector = drm_connector_find_by_fwnode(connector_fwnode);
+	if (IS_ERR(connector))
+		return;
+
+	if (connector->funcs->oob_hotplug_event)
+		connector->funcs->oob_hotplug_event(connector);
+
+	drm_connector_put(connector);
+}
+EXPORT_SYMBOL(drm_connector_oob_hotplug_event);
+
 
 /**
  * DOC: Tile group
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 8ae5dbe3d4ae..9150b8967366 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -1079,6 +1079,14 @@ struct drm_connector_funcs {
 	 */
 	void (*atomic_print_state)(struct drm_printer *p,
 				   const struct drm_connector_state *state);
+
+	/**
+	 * @oob_hotplug_event:
+	 *
+	 * This will get called when a hotplug-event for a drm-connector
+	 * has been received from a source outside the display driver / device.
+	 */
+	void (*oob_hotplug_event)(struct drm_connector *connector);
 };
 
 /**
@@ -1661,6 +1669,7 @@ drm_connector_is_unregistered(struct drm_connector *connector)
 		DRM_CONNECTOR_UNREGISTERED;
 }
 
+void drm_connector_oob_hotplug_event(struct fwnode_handle *connector_fwnode);
 const char *drm_get_connector_type_name(unsigned int connector_type);
 const char *drm_get_connector_status_name(enum drm_connector_status status);
 const char *drm_get_subpixel_order_name(enum subpixel_order order);
-- 
2.31.1

[PATCH 5/8] drm/i915: Associate ACPI connector nodes with connector entries (v2)

[Hans de Goede]

From: Heikki Krogerus <heikki.krogerus@linux.intel.com>

On Intel platforms we know that the ACPI connector device
node order will follow the order the driver (i915) decides.
The decision is made using the custom Intel ACPI OpRegion
(intel_opregion.c), though the driver does not actually know
that the values it sends to ACPI there are used for
associating a device node for the connectors, and assigning
address for them.

In reality that custom Intel ACPI OpRegion actually violates
ACPI specification (we supply dynamic information to objects
that are defined static, for example _ADR), however, it
makes assigning correct connector node for a connector entry
straightforward (it's one-on-one mapping).

