1 // SPDX-License-Identifier: GPL-2.0
2 /* vcc.c: sun4v virtual channel concentrator
4 * Copyright (C) 2017 Oracle. All rights reserved.
7 #include <linux/delay.h>
8 #include <linux/interrupt.h>
9 #include <linux/module.h>
10 #include <linux/slab.h>
11 #include <linux/sysfs.h>
12 #include <linux/tty.h>
13 #include <linux/tty_flip.h>
17 #define DRV_MODULE_NAME "vcc"
18 #define DRV_MODULE_VERSION "1.1"
19 #define DRV_MODULE_RELDATE "July 1, 2017"
21 static char version[] =
22 DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")";
24 MODULE_DESCRIPTION("Sun LDOM virtual console concentrator driver");
25 MODULE_LICENSE("GPL");
26 MODULE_VERSION(DRV_MODULE_VERSION);
29 struct vio_driver_state vio;
33 struct tty_struct *tty; /* only populated while dev is open */
34 unsigned long index; /* index into the vcc_table */
41 /* This buffer is required to support the tty write_room interface
42 * and guarantee that any characters that the driver accepts will
43 * be eventually sent, either immediately or later.
46 struct vio_vcc buffer;
48 struct timer_list rx_timer;
49 struct timer_list tx_timer;
52 /* Microseconds that thread will delay waiting for a vcc port ref */
53 #define VCC_REF_DELAY 100
55 #define VCC_MAX_PORTS 1024
56 #define VCC_MINOR_START 0 /* must be zero */
57 #define VCC_BUFF_LEN VIO_VCC_MTU_SIZE
59 #define VCC_CTL_BREAK -1
60 #define VCC_CTL_HUP -2
62 static const char vcc_driver_name[] = "vcc";
63 static const char vcc_device_node[] = "vcc";
64 static struct tty_driver *vcc_tty_driver;
66 static struct vcc_port *vcc_table[VCC_MAX_PORTS];
67 static DEFINE_SPINLOCK(vcc_table_lock);
73 module_param(vcc_dbg, uint, 0664);
74 module_param(vcc_dbg_ldc, uint, 0664);
75 module_param(vcc_dbg_vio, uint, 0664);
77 #define VCC_DBG_DRV 0x1
78 #define VCC_DBG_LDC 0x2
79 #define VCC_DBG_PKT 0x4
81 #define vccdbg(f, a...) \
83 if (vcc_dbg & VCC_DBG_DRV) \
89 if (vcc_dbg & VCC_DBG_LDC) \
93 #define vccdbgp(pkt) \
95 if (vcc_dbg & VCC_DBG_PKT) { \
97 for (i = 0; i < pkt.tag.stype; i++) \
98 pr_info("[%c]", pkt.data[i]); \
102 /* Note: Be careful when adding flags to this line discipline. Don't
103 * add anything that will cause echoing or we'll go into recursive
104 * loop echoing chars back and forth with the console drivers.
106 static const struct ktermios vcc_tty_termios = {
107 .c_iflag = IGNBRK | IGNPAR,
109 .c_cflag = B38400 | CS8 | CREAD | HUPCL,
116 * vcc_table_add() - Add VCC port to the VCC table
117 * @port: pointer to the VCC port
119 * Return: index of the port in the VCC table on success,
122 static int vcc_table_add(struct vcc_port *port)
127 spin_lock_irqsave(&vcc_table_lock, flags);
128 for (i = VCC_MINOR_START; i < VCC_MAX_PORTS; i++) {
134 spin_unlock_irqrestore(&vcc_table_lock, flags);
136 if (i < VCC_MAX_PORTS)
143 * vcc_table_remove() - Removes a VCC port from the VCC table
144 * @index: Index into the VCC table
146 static void vcc_table_remove(unsigned long index)
150 if (WARN_ON(index >= VCC_MAX_PORTS))
153 spin_lock_irqsave(&vcc_table_lock, flags);
154 vcc_table[index] = NULL;
155 spin_unlock_irqrestore(&vcc_table_lock, flags);
159 * vcc_get() - Gets a reference to VCC port
160 * @index: Index into the VCC table
161 * @excl: Indicates if an exclusive access is requested
163 * Return: reference to the VCC port, if found
164 * NULL, if port not found
166 static struct vcc_port *vcc_get(unsigned long index, bool excl)
168 struct vcc_port *port;
