Merge tag 'rpmsg-v4.11' of git://github.com/andersson/remoteproc (1db934a5) · Commits · 戴 / test

Documentation/ioctl/ioctl-number.txt

+1 −0

Original line number	Diff line number	Diff line
		@@ -321,6 +321,7 @@ Code Seq#(hex) Include File Comments
		0xB1 00-1F PPPoX <mailto:mostrows@styx.uwaterloo.ca>
		0xB3 00 linux/mmc/ioctl.h
		0xB4 00-0F linux/gpio.h <mailto:linux-gpio@vger.kernel.org>
		0xB5 00-0F uapi/linux/rpmsg.h <mailto:linux-remoteproc@vger.kernel.org>
		0xC0 00-0F linux/usb/iowarrior.h
		0xCA 00-0F uapi/misc/cxl.h
		0xCA 80-8F uapi/scsi/cxlflash_ioctl.h

drivers/rpmsg/Kconfig

+9 −0

Original line number	Diff line number	Diff line
		@@ -4,6 +4,15 @@ menu "Rpmsg drivers"
		config RPMSG
		tristate

		config RPMSG_CHAR
		tristate "RPMSG device interface"
		depends on RPMSG
		depends on NET
		help
		Say Y here to export rpmsg endpoints as device files, usually found
		in /dev. They make it possible for user-space programs to send and
		receive rpmsg packets.

		config RPMSG_QCOM_SMD
		tristate "Qualcomm Shared Memory Driver (SMD)"
		depends on QCOM_SMEM

drivers/rpmsg/Makefile

+1 −0

Original line number	Diff line number	Diff line
		obj-$(CONFIG_RPMSG) += rpmsg_core.o
		obj-$(CONFIG_RPMSG_CHAR) += rpmsg_char.o
		obj-$(CONFIG_RPMSG_QCOM_SMD) += qcom_smd.o
		obj-$(CONFIG_RPMSG_VIRTIO) += virtio_rpmsg_bus.o

drivers/rpmsg/qcom_smd.c

+58 −0

Original line number	Diff line number	Diff line
		@@ -117,6 +117,8 @@ static const struct {
		struct qcom_smd_edge {
		struct device dev;

		const char *name;

		struct device_node *of_node;
		unsigned edge_id;
		unsigned remote_pid;
		@@ -917,6 +919,21 @@ static int qcom_smd_trysend(struct rpmsg_endpoint ept, void data, int len)
		return __qcom_smd_send(qsept->qsch, data, len, false);
		}

		static unsigned int qcom_smd_poll(struct rpmsg_endpoint *ept,
		struct file filp, poll_table wait)
		{
		struct qcom_smd_endpoint *qsept = to_smd_endpoint(ept);
		struct qcom_smd_channel *channel = qsept->qsch;
		unsigned int mask = 0;

		poll_wait(filp, &channel->fblockread_event, wait);

		if (qcom_smd_get_tx_avail(channel) > 20)
		mask \|= POLLOUT \| POLLWRNORM;

		return mask;
		}

		/*
		* Finds the device_node for the smd child interested in this channel.
		*/
		@@ -949,6 +966,7 @@ static const struct rpmsg_endpoint_ops qcom_smd_endpoint_ops = {
		.destroy_ept = qcom_smd_destroy_ept,
		.send = qcom_smd_send,
		.trysend = qcom_smd_trysend,
		.poll = qcom_smd_poll,
		};

		/*
		@@ -984,6 +1002,20 @@ static int qcom_smd_create_device(struct qcom_smd_channel *channel)
		return rpmsg_register_device(rpdev);
		}

		static int qcom_smd_create_chrdev(struct qcom_smd_edge *edge)
		{
		struct qcom_smd_device *qsdev;

		qsdev = kzalloc(sizeof(*qsdev), GFP_KERNEL);
		if (!qsdev)
		return -ENOMEM;

		qsdev->edge = edge;
		qsdev->rpdev.ops = &qcom_smd_device_ops;
		qsdev->rpdev.dev.parent = &edge->dev;
		return rpmsg_chrdev_register_device(&qsdev->rpdev);
		}

