1 // SPDX-License-Identifier: GPL-2.0-or-later
4 * Bluetooth virtual HCI driver
6 * Copyright (C) 2000-2001 Qualcomm Incorporated
7 * Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com>
8 * Copyright (C) 2004-2006 Marcel Holtmann <marcel@holtmann.org>
11 #include <linux/module.h>
12 #include <asm/unaligned.h>
14 #include <linux/atomic.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <linux/types.h>
19 #include <linux/errno.h>
20 #include <linux/sched.h>
21 #include <linux/poll.h>
23 #include <linux/skbuff.h>
24 #include <linux/miscdevice.h>
25 #include <linux/debugfs.h>
27 #include <net/bluetooth/bluetooth.h>
28 #include <net/bluetooth/hci_core.h>
37 wait_queue_head_t read_wait;
38 struct sk_buff_head readq;
40 struct mutex open_mutex;
41 struct delayed_work open_timeout;
42 struct work_struct suspend_work;
51 static int vhci_open_dev(struct hci_dev *hdev)
56 static int vhci_close_dev(struct hci_dev *hdev)
58 struct vhci_data *data = hci_get_drvdata(hdev);
60 skb_queue_purge(&data->readq);
65 static int vhci_flush(struct hci_dev *hdev)
67 struct vhci_data *data = hci_get_drvdata(hdev);
69 skb_queue_purge(&data->readq);
74 static int vhci_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
76 struct vhci_data *data = hci_get_drvdata(hdev);
78 memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
80 skb_queue_tail(&data->readq, skb);
82 if (atomic_read(&data->initialized))
83 wake_up_interruptible(&data->read_wait);
87 static int vhci_get_data_path_id(struct hci_dev *hdev, u8 *data_path_id)
93 static int vhci_get_codec_config_data(struct hci_dev *hdev, __u8 type,
94 struct bt_codec *codec, __u8 *vnd_len,
97 if (type != ESCO_LINK)
105 static bool vhci_wakeup(struct hci_dev *hdev)
107 struct vhci_data *data = hci_get_drvdata(hdev);
112 static ssize_t force_suspend_read(struct file *file, char __user *user_buf,
113 size_t count, loff_t *ppos)
115 struct vhci_data *data = file->private_data;
118 buf[0] = data->suspended ? 'Y' : 'N';
121 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
124 static void vhci_suspend_work(struct work_struct *work)
126 struct vhci_data *data = container_of(work, struct vhci_data,
130 hci_suspend_dev(data->hdev);
132 hci_resume_dev(data->hdev);
135 static ssize_t force_suspend_write(struct file *file,
136 const char __user *user_buf,
137 size_t count, loff_t *ppos)
139 struct vhci_data *data = file->private_data;
143 err = kstrtobool_from_user(user_buf, count, &enable);
147 if (data->suspended == enable)
150 data->suspended = enable;
152 schedule_work(&data->suspend_work);
157 static const struct file_operations force_suspend_fops = {
159 .read = force_suspend_read,
160 .write = force_suspend_write,
161 .llseek = default_llseek,
164 static ssize_t force_wakeup_read(struct file *file, char __user *user_buf,
165 size_t count, loff_t *ppos)
167 struct vhci_data *data = file->private_data;
170 buf[0] = data->wakeup ? 'Y' : 'N';
173 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
176 static ssize_t force_wakeup_write(struct file *file,
177 const char __user *user_buf, size_t count,
180 struct vhci_data *data = file->private_data;
184 err = kstrtobool_from_user(user_buf, count, &enable);
188 if (data->wakeup == enable)
191 data->wakeup = enable;
196 static const struct file_operations force_wakeup_fops = {
198 .read = force_wakeup_read,
199 .write = force_wakeup_write,
200 .llseek = default_llseek,
203 static int msft_opcode_set(void *data, u64 val)
205 struct vhci_data *vhci = data;
207 if (val > 0xffff || hci_opcode_ogf(val) != 0x3f)
210 if (vhci->msft_opcode)
213 vhci->msft_opcode = val;
218 static int msft_opcode_get(void *data, u64 *val)
220 struct vhci_data *vhci = data;
222 *val = vhci->msft_opcode;
227 DEFINE_DEBUGFS_ATTRIBUTE(msft_opcode_fops, msft_opcode_get, msft_opcode_set,
230 static ssize_t aosp_capable_read(struct file *file, char __user *user_buf,
231 size_t count, loff_t *ppos)
233 struct vhci_data *vhci = file->private_data;
236 buf[0] = vhci->aosp_capable ? 'Y' : 'N';
239 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
242 static ssize_t aosp_capable_write(struct file *file,
243 const char __user *user_buf, size_t count,