Changes in v2 (Hans de goede):
- Take a reference on the fwnode which we assign to the connector,
  for ACPI nodes this is a no-op but in the future we may see
  software-fwnodes assigned to connectors which are ref-counted.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/gpu/drm/i915/display/intel_acpi.c    | 46 ++++++++++++++++++++
 drivers/gpu/drm/i915/display/intel_acpi.h    |  3 ++
 drivers/gpu/drm/i915/display/intel_display.c |  1 +
 3 files changed, 50 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_acpi.c b/drivers/gpu/drm/i915/display/intel_acpi.c
index 833d0c1be4f1..37077b19cf58 100644
--- a/drivers/gpu/drm/i915/display/intel_acpi.c
+++ b/drivers/gpu/drm/i915/display/intel_acpi.c
@@ -263,3 +263,49 @@ void intel_acpi_device_id_update(struct drm_i915_private *dev_priv)
 	}
 	drm_connector_list_iter_end(&conn_iter);
 }
+
+/* NOTE: The connector order must be final before this is called. */
+void intel_acpi_assign_connector_fwnodes(struct drm_i915_private *i915)
+{
+	struct drm_connector_list_iter conn_iter;
+	struct drm_device *drm_dev = &i915->drm;
+	struct fwnode_handle *fwnode = NULL;
+	struct drm_connector *connector;
+	struct acpi_device *adev;
+
+	drm_connector_list_iter_begin(drm_dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter) {
+		/* Always getting the next, even when the last was not used. */
+		fwnode = device_get_next_child_node(drm_dev->dev, fwnode);
+		if (!fwnode)
+			break;
+
+		switch (connector->connector_type) {
+		case DRM_MODE_CONNECTOR_LVDS:
+		case DRM_MODE_CONNECTOR_eDP:
+		case DRM_MODE_CONNECTOR_DSI:
+			/*
+			 * Integrated displays have a specific address 0x1f on
+			 * most Intel platforms, but not on all of them.
+			 */
+			adev = acpi_find_child_device(ACPI_COMPANION(drm_dev->dev),
+						      0x1f, 0);
+			if (adev) {
+				connector->fwnode =
+					fwnode_handle_get(acpi_fwnode_handle(adev));
+				break;
+			}
+			fallthrough;
+		default:
+			connector->fwnode = fwnode_handle_get(fwnode);
+			break;
+		}
+	}
+	drm_connector_list_iter_end(&conn_iter);
+	/*
+	 * device_get_next_child_node() takes a reference on the fwnode, if
+	 * we stopped iterating because we are out of connectors we need to
+	 * put this, otherwise fwnode is NULL and the put is a no-op.
+	 */
+	fwnode_handle_put(fwnode);
+}
diff --git a/drivers/gpu/drm/i915/display/intel_acpi.h b/drivers/gpu/drm/i915/display/intel_acpi.h
index e8b068661d22..d2435691f4b5 100644
--- a/drivers/gpu/drm/i915/display/intel_acpi.h
+++ b/drivers/gpu/drm/i915/display/intel_acpi.h
@@ -12,11 +12,14 @@ struct drm_i915_private;
 void intel_register_dsm_handler(void);
 void intel_unregister_dsm_handler(void);
 void intel_acpi_device_id_update(struct drm_i915_private *i915);
+void intel_acpi_assign_connector_fwnodes(struct drm_i915_private *i915);
 #else
 static inline void intel_register_dsm_handler(void) { return; }
 static inline void intel_unregister_dsm_handler(void) { return; }
 static inline
 void intel_acpi_device_id_update(struct drm_i915_private *i915) { return; }
+static inline
+void intel_acpi_assign_connector_fwnodes(struct drm_i915_private *i915) { return; }
 #endif /* CONFIG_ACPI */
 
 #endif /* __INTEL_ACPI_H__ */
diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index f8320ab7592e..5294eb25c623 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -11912,6 +11912,7 @@ int intel_modeset_init_nogem(struct drm_i915_private *i915)
 
 	drm_modeset_lock_all(dev);
 	intel_modeset_setup_hw_state(dev, dev->mode_config.acquire_ctx);
+	intel_acpi_assign_connector_fwnodes(i915);
 	drm_modeset_unlock_all(dev);
 
 	for_each_intel_crtc(dev, crtc) {
-- 
2.31.1

[PATCH 6/8] drm/i915/dp: Add support for out-of-bound hotplug events

[Hans de Goede]

On some Cherry Trail devices, DisplayPort over Type-C is supported through
a USB-PD microcontroller (e.g. a fusb302) + a mux to switch the superspeed
datalines between USB-3 and DP (e.g. a pi3usb30532). The kernel in this
case does the PD/alt-mode negotiation itself, rather then everything being
handled in firmware.

So the kernel itself picks an alt-mode, tells the Type-C "dongle" to switch
to DP mode and sets the mux accordingly. In this setup the HPD pin is not
connected, so the i915 driver needs to respond to a software event and scan
the DP port for changes manually.

This commit adds support for this. Together with the recent addition of
DP alt-mode support to the Type-C subsystem this makes DP over Type-C
work on these devices.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index dfa7da928ae5..554090e6ab7d 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -4571,6 +4571,17 @@ static int intel_dp_connector_atomic_check(struct drm_connector *conn,
 	return intel_modeset_synced_crtcs(state, conn);
 }
 