		/*
		* Allocate the qcom_smd_channel object for a newly found smd channel,
		* retrieving and validating the smem items involved.
		@@ -1248,6 +1280,10 @@ static int qcom_smd_parse_edge(struct device *dev,
		return -EINVAL;
		}

		ret = of_property_read_string(node, "label", &edge->name);
		if (ret < 0)
		edge->name = node->name;

		irq = irq_of_parse_and_map(node, 0);
		if (irq < 0) {
		dev_err(dev, "required smd interrupt missing\n");
		@@ -1285,6 +1321,21 @@ static void qcom_smd_edge_release(struct device *dev)
		kfree(edge);
		}

		static ssize_t rpmsg_name_show(struct device *dev,
		struct device_attribute attr, char buf)
		{
		struct qcom_smd_edge *edge = to_smd_edge(dev);

		return sprintf(buf, "%s\n", edge->name);
		}
		static DEVICE_ATTR_RO(rpmsg_name);

		static struct attribute *qcom_smd_edge_attrs[] = {
		&dev_attr_rpmsg_name.attr,
		NULL
		};
		ATTRIBUTE_GROUPS(qcom_smd_edge);

		/**
		* qcom_smd_register_edge() - register an edge based on an device_node
		* @parent: parent device for the edge
		@@ -1306,6 +1357,7 @@ struct qcom_smd_edge qcom_smd_register_edge(struct device parent,

		edge->dev.parent = parent;
		edge->dev.release = qcom_smd_edge_release;
		edge->dev.groups = qcom_smd_edge_groups;
		dev_set_name(&edge->dev, "%s:%s", dev_name(parent), node->name);
		ret = device_register(&edge->dev);
		if (ret) {
		@@ -1319,6 +1371,12 @@ struct qcom_smd_edge qcom_smd_register_edge(struct device parent,
		goto unregister_dev;
		}

		ret = qcom_smd_create_chrdev(edge);
		if (ret) {
		dev_err(&edge->dev, "failed to register chrdev for edge\n");
		goto unregister_dev;
		}

		schedule_work(&edge->scan_work);

		return edge;

drivers/rpmsg/rpmsg_char.c

0 → 100644

+584 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (c) 2016, Linaro Ltd.
		* Copyright (c) 2012, Michal Simek <monstr@monstr.eu>
		* Copyright (c) 2012, PetaLogix
		* Copyright (c) 2011, Texas Instruments, Inc.
		* Copyright (c) 2011, Google, Inc.
		*
		* Based on rpmsg performance statistics driver by Michal Simek, which in turn
		* was based on TI & Google OMX rpmsg driver.
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License version 2 and
		* only version 2 as published by the Free Software Foundation.
		*
		* This program is distributed in the hope that 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/cdev.h>
		#include <linux/device.h>
		#include <linux/fs.h>
		#include <linux/idr.h>
		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/poll.h>
		#include <linux/rpmsg.h>
		#include <linux/skbuff.h>
		#include <linux/slab.h>
		#include <linux/uaccess.h>
		#include <uapi/linux/rpmsg.h>

		#include "rpmsg_internal.h"

		#define RPMSG_DEV_MAX (MINORMASK + 1)

		static dev_t rpmsg_major;
		static struct class *rpmsg_class;

		static DEFINE_IDA(rpmsg_ctrl_ida);
		static DEFINE_IDA(rpmsg_ept_ida);
		static DEFINE_IDA(rpmsg_minor_ida);

		#define dev_to_eptdev(dev) container_of(dev, struct rpmsg_eptdev, dev)
		#define cdev_to_eptdev(i_cdev) container_of(i_cdev, struct rpmsg_eptdev, cdev)

		#define dev_to_ctrldev(dev) container_of(dev, struct rpmsg_ctrldev, dev)
		#define cdev_to_ctrldev(i_cdev) container_of(i_cdev, struct rpmsg_ctrldev, cdev)

