// 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 #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", }; /* Base device hub (devices attached to Surface Book 3 base). */ static const struct software_node ssam_node_hub_base = { .name = "ssam:00:00:02:00:00", .parent = &ssam_node_root, }; /* AC adapter. */ static const struct software_node ssam_node_bat_ac = { .name = "ssam:01:02:01:01:01", .parent = &ssam_node_root, }; /* Primary battery. */ static const struct software_node ssam_node_bat_main = { .name = "ssam:01:02:01:01:00", .parent = &ssam_node_root, }; /* Secondary battery (Surface Book 3). */ static const struct software_node ssam_node_bat_sb3base = { .name = "ssam:01:02:02:01:00", .parent = &ssam_node_hub_base, }; /* Platform profile / performance-mode device. */ static const struct software_node ssam_node_tmp_pprof = { .name = "ssam:01:03:01:00:01", .parent = &ssam_node_root, }; /* DTX / detachment-system device (Surface Book 3). */ static const struct software_node ssam_node_bas_dtx = { .name = "ssam:01:11:01:00:00", .parent = &ssam_node_root, }; /* HID keyboard. */ static const struct software_node ssam_node_hid_main_keyboard = { .name = "ssam:01:15:02:01:00", .parent = &ssam_node_root, }; /* HID touchpad. */ static const struct software_node ssam_node_hid_main_touchpad = { .name = "ssam:01:15:02:03:00", .parent = &ssam_node_root, }; /* HID device instance 5 (unknown HID device). */ static const struct software_node ssam_node_hid_main_iid5 = { .name = "ssam:01:15:02:05:00", .parent = &ssam_node_root, }; /* HID keyboard (base hub). */ static const struct software_node ssam_node_hid_base_keyboard = { .name = "ssam:01:15:02:01:00", .parent = &ssam_node_hub_base, }; /* HID touchpad (base hub). */ static const struct software_node ssam_node_hid_base_touchpad = { .name = "ssam:01:15:02:03:00", .parent = &ssam_node_hub_base, }; /* HID device instance 5 (unknown HID device, base hub). */ static const struct software_node ssam_node_hid_base_iid5 = { .name = "ssam:01:15:02:05:00", .parent = &ssam_node_hub_base, }; /* HID device instance 6 (unknown HID device, base hub). */ static const struct software_node ssam_node_hid_base_iid6 = { .name = "ssam:01:15:02:06:00", .parent = &ssam_node_hub_base, }; /* Devices for Surface Book 2. */ static const struct software_node *ssam_node_group_sb2[] = { &ssam_node_root, &ssam_node_tmp_pprof, NULL, }; /* Devices for Surface Book 3. */ static const struct software_node *ssam_node_group_sb3[] = { &ssam_node_root, &ssam_node_hub_base, &ssam_node_bat_ac, &ssam_node_bat_main, &ssam_node_bat_sb3base, &ssam_node_tmp_pprof, &ssam_node_bas_dtx, &ssam_node_hid_base_keyboard, &ssam_node_hid_base_touchpad, &ssam_node_hid_base_iid5, &ssam_node_hid_base_iid6, NULL, }; /* Devices for Surface Laptop 1. */ static const struct software_node *ssam_node_group_sl1[] = { &ssam_node_root, &ssam_node_tmp_pprof, NULL, }; /* Devices for Surface Laptop 2. */ static const struct software_node *ssam_node_group_sl2[] = { &ssam_node_root, &ssam_node_tmp_pprof, NULL, }; /* Devices for Surface Laptop 3. */ static const struct software_node *ssam_node_group_sl3[] = { &ssam_node_root, &ssam_node_bat_ac, &ssam_node_bat_main, &ssam_node_tmp_pprof, &ssam_node_hid_main_keyboard, &ssam_node_hid_main_touchpad, &ssam_node_hid_main_iid5, NULL, }; /* Devices for Surface Laptop Go. */ static