[deliverable/linux.git] / drivers / misc / mei / bus.c

/*
 * 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;
	struct mei_cl_cb *cb;
	ssize_t 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 */
	me_cl = mei_me_cl_by_uuid_id(dev, &cl->cl_uuid, cl->me_client_id);
	if (!me_cl)
		return -ENOTTY;

	if (length > me_cl->props.max_msg_length)
		return -EFBIG;

	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;
}

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);

	if (!cl->read_cb) {
		rets = mei_cl_read_start(cl, length);
		if (rets < 0)
			goto out;
	}

	if (cl->reading_state != MEI_READ_COMPLETE &&
	    !waitqueue_active(&cl->rx_wait)) {

		mutex_unlock(&dev->device_lock);

		if (wait_event_interruptible(cl->rx_wait,
				cl->reading_state == MEI_READ_COMPLETE  ||
				mei_cl_is_transitioning(cl))) {

			if (signal_pending(current))
				return -EINTR;
			return -ERESTARTSYS;
		}

		mutex_lock(&dev->device_lock);
	}

	cb = cl->read_cb;

	if (cl->reading_state != MEI_READ_COMPLETE) {
		rets = 0;
		goto out;
	}

	r_length = min_t(size_t, length, cb->buf_idx);
	memcpy(buf, cb->response_buffer.data, r_length);
	rets = r_length;

	mei_io_cb_free(cb);
	cl->reading_state = MEI_IDLE;
	cl->read_cb = NULL;

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);
}

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);

	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 && !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->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->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;
		}
	}