+static void intel_dp_oob_hotplug_event(struct drm_connector *connector)
+{
+	struct intel_encoder *encoder = intel_attached_encoder(to_intel_connector(connector));
+	struct drm_i915_private *i915 = to_i915(connector->dev);
+
+	spin_lock_irq(&i915->irq_lock);
+	i915->hotplug.event_bits |= BIT(encoder->hpd_pin);
+	spin_unlock_irq(&i915->irq_lock);
+	queue_delayed_work(system_wq, &i915->hotplug.hotplug_work, 0);
+}
+
 static const struct drm_connector_funcs intel_dp_connector_funcs = {
 	.force = intel_dp_force,
 	.fill_modes = drm_helper_probe_single_connector_modes,
@@ -4581,6 +4592,7 @@ static const struct drm_connector_funcs intel_dp_connector_funcs = {
 	.destroy = intel_connector_destroy,
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 	.atomic_duplicate_state = intel_digital_connector_duplicate_state,
+	.oob_hotplug_event = intel_dp_oob_hotplug_event,
 };
 
 static const struct drm_connector_helper_funcs intel_dp_connector_helper_funcs = {
-- 
2.31.1

[PATCH 7/8] usb: typec: altmodes/displayport: Make dp_altmode_notify() more generic

[Hans de Goede]

Make dp_altmode_notify() handle the dp->data.conf == 0 case too,
rather then having separate code-paths for this in various places
which call it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/usb/typec/altmodes/displayport.c | 35 +++++++++---------------
 1 file changed, 13 insertions(+), 22 deletions(-)

diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c
index b7f094435b00..aa669b9cf70e 100644
--- a/drivers/usb/typec/altmodes/displayport.c
+++ b/drivers/usb/typec/altmodes/displayport.c
@@ -66,10 +66,17 @@ struct dp_altmode {
 
 static int dp_altmode_notify(struct dp_altmode *dp)
 {
-	u8 state = get_count_order(DP_CONF_GET_PIN_ASSIGN(dp->data.conf));
+	unsigned long conf;
+	u8 state;
+
+	if (dp->data.conf) {
+		state = get_count_order(DP_CONF_GET_PIN_ASSIGN(dp->data.conf));
+		conf = TYPEC_MODAL_STATE(state);
+	} else {
+		conf = TYPEC_STATE_USB;
+	}
 
-	return typec_altmode_notify(dp->alt, TYPEC_MODAL_STATE(state),
-				   &dp->data);
+	return typec_altmode_notify(dp->alt, conf, &dp->data);
 }
 
 static int dp_altmode_configure(struct dp_altmode *dp, u8 con)
@@ -137,21 +144,10 @@ static int dp_altmode_status_update(struct dp_altmode *dp)
 
 static int dp_altmode_configured(struct dp_altmode *dp)
 {
-	int ret;
-
 	sysfs_notify(&dp->alt->dev.kobj, "displayport", "configuration");
-
-	if (!dp->data.conf)
-		return typec_altmode_notify(dp->alt, TYPEC_STATE_USB,
-					    &dp->data);
-
-	ret = dp_altmode_notify(dp);
-	if (ret)
-		return ret;
-
 	sysfs_notify(&dp->alt->dev.kobj, "displayport", "pin_assignment");
 
-	return 0;
+	return dp_altmode_notify(dp);
 }
 
 static int dp_altmode_configure_vdm(struct dp_altmode *dp, u32 conf)
@@ -172,13 +168,8 @@ static int dp_altmode_configure_vdm(struct dp_altmode *dp, u32 conf)
 	}
 
 	ret = typec_altmode_vdm(dp->alt, header, &conf, 2);
-	if (ret) {
-		if (DP_CONF_GET_PIN_ASSIGN(dp->data.conf))
-			dp_altmode_notify(dp);
-		else
-			typec_altmode_notify(dp->alt, TYPEC_STATE_USB,
-					     &dp->data);
-	}
+	if (ret)
+		dp_altmode_notify(dp);
 
 	return ret;
 }
-- 
2.31.1

[PATCH 8/8] usb: typec: altmodes/displayport: Notify drm subsys of hotplug events

[Hans de Goede]