246 struct vhci_data *vhci = file->private_data;
250 err = kstrtobool_from_user(user_buf, count, &enable);
257 if (vhci->aosp_capable)
260 vhci->aosp_capable = enable;
265 static const struct file_operations aosp_capable_fops = {
267 .read = aosp_capable_read,
268 .write = aosp_capable_write,
269 .llseek = default_llseek,
272 static int vhci_setup(struct hci_dev *hdev)
274 struct vhci_data *vhci = hci_get_drvdata(hdev);
276 if (vhci->msft_opcode)
277 hci_set_msft_opcode(hdev, vhci->msft_opcode);
279 if (vhci->aosp_capable)
280 hci_set_aosp_capable(hdev);
285 static void vhci_coredump(struct hci_dev *hdev)
287 /* No need to do anything */
290 static void vhci_coredump_hdr(struct hci_dev *hdev, struct sk_buff *skb)
294 snprintf(buf, sizeof(buf), "Controller Name: vhci_ctrl\n");
295 skb_put_data(skb, buf, strlen(buf));
297 snprintf(buf, sizeof(buf), "Firmware Version: vhci_fw\n");
298 skb_put_data(skb, buf, strlen(buf));
300 snprintf(buf, sizeof(buf), "Driver: vhci_drv\n");
301 skb_put_data(skb, buf, strlen(buf));
303 snprintf(buf, sizeof(buf), "Vendor: vhci\n");
304 skb_put_data(skb, buf, strlen(buf));
307 #define MAX_COREDUMP_LINE_LEN 40
309 struct devcoredump_test_data {
310 enum devcoredump_state state;
311 unsigned int timeout;
312 char data[MAX_COREDUMP_LINE_LEN];
315 static inline void force_devcd_timeout(struct hci_dev *hdev,
316 unsigned int timeout)
318 #ifdef CONFIG_DEV_COREDUMP
319 hdev->dump.timeout = msecs_to_jiffies(timeout * 1000);
323 static ssize_t force_devcd_write(struct file *file, const char __user *user_buf,
324 size_t count, loff_t *ppos)
326 struct vhci_data *data = file->private_data;
327 struct hci_dev *hdev = data->hdev;
328 struct sk_buff *skb = NULL;
329 struct devcoredump_test_data dump_data;
333 if (count < offsetof(struct devcoredump_test_data, data) ||
334 count > sizeof(dump_data))
337 if (copy_from_user(&dump_data, user_buf, count))
340 data_size = count - offsetof(struct devcoredump_test_data, data);
341 skb = alloc_skb(data_size, GFP_ATOMIC);
344 skb_put_data(skb, &dump_data.data, data_size);
346 hci_devcd_register(hdev, vhci_coredump, vhci_coredump_hdr, NULL);
348 /* Force the devcoredump timeout */
349 if (dump_data.timeout)
350 force_devcd_timeout(hdev, dump_data.timeout);
352 ret = hci_devcd_init(hdev, skb->len);
354 BT_ERR("Failed to generate devcoredump");
359 hci_devcd_append(hdev, skb);
361 switch (dump_data.state) {
362 case HCI_DEVCOREDUMP_DONE:
363 hci_devcd_complete(hdev);
365 case HCI_DEVCOREDUMP_ABORT:
366 hci_devcd_abort(hdev);
368 case HCI_DEVCOREDUMP_TIMEOUT:
378 static const struct file_operations force_devcoredump_fops = {
380 .write = force_devcd_write,
383 static int __vhci_create_device(struct vhci_data *data, __u8 opcode)
385 struct hci_dev *hdev;
392 /* bits 0-1 are dev_type (Primary or AMP) */
393 dev_type = opcode & 0x03;
395 if (dev_type != HCI_PRIMARY && dev_type != HCI_AMP)
398 /* bits 2-5 are reserved (must be zero) */
402 skb = bt_skb_alloc(4, GFP_KERNEL);
406 hdev = hci_alloc_dev();
414 hdev->bus = HCI_VIRTUAL;
415 hdev->dev_type = dev_type;
416 hci_set_drvdata(hdev, data);
418 hdev->open = vhci_open_dev;
419 hdev->close = vhci_close_dev;
420 hdev->flush = vhci_flush;
421 hdev->send = vhci_send_frame;
422 hdev->get_data_path_id = vhci_get_data_path_id;
423 hdev->get_codec_config_data = vhci_get_codec_config_data;
424 hdev->wakeup = vhci_wakeup;
425 hdev->setup = vhci_setup;
426 set_bit(HCI_QUIRK_NON_PERSISTENT_SETUP, &hdev->quirks);
428 /* bit 6 is for external configuration */
430 set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
432 /* bit 7 is for raw device */
434 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
436 set_bit(HCI_QUIRK_VALID_LE_STATES, &hdev->quirks);
438 if (hci_register_dev(hdev) < 0) {
439 BT_ERR("Can't register HCI device");
446 debugfs_create_file("force_suspend", 0644, hdev->debugfs, data,
447 &force_suspend_fops);
449 debugfs_create_file("force_wakeup", 0644, hdev->debugfs, data,
452 if (IS_ENABLED(CONFIG_BT_MSFTEXT))
453 debugfs_create_file("msft_opcode", 0644, hdev->debugfs, data,
456 if (IS_ENABLED(CONFIG_BT_AOSPEXT))
457 debugfs_create_file("aosp_capable", 0644, hdev->debugfs, data,
