// SPDX-License-Identifier: GPL-2.0+ /* * Surface System Aggregator Module (SSAM) client device registry. * * Registry for non-platform/non-ACPI SSAM client devices, i.e. devices that * cannot be auto-detected. Provides device-hubs and performs instantiation * for these devices. * * Copyright (C) 2020-2021 Maximilian Luz */ #include #include #include #include #include #include #include /* -- Device registry. ------------------------------------------------------ */ /* * SSAM device names follow the SSAM module alias, meaning they are prefixed * with 'ssam:', followed by domain, category, target ID, instance ID, and * function, each encoded as two-digit hexadecimal, separated by ':'. In other * words, it follows the scheme * * ssam:dd:cc:tt:ii:ff * * Where, 'dd', 'cc', 'tt', 'ii', and 'ff' are the two-digit hexadecimal * values mentioned above, respectively. */ /* Root node. */ static const struct software_node ssam_node_root = { .name = "ssam_platform_hub", }; /* Devices for Surface Book 2. */ static const struct software_node *ssam_node_group_sb2[] = { &ssam_node_root, NULL, }; /* Devices for Surface Book 3. */ static const struct software_node *ssam_node_group_sb3[] = { &ssam_node_root, NULL, }; /* Devices for Surface Laptop 1. */ static const struct software_node *ssam_node_group_sl1[] = { &ssam_node_root, NULL, }; /* Devices for Surface Laptop 2. */ static const struct software_node *ssam_node_group_sl2[] = { &ssam_node_root, NULL, }; /* Devices for Surface Laptop 3. */ static const struct software_node *ssam_node_group_sl3[] = { &ssam_node_root, NULL, }; /* Devices for Surface Laptop Go. */ static const struct software_node *ssam_node_group_slg1[] = { &ssam_node_root, NULL, }; /* Devices for Surface Pro 5. */ static const struct software_node *ssam_node_group_sp5[] = { &ssam_node_root, NULL, }; /* Devices for Surface Pro 6. */ static const struct software_node *ssam_node_group_sp6[] = { &ssam_node_root, NULL, }; /* Devices for Surface Pro 7. */ static const struct software_node *ssam_node_group_sp7[] = { &ssam_node_root, NULL, }; /* -- Device registry helper functions. ------------------------------------- */ static int ssam_uid_from_string(const char *str, struct ssam_device_uid *uid) { u8 d, tc, tid, iid, fn; int n; n = sscanf(str, "ssam:%hhx:%hhx:%hhx:%hhx:%hhx", &d, &tc, &tid, &iid, &fn); if (n != 5) return -EINVAL; uid->domain = d; uid->category = tc; uid->target = tid; uid->instance = iid; uid->function = fn; return 0; } static int ssam_hub_remove_devices_fn(struct device *dev, void *data) { if (!is_ssam_device(dev)) return 0; ssam_device_remove(to_ssam_device(dev)); return 0; } static void ssam_hub_remove_devices(struct device *parent) { device_for_each_child_reverse(parent, NULL, ssam_hub_remove_devices_fn); } static int ssam_hub_add_device(struct device *parent, struct ssam_controller *ctrl, struct fwnode_handle *node) { struct ssam_device_uid uid; struct ssam_device *sdev; int status; status = ssam_uid_from_string(fwnode_get_name(node), &uid); if (status) return status; sdev = ssam_device_alloc(ctrl, uid); if (!sdev) return -ENOMEM; sdev->dev.parent = parent; sdev->dev.fwnode = node; status = ssam_device_add(sdev); if (status) ssam_device_put(sdev); return status; } static int ssam_hub_add_devices(struct device *parent, struct ssam_controller *ctrl, struct fwnode_handle *node) { struct fwnode_handle *child; int status; fwnode_for_each_child_node(node, child) { /* * Try to add the device specified in the firmware node. If * this fails with -EINVAL, the node does not specify any SSAM * device, so ignore it and continue with the next one. */ status = ssam_hub_add_device(parent, ctrl, child); if (status && status != -EINVAL) goto err; } return 0; err: ssam_hub_remove_devices(parent); return status; } /* -- SSAM platform/meta-hub driver. ---------------------------------------- */ static const struct acpi_device_id ssam_platform_hub_match[] = { /* Surface Pro 4, 5, and 6 (OMBR < 0x10) */ { "MSHW0081", (unsigned long)ssam_node_group_sp5 }, /* Surface Pro 6 (OMBR >= 0x10) */ { "MSHW0111", (unsigned long)ssam_node_group_sp6 }, /* Surface Pro 7 */ { "MSHW0116", (unsigned long)ssam_node_group_sp7 }, /* Surface Book 2 */ { "MSHW0107", (unsigned long)ssam_node_group_sb2 }, /* Surface Book 3 */ { "MSHW0117", (unsigned long)ssam_node_group_sb3 }, /* Surface Laptop 1 */ { "MSHW0086", (unsigned long)ssam_node_group_sl1 }, /* Surface Laptop 2 */ { "MSHW0112", (unsigned long)ssam_node_group_sl2 }, /* Surface Laptop 3 (13", Intel) */ { "MSHW0114", (unsigned long)ssam_node_group_sl3 }, /* Surface Laptop 3 (15", AMD) */ { "MSHW0110", (unsigned long)ssam_node_group_sl3 }, /* Surface Laptop Go 1 */ { "MSHW0118", (unsigned long)ssam_node_group_slg1 }, { }, }; MODULE_DEVICE_TABLE(acpi, ssam_platform_hub_match); static int ssam_platform_hub_probe(struct platform_device *pdev) { const struct software_node **nodes; 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; /* * As we're adding the SSAM client devices as children under this device * and not the SSAM controller, we need to add a device link to the * controller to ensure that we remove all of our devices before the * controller is removed. This also guarantees proper ordering for * suspend/resume of the devices on this hub. */ ctrl = ssam_client_bind(&pdev->dev); if (IS_ERR(ctrl)) return PTR_ERR(ctrl) == -ENODEV ? -EPROBE_DEFER : PTR_ERR(ctrl); status = software_node_register_node_group(nodes); if (status) return status; root = software_node_fwnode(&ssam_node_root); if (!root) { software_node_unregister_node_group(nodes); return -ENOENT; } set_secondary_fwnode(&pdev->dev, root); status = ssam_hub_add_devices(&pdev->dev, ctrl, root); if (status) { set_secondary_fwnode(&pdev->dev, NULL); software_node_unregister_node_group(nodes); } platform_set_drvdata(pdev, nodes); return status; } static int ssam_platform_hub_remove(struct platform_device *pdev) { const struct software_node **nodes = platform_get_drvdata(pdev); ssam_hub_remove_devices(&pdev->dev); set_secondary_fwnode(&pdev->dev, NULL); software_node_unregister_node_group(nodes); return 0; } static struct platform_driver ssam_platform_hub_driver = { .probe = ssam_platform_hub_probe, .remove = ssam_platform_hub_remove, .driver = { .name = "surface_aggregator_platform_hub", .acpi_match_table = ssam_platform_hub_match, .probe_type = PROBE_PREFER_ASYNCHRONOUS, }, }; module_platform_driver(ssam_platform_hub_driver); MODULE_AUTHOR("Maximilian Luz "); MODULE_DESCRIPTION("Device-registry for Surface System Aggregator Module"); MODULE_LICENSE("GPL");