diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 59771412686b..6c3cad894648 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -2444,7 +2444,8 @@ static int acpi_walk_dep_device_list(acpi_handle handle,
  */
 void acpi_dev_clear_dependencies(struct acpi_device *supplier)
 {
-	acpi_walk_dep_device_list(supplier->handle, acpi_scan_clear_dep, NULL);
+	if (supplier)
+		acpi_walk_dep_device_list(supplier->handle, acpi_scan_clear_dep, NULL);
 }
 EXPORT_SYMBOL_GPL(acpi_dev_clear_dependencies);
 
diff --git a/drivers/platform/surface/aggregator/bus.c b/drivers/platform/surface/aggregator/bus.c
index af8d573aae93..d68d231e716e 100644
--- a/drivers/platform/surface/aggregator/bus.c
+++ b/drivers/platform/surface/aggregator/bus.c
@@ -6,6 +6,7 @@
  */
 
 #include <linux/device.h>
+#include <linux/of.h>
 #include <linux/property.h>
 #include <linux/slab.h>
 
@@ -441,6 +442,7 @@ static int ssam_add_client_device(struct device *parent, struct ssam_controller
 
 	sdev->dev.parent = parent;
 	sdev->dev.fwnode = fwnode_handle_get(node);
+	sdev->dev.of_node = to_of_node(node);
 
 	status = ssam_device_add(sdev);
 	if (status)
diff --git a/drivers/platform/surface/aggregator/controller.c b/drivers/platform/surface/aggregator/controller.c
index 7fc602e01487..aea10e192140 100644
--- a/drivers/platform/surface/aggregator/controller.c
+++ b/drivers/platform/surface/aggregator/controller.c
@@ -1104,13 +1104,6 @@ int ssam_controller_caps_load_from_acpi(acpi_handle handle,
 	u64 funcs;
 	int status;
 
-	/* Set defaults. */
-	caps->ssh_power_profile = U32_MAX;
-	caps->screen_on_sleep_idle_timeout = U32_MAX;
-	caps->screen_off_sleep_idle_timeout = U32_MAX;
-	caps->d3_closes_handle = false;
-	caps->ssh_buffer_size = U32_MAX;
-
 	/* Pre-load supported DSM functions. */
 	status = ssam_dsm_get_functions(handle, &funcs);
 	if (status)
@@ -1149,6 +1142,57 @@ int ssam_controller_caps_load_from_acpi(acpi_handle handle,
 	return 0;
 }
 
+/**
+ * ssam_controller_caps_load_from_of() - Load controller capabilities from OF/DT.
+ * @device: The device from which to load the capabilities from.
+ * @caps:   Where to store the capabilities in.
+ *
+ * Return: Returns zero on success, a negative error code on failure.
+ */
+static int ssam_controller_caps_load_from_of(struct device *dev, struct ssam_controller_caps *caps)
+{
+	/*
+	 * Every device starting with Surface Pro X through Laptop 7 uses these
+	 * identical values, which makes them good defaults.
+	 */
+	caps->d3_closes_handle = true;
+	caps->screen_on_sleep_idle_timeout = 5000;
+	caps->screen_off_sleep_idle_timeout = 30;
+	caps->ssh_buffer_size = 48;
+	/* TODO: figure out power profile */
+
+	return 0;
+}
+
+/**
+ * ssam_controller_caps_load_from_acpi() - Load controller capabilities from
+ * ACPI _DSM.
+ * @handle: The handle of the ACPI controller/SSH device.
+ * @caps:   Where to store the capabilities in.
+ *
+ * Initializes the given controller capabilities with default values, then
+ * checks and, if the respective _DSM functions are available, loads the
+ * actual capabilities from the _DSM.
+ *
+ * Return: Returns zero on success, a negative error code on failure.
+ */
+static int ssam_controller_caps_load(struct device *dev, struct ssam_controller_caps *caps)
+{
+	acpi_handle handle = ACPI_HANDLE(dev);
+
+	/* Set defaults. */
+	caps->ssh_power_profile = U32_MAX;
+	caps->screen_on_sleep_idle_timeout = U32_MAX;
+	caps->screen_off_sleep_idle_timeout = U32_MAX;
+	caps->d3_closes_handle = false;
+	caps->ssh_buffer_size = U32_MAX;
+
+	if (handle)
+		return ssam_controller_caps_load_from_acpi(handle, caps);
+	else
+		return ssam_controller_caps_load_from_of(dev, caps);
+}
+
 /**
  * ssam_controller_init() - Initialize SSAM controller.
  * @ctrl:   The controller to initialize.
@@ -1165,13 +1209,12 @@ int ssam_controller_caps_load_from_acpi(acpi_handle handle,
 int ssam_controller_init(struct ssam_controller *ctrl,
 			 struct serdev_device *serdev)
 {
-	acpi_handle handle = ACPI_HANDLE(&serdev->dev);
 	int status;
 
