/* * Intel Management Engine Interface (Intel MEI) Linux driver * Copyright (c) 2012-2013, Intel Corporation. * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * */ #include #include #include #include #include #include #include #include #include #include #include "mei_dev.h" #include "client.h" #define to_mei_cl_driver(d) container_of(d, struct mei_cl_driver, driver) #define to_mei_cl_device(d) container_of(d, struct mei_cl_device, dev) /** * __mei_cl_send - internal client send (write) * * @cl: host client * @buf: buffer to send * @length: buffer length * @blocking: wait for write completion * * Return: written size bytes or < 0 on error */ ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length, bool blocking) { struct mei_device *bus; struct mei_cl_cb *cb = NULL; ssize_t rets; if (WARN_ON(!cl || !cl->dev)) return -ENODEV; bus = cl->dev; mutex_lock(&bus->device_lock); if (!mei_cl_is_connected(cl)) { rets = -ENODEV; goto out; } /* Check if we have an ME client device */ if (!mei_me_cl_is_active(cl->me_cl)) { rets = -ENOTTY; goto out; } if (length > mei_cl_mtu(cl)) { rets = -EFBIG; goto out; } cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, NULL); if (!cb) { rets = -ENOMEM; goto out; } memcpy(cb->buf.data, buf, length); rets = mei_cl_write(cl, cb, blocking); out: mutex_unlock(&bus->device_lock); if (rets < 0) mei_io_cb_free(cb); return rets; } /** * __mei_cl_recv - internal client receive (read) * * @cl: host client * @buf: buffer to send * @length: buffer length * * Return: read size in bytes of < 0 on error */ ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length) { struct mei_device *bus; struct mei_cl_cb *cb; size_t r_length; ssize_t rets; if (WARN_ON(!cl || !cl->dev)) return -ENODEV; bus = cl->dev; mutex_lock(&bus->device_lock); cb = mei_cl_read_cb(cl, NULL); if (cb) goto copy; rets = mei_cl_read_start(cl, length, NULL); if (rets && rets != -EBUSY) goto out; /* wait on event only if there is no other waiter */ if (list_empty(&cl->rd_completed) && !waitqueue_active(&cl->rx_wait)) { mutex_unlock(&bus->device_lock); if (wait_event_interruptible(cl->rx_wait, (!list_empty(&cl->rd_completed)) || (!mei_cl_is_connected(cl)))) { if (signal_pending(current)) return -EINTR; return -ERESTARTSYS; } mutex_lock(&bus->device_lock); if (!mei_cl_is_connected(cl)) { rets = -EBUSY; goto out; } } cb = mei_cl_read_cb(cl, NULL); if (!cb) { rets = 0; goto out; } copy: if (cb->status) { rets = cb->status; goto free; } r_length = min_t(size_t, length, cb->buf_idx); memcpy(buf, cb->buf.data, r_length); rets = r_length; free: mei_io_cb_free(cb); out: mutex_unlock(&bus->device_lock); return rets; } /** * mei_cl_send - me device send (write) * * @cldev: me client device * @buf: buffer to send * @length: buffer length * * Return: written size in bytes or < 0 on error */ ssize_t mei_cl_send(struct mei_cl_device *cldev, u8 *buf, size_t length) { struct mei_cl *cl = cldev->cl; if (cl == NULL) return -ENODEV; return __mei_cl_send(cl, buf, length, 1); } EXPORT_SYMBOL_GPL(mei_cl_send); /** * mei_cl_recv - client receive (read) * * @cldev: me client device * @buf: buffer to send * @length: buffer length * * Return: read size in bytes of < 0 on error */ ssize_t mei_cl_recv(struct mei_cl_device *cldev, u8 *buf, size_t length) { struct mei_cl *cl = cldev->cl; if (cl == NULL) return -ENODEV; return __mei_cl_recv(cl, buf, length); } EXPORT_SYMBOL_GPL(mei_cl_recv); /** * mei_bus_event_work - dispatch rx event for a bus device * and schedule new work * * @work: work */ static void mei_bus_event_work(struct work_struct *work) { struct mei_cl_device *cldev; cldev = container_of(work, struct mei_cl_device, event_work); if (cldev->event_cb) cldev->event_cb(cldev, cldev->events, cldev->event_context); cldev->events = 0; /* Prepare for the next read */ if (cldev->events_mask & BIT(MEI_CL_EVENT_RX)) mei_cl_read_start(cldev->cl, 0, NULL); } /** * mei_cl_bus_notify_event - schedule notify cb on bus client * * @cl: host client */ void mei_cl_bus_notify_event(struct mei_cl *cl) { struct mei_cl_device *cldev = cl->cldev; if (!cldev || !cldev->event_cb) return; if (!