Use the new drm_connector_oob_hotplug_event() functions to let drm/kms
drivers know about DisplayPort over Type-C hotplug events.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v3:
- Only call drm_connector_oob_hotplug_event() on hpd status bit change
- Adjust for drm_connector_oob_hotplug_event() no longer having a data
  argument

Changes in v2:
- Add missing depends on DRM to TYPEC_DP_ALTMODE Kconfig entry
---
 drivers/usb/typec/altmodes/Kconfig       |  1 +
 drivers/usb/typec/altmodes/displayport.c | 23 +++++++++++++++++++++++
 2 files changed, 24 insertions(+)

diff --git a/drivers/usb/typec/altmodes/Kconfig b/drivers/usb/typec/altmodes/Kconfig
index 60d375e9c3c7..1a6b5e872b0d 100644
--- a/drivers/usb/typec/altmodes/Kconfig
+++ b/drivers/usb/typec/altmodes/Kconfig
@@ -4,6 +4,7 @@ menu "USB Type-C Alternate Mode drivers"
 
 config TYPEC_DP_ALTMODE
 	tristate "DisplayPort Alternate Mode driver"
+	depends on DRM
 	help
 	  DisplayPort USB Type-C Alternate Mode allows DisplayPort
 	  displays and adapters to be attached to the USB Type-C
diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c
index aa669b9cf70e..c1d8c23baa39 100644
--- a/drivers/usb/typec/altmodes/displayport.c
+++ b/drivers/usb/typec/altmodes/displayport.c
@@ -11,8 +11,10 @@
 #include <linux/delay.h>
 #include <linux/mutex.h>
 #include <linux/module.h>
+#include <linux/property.h>
 #include <linux/usb/pd_vdo.h>
 #include <linux/usb/typec_dp.h>
+#include <drm/drm_connector.h>
 #include "displayport.h"
 
 #define DP_HEADER(_dp, ver, cmd)	(VDO((_dp)->alt->svid, 1, ver, cmd)	\
@@ -57,11 +59,13 @@ struct dp_altmode {
 	struct typec_displayport_data data;
 
 	enum dp_state state;
+	bool hpd;
 
 	struct mutex lock; /* device lock */
 	struct work_struct work;
 	struct typec_altmode *alt;
 	const struct typec_altmode *port;
+	struct fwnode_handle *connector_fwnode;
 };
 
 static int dp_altmode_notify(struct dp_altmode *dp)
@@ -125,6 +129,7 @@ static int dp_altmode_configure(struct dp_altmode *dp, u8 con)
 static int dp_altmode_status_update(struct dp_altmode *dp)
 {
 	bool configured = !!DP_CONF_GET_PIN_ASSIGN(dp->data.conf);
+	bool hpd = !!(dp->data.status & DP_STATUS_HPD_STATE);
 	u8 con = DP_STATUS_CONNECTION(dp->data.status);
 	int ret = 0;
 
@@ -137,6 +142,11 @@ static int dp_altmode_status_update(struct dp_altmode *dp)
 		ret = dp_altmode_configure(dp, con);
 		if (!ret)
 			dp->state = DP_STATE_CONFIGURE;
+	} else {
+		if (dp->hpd != hpd) {
+			drm_connector_oob_hotplug_event(dp->connector_fwnode);
+			dp->hpd = hpd;
+		}
 	}
 
 	return ret;
@@ -512,6 +522,7 @@ static const struct attribute_group dp_altmode_group = {
 int dp_altmode_probe(struct typec_altmode *alt)
 {
 	const struct typec_altmode *port = typec_altmode_get_partner(alt);
+	struct fwnode_handle *fwnode;
 	struct dp_altmode *dp;
 	int ret;
 
@@ -540,6 +551,11 @@ int dp_altmode_probe(struct typec_altmode *alt)
 	alt->desc = "DisplayPort";
 	alt->ops = &dp_altmode_ops;
 
