[PATCH RFC v2 09/16] drm/vkms: Introduce configfs for connectors

[Louis Chauvet <louis.chauvet@bootlin.com>]

Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
---
 drivers/gpu/drm/vkms/vkms_config.c   |  13 ++++
 drivers/gpu/drm/vkms/vkms_config.h   |   3 +
 drivers/gpu/drm/vkms/vkms_configfs.c | 138 +++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/vkms/vkms_configfs.h |  23 ++++++
 4 files changed, 177 insertions(+)

diff --git a/drivers/gpu/drm/vkms/vkms_config.c b/drivers/gpu/drm/vkms/vkms_config.c
index 9a461a0481c2a20d6d48f1aa9649843ad1b7d13d..da99785ec89f0c6a7fe1a71fd2e6f5944c844aa9 100644
--- a/drivers/gpu/drm/vkms/vkms_config.c
+++ b/drivers/gpu/drm/vkms/vkms_config.c
@@ -516,6 +516,19 @@ vkms_config_connector_attach_encoder(struct vkms_config_connector *vkms_config_c
 	return ret;
 }
 
+void vkms_config_connector_detach_encoder(struct vkms_config_connector *vkms_config_connector,
+					  struct vkms_config_encoder *vkms_config_encoder)
+{
+	struct vkms_config_encoder *encoder_entry;
+	unsigned long encoder_idx;
+
+	xa_for_each(&vkms_config_connector->possible_encoders, encoder_idx, encoder_entry) {
+		if (encoder_entry == vkms_config_encoder)
+			break;
+	}
+	xa_erase(&vkms_config_connector->possible_encoders, encoder_idx);
+}
+
 bool vkms_config_is_valid(struct vkms_config *config)
 {
 	struct vkms_config_plane *config_plane;
diff --git a/drivers/gpu/drm/vkms/vkms_config.h b/drivers/gpu/drm/vkms/vkms_config.h
index 529d9c99f3c406d49dc7f3689a84c3dd775399a9..b1d80185216798cc9fc06e7d1cd0c423b7275185 100644
--- a/drivers/gpu/drm/vkms/vkms_config.h
+++ b/drivers/gpu/drm/vkms/vkms_config.h
@@ -197,6 +197,9 @@ int __must_check vkms_config_encoder_attach_crtc(struct vkms_config_encoder *vkm
 int __must_check
 vkms_config_connector_attach_encoder(struct vkms_config_connector *vkms_config_connector,
 				     struct vkms_config_encoder *vkms_config_encoder);
+void vkms_config_connector_detach_encoder(struct vkms_config_connector *vkms_config_connector,
+					  struct vkms_config_encoder *vkms_config_encoder);
+
 /**
  * vkms_config_delete_plane() - Remove a plane configuration and frees its memory
  *
diff --git a/drivers/gpu/drm/vkms/vkms_configfs.c b/drivers/gpu/drm/vkms/vkms_configfs.c
index a410c9be4f2bbf7b2651245747eb357fcf32d1f2..94c288514172b88d06c2b74e36569c6d55383782 100644
--- a/drivers/gpu/drm/vkms/vkms_configfs.c
+++ b/drivers/gpu/drm/vkms/vkms_configfs.c
@@ -746,6 +746,7 @@ static struct config_group *encoder_make_group(struct config_group *config_group
 	}
 
 	strscpy(vkms_configfs_encoder->vkms_config_encoder->name, name, strlen(name) + 1);
+
 	config_group_init_type_name(&vkms_configfs_encoder->group, name,
 				    &encoder_item_type);
 
@@ -769,6 +770,139 @@ static const struct config_item_type encoders_item_type = {
 	.ct_owner	= THIS_MODULE,
 };
 
