| 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * Copyright (C) 2022, STMicroelectronics |
| 4 | * Copyright (c) 2016, Linaro Ltd. |
| 5 | * Copyright (c) 2012, Michal Simek <monstr@monstr.eu> |
| 6 | * Copyright (c) 2012, PetaLogix |
| 7 | * Copyright (c) 2011, Texas Instruments, Inc. |
| 8 | * Copyright (c) 2011, Google, Inc. |
| 9 | * |
| 10 | * Based on rpmsg performance statistics driver by Michal Simek, which in turn |
| 11 | * was based on TI & Google OMX rpmsg driver. |
| 12 | */ |
| 13 | |
| 14 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 15 | |
| 16 | #include <linux/cdev.h> |
| 17 | #include <linux/device.h> |
| 18 | #include <linux/fs.h> |
| 19 | #include <linux/idr.h> |
| 20 | #include <linux/kernel.h> |
| 21 | #include <linux/module.h> |
| 22 | #include <linux/poll.h> |
| 23 | #include <linux/rpmsg.h> |
| 24 | #include <linux/skbuff.h> |
| 25 | #include <linux/slab.h> |
| 26 | #include <linux/uaccess.h> |
| 27 | #include <uapi/linux/rpmsg.h> |
| 28 | |
| 29 | #include "rpmsg_char.h" |
| 30 | #include "rpmsg_internal.h" |
| 31 | |
| 32 | #define RPMSG_DEV_MAX (MINORMASK + 1) |
| 33 | |
| 34 | static dev_t rpmsg_major; |
| 35 | |
| 36 | static DEFINE_IDA(rpmsg_ept_ida); |
| 37 | static DEFINE_IDA(rpmsg_minor_ida); |
| 38 | |
| 39 | #define dev_to_eptdev(dev) container_of(dev, struct rpmsg_eptdev, dev) |
| 40 | #define cdev_to_eptdev(i_cdev) container_of(i_cdev, struct rpmsg_eptdev, cdev) |
| 41 | |
| 42 | /** |
| 43 | * struct rpmsg_eptdev - endpoint device context |
| 44 | * @dev: endpoint device |
| 45 | * @cdev: cdev for the endpoint device |
| 46 | * @rpdev: underlaying rpmsg device |
| 47 | * @chinfo: info used to open the endpoint |
| 48 | * @ept_lock: synchronization of @ept modifications |
| 49 | * @ept: rpmsg endpoint reference, when open |
| 50 | * @queue_lock: synchronization of @queue operations |
| 51 | * @queue: incoming message queue |
| 52 | * @readq: wait object for incoming queue |
| 53 | * @default_ept: set to channel default endpoint if the default endpoint should be re-used |
| 54 | * on device open to prevent endpoint address update. |
| 55 | * @remote_flow_restricted: to indicate if the remote has requested for flow to be limited |
| 56 | * @remote_flow_updated: to indicate if the flow control has been requested |
| 57 | */ |
| 58 | struct rpmsg_eptdev { |
| 59 | struct device dev; |
| 60 | struct cdev cdev; |
| 61 | |
| 62 | struct rpmsg_device *rpdev; |
| 63 | struct rpmsg_channel_info chinfo; |
| 64 | |
| 65 | struct mutex ept_lock; |
| 66 | struct rpmsg_endpoint *ept; |
| 67 | struct rpmsg_endpoint *default_ept; |
| 68 | |
| 69 | spinlock_t queue_lock; |
| 70 | struct sk_buff_head queue; |
| 71 | wait_queue_head_t readq; |
| 72 | |
| 73 | bool remote_flow_restricted; |
| 74 | bool remote_flow_updated; |
| 75 | }; |
| 76 | |
| 77 | int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data) |
| 78 | { |
| 79 | struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev); |
| 80 | |
| 81 | mutex_lock(&eptdev->ept_lock); |
| 82 | eptdev->rpdev = NULL; |
| 83 | if (eptdev->ept) { |
