Adding upstream version 6.8.9.upstream/6.8.9

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 203 insertions, 0 deletions

diff --git a/drivers/gpu/drm/bridge/aux-hpd-bridge.c b/drivers/gpu/drm/bridge/aux-hpd-bridge.c
new file mode 100644
index 0000000000..6886db2d9e
--- /dev/null
+++ b/drivers/gpu/drm/bridge/aux-hpd-bridge.c
@@ -0,0 +1,203 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2023 Linaro Ltd.
+ *
+ * Author: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
+ */
+#include <linux/auxiliary_bus.h>
+#include <linux/module.h>
+#include <linux/of.h>
+
+#include <drm/drm_bridge.h>
+#include <drm/bridge/aux-bridge.h>
+
+static DEFINE_IDA(drm_aux_hpd_bridge_ida);
+
+struct drm_aux_hpd_bridge_data {
+	struct drm_bridge bridge;
+	struct device *dev;
+};
+
+static void drm_aux_hpd_bridge_release(struct device *dev)
+{
+	struct auxiliary_device *adev = to_auxiliary_dev(dev);
+
+	ida_free(&drm_aux_hpd_bridge_ida, adev->id);
+
+	of_node_put(adev->dev.platform_data);
+	of_node_put(adev->dev.of_node);
+
+	kfree(adev);
+}
+
+static void drm_aux_hpd_bridge_free_adev(void *_adev)
+{
+	auxiliary_device_uninit(_adev);
+}
+
+/**
+ * devm_drm_dp_hpd_bridge_alloc - allocate a HPD DisplayPort bridge
+ * @parent: device instance providing this bridge
+ * @np: device node pointer corresponding to this bridge instance
+ *
+ * Creates a simple DRM bridge with the type set to
+ * DRM_MODE_CONNECTOR_DisplayPort, which terminates the bridge chain and is
+ * able to send the HPD events.
+ *
+ * Return: bridge auxiliary device pointer or an error pointer
+ */
+struct auxiliary_device *devm_drm_dp_hpd_bridge_alloc(struct device *parent, struct device_node *np)
+{
+	struct auxiliary_device *adev;
+	int ret;
+
+	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
+	if (!adev)
+		return ERR_PTR(-ENOMEM);
+
+	ret = ida_alloc(&drm_aux_hpd_bridge_ida, GFP_KERNEL);
+	if (ret < 0) {
+		kfree(adev);
+		return ERR_PTR(ret);
+	}
+
+	adev->id = ret;
+	adev->name = "dp_hpd_bridge";
+	adev->dev.parent = parent;
+	adev->dev.of_node = of_node_get(parent->of_node);
+	adev->dev.release = drm_aux_hpd_bridge_release;
+	adev->dev.platform_data = of_node_get(np);
+
+	ret = auxiliary_device_init(adev);
+	if (ret) {
+		of_node_put(adev->dev.platform_data);
+		of_node_put(adev->dev.of_node);
+		ida_free(&drm_aux_hpd_bridge_ida, adev->id);
+		kfree(adev);
+		return ERR_PTR(ret);
+	}
+
+	ret = devm_add_action_or_reset(parent, drm_aux_hpd_bridge_free_adev, adev);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return adev;
+}
+EXPORT_SYMBOL_GPL(devm_drm_dp_hpd_bridge_alloc);
+
+static void drm_aux_hpd_bridge_del_adev(void *_adev)
+{
+	auxiliary_device_delete(_adev);
+}
+
+/**
+ * devm_drm_dp_hpd_bridge_add - register a HDP DisplayPort bridge
+ * @dev: struct device to tie registration lifetime to
+ * @adev: bridge auxiliary device to be registered
+ *
+ * Returns: zero on success or a negative errno
+ */
+int devm_drm_dp_hpd_bridge_add(struct device *dev, struct auxiliary_device *adev)
+{
+	int ret;
+
