diff options
Diffstat (limited to 'drivers/misc/mei/bus.c')
-rw-r--r-- | drivers/misc/mei/bus.c | 528 |
1 files changed, 528 insertions, 0 deletions
diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c new file mode 100644 index 00000000000..1e935eacaa7 --- /dev/null +++ b/drivers/misc/mei/bus.c @@ -0,0 +1,528 @@ +/* + * 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 <linux/module.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/mutex.h> +#include <linux/interrupt.h> +#include <linux/pci.h> +#include <linux/mei_cl_bus.h> + +#include "mei_dev.h" +#include "hw-me.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) + +static int mei_cl_device_match(struct device *dev, struct device_driver *drv) +{ + struct mei_cl_device *device = to_mei_cl_device(dev); + struct mei_cl_driver *driver = to_mei_cl_driver(drv); + const struct mei_cl_device_id *id; + + if (!device) + return 0; + + if (!driver || !driver->id_table) + return 0; + + id = driver->id_table; + + while (id->name[0]) { + if (!strcmp(dev_name(dev), id->name)) + return 1; + + id++; + } + + return 0; +} + +static int mei_cl_device_probe(struct device *dev) +{ + struct mei_cl_device *device = to_mei_cl_device(dev); + struct mei_cl_driver *driver; + struct mei_cl_device_id id; + + if (!device) + return 0; + + driver = to_mei_cl_driver(dev->driver); + if (!driver || !driver->probe) + return -ENODEV; + + dev_dbg(dev, "Device probe\n"); + + strncpy(id.name, dev_name(dev), MEI_CL_NAME_SIZE); + + return driver->probe(device, &id); +} + +static int mei_cl_device_remove(struct device *dev) +{ + struct mei_cl_device *device = to_mei_cl_device(dev); + struct mei_cl_driver *driver; + + if (!device || !dev->driver) + return 0; + + if (device->event_cb) { + device->event_cb = NULL; + cancel_work_sync(&device->event_work); + } + + driver = to_mei_cl_driver(dev->driver); + if (!driver->remove) { + dev->driver = NULL; + + return 0; + } + + return driver->remove(device); +} + +static ssize_t modalias_show(struct device *dev, struct device_attribute *a, + char *buf) +{ + int len; + + len = snprintf(buf, PAGE_SIZE, "mei:%s\n", dev_name(dev)); + + return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len; +} + +static struct device_attribute mei_cl_dev_attrs[] = { + __ATTR_RO(modalias), + __ATTR_NULL, +}; + +static int mei_cl_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + if (add_uevent_var(env, "MODALIAS=mei:%s", dev_name(dev))) + return -ENOMEM; + + return 0; +} + +static struct bus_type mei_cl_bus_type = { + .name = "mei", + .dev_attrs = mei_cl_dev_attrs, + .match = mei_cl_device_match, + .probe = mei_cl_device_probe, + .remove = mei_cl_device_remove, + .uevent = mei_cl_uevent, +}; + +static void mei_cl_dev_release(struct device *dev) +{ + kfree(to_mei_cl_device(dev)); +} + +static struct device_type mei_cl_device_type = { + .release = mei_cl_dev_release, +}; + +static struct mei_cl *mei_bus_find_mei_cl_by_uuid(struct mei_device *dev, + uuid_le uuid) +{ + struct mei_cl *cl, *next; + + list_for_each_entry_safe(cl, next, &dev->device_list, device_link) { + if (!uuid_le_cmp(uuid, cl->device_uuid)) + return cl; + } + + return NULL; +} +struct mei_cl_device *mei_cl_add_device(struct mei_device *dev, + uuid_le uuid, char *name, + struct mei_cl_ops *ops) +{ + struct mei_cl_device *device; + struct mei_cl *cl; + int status; + + cl = mei_bus_find_mei_cl_by_uuid(dev, uuid); + if (cl == NULL) + return NULL; + + device = kzalloc(sizeof(struct mei_cl_device), GFP_KERNEL); + if (!device) + return NULL; + + device->cl = cl; + device->ops = ops; + + device->dev.parent = &dev->pdev->dev; + device->dev.bus = &mei_cl_bus_type; + device->dev.type = &mei_cl_device_type; + + dev_set_name(&device->dev, "%s", name); + + status = device_register(&device->dev); + if (status) { + dev_err(&dev->pdev->dev, "Failed to register MEI device\n"); + kfree(device); + return NULL; + } + + cl->device = device; + + dev_dbg(&device->dev, "client %s registered\n", name); + + return device; +} +EXPORT_SYMBOL_GPL(mei_cl_add_device); + +void mei_cl_remove_device(struct mei_cl_device *device) +{ + device_unregister(&device->dev); +} +EXPORT_SYMBOL_GPL(mei_cl_remove_device); + +int __mei_cl_driver_register(struct mei_cl_driver *driver, struct module *owner) +{ + int err; + + driver->driver.name = driver->name; + driver->driver.owner = owner; + driver->driver.bus = &mei_cl_bus_type; + + err = driver_register(&driver->driver); + if (err) + return err; + + pr_debug("mei: driver [%s] registered\n", driver->driver.name); + + return 0; +} +EXPORT_SYMBOL_GPL(__mei_cl_driver_register); + +void mei_cl_driver_unregister(struct mei_cl_driver *driver) +{ + driver_unregister(&driver->driver); + + pr_debug("mei: driver [%s] unregistered\n", driver->driver.name); +} +EXPORT_SYMBOL_GPL(mei_cl_driver_unregister); + +static int ___mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length, + bool blocking) +{ + struct mei_device *dev; + struct mei_cl_cb *cb; + int id; + int rets; + + if (WARN_ON(!cl || !cl->dev)) + return -ENODEV; + + dev = cl->dev; + + if (cl->state != MEI_FILE_CONNECTED) + return -ENODEV; + + /* Check if we have an ME client device */ + id = mei_me_cl_by_id(dev, cl->me_client_id); + if (id < 0) + return -ENODEV; + + if (length > dev->me_clients[id].props.max_msg_length) + return -EINVAL; + + cb = mei_io_cb_init(cl, NULL); + if (!cb) + return -ENOMEM; + + rets = mei_io_cb_alloc_req_buf(cb, length); + if (rets < 0) { + mei_io_cb_free(cb); + return rets; + } + + memcpy(cb->request_buffer.data, buf, length); + + mutex_lock(&dev->device_lock); + + rets = mei_cl_write(cl, cb, blocking); + + mutex_unlock(&dev->device_lock); + if (rets < 0) + mei_io_cb_free(cb); + + return rets; +} + +int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length) +{ + struct mei_device *dev; + struct mei_cl_cb *cb; + size_t r_length; + int err; + + if (WARN_ON(!cl || !cl->dev)) + return -ENODEV; + + dev = cl->dev; + + mutex_lock(&dev->device_lock); + + if (!cl->read_cb) { + err = mei_cl_read_start(cl, length); + if (err < 0) { + mutex_unlock(&dev->device_lock); + return err; + } + } + + if (cl->reading_state != MEI_READ_COMPLETE && + !waitqueue_active(&cl->rx_wait)) { + mutex_unlock(&dev->device_lock); + + if (wait_event_interruptible(cl->rx_wait, + (MEI_READ_COMPLETE == cl->reading_state))) { + if (signal_pending(current)) + return -EINTR; + return -ERESTARTSYS; + } + + mutex_lock(&dev->device_lock); + } + + cb = cl->read_cb; + + if (cl->reading_state != MEI_READ_COMPLETE) { + r_length = 0; + goto out; + } + + r_length = min_t(size_t, length, cb->buf_idx); + + memcpy(buf, cb->response_buffer.data, r_length); + + mei_io_cb_free(cb); + cl->reading_state = MEI_IDLE; + cl->read_cb = NULL; + +out: + mutex_unlock(&dev->device_lock); + + return r_length; +} + +inline int __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length) +{ + return ___mei_cl_send(cl, buf, length, 0); +} + +inline int __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length) +{ + return ___mei_cl_send(cl, buf, length, 1); +} + +int mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length) +{ + struct mei_cl *cl = device->cl; + + if (cl == NULL) + return -ENODEV; + + if (device->ops && device->ops->send) + return