| 84 | /* The default endpoint is released by the rpmsg core */ |
| 85 | if (!eptdev->default_ept) |
| 86 | rpmsg_destroy_ept(eptdev->ept); |
| 87 | eptdev->ept = NULL; |
| 88 | } |
| 89 | mutex_unlock(&eptdev->ept_lock); |
| 90 | |
| 91 | /* wake up any blocked readers */ |
| 92 | wake_up_interruptible(&eptdev->readq); |
| 93 | |
| 94 | cdev_device_del(&eptdev->cdev, &eptdev->dev); |
| 95 | put_device(&eptdev->dev); |
| 96 | |
| 97 | return 0; |
| 98 | } |
| 99 | EXPORT_SYMBOL(rpmsg_chrdev_eptdev_destroy); |
| 100 | |
| 101 | static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len, |
| 102 | void *priv, u32 addr) |
| 103 | { |
| 104 | struct rpmsg_eptdev *eptdev = priv; |
| 105 | struct sk_buff *skb; |
| 106 | |
| 107 | skb = alloc_skb(len, GFP_ATOMIC); |
| 108 | if (!skb) |
| 109 | return -ENOMEM; |
| 110 | |
| 111 | skb_put_data(skb, buf, len); |
| 112 | |
| 113 | spin_lock(&eptdev->queue_lock); |
| 114 | skb_queue_tail(&eptdev->queue, skb); |
| 115 | spin_unlock(&eptdev->queue_lock); |
| 116 | |
| 117 | /* wake up any blocking processes, waiting for new data */ |
| 118 | wake_up_interruptible(&eptdev->readq); |
| 119 | |
| 120 | return 0; |
| 121 | } |
| 122 | |
| 123 | static int rpmsg_ept_flow_cb(struct rpmsg_device *rpdev, void *priv, bool enable) |
| 124 | { |
| 125 | struct rpmsg_eptdev *eptdev = priv; |
| 126 | |
| 127 | eptdev->remote_flow_restricted = enable; |
| 128 | eptdev->remote_flow_updated = true; |
| 129 | |
| 130 | wake_up_interruptible(&eptdev->readq); |
| 131 | |
| 132 | return 0; |
| 133 | } |
| 134 | |
| 135 | static int rpmsg_eptdev_open(struct inode *inode, struct file *filp) |
| 136 | { |
| 137 | struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev); |
| 138 | struct rpmsg_endpoint *ept; |
| 139 | struct rpmsg_device *rpdev = eptdev->rpdev; |
| 140 | struct device *dev = &eptdev->dev; |
| 141 | |
| 142 | mutex_lock(&eptdev->ept_lock); |
| 143 | if (eptdev->ept) { |
| 144 | mutex_unlock(&eptdev->ept_lock); |
| 145 | return -EBUSY; |
| 146 | } |
| 147 | |
| 148 | if (!eptdev->rpdev) { |
| 149 | mutex_unlock(&eptdev->ept_lock); |
| 150 | return -ENETRESET; |
| 151 | } |
| 152 | |
| 153 | get_device(dev); |
| 154 | |
| 155 | /* |
| 156 | * If the default_ept is set, the rpmsg device default endpoint is used. |
| 157 | * Else a new endpoint is created on open that will be destroyed on release. |
| 158 | */ |
| 159 | if (eptdev->default_ept) |
| 160 | ept = eptdev->default_ept; |
| 161 | else |
| 162 | ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo); |
| 163 | |
| 164 | if (!ept) { |
| 165 | dev_err(dev, "failed to open %s\n", eptdev->chinfo.name); |
| 166 | put_device(dev); |
| 167 | mutex_unlock(&eptdev->ept_lock); |
| 168 | return -EINVAL; |
| 169 | } |
| 170 | |
| 171 | ept->flow_cb = rpmsg_ept_flow_cb; |
| 172 | eptdev->ept = ept; |
| 173 | filp->private_data = eptdev; |
| 174 | mutex_unlock(&eptdev->ept_lock); |
| 175 | |
| 176 | return 0; |
| 177 | } |
| 178 | |
| 179 | static int rpmsg_eptdev_release(struct inode *inode, struct file *filp) |
| 180 | { |
| 181 | struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev); |