	device->event_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);
}

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);
}
Commit	Line	Data
e5354107 SO	1	/*
	2	* Intel Management Engine Interface (Intel MEI) Linux driver
	3	* Copyright (c) 2012-2013, Intel Corporation.
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms and conditions of the GNU General Public License,
	7	* version 2, as published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope it will be useful, but WITHOUT
	10	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	11	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	12	* more details.
	13	*
	14	*/
	15
	16	#include <linux/module.h>
	17	#include <linux/device.h>
	18	#include <linux/kernel.h>
3e833295	19	#include <linux/sched.h>
e5354107 SO	20	#include <linux/init.h>
	21	#include <linux/errno.h>
	22	#include <linux/slab.h>
	23	#include <linux/mutex.h>
	24	#include <linux/interrupt.h>
e5354107 SO	25	#include <linux/mei_cl_bus.h>
	26
	27	#include "mei_dev.h"
3e833295	28	#include "client.h"
e5354107 SO	29
	30	#define to_mei_cl_driver(d) container_of(d, struct mei_cl_driver, driver)
	31	#define to_mei_cl_device(d) container_of(d, struct mei_cl_device, dev)
	32
	33	static int mei_cl_device_match(struct device dev, struct device_driver drv)
	34	{
	35	struct mei_cl_device *device = to_mei_cl_device(dev);
	36	struct mei_cl_driver *driver = to_mei_cl_driver(drv);
	37	const struct mei_cl_device_id *id;
	38
	39	if (!device)
	40	return 0;
	41
	42	if (!driver \|\| !driver->id_table)
	43	return 0;
	44
	45	id = driver->id_table;
	46
	47	while (id->name[0]) {
8b613bb8	48	if (!strncmp(dev_name(dev), id->name, sizeof(id->name)))
e5354107 SO	49	return 1;
	50
	51	id++;
	52	}
	53
	54	return 0;
	55	}
	56
	57	static int mei_cl_device_probe(struct device *dev)
	58	{
	59	struct mei_cl_device *device = to_mei_cl_device(dev);
	60	struct mei_cl_driver *driver;
	61	struct mei_cl_device_id id;
	62
	63	if (!device)
	64	return 0;
	65
	66	driver = to_mei_cl_driver(dev->driver);
	67	if (!driver \|\| !driver->probe)
	68	return -ENODEV;
	69
	70	dev_dbg(dev, "Device probe\n");
	71
cfda2794	72	strlcpy(id.name, dev_name(dev), sizeof(id.name));
e5354107 SO	73
	74	return driver->probe(device, &id);
	75	}
	76
	77	static int mei_cl_device_remove(struct device *dev)
	78	{
	79	struct mei_cl_device *device = to_mei_cl_device(dev);
	80	struct mei_cl_driver *driver;
	81
	82	if (!device \|\| !dev->driver)
	83	return 0;
	84
3e833295 SO	85	if (device->event_cb) {
	86	device->event_cb = NULL;
	87	cancel_work_sync(&device->event_work);
	88	}
	89
e5354107 SO	90	driver = to_mei_cl_driver(dev->driver);
	91	if (!driver->remove) {
	92	dev->driver = NULL;
	93
	94	return 0;
	95	}
	96
	97	return driver->remove(device);
	98	}
	99
	100	static ssize_t modalias_show(struct device dev, struct device_attribute a,
	101	char *buf)
	102	{
	103	int len;
	104
	105	len = snprintf(buf, PAGE_SIZE, "mei:%s\n", dev_name(dev));
	106
	107	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
	108	}
32f389ec	109	static DEVICE_ATTR_RO(modalias);
e5354107	110
32f389ec GKH	111	static struct attribute *mei_cl_dev_attrs[] = {
	112	&dev_attr_modalias.attr,
	113	NULL,
e5354107	114	};
32f389ec	115	ATTRIBUTE_GROUPS(mei_cl_dev);
e5354107 SO	116
	117	static int mei_cl_uevent(struct device dev, struct kobj_uevent_env env)
	118	{
	119	if (add_uevent_var(env, "MODALIAS=mei:%s", dev_name(dev)))
	120	return -ENOMEM;
	121
	122	return 0;
	123	}
	124
	125	static struct bus_type mei_cl_bus_type = {
	126	.name = "mei",
32f389ec	127	.dev_groups = mei_cl_dev_groups,
e5354107 SO	128	.match = mei_cl_device_match,
	129	.probe = mei_cl_device_probe,
	130	.remove = mei_cl_device_remove,