+	fwnode = dev_fwnode(alt->dev.parent->parent); /* typec_port fwnode */
+	dp->connector_fwnode = fwnode_find_reference(fwnode, "displayport", 0);
+	if (IS_ERR(dp->connector_fwnode))
+		dp->connector_fwnode = NULL;
+
 	typec_altmode_set_drvdata(alt, dp);
 
 	dp->state = DP_STATE_ENTER;
@@ -555,6 +571,13 @@ void dp_altmode_remove(struct typec_altmode *alt)
 
 	sysfs_remove_group(&alt->dev.kobj, &dp_altmode_group);
 	cancel_work_sync(&dp->work);
+
+	if (dp->connector_fwnode) {
+		if (dp->hpd)
+			drm_connector_oob_hotplug_event(dp->connector_fwnode);
+
+		fwnode_handle_put(dp->connector_fwnode);
+	}
 }
 EXPORT_SYMBOL_GPL(dp_altmode_remove);
 
-- 
2.31.1

Re: [PATCH 7/8] usb: typec: altmodes/displayport: Make dp_altmode_notify() more generic

[Heikki Krogerus]

On Wed, May 05, 2021 at 06:24:14PM +0200, Hans de Goede wrote:
> Make dp_altmode_notify() handle the dp->data.conf == 0 case too,
> rather then having separate code-paths for this in various places
> which call it.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

> ---
>  drivers/usb/typec/altmodes/displayport.c | 35 +++++++++---------------
>  1 file changed, 13 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c
> index b7f094435b00..aa669b9cf70e 100644
> --- a/drivers/usb/typec/altmodes/displayport.c
> +++ b/drivers/usb/typec/altmodes/displayport.c
> @@ -66,10 +66,17 @@ struct dp_altmode {
>  
>  static int dp_altmode_notify(struct dp_altmode *dp)
>  {
> -	u8 state = get_count_order(DP_CONF_GET_PIN_ASSIGN(dp->data.conf));
> +	unsigned long conf;
> +	u8 state;
> +
> +	if (dp->data.conf) {
> +		state = get_count_order(DP_CONF_GET_PIN_ASSIGN(dp->data.conf));
> +		conf = TYPEC_MODAL_STATE(state);
> +	} else {
> +		conf = TYPEC_STATE_USB;
> +	}
>  
> -	return typec_altmode_notify(dp->alt, TYPEC_MODAL_STATE(state),
> -				   &dp->data);
> +	return typec_altmode_notify(dp->alt, conf, &dp->data);
>  }
>  
>  static int dp_altmode_configure(struct dp_altmode *dp, u8 con)
> @@ -137,21 +144,10 @@ static int dp_altmode_status_update(struct dp_altmode *dp)
>  
>  static int dp_altmode_configured(struct dp_altmode *dp)
>  {
> -	int ret;
> -
>  	sysfs_notify(&dp->alt->dev.kobj, "displayport", "configuration");
> -
> -	if (!dp->data.conf)
> -		return typec_altmode_notify(dp->alt, TYPEC_STATE_USB,
> -					    &dp->data);
> -
> -	ret = dp_altmode_notify(dp);
> -	if (ret)
> -		return ret;
> -
>  	sysfs_notify(&dp->alt->dev.kobj, "displayport", "pin_assignment");
>  
> -	return 0;
> +	return dp_altmode_notify(dp);
>  }
>  
>  static int dp_altmode_configure_vdm(struct dp_altmode *dp, u32 conf)
> @@ -172,13 +168,8 @@ static int dp_altmode_configure_vdm(struct dp_altmode *dp, u32 conf)
>  	}
>  
>  	ret = typec_altmode_vdm(dp->alt, header, &conf, 2);
> -	if (ret) {
> -		if (DP_CONF_GET_PIN_ASSIGN(dp->data.conf))
> -			dp_altmode_notify(dp);
> -		else
> -			typec_altmode_notify(dp->alt, TYPEC_STATE_USB,
> -					     &dp->data);
> -	}
> +	if (ret)
> +		dp_altmode_notify(dp);
>  
>  	return ret;
>  }
> -- 
> 2.31.1