device->ops->send(device, buf, length); + + return __mei_cl_send(cl, buf, length); +} +EXPORT_SYMBOL_GPL(mei_cl_send); + +int mei_cl_recv(struct mei_cl_device *device, u8 *buf, size_t length) +{ + struct mei_cl *cl = device->cl; + + if (cl == NULL) + return -ENODEV; + + if (device->ops && device->ops->recv) + return device->ops->recv(device, buf, length); + + return __mei_cl_recv(cl, buf, length); +} +EXPORT_SYMBOL_GPL(mei_cl_recv); + +static void mei_bus_event_work(struct work_struct *work) +{ + struct mei_cl_device *device; + + device = container_of(work, struct mei_cl_device, event_work); + + if (device->event_cb) + device->event_cb(device, device->events, device->event_context); + + device->events = 0; + + /* Prepare for the next read */ + mei_cl_read_start(device->cl, 0); +} + +int mei_cl_register_event_cb(struct mei_cl_device *device, + mei_cl_event_cb_t event_cb, void *context) +{ + if (device->event_cb) + return -EALREADY; + + device->events = 0; + device->event_cb = event_cb; + device->event_context = context; + INIT_WORK(&device->event_work, mei_bus_event_work); + + mei_cl_read_start(device->cl, 0); + + return 0; +} +EXPORT_SYMBOL_GPL(mei_cl_register_event_cb); + +void *mei_cl_get_drvdata(const struct mei_cl_device *device) +{ + return dev_get_drvdata(&device->dev); +} +EXPORT_SYMBOL_GPL(mei_cl_get_drvdata); + +void mei_cl_set_drvdata(struct mei_cl_device *device, void *data) +{ + dev_set_drvdata(&device->dev, data); +} +EXPORT_SYMBOL_GPL(mei_cl_set_drvdata); + +int mei_cl_enable_device(struct mei_cl_device *device) +{ + int err; + struct mei_device *dev; + struct mei_cl *cl = device->cl; + + if (cl == NULL) + return -ENODEV; + + dev = cl->dev; + + mutex_lock(&dev->device_lock); + + cl->state = MEI_FILE_CONNECTING; + + err = mei_cl_connect(cl, NULL); + if (err < 0) { + mutex_unlock(&dev->device_lock); + dev_err(&dev->pdev->dev, "Could not connect to the ME client"); + + return err; + } + + mutex_unlock(&dev->device_lock); + + if (device->event_cb && !cl->read_cb) + mei_cl_read_start(device->cl, 0); + + if (!device->ops || !device->ops->enable) + return 0; + + return device->ops->enable(device); +} +EXPORT_SYMBOL_GPL(mei_cl_enable_device); + +int mei_cl_disable_device(struct mei_cl_device *device) +{ + int err; + struct mei_device *dev; + struct mei_cl *cl = device->cl; + + if (cl == NULL) + return -ENODEV; + + dev = cl->dev; + + mutex_lock(&dev->device_lock); + + if (cl->state != MEI_FILE_CONNECTED) { + mutex_unlock(&dev->device_lock); + dev_err(&dev->pdev->dev, "Already disconnected"); + + return 0; + } + + cl->state = MEI_FILE_DISCONNECTING; + + err = mei_cl_disconnect(cl); + if (err < 0) { + mutex_unlock(&dev->device_lock); + dev_err(&dev->pdev->dev, + "Could not disconnect from the ME client"); + + return err; + } + + /* Flush queues and remove any pending read */ + mei_cl_flush_queues(cl); + + if (cl->read_cb) { + struct mei_cl_cb *cb = NULL; + + cb = mei_cl_find_read_cb(cl); + /* Remove entry from read list */ + if (cb) + list_del(&cb->list); + + cb = cl->read_cb; + cl->read_cb = NULL; + + if (cb) { + mei_io_cb_free(cb); + cb = NULL; + } + } + + mutex_unlock(&dev->device_lock); + + if (!device->ops || !device->ops->disable) + return 0; + + return device->ops->disable(device); +} +EXPORT_SYMBOL_GPL(mei_cl_disable_device); + +void mei_cl_bus_rx_event(struct mei_cl *cl) +{ + struct mei_cl_device *device = cl->device; + + if (!device || !device->event_cb) + return; + + set_bit(MEI_CL_EVENT_RX, &device->events); + + schedule_work(&device->event_work); +} + +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); +} |