+	ret = auxiliary_device_add(adev);
+	if (ret)
+		return ret;
+
+	return devm_add_action_or_reset(dev, drm_aux_hpd_bridge_del_adev, adev);
+}
+EXPORT_SYMBOL_GPL(devm_drm_dp_hpd_bridge_add);
+
+/**
+ * drm_dp_hpd_bridge_register - allocate and register a HDP DisplayPort bridge
+ * @parent: device instance providing this bridge
+ * @np: device node pointer corresponding to this bridge instance
+ *
+ * Return: device instance that will handle created bridge or an error pointer
+ */
+struct device *drm_dp_hpd_bridge_register(struct device *parent, struct device_node *np)
+{
+	struct auxiliary_device *adev;
+	int ret;
+
+	adev = devm_drm_dp_hpd_bridge_alloc(parent, np);
+	if (IS_ERR(adev))
+		return ERR_CAST(adev);
+
+	ret = devm_drm_dp_hpd_bridge_add(parent, adev);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return &adev->dev;
+}
+EXPORT_SYMBOL_GPL(drm_dp_hpd_bridge_register);
+
+/**
+ * drm_aux_hpd_bridge_notify - notify hot plug detection events
+ * @dev: device created for the HPD bridge
+ * @status: output connection status
+ *
+ * A wrapper around drm_bridge_hpd_notify() that is used to report hot plug
+ * detection events for bridges created via drm_dp_hpd_bridge_register().
+ *
+ * This function shall be called in a context that can sleep.
+ */
+void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status)
+{
+	struct auxiliary_device *adev = to_auxiliary_dev(dev);
+	struct drm_aux_hpd_bridge_data *data = auxiliary_get_drvdata(adev);
+
+	if (!data)
+		return;
+
+	drm_bridge_hpd_notify(&data->bridge, status);
+}
+EXPORT_SYMBOL_GPL(drm_aux_hpd_bridge_notify);
+
+static int drm_aux_hpd_bridge_attach(struct drm_bridge *bridge,
+				     enum drm_bridge_attach_flags flags)
+{
+	return flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR ? 0 : -EINVAL;
+}
+
+static const struct drm_bridge_funcs drm_aux_hpd_bridge_funcs = {
+	.attach	= drm_aux_hpd_bridge_attach,
+};
+
+static int drm_aux_hpd_bridge_probe(struct auxiliary_device *auxdev,
+				    const struct auxiliary_device_id *id)
+{
+	struct drm_aux_hpd_bridge_data *data;
+
+	data = devm_kzalloc(&auxdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->dev = &auxdev->dev;
+	data->bridge.funcs = &drm_aux_hpd_bridge_funcs;
+	data->bridge.of_node = dev_get_platdata(data->dev);
+	data->bridge.ops = DRM_BRIDGE_OP_HPD;
+	data->bridge.type = id->driver_data;
+
+	auxiliary_set_drvdata(auxdev, data);
+
+	return devm_drm_bridge_add(data->dev, &data->bridge);
+}
+
+static const struct auxiliary_device_id drm_aux_hpd_bridge_table[] = {
+	{ .name = KBUILD_MODNAME ".dp_hpd_bridge", .driver_data = DRM_MODE_CONNECTOR_DisplayPort, },
+	{},
+};
+MODULE_DEVICE_TABLE(auxiliary, drm_aux_hpd_bridge_table);
+
+static struct auxiliary_driver drm_aux_hpd_bridge_drv = {
+	.name = "aux_hpd_bridge",
+	.id_table = drm_aux_hpd_bridge_table,
+	.probe = drm_aux_hpd_bridge_probe,
+};
+module_auxiliary_driver(drm_aux_hpd_bridge_drv);
+
+MODULE_AUTHOR("Dmitry Baryshkov <dmitry.baryshkov@linaro.org>");
+MODULE_DESCRIPTION("DRM HPD bridge");
+MODULE_LICENSE("GPL");