+static int connector_possible_encoders_allow_link(struct config_item *src,
+						  struct config_item *target)
+{
+	struct vkms_config_encoder *vkms_config_encoder;
+	struct vkms_configfs_device *vkms_configfs =
+		connector_possible_encoder_src_item_to_vkms_configfs_device
+		(src);
+
+	mutex_lock(&vkms_configfs->lock);
+
+	if (target->ci_type != &encoder_item_type) {
+		DRM_ERROR("Unable to link non-CRTCs.\n");
+		mutex_unlock(&vkms_configfs->lock);
+		return -EINVAL;
+	}
+
+	vkms_config_encoder = encoder_item_to_vkms_configfs_encoder(target)
+				      ->vkms_config_encoder;
+	struct vkms_config_connector *vkms_config_connector =
+		connector_possible_encoder_src_item_to_vkms_configfs_connector
+		(src)
+			->vkms_config_connector;
+
+	if (vkms_config_connector_attach_encoder(vkms_config_connector,
+						 vkms_config_encoder))
+		return -EINVAL;
+
+	mutex_unlock(&vkms_configfs->lock);
+
+	return 0;
+}
+
+static void connector_possible_encoders_drop_link(struct config_item *src,
+						  struct config_item *target)
+{
+	struct vkms_config_encoder *vkms_config_encoder;
+	struct vkms_configfs_device *vkms_configfs =
+		connector_possible_encoder_src_item_to_vkms_configfs_device(src);
+
+	mutex_lock(&vkms_configfs->lock);
+
+	vkms_config_encoder = encoder_item_to_vkms_configfs_encoder(target)->vkms_config_encoder;
+	struct vkms_config_connector *vkms_config_connector =
+		connector_possible_encoder_src_item_to_vkms_configfs_connector(src)
+			->vkms_config_connector;
+
+	vkms_config_connector_detach_encoder(vkms_config_connector, vkms_config_encoder);
+
+	mutex_unlock(&vkms_configfs->lock);
+}
+
+static struct configfs_item_operations connector_possible_encoders_item_operations = {
+	.allow_link = &connector_possible_encoders_allow_link,
+	.drop_link = &connector_possible_encoders_drop_link,
+};
+
+static struct config_item_type connector_possible_encoders_item_type = {
+	.ct_item_ops = &connector_possible_encoders_item_operations,
+	.ct_owner = THIS_MODULE,
+};
+
+static void connector_release(struct config_item *item)
+{
+	struct vkms_configfs_connector *vkms_configfs_connector =
+		connector_item_to_vkms_configfs_connector(item);
+
+	mutex_lock(&vkms_configfs_connector->vkms_configfs_device->lock);
+	vkms_config_delete_connector(vkms_configfs_connector->vkms_config_connector);
+	mutex_unlock(&vkms_configfs_connector->vkms_configfs_device->lock);
+
+	kfree(vkms_configfs_connector);
+}
+
+static struct configfs_item_operations connector_item_operations = {
+	.release = connector_release,
+};
+
+static const struct config_item_type connector_item_type = {
+	.ct_item_ops = &connector_item_operations,
+	.ct_owner = THIS_MODULE,
+};
+
+static struct config_group *connector_make_group(struct config_group *config_group,
+						 const char *name)
+{
+	struct vkms_configfs_device *vkms_configfs =
+		connector_item_to_vkms_configfs_device(&config_group->cg_item);
+	struct vkms_configfs_connector *vkms_configfs_connector;
+
+	vkms_configfs_connector = kzalloc(sizeof(*vkms_configfs_connector), GFP_KERNEL);
+
+	if (!vkms_configfs_connector)
+		return ERR_PTR(-ENOMEM);
+
+	mutex_lock(&vkms_configfs->lock);
+
+	if (vkms_configfs->enabled) {
+		kfree(vkms_configfs_connector);
+		mutex_unlock(&vkms_configfs->lock);
+		return ERR_PTR(-EINVAL);
+	}
+
+	vkms_configfs_connector->vkms_config_connector =
+		vkms_config_create_connector(vkms_configfs->vkms_config);
+
+	if (!vkms_configfs_connector->vkms_config_connector) {
+		kfree(vkms_configfs_connector);
+		mutex_unlock(&vkms_configfs->lock);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	config_group_init_type_name(&vkms_configfs_connector->group, name, &connector_item_type);
+
+	config_group_init_type_name(&vkms_configfs_connector->possible_encoder_group,
+				    "possible_encoders", &connector_possible_encoders_item_type);
+	configfs_add_default_group(&vkms_configfs_connector->possible_encoder_group,
+				   &vkms_configfs_connector->group);
+	vkms_configfs_connector->vkms_configfs_device = vkms_configfs;
+
+	mutex_unlock(&vkms_configfs->lock);
+
+	return &vkms_configfs_connector->group;
+}
+
+static struct configfs_group_operations connector_group_operations = {
+	.make_group = &connector_make_group,
+};
+
+static const struct config_item_type connectors_item_type = {
+	.ct_group_ops = &connector_group_operations,
+	.ct_owner = THIS_MODULE,
+};
+
 /**
  * configfs_lock_dependencies() - In order to forbid the userspace to delete items when the
  * device is enabled, mark all configfs items as dependent
@@ -915,6 +1049,10 @@ static struct config_group *root_make_group(struct config_group *group,
 	config_group_init_type_name(&configfs->encoder_group, "encoders", &encoders_item_type);
 	configfs_add_default_group(&configfs->encoder_group, &configfs->group);
 