-- 
heikki

Re: [PATCH 8/8] usb: typec: altmodes/displayport: Notify drm subsys of hotplug events

[Heikki Krogerus]

On Wed, May 05, 2021 at 06:24:15PM +0200, Hans de Goede wrote:
> Use the new drm_connector_oob_hotplug_event() functions to let drm/kms
> drivers know about DisplayPort over Type-C hotplug events.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

> ---
> Changes in v3:
> - Only call drm_connector_oob_hotplug_event() on hpd status bit change
> - Adjust for drm_connector_oob_hotplug_event() no longer having a data
>   argument
> 
> Changes in v2:
> - Add missing depends on DRM to TYPEC_DP_ALTMODE Kconfig entry
> ---
>  drivers/usb/typec/altmodes/Kconfig       |  1 +
>  drivers/usb/typec/altmodes/displayport.c | 23 +++++++++++++++++++++++
>  2 files changed, 24 insertions(+)
> 
> diff --git a/drivers/usb/typec/altmodes/Kconfig b/drivers/usb/typec/altmodes/Kconfig
> index 60d375e9c3c7..1a6b5e872b0d 100644
> --- a/drivers/usb/typec/altmodes/Kconfig
> +++ b/drivers/usb/typec/altmodes/Kconfig
> @@ -4,6 +4,7 @@ menu "USB Type-C Alternate Mode drivers"
>  
>  config TYPEC_DP_ALTMODE
>  	tristate "DisplayPort Alternate Mode driver"
> +	depends on DRM
>  	help
>  	  DisplayPort USB Type-C Alternate Mode allows DisplayPort
>  	  displays and adapters to be attached to the USB Type-C
> diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c
> index aa669b9cf70e..c1d8c23baa39 100644
> --- a/drivers/usb/typec/altmodes/displayport.c
> +++ b/drivers/usb/typec/altmodes/displayport.c
> @@ -11,8 +11,10 @@
>  #include <linux/delay.h>
>  #include <linux/mutex.h>
>  #include <linux/module.h>
> +#include <linux/property.h>
>  #include <linux/usb/pd_vdo.h>
>  #include <linux/usb/typec_dp.h>
> +#include <drm/drm_connector.h>
>  #include "displayport.h"
>  
>  #define DP_HEADER(_dp, ver, cmd)	(VDO((_dp)->alt->svid, 1, ver, cmd)	\
> @@ -57,11 +59,13 @@ struct dp_altmode {
>  	struct typec_displayport_data data;
>  
>  	enum dp_state state;
> +	bool hpd;
>  
>  	struct mutex lock; /* device lock */
>  	struct work_struct work;
>  	struct typec_altmode *alt;
>  	const struct typec_altmode *port;
> +	struct fwnode_handle *connector_fwnode;
>  };
>  
>  static int dp_altmode_notify(struct dp_altmode *dp)
> @@ -125,6 +129,7 @@ static int dp_altmode_configure(struct dp_altmode *dp, u8 con)
>  static int dp_altmode_status_update(struct dp_altmode *dp)
>  {
>  	bool configured = !!DP_CONF_GET_PIN_ASSIGN(dp->data.conf);
> +	bool hpd = !!(dp->data.status & DP_STATUS_HPD_STATE);
>  	u8 con = DP_STATUS_CONNECTION(dp->data.status);
>  	int ret = 0;
>  
> @@ -137,6 +142,11 @@ static int dp_altmode_status_update(struct dp_altmode *dp)
>  		ret = dp_altmode_configure(dp, con);
>  		if (!ret)
>  			dp->state = DP_STATE_CONFIGURE;
> +	} else {
> +		if (dp->hpd != hpd) {
> +			drm_connector_oob_hotplug_event(dp->connector_fwnode);
> +			dp->hpd = hpd;
> +		}
>  	}
>  
>  	return ret;
> @@ -512,6 +522,7 @@ static const struct attribute_group dp_altmode_group = {
>  int dp_altmode_probe(struct typec_altmode *alt)
>  {
>  	const struct typec_altmode *port = typec_altmode_get_partner(alt);
> +	struct fwnode_handle *fwnode;
>  	struct dp_altmode *dp;
>  	int ret;
>  
> @@ -540,6 +551,11 @@ int dp_altmode_probe(struct typec_altmode *alt)
>  	alt->desc = "DisplayPort";
>  	alt->ops = &dp_altmode_ops;
>  
> +	fwnode = dev_fwnode(alt->dev.parent->parent); /* typec_port fwnode */
> +	dp->connector_fwnode = fwnode_find_reference(fwnode, "displayport", 0);
> +	if (IS_ERR(dp->connector_fwnode))
> +		dp->connector_fwnode = NULL;
> +
>  	typec_altmode_set_drvdata(alt, dp);
>  
>  	dp->state = DP_STATE_ENTER;
> @@ -555,6 +571,13 @@ void dp_altmode_remove(struct typec_altmode *alt)
>  
>  	sysfs_remove_group(&alt->dev.kobj, &dp_altmode_group);
>  	cancel_work_sync(&dp->work);
> +
> +	if (dp->connector_fwnode) {
> +		if (dp->hpd)
> +			drm_connector_oob_hotplug_event(dp->connector_fwnode);
> +
> +		fwnode_handle_put(dp->connector_fwnode);
> +	}
>  }
>  EXPORT_SYMBOL_GPL(dp_altmode_remove);
>  
> -- 
> 2.31.1

