Project import generated by Copybara.

NOKEYCHECK=True
GitOrigin-RevId: c16c7d2197632d3af4aabb80761c81918c830e0f
diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c
new file mode 100644
index 0000000..4cf38c3
--- /dev/null
+++ b/drivers/misc/mei/bus.c
@@ -0,0 +1,537 @@
+/*
+ * 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/mei_cl_bus.h>
+
+#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)
+
+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 (!strncmp(dev_name(dev), id->name, sizeof(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");
+
+	strlcpy(id.name, dev_name(dev), sizeof(id.name));
+
+	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 DEVICE_ATTR_RO(modalias);
+
+static struct attribute *mei_cl_dev_attrs[] = {
+	&dev_attr_modalias.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(mei_cl_dev);
+
+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_groups	= mei_cl_dev_groups,
+	.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,
+};
+
+struct mei_cl *mei_cl_bus_find_cl_by_uuid(struct mei_device *dev,
+						uuid_le uuid)
+{
+	struct mei_cl *cl;
+
+	list_for_each_entry(cl, &dev->device_list, device_link) {
+		if (!uuid_le_cmp(uuid, cl->cl_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_cl_bus_find_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->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->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 ssize_t ___mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
+			bool blocking)
+{
+	struct mei_device *dev;
+	struct mei_me_client *me_cl = NULL;
+	struct mei_cl_cb *cb = NULL;
+	ssize_t rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	mutex_lock(&dev->device_lock);
+	if (!mei_cl_is_connected(cl)) {
+		rets = -ENODEV;
+		goto out;
+	}
+
+	/* Check if we have an ME client device */
+	me_cl = mei_me_cl_by_uuid_id(dev, &cl->cl_uuid, cl->me_client_id);
+	if (!me_cl) {
+		rets = -ENOTTY;
+		goto out;
+	}
+
+	if (length > me_cl->props.max_msg_length) {
+		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:
+	mei_me_cl_put(me_cl);
+	mutex_unlock(&dev->device_lock);
+	if (rets < 0)
+		mei_io_cb_free(cb);
+
+	return rets;
+}
+
+ssize_t __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;
+	ssize_t rets;
+
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	mutex_lock(&dev->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;
+
+	if (list_empty(&cl->rd_completed) && !waitqueue_active(&cl->rx_wait)) {
+
+		mutex_unlock(&dev->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(&dev->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(&dev->device_lock);
+
+	return rets;
+}
+
+inline ssize_t __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length)
+{
+	return ___mei_cl_send(cl, buf, length, 0);
+}
+
+inline ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length)
+{
+	return ___mei_cl_send(cl, buf, length, 1);
+}
+
+ssize_t 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);
+
+ssize_t 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, NULL);
+}
+
+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, NULL);
+
+	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);
+
+	err = mei_cl_connect(cl, NULL);
+	if (err < 0) {
+		mutex_unlock(&dev->device_lock);
+		dev_err(dev->dev, "Could not connect to the ME client");
+
+		return err;
+	}
+
+	mutex_unlock(&dev->device_lock);
+
+	if (device->event_cb)
+		mei_cl_read_start(device->cl, 0, NULL);
+
+	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;
+
+	if (device->ops && device->ops->disable)
+		device->ops->disable(device);
+
+	device->event_cb = NULL;
+
+	mutex_lock(&dev->device_lock);
+
+	if (!mei_cl_is_connected(cl)) {
+		dev_err(dev->dev, "Already disconnected");
+		err = 0;
+		goto out;
+	}
+
+	cl->state = MEI_FILE_DISCONNECTING;
+
+	err = mei_cl_disconnect(cl);
+	if (err < 0) {
+		dev_err(dev->dev, "Could not disconnect from the ME client");
+		goto out;
+	}
+
+	/* Flush queues and remove any pending read */
+	mei_cl_flush_queues(cl, NULL);
+
+out:
+	mutex_unlock(&dev->device_lock);
+	return err;
+
+}
+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);
+}
+
+void mei_cl_bus_remove_devices(struct mei_device *dev)
+{
+	struct mei_cl *cl, *next;
+
+	mutex_lock(&dev->device_lock);
+	list_for_each_entry_safe(cl, next, &dev->device_list, device_link) {
+		if (cl->device)
+			mei_cl_remove_device(cl->device);
+
+		list_del(&cl->device_link);
+		mei_cl_unlink(cl);
+		kfree(cl);
+	}
+	mutex_unlock(&dev->device_lock);
+}
+
+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);
+}