 	init_rwsem(&ctrl->lock);
 	kref_init(&ctrl->kref);
 
-	status = ssam_controller_caps_load_from_acpi(handle, &ctrl->caps);
+	status = ssam_controller_caps_load(&serdev->dev, &ctrl->caps);
 	if (status)
 		return status;
 
@@ -2715,11 +2758,12 @@ int ssam_irq_setup(struct ssam_controller *ctrl)
 	const int irqf = IRQF_ONESHOT | IRQF_TRIGGER_RISING | IRQF_NO_AUTOEN;
 
 	gpiod = gpiod_get(dev, "ssam_wakeup-int", GPIOD_ASIS);
-	if (IS_ERR(gpiod))
-		return PTR_ERR(gpiod);
-
-	irq = gpiod_to_irq(gpiod);
-	gpiod_put(gpiod);
+	if (IS_ERR(gpiod)) {
+		irq = fwnode_irq_get(dev_fwnode(dev), 0);
+	} else {
+		irq = gpiod_to_irq(gpiod);
+		gpiod_put(gpiod);
+	}
 
 	if (irq < 0)
 		return irq;
diff --git a/drivers/platform/surface/aggregator/core.c b/drivers/platform/surface/aggregator/core.c
index 797d0645bd77..d39e0d7ce92b 100644
--- a/drivers/platform/surface/aggregator/core.c
+++ b/drivers/platform/surface/aggregator/core.c
@@ -17,9 +17,12 @@
 #include <linux/kernel.h>
 #include <linux/kref.h>
 #include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
 #include <linux/pm.h>
 #include <linux/serdev.h>
 #include <linux/sysfs.h>
+#include <linux/units.h>
 
 #include <linux/surface_aggregator/controller.h>
 #include <linux/surface_aggregator/device.h>
@@ -299,7 +302,7 @@ static const struct attribute_group ssam_sam_group = {
 };
 
 
-/* -- ACPI based device setup. ---------------------------------------------- */
+/* -- Serial device setup. ---------------------------------------------- */
 
 static acpi_status ssam_serdev_setup_via_acpi_crs(struct acpi_resource *rsc,
 						  void *ctx)
@@ -352,13 +355,28 @@ static acpi_status ssam_serdev_setup_via_acpi_crs(struct acpi_resource *rsc,
 	return AE_CTRL_TERMINATE;
 }
 
-static acpi_status ssam_serdev_setup_via_acpi(acpi_handle handle,
-					      struct serdev_device *serdev)
+static int ssam_serdev_setup_via_acpi(struct serdev_device *serdev, acpi_handle handle)
 {
-	return acpi_walk_resources(handle, METHOD_NAME__CRS,
-				   ssam_serdev_setup_via_acpi_crs, serdev);
+	acpi_status status;
+
+	status = acpi_walk_resources(handle, METHOD_NAME__CRS,
+				     ssam_serdev_setup_via_acpi_crs, serdev);
+
+	return status ? -ENXIO : 0;
 }
 
