[PATCH v4 3/4] rpmsg: Move the rpmsg control device from rpmsg_char to rpmsg_ctrl

From: Arnaud Pouliquen
Date: Mon May 17 2021 - 13:15:51 EST


Create the rpmsg_ctrl.c module and move the code related to the
rpmsg_ctrldev device in this new module.

Add the dependency between rpmsg_char and rpmsg_ctrl in the
kconfig file.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>

---
Update from V3:

- reintroduce includes that declare the facilities used in rpmsg_ctrl.c.
---
drivers/rpmsg/Kconfig | 9 ++
drivers/rpmsg/Makefile | 1 +
drivers/rpmsg/rpmsg_char.c | 170 +----------------------------
drivers/rpmsg/rpmsg_char.h | 2 +
drivers/rpmsg/rpmsg_ctrl.c | 215 +++++++++++++++++++++++++++++++++++++
5 files changed, 229 insertions(+), 168 deletions(-)
create mode 100644 drivers/rpmsg/rpmsg_ctrl.c

diff --git a/drivers/rpmsg/Kconfig b/drivers/rpmsg/Kconfig
index 0b4407abdf13..d822ec9ec692 100644
--- a/drivers/rpmsg/Kconfig
+++ b/drivers/rpmsg/Kconfig
@@ -10,11 +10,20 @@ config RPMSG_CHAR
tristate "RPMSG device interface"
depends on RPMSG
depends on NET
+ select RPMSG_CTRL
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_CTRL
+ tristate "RPMSG control interface"
+ depends on RPMSG
+ help
+ Say Y here to enable the support of the /dev/rpmsg_ctrlX API. This API
+ allows user-space programs to create endpoints with specific service name,
+ source and destination addresses.
+
config RPMSG_NS
tristate "RPMSG name service announcement"
depends on RPMSG
diff --git a/drivers/rpmsg/Makefile b/drivers/rpmsg/Makefile
index 8d452656f0ee..58e3b382e316 100644
--- a/drivers/rpmsg/Makefile
+++ b/drivers/rpmsg/Makefile
@@ -1,6 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_RPMSG) += rpmsg_core.o
obj-$(CONFIG_RPMSG_CHAR) += rpmsg_char.o
+obj-$(CONFIG_RPMSG_CTRL) += rpmsg_ctrl.o
obj-$(CONFIG_RPMSG_NS) += rpmsg_ns.o
obj-$(CONFIG_RPMSG_MTK_SCP) += mtk_rpmsg.o
qcom_glink-objs := qcom_glink_native.o qcom_glink_ssr.o
diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
index 941c5c54dd72..fbe10d527c5c 100644
--- a/drivers/rpmsg/rpmsg_char.c
+++ b/drivers/rpmsg/rpmsg_char.c
@@ -25,33 +25,15 @@

#include "rpmsg_char.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
@@ -408,151 +390,11 @@ int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent
}
EXPORT_SYMBOL(rpmsg_chrdev_eptdev_create);

-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_chrdev_eptdev_create(ctrldev->rpdev, &ctrldev->dev, 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,
- .compat_ioctl = compat_ptr_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_add 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_chrdev_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_chrdev_init(void)
{
int ret;

- ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg");
+ ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg_char");
if (ret < 0) {
pr_err("rpmsg: failed to allocate char dev region\n");
return ret;
@@ -565,20 +407,12 @@ static int rpmsg_chrdev_init(void)
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;
+ return 0;
}
postcore_initcall(rpmsg_chrdev_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);
}
diff --git a/drivers/rpmsg/rpmsg_char.h b/drivers/rpmsg/rpmsg_char.h
index 22573b60e008..c328eb250b87 100644
--- a/drivers/rpmsg/rpmsg_char.h
+++ b/drivers/rpmsg/rpmsg_char.h
@@ -6,6 +6,8 @@
#ifndef __RPMSG_CHRDEV_H__
#define __RPMSG_CHRDEV_H__

+#define RPMSG_DEV_MAX (MINORMASK + 1)
+
#if IS_REACHABLE(CONFIG_RPMSG_CHAR)
/**
* rpmsg_chrdev_eptdev_create() - register char device based on an endpoint
diff --git a/drivers/rpmsg/rpmsg_ctrl.c b/drivers/rpmsg/rpmsg_ctrl.c
new file mode 100644
index 000000000000..87a1746367eb
--- /dev/null
+++ b/drivers/rpmsg/rpmsg_ctrl.c
@@ -0,0 +1,215 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021, STMicroelectronics
+ * Copyright (c) 2016, Linaro Ltd.
+ * Copyright (c) 2012, Michal Simek <monstr@xxxxxxxxx>
+ * 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.
+ */
+#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/rpmsg.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <uapi/linux/rpmsg.h>
+
+#include "rpmsg_char.h"
+
+static dev_t rpmsg_major;
+
+static DEFINE_IDA(rpmsg_ctrl_ida);
+static DEFINE_IDA(rpmsg_minor_ida);
+
+#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;
+};
+
+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_chrdev_eptdev_create(ctrldev->rpdev, &ctrldev->dev, 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,
+ .compat_ioctl = compat_ptr_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_ctrldev_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;
+
+ 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_add 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_ctrldev_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_chrdev_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_ctrldev_driver = {
+ .probe = rpmsg_ctrldev_probe,
+ .remove = rpmsg_ctrldev_remove,
+ .drv = {
+ .name = "rpmsg_chrdev",
+ },
+};
+
+static int rpmsg_ctrldev_init(void)
+{
+ int ret;
+
+ ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg_ctrl");
+ if (ret < 0) {
+ pr_err("rpmsg: failed to allocate char dev region\n");
+ return ret;
+ }
+
+ ret = register_rpmsg_driver(&rpmsg_ctrldev_driver);
+ if (ret < 0) {
+ pr_err("rpmsg ctrl: failed to register rpmsg driver\n");
+ unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
+ }
+
+ return ret;
+}
+postcore_initcall(rpmsg_ctrldev_init);
+
+static void rpmsg_ctrldev_exit(void)
+{
+ unregister_rpmsg_driver(&rpmsg_ctrldev_driver);
+ unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
+}
+module_exit(rpmsg_ctrldev_exit);
+
+MODULE_DESCRIPTION("rpmsg control interface");
+MODULE_ALIAS("rpmsg:" KBUILD_MODNAME);
+MODULE_LICENSE("GPL v2");
--
2.17.1