	131	.uevent = mei_cl_uevent,
	132	};
	133
	134	static void mei_cl_dev_release(struct device *dev)
	135	{
	136	kfree(to_mei_cl_device(dev));
	137	}
	138
	139	static struct device_type mei_cl_device_type = {
	140	.release = mei_cl_dev_release,
	141	};
	142
a176c24d	143	struct mei_cl mei_cl_bus_find_cl_by_uuid(struct mei_device dev,
a7b71bc0 SO	144	uuid_le uuid)
a7b71bc0 SO	145	{
31f88f57	146	struct mei_cl *cl;
a7b71bc0	147
31f88f57	148	list_for_each_entry(cl, &dev->device_list, device_link) {
d880f329	149	if (!uuid_le_cmp(uuid, cl->cl_uuid))
a7b71bc0 SO	150	return cl;
	151	}
	152
	153	return NULL;
	154	}
	155	struct mei_cl_device mei_cl_add_device(struct mei_device dev,
e46980a1 SO	156	uuid_le uuid, char *name,
e46980a1 SO	157	struct mei_cl_ops *ops)
e5354107 SO	158	{
e5354107 SO	159	struct mei_cl_device *device;
a7b71bc0	160	struct mei_cl *cl;
e5354107 SO	161	int status;
e5354107 SO	162
a176c24d	163	cl = mei_cl_bus_find_cl_by_uuid(dev, uuid);
a7b71bc0 SO	164	if (cl == NULL)
	165	return NULL;
	166
e5354107 SO	167	device = kzalloc(sizeof(struct mei_cl_device), GFP_KERNEL);
	168	if (!device)
	169	return NULL;
	170
a7b71bc0	171	device->cl = cl;
e46980a1	172	device->ops = ops;
a7b71bc0	173
2bf94cab	174	device->dev.parent = dev->dev;
e5354107 SO	175	device->dev.bus = &mei_cl_bus_type;
	176	device->dev.type = &mei_cl_device_type;
	177
	178	dev_set_name(&device->dev, "%s", name);
	179
	180	status = device_register(&device->dev);
a7b71bc0	181	if (status) {
2bf94cab	182	dev_err(dev->dev, "Failed to register MEI device\n");
a7b71bc0 SO	183	kfree(device);
	184	return NULL;
	185	}
	186
	187	cl->device = device;
e5354107 SO	188
	189	dev_dbg(&device->dev, "client %s registered\n", name);
	190
	191	return device;
e5354107 SO	192	}
	193	EXPORT_SYMBOL_GPL(mei_cl_add_device);
	194
	195	void mei_cl_remove_device(struct mei_cl_device *device)
	196	{
	197	device_unregister(&device->dev);
	198	}
	199	EXPORT_SYMBOL_GPL(mei_cl_remove_device);
333e4ee0 SO	200
	201	int __mei_cl_driver_register(struct mei_cl_driver driver, struct module owner)
	202	{
	203	int err;
	204
	205	driver->driver.name = driver->name;
	206	driver->driver.owner = owner;
	207	driver->driver.bus = &mei_cl_bus_type;
	208
	209	err = driver_register(&driver->driver);
	210	if (err)
	211	return err;
	212
	213	pr_debug("mei: driver [%s] registered\n", driver->driver.name);
	214
	215	return 0;
	216	}
	217	EXPORT_SYMBOL_GPL(__mei_cl_driver_register);
	218
	219	void mei_cl_driver_unregister(struct mei_cl_driver *driver)
	220	{
	221	driver_unregister(&driver->driver);
	222
	223	pr_debug("mei: driver [%s] unregistered\n", driver->driver.name);
	224	}
	225	EXPORT_SYMBOL_GPL(mei_cl_driver_unregister);
3e833295	226
39db74ce	227	static ssize_t ___mei_cl_send(struct mei_cl cl, u8 buf, size_t length,
44d88d91	228	bool blocking)
3e833295 SO	229	{
3e833295 SO	230	struct mei_device *dev;
d320832f	231	struct mei_me_client *me_cl;
3e833295	232	struct mei_cl_cb *cb;
39db74ce	233	ssize_t rets;
3e833295 SO	234
	235	if (WARN_ON(!cl \|\| !cl->dev))
	236	return -ENODEV;
	237
4234a6de TW	238	dev = cl->dev;
4234a6de TW	239
3e833295 SO	240	if (cl->state != MEI_FILE_CONNECTED)
	241	return -ENODEV;
	242
4234a6de	243	/* Check if we have an ME client device */
d880f329	244	me_cl = mei_me_cl_by_uuid_id(dev, &cl->cl_uuid, cl->me_client_id);
d320832f TW	245	if (!me_cl)
d320832f TW	246	return -ENOTTY;
4234a6de	247
d320832f	248	if (length > me_cl->props.max_msg_length)
86113500	249	return -EFBIG;
4234a6de	250
3e833295 SO	251	cb = mei_io_cb_init(cl, NULL);
	252	if (!cb)
	253	return -ENOMEM;
	254
4234a6de TW	255	rets = mei_io_cb_alloc_req_buf(cb, length);
4234a6de TW	256	if (rets < 0) {
3e833295	257	mei_io_cb_free(cb);
4234a6de	258	return rets;