(cldev->events_mask & BIT(MEI_CL_EVENT_NOTIF))) return; if (!cl->notify_ev) return; set_bit(MEI_CL_EVENT_NOTIF, &cldev->events); schedule_work(&cldev->event_work); cl->notify_ev = false; } /** * mei_cl_bus_rx_event - schedule rx evenet * * @cl: host client */ void mei_cl_bus_rx_event(struct mei_cl *cl) { struct mei_cl_device *cldev = cl->cldev; if (!cldev || !cldev->event_cb) return; if (!(cldev->events_mask & BIT(MEI_CL_EVENT_RX))) return; set_bit(MEI_CL_EVENT_RX, &cldev->events); schedule_work(&cldev->event_work); } /** * mei_cl_register_event_cb - register event callback * * @cldev: me client devices * @event_cb: callback function * @events_mask: requested events bitmask * @context: driver context data * * Return: 0 on success * -EALREADY if an callback is already registered * <0 on other errors */ int mei_cl_register_event_cb(struct mei_cl_device *cldev, unsigned long events_mask, mei_cl_event_cb_t event_cb, void *context) { int ret; if (cldev->event_cb) return -EALREADY; cldev->events = 0; cldev->events_mask = events_mask; cldev->event_cb = event_cb; cldev->event_context = context; INIT_WORK(&cldev->event_work, mei_bus_event_work); if (cldev->events_mask & BIT(MEI_CL_EVENT_RX)) { ret = mei_cl_read_start(cldev->cl, 0, NULL); if (ret && ret != -EBUSY) return ret; } if (cldev->events_mask & BIT(MEI_CL_EVENT_NOTIF)) { mutex_lock(&cldev->cl->dev->device_lock); ret = mei_cl_notify_request(cldev->cl, NULL, event_cb ? 1 : 0); mutex_unlock(&cldev->cl->dev->device_lock); if (ret) return ret; } return 0; } EXPORT_SYMBOL_GPL(mei_cl_register_event_cb); /** * mei_cl_get_drvdata - driver data getter * * @cldev: mei client device * * Return: driver private data */ void *mei_cl_get_drvdata(const struct mei_cl_device *cldev) { return dev_get_drvdata(&cldev->dev); } EXPORT_SYMBOL_GPL(mei_cl_get_drvdata); /** * mei_cl_set_drvdata - driver data setter * * @cldev: mei client device * @data: data to store */ void mei_cl_set_drvdata(struct mei_cl_device *cldev, void *data) { dev_set_drvdata(&cldev->dev, data); } EXPORT_SYMBOL_GPL(mei_cl_set_drvdata); /** * mei_cl_enable_device - enable me client device * create connection with me client * * @cldev: me client device * * Return: 0 on success and < 0 on error */ int mei_cl_enable_device(struct mei_cl_device *cldev) { struct mei_device *bus = cldev->bus; struct mei_cl *cl; int ret; cl = cldev->cl; if (!cl) { mutex_lock(&bus->device_lock); cl = mei_cl_alloc_linked(bus, MEI_HOST_CLIENT_ID_ANY); mutex_unlock(&bus->device_lock); if (IS_ERR(cl)) return PTR_ERR(cl); /* update pointers */ cldev->cl = cl; cl->cldev = cldev; } mutex_lock(&bus->device_lock); if (mei_cl_is_connected(cl)) { ret = 0; goto out; } if (!mei_me_cl_is_active(cldev->me_cl)) { dev_err(&cldev->dev, "me client is not active\n"); ret = -ENOTTY; goto out; } ret = mei_cl_connect(cl, cldev->me_cl, NULL); if (ret < 0) dev_err(&cldev->dev, "cannot connect\n"); out: mutex_unlock(&bus->device_lock); return ret; } EXPORT_SYMBOL_GPL(mei_cl_enable_device); /** * mei_cl_disable_device - disable me client device * disconnect form the me client * * @cldev: me client device * * Return: 0 on success and < 0 on error */ int mei_cl_disable_device(struct mei_cl_device *cldev) { struct mei_device *bus; struct mei_cl *cl; int err; if (!cldev || !cldev->cl) return -ENODEV; cl = cldev->cl; bus = cldev->bus; cldev->event_cb = NULL; mutex_lock(&bus->device_lock); if (!mei_cl_is_connected(cl)) { dev_err(bus->dev, "Already disconnected"); err = 0; goto out; } err = mei_cl_disconnect(cl); if (err < 0) dev_err(bus->dev, "Could not disconnect from the ME client"); out: /* Flush queues and remove any pending read */ mei_cl_flush_queues(cl, NULL); mei_cl_unlink(cl); kfree(cl); cldev->cl = NULL; mutex_unlock(&bus->device_lock); return err; } EXPORT_SYMBOL_GPL(mei_cl_disable_device); /** * mei_cl_device_find - find matching entry in the driver id table * * @cldev: me client device * @cldrv: me client driver * * Return: id on success; NULL if no id is matching */ static const struct mei_cl_device_id *mei_cl_device_find(struct mei_cl_device *cldev, struct mei_cl_driver *cldrv) { const struct mei_cl_device_id *id; const uuid_le *uuid; u8 version; bool match; uuid = mei_me_cl_uuid(cldev->me_cl); version = mei_me_cl_ver(cldev->me_cl); id = cldrv->id_table; while (uuid_le_cmp(NULL_UUID_LE, id->uuid)) { if (!uuid_le_cmp(*uuid, id->uuid)) { match = true; if (cldev->name[0]) if (strncmp(cldev->name, id->name, sizeof(id->name))) match = false; if (id->version != MEI_CL_VERSION_ANY) if (id->version != version) match = false; if (match) return id; } id++; } return NULL; } /** * mei_cl_device_match - device match function * * @dev: device * @drv: driver * * Return: 1 if matching device was found 0 otherwise */ static int mei_cl_device_match(struct device *dev, struct device_driver *drv) { struct mei_cl_device *cldev = to_mei_cl_device(dev); struct mei_cl_driver *cldrv = to_mei_cl_driver(drv); const struct mei_cl_device_id *found_id; if (!cldev) return 0; if (!cldev->do_match) return 0; if (!cldrv || !cldrv->id_table) return 0; found_id = mei_cl_device_find(cldev, cldrv); if (found_id) return 1; return 0; } /** * mei_cl_device_probe - bus probe function * * @dev: device * * Return: 0 on success; < 0 otherwise */ static int mei_cl_device_probe(struct device *dev) { struct mei_cl_device *cldev; struct mei_cl_driver *cldrv; const struct mei_cl_device_id *id; cldev = to_mei_cl_device(dev); cldrv = to_mei_cl_driver(dev->driver); if (!cldev) return 0; if (!cldrv || !cldrv->probe) return -ENODEV; id = mei_cl_device_find(cldev, cldrv); if (!id) return -ENODEV; __module_get(THIS_MODULE); return cldrv->probe(cldev, id); } /** * mei_cl_device_remove - remove device from the bus * * @dev: device * * Return: 0 on success; < 0 otherwise */ static int mei_cl_device_remove(struct device *dev) { struct mei_cl_device *cldev = to_mei_cl_device(dev); struct mei_cl_driver *cldrv; int ret = 0; if (!cldev || !dev->driver) return 0; if (cldev->event_cb) { cldev->event_cb = NULL; cancel_work_sync(&cldev->event_work); } cldrv = to_mei_cl_driver(dev->driver); if (cldrv->remove) ret = cldrv->remove(cldev); module_put(THIS_MODULE); dev->driver = NULL; return ret; } static ssize_t name_show(struct device *dev, struct device_attribute *a, char *buf) { struct mei_cl_device *cldev = to_mei_cl_device(dev); size_t len; len = snprintf(buf, PAGE_SIZE, "%s", cldev->name); return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len; } static DEVICE_ATTR_RO(name); static ssize_t uuid_show(struct device *dev, struct device_attribute *a, char *buf) { struct mei_cl_device *cldev = to_mei_cl_device(dev); const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl); size_t