+static int ssam_serdev_setup(struct acpi_device *ssh, struct serdev_device *serdev)
+{
+	if (ssh)
+		return ssam_serdev_setup_via_acpi(serdev, ssh->handle);
+
+	/* TODO: these values may differ per board/implementation */
+	serdev_device_set_baudrate(serdev, 4 * HZ_PER_MHZ);
+	serdev_device_set_flow_control(serdev, true);
+	serdev_device_set_parity(serdev, SERDEV_PARITY_NONE);
+
+	return 0;
+}
 
 /* -- Power management. ----------------------------------------------------- */
 
@@ -624,13 +642,15 @@ static int ssam_serial_hub_probe(struct serdev_device *serdev)
 	acpi_status astatus;
 	int status;
 
-	status = gpiod_count(dev, NULL);
-	if (status < 0)
-		return dev_err_probe(dev, status, "no GPIO found\n");
+	if (ssh) {
+		status = gpiod_count(dev, NULL);
+		if (status < 0)
+			return dev_err_probe(dev, status, "no GPIO found\n");
 
-	status = devm_acpi_dev_add_driver_gpios(dev, ssam_acpi_gpios);
-	if (status)
-		return status;
+		status = devm_acpi_dev_add_driver_gpios(dev, ssam_acpi_gpios);
+		if (status)
+			return status;
+	}
 
 	/* Allocate controller. */
 	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
@@ -655,7 +675,7 @@ static int ssam_serial_hub_probe(struct serdev_device *serdev)
 		goto err_devopen;
 	}
 
-	astatus = ssam_serdev_setup_via_acpi(ssh->handle, serdev);
+	astatus = ssam_serdev_setup(ssh, serdev);
 	if (ACPI_FAILURE(astatus)) {
 		status = dev_err_probe(dev, -ENXIO, "failed to setup serdev\n");
 		goto err_devinit;
@@ -717,10 +737,31 @@ static int ssam_serial_hub_probe(struct serdev_device *serdev)
 	 *       For now let's thus default power/wakeup to false.
 	 */
 	device_set_wakeup_capable(dev, true);
+
+	/*
+	 * When using DT, we have to register the platform hub driver manually,
+	 * as it can't be matched based on top-level board compatible (like it
+	 * does the ACPI case).
+	 */
+	if (!ssh) {
+		struct platform_device *ph_pdev =
+			platform_device_register_simple("surface_aggregator_platform_hub",
+							0, NULL, 0);
+		if (IS_ERR(ph_pdev))
+			return dev_err_probe(dev, PTR_ERR(ph_pdev),
+					     "Failed to register the platform hub driver\n");
+	}
+
+	status = ssam_register_clients(&serdev->dev, ctrl);
+	if (status)
+		goto err_clients;
+
 	acpi_dev_clear_dependencies(ssh);
 
 	return 0;
 
+err_clients:
+	ssam_clear_controller();
 err_mainref:
 	ssam_irq_free(ctrl);
 err_irq:
@@ -782,18 +823,27 @@ static void ssam_serial_hub_remove(struct serdev_device *serdev)
 	device_set_wakeup_capable(&serdev->dev, false);
 }
 
-static const struct acpi_device_id ssam_serial_hub_match[] = {
+static const struct acpi_device_id ssam_serial_hub_acpi_match[] = {
 	{ "MSHW0084", 0 },
 	{ },
 };
-MODULE_DEVICE_TABLE(acpi, ssam_serial_hub_match);
+MODULE_DEVICE_TABLE(acpi, ssam_serial_hub_acpi_match);
+
+#ifdef CONFIG_OF
+static const struct of_device_id ssam_serial_hub_of_match[] = {
+	{ .compatible = "microsoft,surface-sam", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, ssam_serial_hub_of_match);
+#endif
 