3e833295 SO	259	}
	260
	261	memcpy(cb->request_buffer.data, buf, length);
3e833295 SO	262
	263	mutex_lock(&dev->device_lock);
	264
4234a6de	265	rets = mei_cl_write(cl, cb, blocking);
3e833295 SO	266
3e833295 SO	267	mutex_unlock(&dev->device_lock);
4234a6de TW	268	if (rets < 0)
4234a6de TW	269	mei_io_cb_free(cb);
3e833295	270
4234a6de	271	return rets;
3e833295 SO	272	}
3e833295 SO	273
39db74ce	274	ssize_t __mei_cl_recv(struct mei_cl cl, u8 buf, size_t length)
3e833295 SO	275	{
	276	struct mei_device *dev;
	277	struct mei_cl_cb *cb;
	278	size_t r_length;
39db74ce	279	ssize_t rets;
3e833295 SO	280
	281	if (WARN_ON(!cl \|\| !cl->dev))
	282	return -ENODEV;
	283
	284	dev = cl->dev;
	285
	286	mutex_lock(&dev->device_lock);
	287
	288	if (!cl->read_cb) {
39db74ce TW	289	rets = mei_cl_read_start(cl, length);
	290	if (rets < 0)
	291	goto out;
3e833295 SO	292	}
	293
	294	if (cl->reading_state != MEI_READ_COMPLETE &&
	295	!waitqueue_active(&cl->rx_wait)) {
e2b31644	296
3e833295 SO	297	mutex_unlock(&dev->device_lock);
	298
	299	if (wait_event_interruptible(cl->rx_wait,
e2b31644 TW	300	cl->reading_state == MEI_READ_COMPLETE \|\|
	301	mei_cl_is_transitioning(cl))) {
	302
3e833295 SO	303	if (signal_pending(current))
	304	return -EINTR;
	305	return -ERESTARTSYS;
	306	}
	307
	308	mutex_lock(&dev->device_lock);
	309	}
	310
	311	cb = cl->read_cb;
	312
	313	if (cl->reading_state != MEI_READ_COMPLETE) {
39db74ce	314	rets = 0;
3e833295 SO	315	goto out;
	316	}
	317
	318	r_length = min_t(size_t, length, cb->buf_idx);
3e833295	319	memcpy(buf, cb->response_buffer.data, r_length);
39db74ce	320	rets = r_length;
3e833295 SO	321
	322	mei_io_cb_free(cb);
	323	cl->reading_state = MEI_IDLE;
	324	cl->read_cb = NULL;
	325
	326	out:
	327	mutex_unlock(&dev->device_lock);
	328
39db74ce	329	return rets;
3e833295 SO	330	}
3e833295 SO	331
39db74ce	332	inline ssize_t __mei_cl_async_send(struct mei_cl cl, u8 buf, size_t length)
44d88d91 SO	333	{
	334	return ___mei_cl_send(cl, buf, length, 0);
	335	}
	336
39db74ce	337	inline ssize_t __mei_cl_send(struct mei_cl cl, u8 buf, size_t length)
44d88d91 SO	338	{
	339	return ___mei_cl_send(cl, buf, length, 1);
	340	}
	341
39db74ce	342	ssize_t mei_cl_send(struct mei_cl_device device, u8 buf, size_t length)
3e833295	343	{
a7b71bc0	344	struct mei_cl *cl = device->cl;
3e833295	345
a7b71bc0 SO	346	if (cl == NULL)
a7b71bc0 SO	347	return -ENODEV;
3e833295 SO	348
	349	if (device->ops && device->ops->send)
	350	return device->ops->send(device, buf, length);
	351
	352	return __mei_cl_send(cl, buf, length);
	353	}
	354	EXPORT_SYMBOL_GPL(mei_cl_send);
	355
39db74ce	356	ssize_t mei_cl_recv(struct mei_cl_device device, u8 buf, size_t length)
3e833295	357	{
a7b71bc0	358	struct mei_cl *cl = device->cl;
3e833295	359
a7b71bc0 SO	360	if (cl == NULL)
a7b71bc0 SO	361	return -ENODEV;
3e833295 SO	362
	363	if (device->ops && device->ops->recv)
	364	return device->ops->recv(device, buf, length);
	365
	366	return __mei_cl_recv(cl, buf, length);
	367	}
	368	EXPORT_SYMBOL_GPL(mei_cl_recv);
	369
	370	static void mei_bus_event_work(struct work_struct *work)
	371	{
	372	struct mei_cl_device *device;
	373
	374	device = container_of(work, struct mei_cl_device, event_work);
	375
	376	if (device->event_cb)
	377	device->event_cb(device, device->events, device->event_context);
	378
	379	device->events = 0;
	380
	381	/* Prepare for the next read */
fcb136e1	382	mei_cl_read_start(device->cl, 0);
3e833295 SO	383	}
	384
	385	int mei_cl_register_event_cb(struct mei_cl_device *device,
	386	mei_cl_event_cb_t event_cb, void *context)
	387	{
	388	if (device->event_cb)
	389	return -EALREADY;
	390
	391	device->events = 0;
	392	device->event_cb = event_cb;