-- 
heikki

Re: [PATCH 0/8] drm + usb-type-c: Add support for out-of-band hotplug notification (v3)

[Heikki Krogerus]

On Wed, May 05, 2021 at 06:24:07PM +0200, Hans de Goede wrote:
> Hi All,
> 
> Here is v3 of my patchset making DP over Type-C work on devices where the
> Type-C controller does not drive the HPD pin on the GPU, but instead
> we need to forward HPD events from the Type-C controller to the DRM driver.

These look good to me. I can also test these next week if needed. I'll
give my Tested-by tag after that if these haven't been taken by
anybody by that.


thanks,

-- 
heikki

Re: [PATCH 0/8] drm + usb-type-c: Add support for out-of-band hotplug notification (v3)

[Heikki Krogerus]

On Tue, May 11, 2021 at 10:05:26AM +0300, Heikki Krogerus wrote:
> On Wed, May 05, 2021 at 06:24:07PM +0200, Hans de Goede wrote:
> > Hi All,
> > 
> > Here is v3 of my patchset making DP over Type-C work on devices where the
> > Type-C controller does not drive the HPD pin on the GPU, but instead
> > we need to forward HPD events from the Type-C controller to the DRM driver.
> 
> These look good to me. I can also test these next week if needed. I'll
> give my Tested-by tag after that if these haven't been taken by
> anybody by that.

It's almost weird to see console output from the Type-C connector on
my good old GPD printed to an actual display :-)

At least in my tests, the DP alt mode driver now calls
drm_connector_oob_hotplug_event() only when it should. This is pretty cool!
FWIW:

Tested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>


thanks,

-- 
heikki

[PATCH 6/8] drm/i915/dp: Add support for out-of-bound hotplug events

[Hans de Goede]

On some Cherry Trail devices, DisplayPort over Type-C is supported through
a USB-PD microcontroller (e.g. a fusb302) + a mux to switch the superspeed
datalines between USB-3 and DP (e.g. a pi3usb30532). The kernel in this
case does the PD/alt-mode negotiation itself, rather then everything being
handled in firmware.

