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Diffstat (limited to 'drivers/rpmsg/rpmsg_ctrl.c')
-rw-r--r--drivers/rpmsg/rpmsg_ctrl.c245
1 files changed, 245 insertions, 0 deletions
diff --git a/drivers/rpmsg/rpmsg_ctrl.c b/drivers/rpmsg/rpmsg_ctrl.c
new file mode 100644
index 0000000000..4332538356
--- /dev/null
+++ b/drivers/rpmsg/rpmsg_ctrl.c
@@ -0,0 +1,245 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022, STMicroelectronics
+ * 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#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"
+#include "rpmsg_internal.h"
+
+#define RPMSG_DEV_MAX (MINORMASK + 1)
+
+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
+ * @ctrl_lock: serialize the ioctrls.
+ */
+struct rpmsg_ctrldev {
+ struct rpmsg_device *rpdev;
+ struct cdev cdev;
+ struct device dev;
+ struct mutex ctrl_lock;
+};
+
+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;
+ struct rpmsg_device *rpdev;
+ int ret = 0;
+
+ 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;
+
+ mutex_lock(&ctrldev->ctrl_lock);
+ switch (cmd) {
+ case RPMSG_CREATE_EPT_IOCTL:
+ ret = rpmsg_chrdev_eptdev_create(ctrldev->rpdev, &ctrldev->dev, chinfo);
+ break;
+
+ case RPMSG_CREATE_DEV_IOCTL:
+ rpdev = rpmsg_create_channel(ctrldev->rpdev, &chinfo);
+ if (!rpdev) {
+ dev_err(&ctrldev->dev, "failed to create %s channel\n", chinfo.name);
+ ret = -ENXIO;
+ }
+ break;
+
+ case RPMSG_RELEASE_DEV_IOCTL:
+ ret = rpmsg_release_channel(ctrldev->rpdev, &chinfo);
+ if (ret)
+ dev_err(&ctrldev->dev, "failed to release %s channel (%d)\n",
+ chinfo.name, ret);
+ break;
+
+ default:
+ ret = -EINVAL;
+ }
+ mutex_unlock(&ctrldev->ctrl_lock);
+
+ return ret;
+};
+
+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));
+ 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;
+ dev->class = rpmsg_class;
+
+ mutex_init(&ctrldev->ctrl_lock);
+ 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_device_add(&ctrldev->cdev, &ctrldev->dev);
+ if (ret)
+ goto free_ctrl_ida;
+
+ /* We can now rely on the release function for cleanup */
+ dev->release = rpmsg_ctrldev_release_device;
+
+ 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;
+
+ mutex_lock(&ctrldev->ctrl_lock);
+ /* 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);
+ mutex_unlock(&ctrldev->ctrl_lock);
+
+ cdev_device_del(&ctrldev->cdev, &ctrldev->dev);
+ put_device(&ctrldev->dev);
+}
+
+static struct rpmsg_driver rpmsg_ctrldev_driver = {
+ .probe = rpmsg_ctrldev_probe,
+ .remove = rpmsg_ctrldev_remove,
+ .drv = {
+ .name = "rpmsg_ctrl",
+ },
+};
+
+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("failed to allocate char dev region\n");
+ return ret;
+ }
+
+ ret = register_rpmsg_driver(&rpmsg_ctrldev_driver);
+ if (ret < 0) {
+ pr_err("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");