| 182 | struct device *dev = &eptdev->dev; |
| 183 | |
| 184 | /* Close the endpoint, if it's not already destroyed by the parent */ |
| 185 | mutex_lock(&eptdev->ept_lock); |
| 186 | if (eptdev->ept) { |
| 187 | if (!eptdev->default_ept) |
| 188 | rpmsg_destroy_ept(eptdev->ept); |
| 189 | eptdev->ept = NULL; |
| 190 | } |
| 191 | mutex_unlock(&eptdev->ept_lock); |
| 192 | eptdev->remote_flow_updated = false; |
| 193 | |
| 194 | /* Discard all SKBs */ |
| 195 | skb_queue_purge(&eptdev->queue); |
| 196 | |
| 197 | put_device(dev); |
| 198 | |
| 199 | return 0; |
| 200 | } |
| 201 | |
| 202 | static ssize_t rpmsg_eptdev_read_iter(struct kiocb *iocb, struct iov_iter *to) |
| 203 | { |
| 204 | struct file *filp = iocb->ki_filp; |
| 205 | struct rpmsg_eptdev *eptdev = filp->private_data; |
| 206 | unsigned long flags; |
| 207 | struct sk_buff *skb; |
| 208 | int use; |
| 209 | |
| 210 | if (!eptdev->ept) |
| 211 | return -EPIPE; |
| 212 | |
| 213 | spin_lock_irqsave(&eptdev->queue_lock, flags); |
| 214 | |
| 215 | /* Wait for data in the queue */ |
| 216 | if (skb_queue_empty(&eptdev->queue)) { |
| 217 | spin_unlock_irqrestore(&eptdev->queue_lock, flags); |
| 218 | |
| 219 | if (filp->f_flags & O_NONBLOCK) |
| 220 | return -EAGAIN; |
| 221 | |
| 222 | /* Wait until we get data or the endpoint goes away */ |
| 223 | if (wait_event_interruptible(eptdev->readq, |
| 224 | !skb_queue_empty(&eptdev->queue) || |
| 225 | !eptdev->ept)) |
| 226 | return -ERESTARTSYS; |
| 227 | |
| 228 | /* We lost the endpoint while waiting */ |
| 229 | if (!eptdev->ept) |
| 230 | return -EPIPE; |
| 231 | |
| 232 | spin_lock_irqsave(&eptdev->queue_lock, flags); |
| 233 | } |
| 234 | |
| 235 | skb = skb_dequeue(&eptdev->queue); |
| 236 | spin_unlock_irqrestore(&eptdev->queue_lock, flags); |
| 237 | if (!skb) |
| 238 | return -EFAULT; |
| 239 | |
| 240 | use = min_t(size_t, iov_iter_count(to), skb->len); |
| 241 | if (copy_to_iter(skb->data, use, to) != use) |
| 242 | use = -EFAULT; |
| 243 | |
| 244 | kfree_skb(skb); |
| 245 | |
| 246 | return use; |
| 247 | } |
| 248 | |
| 249 | static ssize_t rpmsg_eptdev_write_iter(struct kiocb *iocb, |
| 250 | struct iov_iter *from) |
| 251 | { |
| 252 | struct file *filp = iocb->ki_filp; |
| 253 | struct rpmsg_eptdev *eptdev = filp->private_data; |
| 254 | size_t len = iov_iter_count(from); |
| 255 | void *kbuf; |
| 256 | int ret; |
| 257 | |
| 258 | kbuf = kzalloc(len, GFP_KERNEL); |
| 259 | if (!kbuf) |
| 260 | return -ENOMEM; |
| 261 | |
| 262 | if (!copy_from_iter_full(kbuf, len, from)) { |
| 263 | ret = -EFAULT; |
| 264 | goto free_kbuf; |
| 265 | } |
| 266 | |
| 267 | if (mutex_lock_interruptible(&eptdev->ept_lock)) { |
| 268 | ret = -ERESTARTSYS; |
| 269 | goto free_kbuf; |
| 270 | } |
| 271 | |
| 272 | if (!eptdev->ept) { |
| 273 | ret = -EPIPE; |
| 274 | goto unlock_eptdev; |
| 275 | } |
| 276 | |
| 277 | if (filp->f_flags & O_NONBLOCK) { |
| 278 | ret = rpmsg_trysendto(eptdev->ept, kbuf, len, eptdev->chinfo.dst); |
| 279 | if (ret == -ENOMEM) |
| 280 | ret = -EAGAIN; |
| 281 | } else { |