		/**
		* struct rpmsg_ctrldev - control device for instantiating endpoint devices
		* @rpdev: underlaying rpmsg device
		* @cdev: cdev for the ctrl device
		* @dev: device for the ctrl device
		*/
		struct rpmsg_ctrldev {
		struct rpmsg_device *rpdev;
		struct cdev cdev;
		struct device dev;
		};

		/**
		* struct rpmsg_eptdev - endpoint device context
		* @dev: endpoint device
		* @cdev: cdev for the endpoint device
		* @rpdev: underlaying rpmsg device
		* @chinfo: info used to open the endpoint
		* @ept_lock: synchronization of @ept modifications
		* @ept: rpmsg endpoint reference, when open
		* @queue_lock: synchronization of @queue operations
		* @queue: incoming message queue
		* @readq: wait object for incoming queue
		*/
		struct rpmsg_eptdev {
		struct device dev;
		struct cdev cdev;

		struct rpmsg_device *rpdev;
		struct rpmsg_channel_info chinfo;

		struct mutex ept_lock;
		struct rpmsg_endpoint *ept;

		spinlock_t queue_lock;
		struct sk_buff_head queue;
		wait_queue_head_t readq;
		};

		static int rpmsg_eptdev_destroy(struct device dev, void data)
		{
		struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev);

		mutex_lock(&eptdev->ept_lock);
		if (eptdev->ept) {
		rpmsg_destroy_ept(eptdev->ept);
		eptdev->ept = NULL;
		}
		mutex_unlock(&eptdev->ept_lock);

		/* wake up any blocked readers */
		wake_up_interruptible(&eptdev->readq);

		device_del(&eptdev->dev);
		put_device(&eptdev->dev);

		return 0;
		}

		static int rpmsg_ept_cb(struct rpmsg_device rpdev, void buf, int len,
		void *priv, u32 addr)
		{
		struct rpmsg_eptdev *eptdev = priv;
		struct sk_buff *skb;

		skb = alloc_skb(len, GFP_ATOMIC);
		if (!skb)
		return -ENOMEM;

		memcpy(skb_put(skb, len), buf, len);

		spin_lock(&eptdev->queue_lock);
		skb_queue_tail(&eptdev->queue, skb);
		spin_unlock(&eptdev->queue_lock);

		/* wake up any blocking processes, waiting for new data */
		wake_up_interruptible(&eptdev->readq);

		return 0;
		}

		static int rpmsg_eptdev_open(struct inode inode, struct file filp)
		{
		struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev);
		struct rpmsg_endpoint *ept;
		struct rpmsg_device *rpdev = eptdev->rpdev;
		struct device *dev = &eptdev->dev;

		get_device(dev);

		ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo);
		if (!ept) {
		dev_err(dev, "failed to open %s\n", eptdev->chinfo.name);
		put_device(dev);
		return -EINVAL;
		}

		eptdev->ept = ept;
		filp->private_data = eptdev;

		return 0;
		}

		static int rpmsg_eptdev_release(struct inode inode, struct file filp)
		{
		struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev);
		struct device *dev = &eptdev->dev;
		struct sk_buff *skb;

		/* Close the endpoint, if it's not already destroyed by the parent */
		mutex_lock(&eptdev->ept_lock);
		if (eptdev->ept) {
		rpmsg_destroy_ept(eptdev->ept);
		eptdev->ept = NULL;
		}
		mutex_unlock(&eptdev->ept_lock);

		/* Discard all SKBs */
		while (!skb_queue_empty(&eptdev->queue)) {
		skb = skb_dequeue(&eptdev->queue);
		kfree_skb(skb);
		}

		put_device(dev);

		return 0;
		}

		static ssize_t rpmsg_eptdev_read(struct file filp, char __user buf,
		size_t len, loff_t *f_pos)
		{
		struct rpmsg_eptdev *eptdev = filp->private_data;
		unsigned long flags;
		struct sk_buff *skb;
		int use;

		if (!eptdev->ept)
		return -EPIPE;

		spin_lock_irqsave(&eptdev->queue_lock, flags);

