1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (c) 2016, Linaro Ltd.
4 * Copyright (c) 2012, Michal Simek <monstr@monstr.eu>
5 * Copyright (c) 2012, PetaLogix
6 * Copyright (c) 2011, Texas Instruments, Inc.
7 * Copyright (c) 2011, Google, Inc.
9 * Based on rpmsg performance statistics driver by Michal Simek, which in turn
10 * was based on TI & Google OMX rpmsg driver.
12 #include <linux/cdev.h>
13 #include <linux/device.h>
15 #include <linux/idr.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/poll.h>
19 #include <linux/rpmsg.h>
20 #include <linux/skbuff.h>
21 #include <linux/slab.h>
22 #include <linux/uaccess.h>
23 #include <uapi/linux/rpmsg.h>
25 #include "rpmsg_internal.h"
27 #define RPMSG_DEV_MAX (MINORMASK + 1)
29 static dev_t rpmsg_major;
30 static struct class *rpmsg_class;
32 static DEFINE_IDA(rpmsg_ctrl_ida);
33 static DEFINE_IDA(rpmsg_ept_ida);
34 static DEFINE_IDA(rpmsg_minor_ida);
36 #define dev_to_eptdev(dev) container_of(dev, struct rpmsg_eptdev, dev)
37 #define cdev_to_eptdev(i_cdev) container_of(i_cdev, struct rpmsg_eptdev, cdev)
39 #define dev_to_ctrldev(dev) container_of(dev, struct rpmsg_ctrldev, dev)
40 #define cdev_to_ctrldev(i_cdev) container_of(i_cdev, struct rpmsg_ctrldev, cdev)
43 * struct rpmsg_ctrldev - control device for instantiating endpoint devices
44 * @rpdev: underlaying rpmsg device
45 * @cdev: cdev for the ctrl device
46 * @dev: device for the ctrl device
48 struct rpmsg_ctrldev {
49 struct rpmsg_device *rpdev;
55 * struct rpmsg_eptdev - endpoint device context
56 * @dev: endpoint device
57 * @cdev: cdev for the endpoint device
58 * @rpdev: underlaying rpmsg device
59 * @chinfo: info used to open the endpoint
60 * @ept_lock: synchronization of @ept modifications
61 * @ept: rpmsg endpoint reference, when open
62 * @queue_lock: synchronization of @queue operations
63 * @queue: incoming message queue
64 * @readq: wait object for incoming queue
70 struct rpmsg_device *rpdev;
71 struct rpmsg_channel_info chinfo;
73 struct mutex ept_lock;
74 struct rpmsg_endpoint *ept;
76 spinlock_t queue_lock;
77 struct sk_buff_head queue;
78 wait_queue_head_t readq;
81 static int rpmsg_eptdev_destroy(struct device *dev, void *data)
83 struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev);
85 mutex_lock(&eptdev->ept_lock);
87 rpmsg_destroy_ept(eptdev->ept);
90 mutex_unlock(&eptdev->ept_lock);
92 /* wake up any blocked readers */
93 wake_up_interruptible(&eptdev->readq);
95 cdev_device_del(&eptdev->cdev, &eptdev->dev);
96 put_device(&eptdev->dev);
101 static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len,
102 void *priv, u32 addr)
104 struct rpmsg_eptdev *eptdev = priv;
107 skb = alloc_skb(len, GFP_ATOMIC);
111 skb_put_data(skb, buf, len);
113 spin_lock(&eptdev->queue_lock);
114 skb_queue_tail(&eptdev->queue, skb);
115 spin_unlock(&eptdev->queue_lock);
117 /* wake up any blocking processes, waiting for new data */
118 wake_up_interruptible(&eptdev->readq);
123 static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)
125 struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev);
126 struct rpmsg_endpoint *ept;
127 struct rpmsg_device *rpdev = eptdev->rpdev;
128 struct device *dev = &eptdev->dev;
135 ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo);
137 dev_err(dev, "failed to open %s\n", eptdev->chinfo.name);
143 filp->private_data = eptdev;
148 static int rpmsg_eptdev_release(struct inode *inode, struct file *filp)
150 struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev);
151 struct device *dev = &eptdev->dev;
153 /* Close the endpoint, if it's not already destroyed by the parent */
154 mutex_lock(&eptdev->ept_lock);
156 rpmsg_destroy_ept(eptdev->ept);
159 mutex_unlock(&eptdev->ept_lock);
161 /* Discard all SKBs */
162 skb_queue_purge(&eptdev->queue);
169 static ssize_t rpmsg_eptdev_read_iter(struct kiocb *iocb, struct iov_iter *to)
171 struct file *filp = iocb->ki_filp;
172 struct rpmsg_eptdev *eptdev = filp->private_data;
180 spin_lock_irqsave(&eptdev->queue_lock, flags);