| 282 | ret = rpmsg_sendto(eptdev->ept, kbuf, len, eptdev->chinfo.dst); |
| 283 | } |
| 284 | |
| 285 | unlock_eptdev: |
| 286 | mutex_unlock(&eptdev->ept_lock); |
| 287 | |
| 288 | free_kbuf: |
| 289 | kfree(kbuf); |
| 290 | return ret < 0 ? ret : len; |
| 291 | } |
| 292 | |
| 293 | static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait) |
| 294 | { |
| 295 | struct rpmsg_eptdev *eptdev = filp->private_data; |
| 296 | __poll_t mask = 0; |
| 297 | |
| 298 | if (!eptdev->ept) |
| 299 | return EPOLLERR; |
| 300 | |
| 301 | poll_wait(filp, &eptdev->readq, wait); |
| 302 | |
| 303 | if (!skb_queue_empty(&eptdev->queue)) |
| 304 | mask |= EPOLLIN | EPOLLRDNORM; |
| 305 | |
| 306 | if (eptdev->remote_flow_updated) |
| 307 | mask |= EPOLLPRI; |
| 308 | |
| 309 | mutex_lock(&eptdev->ept_lock); |
| 310 | mask |= rpmsg_poll(eptdev->ept, filp, wait); |
| 311 | mutex_unlock(&eptdev->ept_lock); |
| 312 | |
| 313 | return mask; |
| 314 | } |
| 315 | |
| 316 | static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd, |
| 317 | unsigned long arg) |
| 318 | { |
| 319 | struct rpmsg_eptdev *eptdev = fp->private_data; |
| 320 | |
| 321 | bool set; |
| 322 | int ret; |
| 323 | |
| 324 | switch (cmd) { |
| 325 | case RPMSG_GET_OUTGOING_FLOWCONTROL: |
| 326 | eptdev->remote_flow_updated = false; |
| 327 | ret = put_user(eptdev->remote_flow_restricted, (int __user *)arg); |
| 328 | break; |
| 329 | case RPMSG_SET_INCOMING_FLOWCONTROL: |
| 330 | if (arg > 1) { |
| 331 | ret = -EINVAL; |
| 332 | break; |
| 333 | } |
| 334 | set = !!arg; |
| 335 | ret = rpmsg_set_flow_control(eptdev->ept, set, eptdev->chinfo.dst); |
| 336 | break; |
| 337 | case RPMSG_DESTROY_EPT_IOCTL: |
| 338 | /* Don't allow to destroy a default endpoint. */ |
| 339 | if (eptdev->default_ept) { |
| 340 | ret = -EINVAL; |
| 341 | break; |
| 342 | } |
| 343 | ret = rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL); |
| 344 | break; |
| 345 | default: |
| 346 | ret = -EINVAL; |
| 347 | } |
| 348 | |
| 349 | return ret; |
| 350 | } |
| 351 | |
| 352 | static const struct file_operations rpmsg_eptdev_fops = { |
| 353 | .owner = THIS_MODULE, |
| 354 | .open = rpmsg_eptdev_open, |
| 355 | .release = rpmsg_eptdev_release, |
| 356 | .read_iter = rpmsg_eptdev_read_iter, |
| 357 | .write_iter = rpmsg_eptdev_write_iter, |
| 358 | .poll = rpmsg_eptdev_poll, |
| 359 | .unlocked_ioctl = rpmsg_eptdev_ioctl, |
| 360 | .compat_ioctl = compat_ptr_ioctl, |
| 361 | }; |
| 362 | |
| 363 | static ssize_t name_show(struct device *dev, struct device_attribute *attr, |
| 364 | char *buf) |
| 365 | { |
| 366 | struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev); |
| 367 | |
| 368 | return sprintf(buf, "%s\n", eptdev->chinfo.name); |
| 369 | } |
| 370 | static DEVICE_ATTR_RO(name); |
| 371 | |
| 372 | static ssize_t src_show(struct device *dev, struct device_attribute *attr, |
| 373 | char *buf) |
| 374 | { |
| 375 | struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev); |
| 376 | |
| 377 | return sprintf(buf, "%d\n", eptdev->chinfo.src); |
| 378 | } |
| 379 | static DEVICE_ATTR_RO(src); |
| 380 | |