const struct software_node *ssam_node_group_slg1[] = { &ssam_node_root, &ssam_node_bat_ac, &ssam_node_bat_main, &ssam_node_tmp_pprof, NULL, }; /* Devices for Surface Pro 5. */ static const struct software_node *ssam_node_group_sp5[] = { &ssam_node_root, &ssam_node_tmp_pprof, NULL, }; /* Devices for Surface Pro 6. */ static const struct software_node *ssam_node_group_sp6[] = { &ssam_node_root, &ssam_node_tmp_pprof, NULL, }; /* Devices for Surface Pro 7 and Surface Pro 7+. */ static const struct software_node *ssam_node_group_sp7[] = { &ssam_node_root, &ssam_node_bat_ac, &ssam_node_bat_main, &ssam_node_tmp_pprof, 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 base-hub driver. ------------------------------------------------- */ enum ssam_base_hub_state { SSAM_BASE_HUB_UNINITIALIZED, SSAM_BASE_HUB_CONNECTED, SSAM_BASE_HUB_DISCONNECTED, }; struct ssam_base_hub { struct ssam_device *sdev; struct mutex lock; /* Guards state update checks and transitions. */ enum ssam_base_hub_state state; struct ssam_event_notifier notif; }; SSAM_DEFINE_SYNC_REQUEST_R(ssam_bas_query_opmode, u8, { .target_category = SSAM_SSH_TC_BAS, .target_id = 0x01, .command_id = 0x0d, .instance_id = 0x00, }); #define SSAM_BAS_OPMODE_TABLET 0x00 #define SSAM_EVENT_BAS_CID_CONNECTION 0x0c static int ssam_base_hub_query_state(struct ssam_base_hub *hub, enum ssam_base_hub_state *state) { u8 opmode; int status; status = ssam_retry(ssam_bas_query_opmode, hub->sdev->ctrl, &opmode); if (status < 0) { dev_err(&hub->sdev->dev, "failed to query base state: %d\n", status); return status; } if (opmode != SSAM_BAS_OPMODE_TABLET) *state = SSAM_BASE_HUB_CONNECTED; else *state = SSAM_BASE_HUB_DISCONNECTED; return 0; } static ssize_t ssam_base_hub_state_show(struct device *dev, struct device_attribute *attr, char *buf) { struct ssam_base_hub *hub = dev_get_drvdata(dev); bool connected; mutex_lock(&hub->lock); connected = hub->state == SSAM_BASE_HUB_CONNECTED; mutex_unlock(&hub->lock); return sysfs_emit(buf, "%d\n", connected); } static struct device_attribute ssam_base_hub_attr_state = __ATTR(state, 0444, ssam_base_hub_state_show, NULL); static struct attribute *ssam_base_hub_attrs[] = { &ssam_base_hub_attr_state.attr, NULL, }; static const struct attribute_group ssam_base_hub_group = { .attrs = ssam_base_hub_attrs, }; static int __ssam_base_hub_update(struct ssam_base_hub *hub, enum ssam_base_hub_state new) { struct fwnode_handle *node = dev_fwnode(&hub->sdev->dev); int status = 0; lockdep_assert_held(&hub->lock); if (hub->state == new) return 0; hub->state = new; if (hub->state == SSAM_BASE_HUB_CONNECTED) status = ssam_hub_add_devices(&hub->sdev->dev, hub->sdev->ctrl, node); else ssam_hub_remove_devices(&hub->sdev->dev); if (status) dev_err(&hub->sdev->dev, "failed to update base-hub devices: %d\n", status); return status; } static int ssam_base_hub_update(struct ssam_base_hub *hub) { enum ssam_base_hub_state state; int status; mutex_lock(&hub->lock); status = ssam_base_hub_query_state(hub, &state); if (!status) status = __ssam_base_hub_update(hub, state); mutex_unlock(&hub->lock); return status; } static u32 ssam_base_hub_notif(struct ssam_event_notifier *nf, const struct ssam_event *event) { struct ssam_base_hub *hub; struct ssam_device *sdev; enum ssam_base_hub_state new; hub = container_of(nf, struct ssam_base_hub, notif); sdev = hub->sdev; if (event->command_id != SSAM_EVENT_BAS_CID_CONNECTION) return 0; if (event->length < 1) { dev_err(&sdev->dev, "unexpected payload size: %u\n", event->length); return 0; } if (event->data[0]) new = SSAM_BASE_HUB_CONNECTED; else new = SSAM_BASE_HUB_DISCONNECTED; mutex_lock(&hub->lock); __ssam_base_hub_update(hub, new); mutex_unlock(&hub->lock); /* * Do not return SSAM_NOTIF_HANDLED: The event should be picked up and * consumed by the detachment system driver. We're just a (more or less) * silent observer. */ return 0; } static int __maybe_unused ssam_base_hub_resume(struct device *dev) { return ssam_base_hub_update(dev_get_drvdata(dev)); } static SIMPLE_DEV_PM_OPS(ssam_base_hub_pm_ops, NULL, ssam_base_hub_resume); static int ssam_base_hub_probe(struct ssam_device *sdev) { struct ssam_base_hub *hub; int status; hub = devm_kzalloc(&sdev->dev, sizeof(*hub), GFP_KERNEL); if (!hub) return -ENOMEM; mutex_init(&hub->lock); hub->sdev = sdev; hub->state = SSAM_BASE_HUB_UNINITIALIZED; hub->notif.base.priority = INT_MAX; /* This notifier should run first. */ hub->notif.base.fn = ssam_base_hub_notif; hub->notif.event.reg = SSAM_EVENT_REGISTRY_SAM; hub->notif.event.id.target_category = SSAM_SSH_TC_BAS, hub->notif.event.id.instance = 0, hub->notif.event.mask = SSAM_EVENT_MASK_NONE; hub->notif.event.flags = SSAM_EVENT_SEQUENCED; ssam_device_set_drvdata(sdev, hub); status = ssam_notifier_register(sdev->ctrl, &hub->notif); if (status) goto err_register; status = ssam_base_hub_update(hub); if (status) goto err_update; status = sysfs_create_group(&sdev->dev.kobj, &ssam_base_hub_group); if (status) goto err_update; return 0; err_update: ssam_notifier_unregister(sdev->ctrl, &hub->notif); ssam_hub_remove_devices(&sdev->dev); err_register: mutex_destroy(&hub->lock); return status; } static void ssam_base_hub_remove(struct ssam_device *sdev) { struct ssam_base_hub *hub = ssam_device_get_drvdata(sdev); sysfs_remove_group(&sdev->dev.kobj, &ssam_base_hub_group); ssam_notifier_unregister(sdev->ctrl, &hub->notif); ssam_hub_remove_devices(&sdev->dev); mutex_destroy(&hub->lock); } static const struct ssam_device_id ssam_base_hub_match[] = { { SSAM_VDEV(HUB, 0x02, SSAM_ANY_IID, 0x00) }, { }, }; static struct ssam_device_driver ssam_base_hub_driver = { .probe = ssam_base_hub_probe, .remove = ssam_base_hub_remove, .match_table = ssam_base_hub_match, .driver = { .name = "surface_aggregator_base_hub", .probe_type = PROBE_PREFER_ASYNCHRONOUS, .pm = &ssam_base_hub_pm_ops, }, }; /* -- 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 Pro 7+ */ { "MSHW0119", (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 initialization. ------------------------------------------------ */ static int __init ssam_device_hub_init(void) { int status; status = platform_driver_register(&ssam_platform_hub_driver); if (status) return status; status = ssam_device_driver_register(&ssam_base_hub_driver); if (status) platform_driver_unregister(&ssam_platform_hub_driver); return status; } module_init(ssam_device_hub_init); static void __exit ssam_device_hub_exit(void) { ssam_device_driver_unregister(&ssam_base_hub_driver); platform_driver_unregister(&ssam_platform_hub_driver); } module_exit(ssam_device_hub_exit); MODULE_AUTHOR("Maximilian Luz "); MODULE_DESCRIPTION("Device-registry for Surface System Aggregator Module"); MODULE_LICENSE("GPL");