172 spin_lock_irqsave(&vcc_table_lock, flags);
174 port = vcc_table[index];
176 spin_unlock_irqrestore(&vcc_table_lock, flags);
181 if (port->excl_locked) {
182 spin_unlock_irqrestore(&vcc_table_lock, flags);
183 udelay(VCC_REF_DELAY);
187 spin_unlock_irqrestore(&vcc_table_lock, flags);
192 spin_unlock_irqrestore(&vcc_table_lock, flags);
193 /* Threads wanting exclusive access will wait half the time,
194 * probably giving them higher priority in the case of
197 udelay(VCC_REF_DELAY/2);
202 port->excl_locked = true;
203 spin_unlock_irqrestore(&vcc_table_lock, flags);
209 * vcc_put() - Returns a reference to VCC port
210 * @port: pointer to VCC port
211 * @excl: Indicates if the returned reference is an exclusive reference
213 * Note: It's the caller's responsibility to ensure the correct value
216 static void vcc_put(struct vcc_port *port, bool excl)
223 spin_lock_irqsave(&vcc_table_lock, flags);
225 /* check if caller attempted to put with the wrong flags */
226 if (WARN_ON((excl && !port->excl_locked) ||
227 (!excl && port->excl_locked)))
233 port->excl_locked = false;
236 spin_unlock_irqrestore(&vcc_table_lock, flags);
240 * vcc_get_ne() - Get a non-exclusive reference to VCC port
241 * @index: Index into the VCC table
243 * Gets a non-exclusive reference to VCC port, if it's not removed
245 * Return: pointer to the VCC port, if found
246 * NULL, if port not found
248 static struct vcc_port *vcc_get_ne(unsigned long index)
250 struct vcc_port *port;
252 port = vcc_get(index, false);
254 if (port && port->removed) {
255 vcc_put(port, false);
262 static void vcc_kick_rx(struct vcc_port *port)
264 struct vio_driver_state *vio = &port->vio;
266 assert_spin_locked(&port->lock);
268 if (!timer_pending(&port->rx_timer) && !port->removed) {
269 disable_irq_nosync(vio->vdev->rx_irq);
270 port->rx_timer.expires = (jiffies + 1);
271 add_timer(&port->rx_timer);
275 static void vcc_kick_tx(struct vcc_port *port)
277 assert_spin_locked(&port->lock);
279 if (!timer_pending(&port->tx_timer) && !port->removed) {
280 port->tx_timer.expires = (jiffies + 1);
281 add_timer(&port->tx_timer);
285 static int vcc_rx_check(struct tty_struct *tty, int size)
287 if (WARN_ON(!tty || !tty->port))
290 /* tty_buffer_request_room won't sleep because it uses
291 * GFP_ATOMIC flag to allocate buffer
293 if (test_bit(TTY_THROTTLED, &tty->flags) ||
294 (tty_buffer_request_room(tty->port, VCC_BUFF_LEN) < VCC_BUFF_LEN))
300 static int vcc_rx(struct tty_struct *tty, char *buf, int size)
304 if (WARN_ON(!tty || !tty->port))
307 len = tty_insert_flip_string(tty->port, buf, size);
309 tty_flip_buffer_push(tty->port);
314 static int vcc_ldc_read(struct vcc_port *port)
316 struct vio_driver_state *vio = &port->vio;
317 struct tty_struct *tty;
323 rv = ldc_rx_reset(vio->lp);
324 vccdbg("VCC: reset rx q: rv=%d\n", rv);
328 /* Read as long as LDC has incoming data. */
330 if (!vcc_rx_check(tty, VIO_VCC_MTU_SIZE)) {
337 rv = ldc_read(vio->lp, &pkt, sizeof(pkt));
341 vccdbg("VCC: ldc_read()=%d\n", rv);
342 vccdbg("TAG [%02x:%02x:%04x:%08x]\n",
343 pkt.tag.type, pkt.tag.stype,
344 pkt.tag.stype_env, pkt.tag.sid);
346 if (pkt.tag.type == VIO_TYPE_DATA) {
348 /* vcc_rx_check ensures memory availability */
349 vcc_rx(tty, pkt.data, pkt.tag.stype);
351 pr_err("VCC: unknown msg [%02x:%02x:%04x:%08x]\n",
352 pkt.tag.type, pkt.tag.stype,
353 pkt.tag.stype_env, pkt.tag.sid);
358 WARN_ON(rv != LDC_PACKET_SIZE);
365 static void vcc_rx_timer(struct timer_list *t)