 static struct serdev_device_driver ssam_serial_hub = {
 	.probe = ssam_serial_hub_probe,
 	.remove = ssam_serial_hub_remove,
 	.driver = {
 		.name = "surface_serial_hub",
-		.acpi_match_table = ssam_serial_hub_match,
+		.acpi_match_table = ACPI_PTR(ssam_serial_hub_acpi_match),
+		.of_match_table = of_match_ptr(ssam_serial_hub_of_match),
 		.pm = &ssam_serial_hub_pm_ops,
 		.shutdown = ssam_serial_hub_shutdown,
 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 1c4d74db08c9..57787f2ff38b 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -12,6 +12,7 @@
 #include <linux/acpi.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
 #include <linux/types.h>
@@ -273,6 +274,18 @@ static const struct software_node *ssam_node_group_sl5[] = {
 	NULL,
 };
 
+/* Devices for Surface Laptop 7. */
+static const struct software_node *ssam_node_group_sl7[] = {
+	&ssam_node_root,
+	&ssam_node_bat_ac,
+	&ssam_node_bat_main,
+	&ssam_node_tmp_perf_profile_with_fan,
+	&ssam_node_fan_speed,
+	&ssam_node_hid_sam_keyboard,
+	/* TODO: evaluate thermal sensors devices when we get a driver for that */
+	NULL,
+};
+
 /* Devices for Surface Laptop Studio. */
 static const struct software_node *ssam_node_group_sls[] = {
 	&ssam_node_root,
@@ -346,7 +359,7 @@ static const struct software_node *ssam_node_group_sp9[] = {
 
 /* -- SSAM platform/meta-hub driver. ---------------------------------------- */
 
-static const struct acpi_device_id ssam_platform_hub_match[] = {
+static const struct acpi_device_id ssam_platform_hub_acpi_match[] = {
 	/* Surface Pro 4, 5, and 6 (OMBR < 0x10) */
 	{ "MSHW0081", (unsigned long)ssam_node_group_gen5 },
 
@@ -402,16 +415,39 @@ static const struct acpi_device_id ssam_platform_hub_match[] = {
 };
 MODULE_DEVICE_TABLE(acpi, ssam_platform_hub_match);
 
+#ifdef CONFIG_OF
+static const struct of_device_id ssam_platform_hub_of_match[] = {
+	/* Surface Laptop 7 */
+	{ .compatible = "microsoft,romulus13", (void *)ssam_node_group_sl7 },
+	{ .compatible = "microsoft,romulus15", (void *)ssam_node_group_sl7 },
+	{ },
+};
+#endif
+
 static int ssam_platform_hub_probe(struct platform_device *pdev)
 {
 	const struct software_node **nodes;
+	const struct of_device_id *match;
+	struct device_node *fdt_root;
 	struct ssam_controller *ctrl;
 	struct fwnode_handle *root;
 	int status;
 
 	nodes = (const struct software_node **)acpi_device_get_match_data(&pdev->dev);
-	if (!nodes)
-		return -ENODEV;
+	if (!nodes) {
+		fdt_root = of_find_node_by_path("/");
+		if (!fdt_root)
+			return -ENODEV;
+
+		match = of_match_node(ssam_platform_hub_of_match, fdt_root);
+		of_node_put(fdt_root);
+		if (!match)
+			return -ENODEV;
+
+		nodes = (const struct software_node **)match->data;
+		if (!nodes)
+			return -ENODEV;
+	}
 
 	/*
 	 * As we're adding the SSAM client devices as children under this device
@@ -460,7 +496,7 @@ static struct platform_driver ssam_platform_hub_driver = {
 	.remove_new = ssam_platform_hub_remove,
 	.driver = {
 		.name = "surface_aggregator_platform_hub",
-		.acpi_match_table = ssam_platform_hub_match,
+		.acpi_match_table = ssam_platform_hub_acpi_match,
 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
 	},
 };