| 381 | static ssize_t dst_show(struct device *dev, struct device_attribute *attr, |
| 382 | char *buf) |
| 383 | { |
| 384 | struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev); |
| 385 | |
| 386 | return sprintf(buf, "%d\n", eptdev->chinfo.dst); |
| 387 | } |
| 388 | static DEVICE_ATTR_RO(dst); |
| 389 | |
| 390 | static struct attribute *rpmsg_eptdev_attrs[] = { |
| 391 | &dev_attr_name.attr, |
| 392 | &dev_attr_src.attr, |
| 393 | &dev_attr_dst.attr, |
| 394 | NULL |
| 395 | }; |
| 396 | ATTRIBUTE_GROUPS(rpmsg_eptdev); |
| 397 | |
| 398 | static void rpmsg_eptdev_release_device(struct device *dev) |
| 399 | { |
| 400 | struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev); |
| 401 | |
| 402 | ida_free(&rpmsg_ept_ida, dev->id); |
| 403 | ida_free(&rpmsg_minor_ida, MINOR(eptdev->dev.devt)); |
| 404 | kfree(eptdev); |
| 405 | } |
| 406 | |
| 407 | static struct rpmsg_eptdev *rpmsg_chrdev_eptdev_alloc(struct rpmsg_device *rpdev, |
| 408 | struct device *parent) |
| 409 | { |
| 410 | struct rpmsg_eptdev *eptdev; |
| 411 | struct device *dev; |
| 412 | |
| 413 | eptdev = kzalloc(sizeof(*eptdev), GFP_KERNEL); |
| 414 | if (!eptdev) |
| 415 | return ERR_PTR(-ENOMEM); |
| 416 | |
| 417 | dev = &eptdev->dev; |
| 418 | eptdev->rpdev = rpdev; |
| 419 | |
| 420 | mutex_init(&eptdev->ept_lock); |
| 421 | spin_lock_init(&eptdev->queue_lock); |
| 422 | skb_queue_head_init(&eptdev->queue); |
| 423 | init_waitqueue_head(&eptdev->readq); |
| 424 | |
| 425 | device_initialize(dev); |
| 426 | dev->class = &rpmsg_class; |
| 427 | dev->parent = parent; |
| 428 | dev->groups = rpmsg_eptdev_groups; |
| 429 | dev_set_drvdata(dev, eptdev); |
| 430 | |
| 431 | cdev_init(&eptdev->cdev, &rpmsg_eptdev_fops); |
| 432 | eptdev->cdev.owner = THIS_MODULE; |
| 433 | |
| 434 | return eptdev; |
| 435 | } |
| 436 | |
| 437 | static int rpmsg_chrdev_eptdev_add(struct rpmsg_eptdev *eptdev, struct rpmsg_channel_info chinfo) |
| 438 | { |
| 439 | struct device *dev = &eptdev->dev; |
| 440 | int ret; |
| 441 | |
| 442 | eptdev->chinfo = chinfo; |
| 443 | |
| 444 | ret = ida_alloc_max(&rpmsg_minor_ida, RPMSG_DEV_MAX - 1, GFP_KERNEL); |
| 445 | if (ret < 0) |
| 446 | goto free_eptdev; |
| 447 | dev->devt = MKDEV(MAJOR(rpmsg_major), ret); |
| 448 | |
| 449 | ret = ida_alloc(&rpmsg_ept_ida, GFP_KERNEL); |
| 450 | if (ret < 0) |
| 451 | goto free_minor_ida; |
| 452 | dev->id = ret; |
| 453 | dev_set_name(dev, "rpmsg%d", ret); |
| 454 | |
| 455 | ret = cdev_device_add(&eptdev->cdev, &eptdev->dev); |
| 456 | if (ret) |
| 457 | goto free_ept_ida; |
| 458 | |
| 459 | /* We can now rely on the release function for cleanup */ |
| 460 | dev->release = rpmsg_eptdev_release_device; |
| 461 | |
| 462 | return ret; |
| 463 | |
| 464 | free_ept_ida: |
| 465 | ida_free(&rpmsg_ept_ida, dev->id); |
| 466 | free_minor_ida: |
| 467 | ida_free(&rpmsg_minor_ida, MINOR(dev->devt)); |
| 468 | free_eptdev: |
| 469 | put_device(dev); |
| 470 | kfree(eptdev); |
| 471 | |
| 472 | return ret; |
| 473 | } |
| 474 | |
| 475 | int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent, |