+	config_group_init_type_name(&configfs->connector_group, "connectors",
+				    &connectors_item_type);
+	configfs_add_default_group(&configfs->connector_group, &configfs->group);
+
 	return &configfs->group;
 }
 
diff --git a/drivers/gpu/drm/vkms/vkms_configfs.h b/drivers/gpu/drm/vkms/vkms_configfs.h
index df743e0107f40cd10433bdb638108d266f9c83a6..12c0fdefb813387515d144519479c242b7ef6728 100644
--- a/drivers/gpu/drm/vkms/vkms_configfs.h
+++ b/drivers/gpu/drm/vkms/vkms_configfs.h
@@ -22,6 +22,7 @@ struct vkms_configfs_device {
 	struct config_group plane_group;
 	struct config_group crtc_group;
 	struct config_group encoder_group;
+	struct config_group connector_group;
 
 	struct mutex lock;
 	bool enabled;
@@ -53,6 +54,14 @@ struct vkms_configfs_encoder {
 	struct vkms_config_encoder *vkms_config_encoder;
 };
 
+struct vkms_configfs_connector {
+	struct config_group group;
+
+	struct config_group possible_encoder_group;
+	struct vkms_configfs_device *vkms_configfs_device;
+	struct vkms_config_connector *vkms_config_connector;
+};
+
 #define config_item_to_vkms_configfs_device(item) \
 	container_of(to_config_group((item)), struct vkms_configfs_device, group)
 
@@ -68,6 +77,9 @@ struct vkms_configfs_encoder {
 #define encoder_item_to_vkms_configfs_encoder(item) \
 	container_of(to_config_group((item)), struct vkms_configfs_encoder, group)
 
+#define connector_item_to_vkms_configfs_connector(item) \
+	container_of(to_config_group((item)), struct vkms_configfs_connector, group)
+
 #define plane_item_to_vkms_configfs_device(item) \
 	planes_item_to_vkms_configfs_device((item)->ci_parent)
 
@@ -89,14 +101,25 @@ struct vkms_configfs_encoder {
 #define encoder_item_to_vkms_configfs_device(item) \
 	config_item_to_vkms_configfs_device((item)->ci_parent)
 
+#define connector_item_to_vkms_configfs_device(item) \
+	config_item_to_vkms_configfs_device((item)->ci_parent)
+
 #define encoder_child_item_to_vkms_configfs_device(item) \
 	encoder_item_to_vkms_configfs_device((item)->ci_parent)
 
 #define encoder_possible_crtc_src_item_to_vkms_configfs_device(item) \
 	encoder_child_item_to_vkms_configfs_device((item)->ci_parent)
 
+#define connector_child_item_to_vkms_configfs_device(item) \
+	connector_item_to_vkms_configfs_device((item)->ci_parent)
+
+#define connector_possible_encoder_src_item_to_vkms_configfs_device(item) \
+	connector_child_item_to_vkms_configfs_device((item)->ci_parent)
+
 #define encoder_possible_crtc_src_item_to_vkms_configfs_encoder(item) \
 	encoder_item_to_vkms_configfs_encoder((item)->ci_parent)
+#define connector_possible_encoder_src_item_to_vkms_configfs_connector(item) \
+	connector_item_to_vkms_configfs_connector((item)->ci_parent)
 
 /* ConfigFS Support */
 int vkms_init_configfs(void);

-- 
2.47.0