367 struct vcc_port *port = from_timer(port, t, rx_timer);
368 struct vio_driver_state *vio;
372 spin_lock_irqsave(&port->lock, flags);
373 port->rx_timer.expires = 0;
377 enable_irq(vio->vdev->rx_irq);
379 if (!port->tty || port->removed)
382 rv = vcc_ldc_read(port);
383 if (rv == -ECONNRESET)
387 spin_unlock_irqrestore(&port->lock, flags);
388 vcc_put(port, false);
391 static void vcc_tx_timer(struct timer_list *t)
393 struct vcc_port *port = from_timer(port, t, tx_timer);
399 spin_lock_irqsave(&port->lock, flags);
400 port->tx_timer.expires = 0;
402 if (!port->tty || port->removed)
405 tosend = min(VCC_BUFF_LEN, port->chars_in_buffer);
410 pkt->tag.type = VIO_TYPE_DATA;
411 pkt->tag.stype = tosend;
412 vccdbgl(port->vio.lp);
414 rv = ldc_write(port->vio.lp, pkt, (VIO_TAG_SIZE + tosend));
418 vccdbg("VCC: ldc_write()=%d\n", rv);
421 struct tty_struct *tty = port->tty;
423 port->chars_in_buffer = 0;
429 spin_unlock_irqrestore(&port->lock, flags);
430 vcc_put(port, false);
434 * vcc_event() - LDC event processing engine
435 * @arg: VCC private data
438 * Handles LDC events for VCC
440 static void vcc_event(void *arg, int event)
442 struct vio_driver_state *vio;
443 struct vcc_port *port;
450 spin_lock_irqsave(&port->lock, flags);
453 case LDC_EVENT_RESET:
455 vio_link_state_change(vio, event);
458 case LDC_EVENT_DATA_READY:
459 rv = vcc_ldc_read(port);
460 if (rv == -ECONNRESET)
465 pr_err("VCC: unexpected LDC event(%d)\n", event);
468 spin_unlock_irqrestore(&port->lock, flags);
471 static struct ldc_channel_config vcc_ldc_cfg = {
473 .mtu = VIO_VCC_MTU_SIZE,
474 .mode = LDC_MODE_RAW,
478 /* Ordered from largest major to lowest */
479 static struct vio_version vcc_versions[] = {
480 { .major = 1, .minor = 0 },
483 static struct tty_port_operations vcc_port_ops = { 0 };
485 static ssize_t vcc_sysfs_domain_show(struct device *dev,
486 struct device_attribute *attr,
489 struct vcc_port *port;
492 port = dev_get_drvdata(dev);
496 rv = scnprintf(buf, PAGE_SIZE, "%s\n", port->domain);
501 static int vcc_send_ctl(struct vcc_port *port, int ctl)
506 pkt.tag.type = VIO_TYPE_CTRL;
510 rv = ldc_write(port->vio.lp, &pkt, sizeof(pkt.tag));
512 vccdbg("VCC: ldc_write(%ld)=%d\n", sizeof(pkt.tag), rv);
517 static ssize_t vcc_sysfs_break_store(struct device *dev,
518 struct device_attribute *attr,
519 const char *buf, size_t count)
521 struct vcc_port *port;
526 port = dev_get_drvdata(dev);
530 spin_lock_irqsave(&port->lock, flags);
532 if (sscanf(buf, "%ud", &brk) != 1 || brk != 1)
534 else if (vcc_send_ctl(port, VCC_CTL_BREAK) < 0)
537 spin_unlock_irqrestore(&port->lock, flags);
542 static DEVICE_ATTR(domain, 0400, vcc_sysfs_domain_show, NULL);
543 static DEVICE_ATTR(break, 0200, NULL, vcc_sysfs_break_store);
545 static struct attribute *vcc_sysfs_entries[] = {
546 &dev_attr_domain.attr,
547 &dev_attr_break.attr,
551 static struct attribute_group vcc_attribute_group = {
553 .attrs = vcc_sysfs_entries,
557 * vcc_probe() - Initialize VCC port
558 * @vdev: Pointer to VIO device of the new VCC port
561 * Initializes a VCC port to receive serial console data from
562 * the guest domain. Sets up a TTY end point on the control
563 * domain. Sets up VIO/LDC link between the guest & control
566 * Return: status of the probe
568 static int vcc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
570 struct mdesc_handle *hp;
571 struct vcc_port *port;
578 vccdbg("VCC: name=%s\n", dev_name(&vdev->dev));