len; len = snprintf(buf, PAGE_SIZE, "%pUl", uuid); return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len; } static DEVICE_ATTR_RO(uuid); static ssize_t version_show(struct device *dev, struct device_attribute *a, char *buf) { struct mei_cl_device *cldev = to_mei_cl_device(dev); u8 version = mei_me_cl_ver(cldev->me_cl); size_t len; len = snprintf(buf, PAGE_SIZE, "%02X", version); return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len; } static DEVICE_ATTR_RO(version); static ssize_t modalias_show(struct device *dev, struct device_attribute *a, char *buf) { struct mei_cl_device *cldev = to_mei_cl_device(dev); const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl); size_t len; len = snprintf(buf, PAGE_SIZE, "mei:%s:%pUl:", cldev->name, uuid); return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len; } static DEVICE_ATTR_RO(modalias); static struct attribute *mei_cl_dev_attrs[] = { &dev_attr_name.attr, &dev_attr_uuid.attr, &dev_attr_version.attr, &dev_attr_modalias.attr, NULL, }; ATTRIBUTE_GROUPS(mei_cl_dev); /** * mei_cl_device_uevent - me client bus uevent handler * * @dev: device * @env: uevent kobject * * Return: 0 on success -ENOMEM on when add_uevent_var fails */ static int mei_cl_device_uevent(struct device *dev, struct kobj_uevent_env *env) { struct mei_cl_device *cldev = to_mei_cl_device(dev); const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl); u8 version = mei_me_cl_ver(cldev->me_cl); if (add_uevent_var(env, "MEI_CL_VERSION=%d", version)) return -ENOMEM; if (add_uevent_var(env, "MEI_CL_UUID=%pUl", uuid)) return -ENOMEM; if (add_uevent_var(env, "MEI_CL_NAME=%s", cldev->name)) return -ENOMEM; if (add_uevent_var(env, "MODALIAS=mei:%s:%pUl:%02X:", cldev->name, uuid, version)) return -ENOMEM; return 0; } static struct bus_type mei_cl_bus_type = { .name = "mei", .dev_groups = mei_cl_dev_groups, .match = mei_cl_device_match, .probe = mei_cl_device_probe, .remove = mei_cl_device_remove, .uevent = mei_cl_device_uevent, }; static struct mei_device *mei_dev_bus_get(struct mei_device *bus) { if (bus) get_device(bus->dev); return bus; } static void mei_dev_bus_put(struct mei_device *bus) { if (bus) put_device(bus->dev); } static void mei_cl_dev_release(struct device *dev) { struct mei_cl_device *cldev = to_mei_cl_device(dev); if (!cldev) return; mei_me_cl_put(cldev->me_cl); mei_dev_bus_put(cldev->bus); kfree(cldev); } static struct device_type mei_cl_device_type = { .release = mei_cl_dev_release, }; /** * mei_cl_dev_alloc - initialize and allocate mei client device * * @bus: mei device * @me_cl: me client * * Return: allocated device structur or NULL on allocation failure */ static struct mei_cl_device *mei_cl_dev_alloc(struct mei_device *bus, struct mei_me_client *me_cl) { struct mei_cl_device *cldev; cldev = kzalloc(sizeof(struct mei_cl_device), GFP_KERNEL); if (!cldev) return NULL; device_initialize(&cldev->dev); cldev->dev.parent = bus->dev; cldev->dev.bus = &mei_cl_bus_type; cldev->dev.type = &mei_cl_device_type; cldev->bus = mei_dev_bus_get(bus); cldev->me_cl = mei_me_cl_get(me_cl); cldev->is_added = 0; INIT_LIST_HEAD(&cldev->bus_list); return cldev; } /** * mei_cl_dev_setup - setup me client device * run fix up routines and set the device name * * @bus: mei device * @cldev: me client device * * Return: true if the device is eligible for enumeration */ static bool mei_cl_dev_setup(struct mei_device *bus, struct mei_cl_device *cldev) { cldev->do_match = 1; mei_cl_dev_fixup(cldev); if (cldev->do_match) dev_set_name(&cldev->dev, "mei:%s:%pUl:%02X", cldev->name, mei_me_cl_uuid(cldev->me_cl), mei_me_cl_ver(cldev->me_cl)); return