182 /* Wait for data in the queue */
183 if (skb_queue_empty(&eptdev->queue)) {
184 spin_unlock_irqrestore(&eptdev->queue_lock, flags);
186 if (filp->f_flags & O_NONBLOCK)
189 /* Wait until we get data or the endpoint goes away */
190 if (wait_event_interruptible(eptdev->readq,
191 !skb_queue_empty(&eptdev->queue) ||
195 /* We lost the endpoint while waiting */
199 spin_lock_irqsave(&eptdev->queue_lock, flags);
202 skb = skb_dequeue(&eptdev->queue);
203 spin_unlock_irqrestore(&eptdev->queue_lock, flags);
207 use = min_t(size_t, iov_iter_count(to), skb->len);
208 if (copy_to_iter(skb->data, use, to) != use)
216 static ssize_t rpmsg_eptdev_write_iter(struct kiocb *iocb,
217 struct iov_iter *from)
219 struct file *filp = iocb->ki_filp;
220 struct rpmsg_eptdev *eptdev = filp->private_data;
221 size_t len = iov_iter_count(from);
225 kbuf = kzalloc(len, GFP_KERNEL);
229 if (!copy_from_iter_full(kbuf, len, from)) {
234 if (mutex_lock_interruptible(&eptdev->ept_lock)) {
244 if (filp->f_flags & O_NONBLOCK)
245 ret = rpmsg_trysendto(eptdev->ept, kbuf, len, eptdev->chinfo.dst);
247 ret = rpmsg_sendto(eptdev->ept, kbuf, len, eptdev->chinfo.dst);
250 mutex_unlock(&eptdev->ept_lock);
254 return ret < 0 ? ret : len;
257 static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait)
259 struct rpmsg_eptdev *eptdev = filp->private_data;
265 poll_wait(filp, &eptdev->readq, wait);
267 if (!skb_queue_empty(&eptdev->queue))
268 mask |= EPOLLIN | EPOLLRDNORM;
270 mask |= rpmsg_poll(eptdev->ept, filp, wait);
275 static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd,
278 struct rpmsg_eptdev *eptdev = fp->private_data;
280 if (cmd != RPMSG_DESTROY_EPT_IOCTL)
283 return rpmsg_eptdev_destroy(&eptdev->dev, NULL);
286 static const struct file_operations rpmsg_eptdev_fops = {
287 .owner = THIS_MODULE,
288 .open = rpmsg_eptdev_open,
289 .release = rpmsg_eptdev_release,
290 .read_iter = rpmsg_eptdev_read_iter,
291 .write_iter = rpmsg_eptdev_write_iter,
292 .poll = rpmsg_eptdev_poll,
293 .unlocked_ioctl = rpmsg_eptdev_ioctl,
294 .compat_ioctl = compat_ptr_ioctl,
297 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
300 struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);
302 return sprintf(buf, "%s\n", eptdev->chinfo.name);
304 static DEVICE_ATTR_RO(name);
306 static ssize_t src_show(struct device *dev, struct device_attribute *attr,
309 struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);
311 return sprintf(buf, "%d\n", eptdev->chinfo.src);
313 static DEVICE_ATTR_RO(src);
315 static ssize_t dst_show(struct device *dev, struct device_attribute *attr,
318 struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);
320 return sprintf(buf, "%d\n", eptdev->chinfo.dst);
322 static DEVICE_ATTR_RO(dst);
324 static struct attribute *rpmsg_eptdev_attrs[] = {
330 ATTRIBUTE_GROUPS(rpmsg_eptdev);
332 static void rpmsg_eptdev_release_device(struct device *dev)
334 struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev);
336 ida_simple_remove(&rpmsg_ept_ida, dev->id);
337 ida_simple_remove(&rpmsg_minor_ida, MINOR(eptdev->dev.devt));
341 static int rpmsg_eptdev_create(struct rpmsg_ctrldev *ctrldev,
342 struct rpmsg_channel_info chinfo)
344 struct rpmsg_device *rpdev = ctrldev->rpdev;
345 struct rpmsg_eptdev *eptdev;
349 eptdev = kzalloc(sizeof(*eptdev), GFP_KERNEL);
354 eptdev->rpdev = rpdev;
355 eptdev->chinfo = chinfo;
357 mutex_init(&eptdev->ept_lock);
358 spin_lock_init(&eptdev->queue_lock);
359 skb_queue_head_init(&eptdev->queue);
360 init_waitqueue_head(&eptdev->readq);
362 device_initialize(dev);
363 dev->class = rpmsg_class;
364 dev->parent = &ctrldev->dev;
365 dev->groups = rpmsg_eptdev_groups;
366 dev_set_drvdata(dev, eptdev);
368 cdev_init(&eptdev->cdev, &rpmsg_eptdev_fops);
369 eptdev->cdev.owner = THIS_MODULE;
371 ret = ida_simple_get(&rpmsg_minor_ida, 0, RPMSG_DEV_MAX, GFP_KERNEL);
374 dev->devt = MKDEV(MAJOR(rpmsg_major), ret);
376 ret = ida_simple_get(&rpmsg_ept_ida, 0, 0, GFP_KERNEL);
380 dev_set_name(dev, "rpmsg%d", ret);
382 ret = cdev_device_add(&eptdev->cdev, &eptdev->dev);