So the kernel itself picks an alt-mode, tells the Type-C "dongle" to switch
to DP mode and sets the mux accordingly. In this setup the HPD pin is not
connected, so the i915 driver needs to respond to a software event and scan
the DP port for changes manually.

This commit adds support for this. Together with the recent addition of
DP alt-mode support to the Type-C subsystem this makes DP over Type-C
work on these devices.

Tested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 75d4ebc66941..e807ffc2d782 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -4590,6 +4590,17 @@ static int intel_dp_connector_atomic_check(struct drm_connector *conn,
 	return intel_modeset_synced_crtcs(state, conn);
 }
 
+static void intel_dp_oob_hotplug_event(struct drm_connector *connector)
+{
+	struct intel_encoder *encoder = intel_attached_encoder(to_intel_connector(connector));
+	struct drm_i915_private *i915 = to_i915(connector->dev);
+
+	spin_lock_irq(&i915->irq_lock);
+	i915->hotplug.event_bits |= BIT(encoder->hpd_pin);
+	spin_unlock_irq(&i915->irq_lock);
+	queue_delayed_work(system_wq, &i915->hotplug.hotplug_work, 0);
+}
+
 static const struct drm_connector_funcs intel_dp_connector_funcs = {
 	.force = intel_dp_force,
 	.fill_modes = drm_helper_probe_single_connector_modes,
@@ -4600,6 +4611,7 @@ static const struct drm_connector_funcs intel_dp_connector_funcs = {
 	.destroy = intel_connector_destroy,
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 	.atomic_duplicate_state = intel_digital_connector_duplicate_state,
+	.oob_hotplug_event = intel_dp_oob_hotplug_event,
 };
 
 static const struct drm_connector_helper_funcs intel_dp_connector_helper_funcs = {
-- 
2.31.1

[PATCH 6/8] drm/i915/dp: Add support for out-of-bound hotplug events

[Hans de Goede]

On some Cherry Trail devices, DisplayPort over Type-C is supported through
a USB-PD microcontroller (e.g. a fusb302) + a mux to switch the superspeed
datalines between USB-3 and DP (e.g. a pi3usb30532). The kernel in this
case does the PD/alt-mode negotiation itself, rather then everything being
handled in firmware.

So the kernel itself picks an alt-mode, tells the Type-C "dongle" to switch
to DP mode and sets the mux accordingly. In this setup the HPD pin is not
connected, so the i915 driver needs to respond to a software event and scan
the DP port for changes manually.

This commit adds support for this. Together with the recent addition of
DP alt-mode support to the Type-C subsystem this makes DP over Type-C
work on these devices.

Tested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 5c9222283044..5d6cf2657fa3 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -4598,6 +4598,17 @@ static int intel_dp_connector_atomic_check(struct drm_connector *conn,
 	return intel_modeset_synced_crtcs(state, conn);
 }
 
+static void intel_dp_oob_hotplug_event(struct drm_connector *connector)
+{
+	struct intel_encoder *encoder = intel_attached_encoder(to_intel_connector(connector));
+	struct drm_i915_private *i915 = to_i915(connector->dev);
+
+	spin_lock_irq(&i915->irq_lock);
+	i915->hotplug.event_bits |= BIT(encoder->hpd_pin);
+	spin_unlock_irq(&i915->irq_lock);
+	queue_delayed_work(system_wq, &i915->hotplug.hotplug_work, 0);
+}
+
 static const struct drm_connector_funcs intel_dp_connector_funcs = {
 	.force = intel_dp_force,
 	.fill_modes = drm_helper_probe_single_connector_modes,
@@ -4608,6 +4619,7 @@ static const struct drm_connector_funcs intel_dp_connector_funcs = {
 	.destroy = intel_connector_destroy,
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 	.atomic_duplicate_state = intel_digital_connector_duplicate_state,
+	.oob_hotplug_event = intel_dp_oob_hotplug_event,
 };
 
 static const struct drm_connector_helper_funcs intel_dp_connector_helper_funcs = {
-- 
2.31.1