cldev->do_match == 1; } /** * mei_cl_bus_dev_add - add me client devices * * @cldev: me client device * * Return: 0 on success; < 0 on failre */ static int mei_cl_bus_dev_add(struct mei_cl_device *cldev) { int ret; dev_dbg(cldev->bus->dev, "adding %pUL:%02X\n", mei_me_cl_uuid(cldev->me_cl), mei_me_cl_ver(cldev->me_cl)); ret = device_add(&cldev->dev); if (!ret) cldev->is_added = 1; return ret; } /** * mei_cl_bus_dev_stop - stop the driver * * @cldev: me client device */ static void mei_cl_bus_dev_stop(struct mei_cl_device *cldev) { if (cldev->is_added) device_release_driver(&cldev->dev); } /** * mei_cl_bus_dev_destroy - destroy me client devices object * * @cldev: me client device */ static void mei_cl_bus_dev_destroy(struct mei_cl_device *cldev) { if (!cldev->is_added) return; device_del(&cldev->dev); mutex_lock(&cldev->bus->cl_bus_lock); list_del_init(&cldev->bus_list); mutex_unlock(&cldev->bus->cl_bus_lock); cldev->is_added = 0; put_device(&cldev->dev); } /** * mei_cl_bus_remove_device - remove a devices form the bus * * @cldev: me client device */ static void mei_cl_bus_remove_device(struct mei_cl_device *cldev) { mei_cl_bus_dev_stop(cldev); mei_cl_bus_dev_destroy(cldev); } /** * mei_cl_bus_remove_devices - remove all devices form the bus * * @bus: mei device */ void mei_cl_bus_remove_devices(struct mei_device *bus) { struct mei_cl_device *cldev, *next; list_for_each_entry_safe(cldev, next, &bus->device_list, bus_list) mei_cl_bus_remove_device(cldev); } /** * mei_cl_dev_init - allocate and initializes an mei client devices * based on me client * * @bus: mei device * @me_cl: me client */ static void mei_cl_dev_init(struct mei_device *bus, struct mei_me_client *me_cl) { struct mei_cl_device *cldev; dev_dbg(bus->dev, "initializing %pUl", mei_me_cl_uuid(me_cl)); if (me_cl->bus_added) return; cldev = mei_cl_dev_alloc(bus, me_cl); if (!cldev) return; mutex_lock(&cldev->bus->cl_bus_lock); me_cl->bus_added = true; list_add_tail(&cldev->bus_list, &bus->device_list); mutex_unlock(&cldev->bus->cl_bus_lock); } /** * mei_cl_bus_rescan - scan me clients list and add create * devices for eligible clients * * @bus: mei device */ void mei_cl_bus_rescan(struct mei_device *bus) { struct mei_cl_device *cldev, *n; struct mei_me_client *me_cl; down_read(&bus->me_clients_rwsem); list_for_each_entry(me_cl, &bus->me_clients, list) mei_cl_dev_init(bus, me_cl); up_read(&bus->me_clients_rwsem); mutex_lock(&bus->cl_bus_lock); list_for_each_entry_safe(cldev, n, &bus->device_list, bus_list) { if (!mei_me_cl_is_active(cldev->me_cl)) { mei_cl_bus_remove_device(cldev); continue; } if (cldev->is_added) continue; if (mei_cl_dev_setup(bus, cldev)) mei_cl_bus_dev_add(cldev); else { list_del_init(&cldev->bus_list); put_device(&cldev->dev); } } mutex_unlock(&bus->cl_bus_lock); dev_dbg(bus->dev, "rescan end"); } int __mei_cl_driver_register(struct mei_cl_driver *cldrv, struct module *owner) { int err; cldrv->driver.name = cldrv->name; cldrv->driver.owner = owner; cldrv->driver.bus = &mei_cl_bus_type; err = driver_register(&cldrv->driver); if (err) return err; pr_debug("mei: driver [%s] registered\n", cldrv->driver.name); return 0; } EXPORT_SYMBOL_GPL(__mei_cl_driver_register); void mei_cl_driver_unregister(struct mei_cl_driver *cldrv) { driver_unregister(&cldrv->driver); pr_debug("mei: driver [%s] unregistered\n", cldrv->driver.name); } EXPORT_SYMBOL_GPL(mei_cl_driver_unregister); int __init mei_cl_bus_init(void) { return bus_register(&mei_cl_bus_type); } void __exit mei_cl_bus_exit(void) { bus_unregister(&mei_cl_bus_type); }