		/* Wait for data in the queue */
		if (skb_queue_empty(&eptdev->queue)) {
		spin_unlock_irqrestore(&eptdev->queue_lock, flags);

		if (filp->f_flags & O_NONBLOCK)
		return -EAGAIN;

		/* Wait until we get data or the endpoint goes away */
		if (wait_event_interruptible(eptdev->readq,
		!skb_queue_empty(&eptdev->queue) \|\|
		!eptdev->ept))
		return -ERESTARTSYS;

		/* We lost the endpoint while waiting */
		if (!eptdev->ept)
		return -EPIPE;

		spin_lock_irqsave(&eptdev->queue_lock, flags);
		}

		skb = skb_dequeue(&eptdev->queue);
		spin_unlock_irqrestore(&eptdev->queue_lock, flags);
		if (!skb)
		return -EFAULT;

		use = min_t(size_t, len, skb->len);
		if (copy_to_user(buf, skb->data, use))
		use = -EFAULT;

		kfree_skb(skb);

		return use;
		}

		static ssize_t rpmsg_eptdev_write(struct file filp, const char __user buf,
		size_t len, loff_t *f_pos)
		{
		struct rpmsg_eptdev *eptdev = filp->private_data;
		void *kbuf;
		int ret;

		kbuf = memdup_user(buf, len);
		if (IS_ERR(kbuf))
		return PTR_ERR(kbuf);

		if (mutex_lock_interruptible(&eptdev->ept_lock)) {
		ret = -ERESTARTSYS;
		goto free_kbuf;
		}

		if (!eptdev->ept) {
		ret = -EPIPE;
		goto unlock_eptdev;
		}

		if (filp->f_flags & O_NONBLOCK)
		ret = rpmsg_trysend(eptdev->ept, kbuf, len);
		else
		ret = rpmsg_send(eptdev->ept, kbuf, len);

		unlock_eptdev:
		mutex_unlock(&eptdev->ept_lock);

		free_kbuf:
		kfree(kbuf);
		return ret < 0 ? ret : len;
		}

		static unsigned int rpmsg_eptdev_poll(struct file filp, poll_table wait)
		{
		struct rpmsg_eptdev *eptdev = filp->private_data;
		unsigned int mask = 0;

		if (!eptdev->ept)
		return POLLERR;

		poll_wait(filp, &eptdev->readq, wait);

		if (!skb_queue_empty(&eptdev->queue))
		mask \|= POLLIN \| POLLRDNORM;

		mask \|= rpmsg_poll(eptdev->ept, filp, wait);

		return mask;
		}

		static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd,
		unsigned long arg)
		{
		struct rpmsg_eptdev *eptdev = fp->private_data;

		if (cmd != RPMSG_DESTROY_EPT_IOCTL)
		return -EINVAL;

		return rpmsg_eptdev_destroy(&eptdev->dev, NULL);
		}

		static const struct file_operations rpmsg_eptdev_fops = {
		.owner = THIS_MODULE,
		.open = rpmsg_eptdev_open,
		.release = rpmsg_eptdev_release,
		.read = rpmsg_eptdev_read,
		.write = rpmsg_eptdev_write,
		.poll = rpmsg_eptdev_poll,
		.unlocked_ioctl = rpmsg_eptdev_ioctl,
		};

		static ssize_t name_show(struct device dev, struct device_attribute attr,
		char *buf)
		{
		struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);

		return sprintf(buf, "%s\n", eptdev->chinfo.name);
		}
		static DEVICE_ATTR_RO(name);

		static ssize_t src_show(struct device dev, struct device_attribute attr,
		char *buf)
		{
		struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);

		return sprintf(buf, "%d\n", eptdev->chinfo.src);
		}
		static DEVICE_ATTR_RO(src);

		static ssize_t dst_show(struct device dev, struct device_attribute attr,
		char *buf)
		{
		struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);

		return sprintf(buf, "%d\n", eptdev->chinfo.dst);
		}
		static DEVICE_ATTR_RO(dst);

		static struct attribute *rpmsg_eptdev_attrs[] = {
		&dev_attr_name.attr,
		&dev_attr_src.attr,
		&dev_attr_dst.attr,
		NULL
		};
		ATTRIBUTE_GROUPS(rpmsg_eptdev);

