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;
130 mutex_lock(&eptdev->ept_lock);
132 mutex_unlock(&eptdev->ept_lock);
138 ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo);
140 dev_err(dev, "failed to open %s\n", eptdev->chinfo.name);
142 mutex_unlock(&eptdev->ept_lock);
147 filp->private_data = eptdev;
148 mutex_unlock(&eptdev->ept_lock);
153 static int rpmsg_eptdev_release(struct inode *inode, struct file *filp)
155 struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev);
156 struct device *dev = &eptdev->dev;
158 /* Close the endpoint, if it's not already destroyed by the parent */
159 mutex_lock(&eptdev->ept_lock);
161 rpmsg_destroy_ept(eptdev->ept);
164 mutex_unlock(&eptdev->ept_lock);
166 /* Discard all SKBs */
167 skb_queue_purge(&eptdev->queue);
174 static ssize_t rpmsg_eptdev_read_iter(struct kiocb *iocb, struct iov_iter *to)
176 struct file *filp = iocb->ki_filp;
177 struct rpmsg_eptdev *eptdev = filp->private_data;
185 spin_lock_irqsave(&eptdev->queue_lock, flags);
187 /* Wait for data in the queue */
188 if (skb_queue_empty(&eptdev->queue)) {
189 spin_unlock_irqrestore(&eptdev->queue_lock, flags);
191 if (filp->f_flags & O_NONBLOCK)
194 /* Wait until we get data or the endpoint goes away */
195 if (wait_event_interruptible(eptdev->readq,
196 !skb_queue_empty(&eptdev->queue) ||
200 /* We lost the endpoint while waiting */
204 spin_lock_irqsave(&eptdev->queue_lock, flags);
207 skb = skb_dequeue(&eptdev->queue);
208 spin_unlock_irqrestore(&eptdev->queue_lock, flags);
212 use = min_t(size_t, iov_iter_count(to), skb->len);
213 if (copy_to_iter(skb->data, use, to) != use)
221 static ssize_t rpmsg_eptdev_write_iter(struct kiocb *iocb,
222 struct iov_iter *from)
224 struct file *filp = iocb->ki_filp;
225 struct rpmsg_eptdev *eptdev = filp->private_data;
226 size_t len = iov_iter_count(from);
230 kbuf = kzalloc(len, GFP_KERNEL);
234 if (!copy_from_iter_full(kbuf, len, from)) {
239 if (mutex_lock_interruptible(&eptdev->ept_lock)) {
249 if (filp->f_flags & O_NONBLOCK)
250 ret = rpmsg_trysendto(eptdev->ept, kbuf, len, eptdev->chinfo.dst);
252 ret = rpmsg_sendto(eptdev->ept, kbuf, len, eptdev->chinfo.dst);
255 mutex_unlock(&eptdev->ept_lock);
259 return ret < 0 ? ret : len;
262 static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait)
264 struct rpmsg_eptdev *eptdev = filp->private_data;
270 poll_wait(filp, &eptdev->readq, wait);
272 if (!skb_queue_empty(&eptdev->queue))
273 mask |= EPOLLIN | EPOLLRDNORM;
275 mask |= rpmsg_poll(eptdev->ept, filp, wait);
280 static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd,
283 struct rpmsg_eptdev *eptdev = fp->private_data;
285 if (cmd != RPMSG_DESTROY_EPT_IOCTL)
288 return rpmsg_eptdev_destroy(&eptdev->dev, NULL);
291 static const struct file_operations rpmsg_eptdev_fops = {
292 .owner = THIS_MODULE,
293 .open = rpmsg_eptdev_open,
294 .release = rpmsg_eptdev_release,
295 .read_iter = rpmsg_eptdev_read_iter,
296 .write_iter = rpmsg_eptdev_write_iter,
297 .poll = rpmsg_eptdev_poll,
298 .unlocked_ioctl = rpmsg_eptdev_ioctl,
299 .compat_ioctl = compat_ptr_ioctl,
302 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
305 struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);
307 return sprintf(buf, "%s\n", eptdev->chinfo.name);
309 static DEVICE_ATTR_RO(name);
311 static ssize_t src_show(struct device *dev, struct device_attribute *attr,
314 struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);
316 return sprintf(buf, "%d\n", eptdev->chinfo.src);
318 static DEVICE_ATTR_RO(src);
320 static ssize_t dst_show(struct device *dev, struct device_attribute *attr,
323 struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);
325 return sprintf(buf, "%d\n", eptdev->chinfo.dst);
327 static DEVICE_ATTR_RO(dst);
329 static struct attribute *rpmsg_eptdev_attrs[] = {
335 ATTRIBUTE_GROUPS(rpmsg_eptdev);
337 static void rpmsg_eptdev_release_device(struct device *dev)
339 struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev);
341 ida_simple_remove(&rpmsg_ept_ida, dev->id);
342 ida_simple_remove(&rpmsg_minor_ida, MINOR(eptdev->dev.devt));
346 static int rpmsg_eptdev_create(struct rpmsg_ctrldev *ctrldev,
347 struct rpmsg_channel_info chinfo)
349 struct rpmsg_device *rpdev = ctrldev->rpdev;
350 struct rpmsg_eptdev *eptdev;
354 eptdev = kzalloc(sizeof(*eptdev), GFP_KERNEL);
359 eptdev->rpdev = rpdev;
360 eptdev->chinfo = chinfo;
362 mutex_init(&eptdev->ept_lock);
363 spin_lock_init(&eptdev->queue_lock);
364 skb_queue_head_init(&eptdev->queue);
365 init_waitqueue_head(&eptdev->readq);