460 debugfs_create_file("force_devcoredump", 0644, hdev->debugfs, data,
461 &force_devcoredump_fops);
463 hci_skb_pkt_type(skb) = HCI_VENDOR_PKT;
465 skb_put_u8(skb, 0xff);
466 skb_put_u8(skb, opcode);
467 put_unaligned_le16(hdev->id, skb_put(skb, 2));
468 skb_queue_head(&data->readq, skb);
469 atomic_inc(&data->initialized);
471 wake_up_interruptible(&data->read_wait);
475 static int vhci_create_device(struct vhci_data *data, __u8 opcode)
479 mutex_lock(&data->open_mutex);
480 err = __vhci_create_device(data, opcode);
481 mutex_unlock(&data->open_mutex);
486 static inline ssize_t vhci_get_user(struct vhci_data *data,
487 struct iov_iter *from)
489 size_t len = iov_iter_count(from);
491 __u8 pkt_type, opcode;
494 if (len < 2 || len > HCI_MAX_FRAME_SIZE)
497 skb = bt_skb_alloc(len, GFP_KERNEL);
501 if (!copy_from_iter_full(skb_put(skb, len), len, from)) {
506 pkt_type = *((__u8 *) skb->data);
511 case HCI_ACLDATA_PKT:
512 case HCI_SCODATA_PKT:
513 case HCI_ISODATA_PKT:
519 hci_skb_pkt_type(skb) = pkt_type;
521 ret = hci_recv_frame(data->hdev, skb);
525 cancel_delayed_work_sync(&data->open_timeout);
527 opcode = *((__u8 *) skb->data);
537 ret = vhci_create_device(data, opcode);
545 return (ret < 0) ? ret : len;
548 static inline ssize_t vhci_put_user(struct vhci_data *data,
550 char __user *buf, int count)
552 char __user *ptr = buf;
555 len = min_t(unsigned int, skb->len, count);
557 if (copy_to_user(ptr, skb->data, len))
563 data->hdev->stat.byte_tx += len;
565 switch (hci_skb_pkt_type(skb)) {
566 case HCI_COMMAND_PKT:
567 data->hdev->stat.cmd_tx++;
569 case HCI_ACLDATA_PKT:
570 data->hdev->stat.acl_tx++;
572 case HCI_SCODATA_PKT:
573 data->hdev->stat.sco_tx++;
580 static ssize_t vhci_read(struct file *file,
581 char __user *buf, size_t count, loff_t *pos)
583 struct vhci_data *data = file->private_data;
588 skb = skb_dequeue(&data->readq);
590 ret = vhci_put_user(data, skb, buf, count);
592 skb_queue_head(&data->readq, skb);
598 if (file->f_flags & O_NONBLOCK) {
603 ret = wait_event_interruptible(data->read_wait,
604 !skb_queue_empty(&data->readq));
612 static ssize_t vhci_write(struct kiocb *iocb, struct iov_iter *from)
614 struct file *file = iocb->ki_filp;
615 struct vhci_data *data = file->private_data;
617 return vhci_get_user(data, from);
620 static __poll_t vhci_poll(struct file *file, poll_table *wait)
622 struct vhci_data *data = file->private_data;
624 poll_wait(file, &data->read_wait, wait);
626 if (!skb_queue_empty(&data->readq))
627 return EPOLLIN | EPOLLRDNORM;
629 return EPOLLOUT | EPOLLWRNORM;
632 static void vhci_open_timeout(struct work_struct *work)
634 struct vhci_data *data = container_of(work, struct vhci_data,
637 vhci_create_device(data, amp ? HCI_AMP : HCI_PRIMARY);
640 static int vhci_open(struct inode *inode, struct file *file)
642 struct vhci_data *data;
644 data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL);
648 skb_queue_head_init(&data->readq);
649 init_waitqueue_head(&data->read_wait);
651 mutex_init(&data->open_mutex);
652 INIT_DELAYED_WORK(&data->open_timeout, vhci_open_timeout);
653 INIT_WORK(&data->suspend_work, vhci_suspend_work);
655 file->private_data = data;
656 nonseekable_open(inode, file);
658 schedule_delayed_work(&data->open_timeout, msecs_to_jiffies(1000));
663 static int vhci_release(struct inode *inode, struct file *file)
665 struct vhci_data *data = file->private_data;
666 struct hci_dev *hdev;
668 cancel_delayed_work_sync(&data->open_timeout);
669 flush_work(&data->suspend_work);
674 hci_unregister_dev(hdev);
678 skb_queue_purge(&data->readq);
679 file->private_data = NULL;
685 static const struct file_operations vhci_fops = {
686 .owner = THIS_MODULE,
688 .write_iter = vhci_write,
691 .release = vhci_release,
695 static struct miscdevice vhci_miscdev = {
700 module_misc_device(vhci_miscdev);
702 module_param(amp, bool, 0644);
703 MODULE_PARM_DESC(amp, "Create AMP controller device");
705 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
706 MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION);
707 MODULE_VERSION(VERSION);
708 MODULE_LICENSE("GPL");
709 MODULE_ALIAS("devname:vhci");
710 MODULE_ALIAS_MISCDEV(VHCI_MINOR);