	393	device->event_context = context;
	394	INIT_WORK(&device->event_work, mei_bus_event_work);
	395
fcb136e1	396	mei_cl_read_start(device->cl, 0);
3e833295 SO	397
	398	return 0;
	399	}
	400	EXPORT_SYMBOL_GPL(mei_cl_register_event_cb);
cf3baefb	401
aa6aef21 SO	402	void mei_cl_get_drvdata(const struct mei_cl_device device)
	403	{
	404	return dev_get_drvdata(&device->dev);
	405	}
	406	EXPORT_SYMBOL_GPL(mei_cl_get_drvdata);
	407
	408	void mei_cl_set_drvdata(struct mei_cl_device device, void data)
	409	{
	410	dev_set_drvdata(&device->dev, data);
	411	}
	412	EXPORT_SYMBOL_GPL(mei_cl_set_drvdata);
	413
e46980a1 SO	414	int mei_cl_enable_device(struct mei_cl_device *device)
	415	{
	416	int err;
	417	struct mei_device *dev;
	418	struct mei_cl *cl = device->cl;
	419
	420	if (cl == NULL)
	421	return -ENODEV;
	422
	423	dev = cl->dev;
	424
	425	mutex_lock(&dev->device_lock);
	426
e46980a1 SO	427	err = mei_cl_connect(cl, NULL);
	428	if (err < 0) {
	429	mutex_unlock(&dev->device_lock);
2bf94cab	430	dev_err(dev->dev, "Could not connect to the ME client");
e46980a1 SO	431
	432	return err;
	433	}
	434
	435	mutex_unlock(&dev->device_lock);
	436
	437	if (device->event_cb && !cl->read_cb)
fcb136e1	438	mei_cl_read_start(device->cl, 0);
e46980a1 SO	439
	440	if (!device->ops \|\| !device->ops->enable)
	441	return 0;
	442
	443	return device->ops->enable(device);
	444	}
	445	EXPORT_SYMBOL_GPL(mei_cl_enable_device);
	446
	447	int mei_cl_disable_device(struct mei_cl_device *device)
	448	{
	449	int err;
	450	struct mei_device *dev;
	451	struct mei_cl *cl = device->cl;
	452
	453	if (cl == NULL)
	454	return -ENODEV;
	455
	456	dev = cl->dev;
	457
	458	mutex_lock(&dev->device_lock);
	459
	460	if (cl->state != MEI_FILE_CONNECTED) {
	461	mutex_unlock(&dev->device_lock);
2bf94cab	462	dev_err(dev->dev, "Already disconnected");
e46980a1 SO	463
	464	return 0;
	465	}
	466
	467	cl->state = MEI_FILE_DISCONNECTING;
	468
	469	err = mei_cl_disconnect(cl);
	470	if (err < 0) {
	471	mutex_unlock(&dev->device_lock);
2bf94cab	472	dev_err(dev->dev,
e46980a1 SO	473	"Could not disconnect from the ME client");
	474
	475	return err;
	476	}
	477
	478	/* Flush queues and remove any pending read */
	479	mei_cl_flush_queues(cl);
	480
	481	if (cl->read_cb) {
	482	struct mei_cl_cb *cb = NULL;
	483
	484	cb = mei_cl_find_read_cb(cl);
	485	/* Remove entry from read list */
	486	if (cb)
	487	list_del(&cb->list);
	488
	489	cb = cl->read_cb;
	490	cl->read_cb = NULL;
	491
	492	if (cb) {
	493	mei_io_cb_free(cb);
	494	cb = NULL;
	495	}
	496	}
	497
bbedf2fc SO	498	device->event_cb = NULL;
bbedf2fc SO	499
e46980a1 SO	500	mutex_unlock(&dev->device_lock);
	501
	502	if (!device->ops \|\| !device->ops->disable)
	503	return 0;
	504
	505	return device->ops->disable(device);
	506	}
	507	EXPORT_SYMBOL_GPL(mei_cl_disable_device);
	508
cf3baefb SO	509	void mei_cl_bus_rx_event(struct mei_cl *cl)
	510	{
	511	struct mei_cl_device *device = cl->device;
	512
	513	if (!device \|\| !device->event_cb)
	514	return;
	515
	516	set_bit(MEI_CL_EVENT_RX, &device->events);
	517
	518	schedule_work(&device->event_work);
	519	}
	520
48705693 TW	521	void mei_cl_bus_remove_devices(struct mei_device *dev)
	522	{
	523	struct mei_cl cl, next;
	524
	525	mutex_lock(&dev->device_lock);
	526	list_for_each_entry_safe(cl, next, &dev->device_list, device_link) {
	527	if (cl->device)
	528	mei_cl_remove_device(cl->device);
	529
	530	list_del(&cl->device_link);
	531	mei_cl_unlink(cl);
	532	kfree(cl);
	533	}
	534	mutex_unlock(&dev->device_lock);
	535	}
	536
cf3baefb SO	537	int __init mei_cl_bus_init(void)
	538	{
	539	return bus_register(&mei_cl_bus_type);
	540	}
	541
	542	void __exit mei_cl_bus_exit(void)
	543	{
	544	bus_unregister(&mei_cl_bus_type);
	545	}