367 device_initialize(dev);
368 dev->class = rpmsg_class;
369 dev->parent = &ctrldev->dev;
370 dev->groups = rpmsg_eptdev_groups;
371 dev_set_drvdata(dev, eptdev);
373 cdev_init(&eptdev->cdev, &rpmsg_eptdev_fops);
374 eptdev->cdev.owner = THIS_MODULE;
376 ret = ida_simple_get(&rpmsg_minor_ida, 0, RPMSG_DEV_MAX, GFP_KERNEL);
379 dev->devt = MKDEV(MAJOR(rpmsg_major), ret);
381 ret = ida_simple_get(&rpmsg_ept_ida, 0, 0, GFP_KERNEL);
385 dev_set_name(dev, "rpmsg%d", ret);
387 ret = cdev_device_add(&eptdev->cdev, &eptdev->dev);
391 /* We can now rely on the release function for cleanup */
392 dev->release = rpmsg_eptdev_release_device;
397 ida_simple_remove(&rpmsg_ept_ida, dev->id);
399 ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt));
407 static int rpmsg_ctrldev_open(struct inode *inode, struct file *filp)
409 struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev);
411 get_device(&ctrldev->dev);
412 filp->private_data = ctrldev;
417 static int rpmsg_ctrldev_release(struct inode *inode, struct file *filp)
419 struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev);
421 put_device(&ctrldev->dev);
426 static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd,
429 struct rpmsg_ctrldev *ctrldev = fp->private_data;
430 void __user *argp = (void __user *)arg;
431 struct rpmsg_endpoint_info eptinfo;
432 struct rpmsg_channel_info chinfo;
434 if (cmd != RPMSG_CREATE_EPT_IOCTL)
437 if (copy_from_user(&eptinfo, argp, sizeof(eptinfo)))
440 memcpy(chinfo.name, eptinfo.name, RPMSG_NAME_SIZE);
441 chinfo.name[RPMSG_NAME_SIZE-1] = '\0';
442 chinfo.src = eptinfo.src;
443 chinfo.dst = eptinfo.dst;
445 return rpmsg_eptdev_create(ctrldev, chinfo);
448 static const struct file_operations rpmsg_ctrldev_fops = {
449 .owner = THIS_MODULE,
450 .open = rpmsg_ctrldev_open,
451 .release = rpmsg_ctrldev_release,
452 .unlocked_ioctl = rpmsg_ctrldev_ioctl,
453 .compat_ioctl = compat_ptr_ioctl,
456 static void rpmsg_ctrldev_release_device(struct device *dev)
458 struct rpmsg_ctrldev *ctrldev = dev_to_ctrldev(dev);
460 ida_simple_remove(&rpmsg_ctrl_ida, dev->id);
461 ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt));
465 static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev)
467 struct rpmsg_ctrldev *ctrldev;
471 ctrldev = kzalloc(sizeof(*ctrldev), GFP_KERNEL);
475 ctrldev->rpdev = rpdev;
478 device_initialize(dev);
479 dev->parent = &rpdev->dev;
480 dev->class = rpmsg_class;
482 cdev_init(&ctrldev->cdev, &rpmsg_ctrldev_fops);
483 ctrldev->cdev.owner = THIS_MODULE;
485 ret = ida_simple_get(&rpmsg_minor_ida, 0, RPMSG_DEV_MAX, GFP_KERNEL);
488 dev->devt = MKDEV(MAJOR(rpmsg_major), ret);
490 ret = ida_simple_get(&rpmsg_ctrl_ida, 0, 0, GFP_KERNEL);
494 dev_set_name(&ctrldev->dev, "rpmsg_ctrl%d", ret);
496 ret = cdev_device_add(&ctrldev->cdev, &ctrldev->dev);
500 /* We can now rely on the release function for cleanup */
501 dev->release = rpmsg_ctrldev_release_device;
503 dev_set_drvdata(&rpdev->dev, ctrldev);
508 ida_simple_remove(&rpmsg_ctrl_ida, dev->id);
510 ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt));
518 static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev)
520 struct rpmsg_ctrldev *ctrldev = dev_get_drvdata(&rpdev->dev);
523 /* Destroy all endpoints */
524 ret = device_for_each_child(&ctrldev->dev, NULL, rpmsg_eptdev_destroy);
526 dev_warn(&rpdev->dev, "failed to nuke endpoints: %d\n", ret);
528 cdev_device_del(&ctrldev->cdev, &ctrldev->dev);
529 put_device(&ctrldev->dev);
532 static struct rpmsg_driver rpmsg_chrdev_driver = {
533 .probe = rpmsg_chrdev_probe,
534 .remove = rpmsg_chrdev_remove,
536 .name = "rpmsg_chrdev",
540 static int rpmsg_chrdev_init(void)
544 ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg");
546 pr_err("rpmsg: failed to allocate char dev region\n");
550 rpmsg_class = class_create(THIS_MODULE, "rpmsg");
551 if (IS_ERR(rpmsg_class)) {
552 pr_err("failed to create rpmsg class\n");
553 unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
554 return PTR_ERR(rpmsg_class);
557 ret = register_rpmsg_driver(&rpmsg_chrdev_driver);
559 pr_err("rpmsgchr: failed to register rpmsg driver\n");
560 class_destroy(rpmsg_class);
561 unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
566 postcore_initcall(rpmsg_chrdev_init);
568 static void rpmsg_chrdev_exit(void)
570 unregister_rpmsg_driver(&rpmsg_chrdev_driver);
571 class_destroy(rpmsg_class);
572 unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
574 module_exit(rpmsg_chrdev_exit);
576 MODULE_ALIAS("rpmsg:rpmsg_chrdev");
577 MODULE_LICENSE("GPL v2");