580 if (!vcc_tty_driver) {
581 pr_err("VCC: TTY driver not registered\n");
585 port = kzalloc(sizeof(struct vcc_port), GFP_KERNEL);
589 name = kstrdup(dev_name(&vdev->dev), GFP_KERNEL);
591 rv = vio_driver_init(&port->vio, vdev, VDEV_CONSOLE_CON, vcc_versions,
592 ARRAY_SIZE(vcc_versions), NULL, name);
596 port->vio.debug = vcc_dbg_vio;
597 vcc_ldc_cfg.debug = vcc_dbg_ldc;
599 rv = vio_ldc_alloc(&port->vio, &vcc_ldc_cfg, port);
603 spin_lock_init(&port->lock);
605 port->index = vcc_table_add(port);
606 if (port->index == -1) {
607 pr_err("VCC: no more TTY indices left for allocation\n");
611 /* Register the device using VCC table index as TTY index */
612 dev = tty_register_device(vcc_tty_driver, port->index, &vdev->dev);
620 node = vio_vdev_node(hp, vdev);
621 if (node == MDESC_NODE_NULL) {
627 domain = mdesc_get_property(hp, node, "vcc-domain-name", NULL);
633 port->domain = kstrdup(domain, GFP_KERNEL);
637 rv = sysfs_create_group(&vdev->dev.kobj, &vcc_attribute_group);
641 timer_setup(&port->rx_timer, vcc_rx_timer, 0);
642 timer_setup(&port->tx_timer, vcc_tx_timer, 0);
644 dev_set_drvdata(&vdev->dev, port);
646 /* It's possible to receive IRQs in the middle of vio_port_up. Disable
647 * IRQs until the port is up.
649 disable_irq_nosync(vdev->rx_irq);
650 vio_port_up(&port->vio);
651 enable_irq(vdev->rx_irq);
658 tty_unregister_device(vcc_tty_driver, port->index);
660 vcc_table_remove(port->index);
662 vio_ldc_free(&port->vio);
671 * vcc_remove() - Terminate a VCC port
672 * @vdev: Pointer to VIO device of the VCC port
674 * Terminates a VCC port. Sets up the teardown of TTY and
675 * VIO/LDC link between guest and primary domains.
677 * Return: status of removal
679 static int vcc_remove(struct vio_dev *vdev)
681 struct vcc_port *port = dev_get_drvdata(&vdev->dev);
686 del_timer_sync(&port->rx_timer);
687 del_timer_sync(&port->tx_timer);
689 /* If there's a process with the device open, do a synchronous
690 * hangup of the TTY. This *may* cause the process to call close
691 * asynchronously, but it's not guaranteed.
694 tty_vhangup(port->tty);
696 /* Get exclusive reference to VCC, ensures that there are no other
697 * clients to this port
699 port = vcc_get(port->index, true);
704 tty_unregister_device(vcc_tty_driver, port->index);
706 del_timer_sync(&port->vio.timer);
707 vio_ldc_free(&port->vio);
708 sysfs_remove_group(&vdev->dev.kobj, &vcc_attribute_group);
709 dev_set_drvdata(&vdev->dev, NULL);
711 port->removed = true;
714 vcc_table_remove(port->index);
716 kfree(port->vio.name);
724 static const struct vio_device_id vcc_match[] = {
730 MODULE_DEVICE_TABLE(vio, vcc_match);
732 static struct vio_driver vcc_driver = {
733 .id_table = vcc_match,
735 .remove = vcc_remove,
739 static int vcc_open(struct tty_struct *tty, struct file *vcc_file)
741 struct vcc_port *port;
743 if (unlikely(!tty)) {
744 pr_err("VCC: open: Invalid TTY handle\n");
751 port = vcc_get_ne(tty->index);
752 if (unlikely(!port)) {
753 pr_err("VCC: open: Failed to find VCC port\n");
757 if (unlikely(!port->vio.lp)) {
758 pr_err("VCC: open: LDC channel not configured\n");
759 vcc_put(port, false);
762 vccdbgl(port->vio.lp);
764 vcc_put(port, false);
766 if (unlikely(!tty->port)) {
767 pr_err("VCC: open: TTY port not found\n");
771 if (unlikely(!tty->port->ops)) {
772 pr_err("VCC: open: TTY ops not defined\n");
776 return tty_port_open(tty->port, tty, vcc_file);
779 static void vcc_close(struct tty_struct *tty, struct file *vcc_file)