| 476 | struct rpmsg_channel_info chinfo) |
| 477 | { |
| 478 | struct rpmsg_eptdev *eptdev; |
| 479 | |
| 480 | eptdev = rpmsg_chrdev_eptdev_alloc(rpdev, parent); |
| 481 | if (IS_ERR(eptdev)) |
| 482 | return PTR_ERR(eptdev); |
| 483 | |
| 484 | return rpmsg_chrdev_eptdev_add(eptdev, chinfo); |
| 485 | } |
| 486 | EXPORT_SYMBOL(rpmsg_chrdev_eptdev_create); |
| 487 | |
| 488 | static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev) |
| 489 | { |
| 490 | struct rpmsg_channel_info chinfo; |
| 491 | struct rpmsg_eptdev *eptdev; |
| 492 | struct device *dev = &rpdev->dev; |
| 493 | |
| 494 | memcpy(chinfo.name, rpdev->id.name, RPMSG_NAME_SIZE); |
| 495 | chinfo.src = rpdev->src; |
| 496 | chinfo.dst = rpdev->dst; |
| 497 | |
| 498 | eptdev = rpmsg_chrdev_eptdev_alloc(rpdev, dev); |
| 499 | if (IS_ERR(eptdev)) |
| 500 | return PTR_ERR(eptdev); |
| 501 | |
| 502 | /* Set the default_ept to the rpmsg device endpoint */ |
| 503 | eptdev->default_ept = rpdev->ept; |
| 504 | |
| 505 | /* |
| 506 | * The rpmsg_ept_cb uses *priv parameter to get its rpmsg_eptdev context. |
| 507 | * Storedit in default_ept *priv field. |
| 508 | */ |
| 509 | eptdev->default_ept->priv = eptdev; |
| 510 | |
| 511 | return rpmsg_chrdev_eptdev_add(eptdev, chinfo); |
| 512 | } |
| 513 | |
| 514 | static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev) |
| 515 | { |
| 516 | int ret; |
| 517 | |
| 518 | ret = device_for_each_child(&rpdev->dev, NULL, rpmsg_chrdev_eptdev_destroy); |
| 519 | if (ret) |
| 520 | dev_warn(&rpdev->dev, "failed to destroy endpoints: %d\n", ret); |
| 521 | } |
| 522 | |
| 523 | static struct rpmsg_device_id rpmsg_chrdev_id_table[] = { |
| 524 | { .name = "rpmsg-raw" }, |
| 525 | { }, |
| 526 | }; |
| 527 | |
| 528 | static struct rpmsg_driver rpmsg_chrdev_driver = { |
| 529 | .probe = rpmsg_chrdev_probe, |
| 530 | .remove = rpmsg_chrdev_remove, |
| 531 | .callback = rpmsg_ept_cb, |
| 532 | .id_table = rpmsg_chrdev_id_table, |
| 533 | .drv.name = "rpmsg_chrdev", |
| 534 | }; |
| 535 | |
| 536 | static int rpmsg_chrdev_init(void) |
| 537 | { |
| 538 | int ret; |
| 539 | |
| 540 | ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg_char"); |
| 541 | if (ret < 0) { |
| 542 | pr_err("failed to allocate char dev region\n"); |
| 543 | return ret; |
| 544 | } |
| 545 | |
| 546 | ret = register_rpmsg_driver(&rpmsg_chrdev_driver); |
| 547 | if (ret < 0) { |
| 548 | pr_err("rpmsg: failed to register rpmsg raw driver\n"); |
| 549 | goto free_region; |
| 550 | } |
| 551 | |
| 552 | return 0; |
| 553 | |
| 554 | free_region: |
| 555 | unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); |
| 556 | |
| 557 | return ret; |
| 558 | } |
| 559 | postcore_initcall(rpmsg_chrdev_init); |
| 560 | |
| 561 | static void rpmsg_chrdev_exit(void) |
| 562 | { |
| 563 | unregister_rpmsg_driver(&rpmsg_chrdev_driver); |
| 564 | unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); |
| 565 | } |
| 566 | module_exit(rpmsg_chrdev_exit); |
| 567 | |
| 568 | MODULE_ALIAS("rpmsg:rpmsg_chrdev"); |
| 569 | MODULE_DESCRIPTION("RPMSG device interface"); |
| 570 | MODULE_LICENSE("GPL v2"); |