		static void rpmsg_eptdev_release_device(struct device *dev)
		{
		struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev);

		ida_simple_remove(&rpmsg_ept_ida, dev->id);
		ida_simple_remove(&rpmsg_minor_ida, MINOR(eptdev->dev.devt));
		cdev_del(&eptdev->cdev);
		kfree(eptdev);
		}

		static int rpmsg_eptdev_create(struct rpmsg_ctrldev *ctrldev,
		struct rpmsg_channel_info chinfo)
		{
		struct rpmsg_device *rpdev = ctrldev->rpdev;
		struct rpmsg_eptdev *eptdev;
		struct device *dev;
		int ret;

		eptdev = kzalloc(sizeof(*eptdev), GFP_KERNEL);
		if (!eptdev)
		return -ENOMEM;

		dev = &eptdev->dev;
		eptdev->rpdev = rpdev;
		eptdev->chinfo = chinfo;

		mutex_init(&eptdev->ept_lock);
		spin_lock_init(&eptdev->queue_lock);
		skb_queue_head_init(&eptdev->queue);
		init_waitqueue_head(&eptdev->readq);

		device_initialize(dev);
		dev->class = rpmsg_class;
		dev->parent = &ctrldev->dev;
		dev->groups = rpmsg_eptdev_groups;
		dev_set_drvdata(dev, eptdev);

		cdev_init(&eptdev->cdev, &rpmsg_eptdev_fops);
		eptdev->cdev.owner = THIS_MODULE;

		ret = ida_simple_get(&rpmsg_minor_ida, 0, RPMSG_DEV_MAX, GFP_KERNEL);
		if (ret < 0)
		goto free_eptdev;
		dev->devt = MKDEV(MAJOR(rpmsg_major), ret);

		ret = ida_simple_get(&rpmsg_ept_ida, 0, 0, GFP_KERNEL);
		if (ret < 0)
		goto free_minor_ida;
		dev->id = ret;
		dev_set_name(dev, "rpmsg%d", ret);

		ret = cdev_add(&eptdev->cdev, dev->devt, 1);
		if (ret)
		goto free_ept_ida;

		/* We can now rely on the release function for cleanup */
		dev->release = rpmsg_eptdev_release_device;

		ret = device_add(dev);
		if (ret) {
		dev_err(dev, "device_register failed: %d\n", ret);
		put_device(dev);
		}

		return ret;

		free_ept_ida:
		ida_simple_remove(&rpmsg_ept_ida, dev->id);
		free_minor_ida:
		ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt));
		free_eptdev:
		put_device(dev);
		kfree(eptdev);

		return ret;
		}

		static int rpmsg_ctrldev_open(struct inode inode, struct file filp)
		{
		struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev);

		get_device(&ctrldev->dev);
		filp->private_data = ctrldev;

		return 0;
		}

		static int rpmsg_ctrldev_release(struct inode inode, struct file filp)
		{
		struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev);

		put_device(&ctrldev->dev);

		return 0;
		}

		static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd,
		unsigned long arg)
		{
		struct rpmsg_ctrldev *ctrldev = fp->private_data;
		void __user argp = (void __user )arg;
		struct rpmsg_endpoint_info eptinfo;
		struct rpmsg_channel_info chinfo;

		if (cmd != RPMSG_CREATE_EPT_IOCTL)
		return -EINVAL;

		if (copy_from_user(&eptinfo, argp, sizeof(eptinfo)))
		return -EFAULT;

		memcpy(chinfo.name, eptinfo.name, RPMSG_NAME_SIZE);
		chinfo.name[RPMSG_NAME_SIZE-1] = '\0';
		chinfo.src = eptinfo.src;
		chinfo.dst = eptinfo.dst;

		return rpmsg_eptdev_create(ctrldev, chinfo);
		};

		static const struct file_operations rpmsg_ctrldev_fops = {
		.owner = THIS_MODULE,
		.open = rpmsg_ctrldev_open,
		.release = rpmsg_ctrldev_release,
		.unlocked_ioctl = rpmsg_ctrldev_ioctl,
		};