386 /* We can now rely on the release function for cleanup */
387 dev->release = rpmsg_eptdev_release_device;
392 ida_simple_remove(&rpmsg_ept_ida, dev->id);
394 ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt));
402 static int rpmsg_ctrldev_open(struct inode *inode, struct file *filp)
404 struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev);
406 get_device(&ctrldev->dev);
407 filp->private_data = ctrldev;
412 static int rpmsg_ctrldev_release(struct inode *inode, struct file *filp)
414 struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev);
416 put_device(&ctrldev->dev);
421 static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd,
424 struct rpmsg_ctrldev *ctrldev = fp->private_data;
425 void __user *argp = (void __user *)arg;
426 struct rpmsg_endpoint_info eptinfo;
427 struct rpmsg_channel_info chinfo;
429 if (cmd != RPMSG_CREATE_EPT_IOCTL)
432 if (copy_from_user(&eptinfo, argp, sizeof(eptinfo)))
435 memcpy(chinfo.name, eptinfo.name, RPMSG_NAME_SIZE);
436 chinfo.name[RPMSG_NAME_SIZE-1] = '\0';
437 chinfo.src = eptinfo.src;
438 chinfo.dst = eptinfo.dst;
440 return rpmsg_eptdev_create(ctrldev, chinfo);
443 static const struct file_operations rpmsg_ctrldev_fops = {
444 .owner = THIS_MODULE,
445 .open = rpmsg_ctrldev_open,
446 .release = rpmsg_ctrldev_release,
447 .unlocked_ioctl = rpmsg_ctrldev_ioctl,
448 .compat_ioctl = compat_ptr_ioctl,
451 static void rpmsg_ctrldev_release_device(struct device *dev)
453 struct rpmsg_ctrldev *ctrldev = dev_to_ctrldev(dev);
455 ida_simple_remove(&rpmsg_ctrl_ida, dev->id);
456 ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt));
460 static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev)
462 struct rpmsg_ctrldev *ctrldev;
466 ctrldev = kzalloc(sizeof(*ctrldev), GFP_KERNEL);
470 ctrldev->rpdev = rpdev;
473 device_initialize(dev);
474 dev->parent = &rpdev->dev;
475 dev->class = rpmsg_class;
477 cdev_init(&ctrldev->cdev, &rpmsg_ctrldev_fops);
478 ctrldev->cdev.owner = THIS_MODULE;
480 ret = ida_simple_get(&rpmsg_minor_ida, 0, RPMSG_DEV_MAX, GFP_KERNEL);
483 dev->devt = MKDEV(MAJOR(rpmsg_major), ret);
485 ret = ida_simple_get(&rpmsg_ctrl_ida, 0, 0, GFP_KERNEL);
489 dev_set_name(&ctrldev->dev, "rpmsg_ctrl%d", ret);
491 ret = cdev_device_add(&ctrldev->cdev, &ctrldev->dev);
495 /* We can now rely on the release function for cleanup */
496 dev->release = rpmsg_ctrldev_release_device;
498 dev_set_drvdata(&rpdev->dev, ctrldev);
503 ida_simple_remove(&rpmsg_ctrl_ida, dev->id);
505 ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt));
513 static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev)
515 struct rpmsg_ctrldev *ctrldev = dev_get_drvdata(&rpdev->dev);
518 /* Destroy all endpoints */
519 ret = device_for_each_child(&ctrldev->dev, NULL, rpmsg_eptdev_destroy);
521 dev_warn(&rpdev->dev, "failed to nuke endpoints: %d\n", ret);
523 cdev_device_del(&ctrldev->cdev, &ctrldev->dev);
524 put_device(&ctrldev->dev);
527 static struct rpmsg_driver rpmsg_chrdev_driver = {
528 .probe = rpmsg_chrdev_probe,
529 .remove = rpmsg_chrdev_remove,
531 .name = "rpmsg_chrdev",
535 static int rpmsg_chrdev_init(void)
539 ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg");
541 pr_err("rpmsg: failed to allocate char dev region\n");
545 rpmsg_class = class_create(THIS_MODULE, "rpmsg");
546 if (IS_ERR(rpmsg_class)) {
547 pr_err("failed to create rpmsg class\n");
548 unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
549 return PTR_ERR(rpmsg_class);
552 ret = register_rpmsg_driver(&rpmsg_chrdev_driver);
554 pr_err("rpmsgchr: failed to register rpmsg driver\n");
555 class_destroy(rpmsg_class);
556 unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
561 postcore_initcall(rpmsg_chrdev_init);
563 static void rpmsg_chrdev_exit(void)
565 unregister_rpmsg_driver(&rpmsg_chrdev_driver);
566 class_destroy(rpmsg_class);
567 unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
569 module_exit(rpmsg_chrdev_exit);
571 MODULE_ALIAS("rpmsg:rpmsg_chrdev");
572 MODULE_LICENSE("GPL v2");