		static void rpmsg_ctrldev_release_device(struct device *dev)
		{
		struct rpmsg_ctrldev *ctrldev = dev_to_ctrldev(dev);

		ida_simple_remove(&rpmsg_ctrl_ida, dev->id);
		ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt));
		cdev_del(&ctrldev->cdev);
		kfree(ctrldev);
		}

		static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev)
		{
		struct rpmsg_ctrldev *ctrldev;
		struct device *dev;
		int ret;

		ctrldev = kzalloc(sizeof(*ctrldev), GFP_KERNEL);
		if (!ctrldev)
		return -ENOMEM;

		ctrldev->rpdev = rpdev;

		dev = &ctrldev->dev;
		device_initialize(dev);
		dev->parent = &rpdev->dev;
		dev->class = rpmsg_class;

		cdev_init(&ctrldev->cdev, &rpmsg_ctrldev_fops);
		ctrldev->cdev.owner = THIS_MODULE;

		ret = ida_simple_get(&rpmsg_minor_ida, 0, RPMSG_DEV_MAX, GFP_KERNEL);
		if (ret < 0)
		goto free_ctrldev;
		dev->devt = MKDEV(MAJOR(rpmsg_major), ret);

		ret = ida_simple_get(&rpmsg_ctrl_ida, 0, 0, GFP_KERNEL);
		if (ret < 0)
		goto free_minor_ida;
		dev->id = ret;
		dev_set_name(&ctrldev->dev, "rpmsg_ctrl%d", ret);

		ret = cdev_add(&ctrldev->cdev, dev->devt, 1);
		if (ret)
		goto free_ctrl_ida;

		/* We can now rely on the release function for cleanup */
		dev->release = rpmsg_ctrldev_release_device;

		ret = device_add(dev);
		if (ret) {
		dev_err(&rpdev->dev, "device_register failed: %d\n", ret);
		put_device(dev);
		}

		dev_set_drvdata(&rpdev->dev, ctrldev);

		return ret;

		free_ctrl_ida:
		ida_simple_remove(&rpmsg_ctrl_ida, dev->id);
		free_minor_ida:
		ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt));
		free_ctrldev:
		put_device(dev);
		kfree(ctrldev);

		return ret;
		}

		static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev)
		{
		struct rpmsg_ctrldev *ctrldev = dev_get_drvdata(&rpdev->dev);
		int ret;

		/* Destroy all endpoints */
		ret = device_for_each_child(&ctrldev->dev, NULL, rpmsg_eptdev_destroy);
		if (ret)
		dev_warn(&rpdev->dev, "failed to nuke endpoints: %d\n", ret);

		device_del(&ctrldev->dev);
		put_device(&ctrldev->dev);
		}

		static struct rpmsg_driver rpmsg_chrdev_driver = {
		.probe = rpmsg_chrdev_probe,
		.remove = rpmsg_chrdev_remove,
		.drv = {
		.name = "rpmsg_chrdev",
		},
		};

		static int rpmsg_char_init(void)
		{
		int ret;

		ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg");
		if (ret < 0) {
		pr_err("rpmsg: failed to allocate char dev region\n");
		return ret;
		}

		rpmsg_class = class_create(THIS_MODULE, "rpmsg");
		if (IS_ERR(rpmsg_class)) {
		pr_err("failed to create rpmsg class\n");
		unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
		return PTR_ERR(rpmsg_class);
		}

		ret = register_rpmsg_driver(&rpmsg_chrdev_driver);
		if (ret < 0) {
		pr_err("rpmsgchr: failed to register rpmsg driver\n");
		class_destroy(rpmsg_class);
		unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
		}

		return ret;
		}
		postcore_initcall(rpmsg_char_init);

		static void rpmsg_chrdev_exit(void)
		{
		unregister_rpmsg_driver(&rpmsg_chrdev_driver);
		class_destroy(rpmsg_class);
		unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
		}
		module_exit(rpmsg_chrdev_exit);
		MODULE_LICENSE("GPL v2");

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