781 if (unlikely(!tty)) {
782 pr_err("VCC: close: Invalid TTY handle\n");
786 if (unlikely(tty->count > 1))
789 if (unlikely(!tty->port)) {
790 pr_err("VCC: close: TTY port not found\n");
794 tty_port_close(tty->port, tty, vcc_file);
797 static void vcc_ldc_hup(struct vcc_port *port)
801 spin_lock_irqsave(&port->lock, flags);
803 if (vcc_send_ctl(port, VCC_CTL_HUP) < 0)
806 spin_unlock_irqrestore(&port->lock, flags);
809 static void vcc_hangup(struct tty_struct *tty)
811 struct vcc_port *port;
813 if (unlikely(!tty)) {
814 pr_err("VCC: hangup: Invalid TTY handle\n");
818 port = vcc_get_ne(tty->index);
819 if (unlikely(!port)) {
820 pr_err("VCC: hangup: Failed to find VCC port\n");
824 if (unlikely(!tty->port)) {
825 pr_err("VCC: hangup: TTY port not found\n");
826 vcc_put(port, false);
832 vcc_put(port, false);
834 tty_port_hangup(tty->port);
837 static int vcc_write(struct tty_struct *tty, const unsigned char *buf,
840 struct vcc_port *port;
847 if (unlikely(!tty)) {
848 pr_err("VCC: write: Invalid TTY handle\n");
852 port = vcc_get_ne(tty->index);
853 if (unlikely(!port)) {
854 pr_err("VCC: write: Failed to find VCC port");
858 spin_lock_irqsave(&port->lock, flags);
861 pkt->tag.type = VIO_TYPE_DATA;
864 /* Minimum of data to write and space available */
865 tosend = min(count, (VCC_BUFF_LEN - port->chars_in_buffer));
870 memcpy(&pkt->data[port->chars_in_buffer], &buf[total_sent],
872 port->chars_in_buffer += tosend;
873 pkt->tag.stype = tosend;
875 vccdbg("TAG [%02x:%02x:%04x:%08x]\n", pkt->tag.type,
876 pkt->tag.stype, pkt->tag.stype_env, pkt->tag.sid);
877 vccdbg("DATA [%s]\n", pkt->data);
878 vccdbgl(port->vio.lp);
880 /* Since we know we have enough room in VCC buffer for tosend
881 * we record that it was sent regardless of whether the
882 * hypervisor actually took it because we have it buffered.
884 rv = ldc_write(port->vio.lp, pkt, (VIO_TAG_SIZE + tosend));
885 vccdbg("VCC: write: ldc_write(%d)=%d\n",
886 (VIO_TAG_SIZE + tosend), rv);
888 total_sent += tosend;
895 port->chars_in_buffer = 0;
898 spin_unlock_irqrestore(&port->lock, flags);
900 vcc_put(port, false);
902 vccdbg("VCC: write: total=%d rv=%d", total_sent, rv);
904 return total_sent ? total_sent : rv;
907 static int vcc_write_room(struct tty_struct *tty)
909 struct vcc_port *port;
912 if (unlikely(!tty)) {
913 pr_err("VCC: write_room: Invalid TTY handle\n");
917 port = vcc_get_ne(tty->index);
918 if (unlikely(!port)) {
919 pr_err("VCC: write_room: Failed to find VCC port\n");
923 num = VCC_BUFF_LEN - port->chars_in_buffer;
925 vcc_put(port, false);
930 static int vcc_chars_in_buffer(struct tty_struct *tty)
932 struct vcc_port *port;
935 if (unlikely(!tty)) {
936 pr_err("VCC: chars_in_buffer: Invalid TTY handle\n");
940 port = vcc_get_ne(tty->index);
941 if (unlikely(!port)) {
942 pr_err("VCC: chars_in_buffer: Failed to find VCC port\n");
946 num = port->chars_in_buffer;
948 vcc_put(port, false);
953 static int vcc_break_ctl(struct tty_struct *tty, int state)
955 struct vcc_port *port;
958 if (unlikely(!tty)) {
959 pr_err("VCC: break_ctl: Invalid TTY handle\n");
963 port = vcc_get_ne(tty->index);
964 if (unlikely(!port)) {
965 pr_err("VCC: break_ctl: Failed to find VCC port\n");
971 vcc_put(port, false);
975 spin_lock_irqsave(&port->lock, flags);
977 if (vcc_send_ctl(port, VCC_CTL_BREAK) < 0)
980 spin_unlock_irqrestore(&port->lock, flags);
982 vcc_put(port, false);
987 static int vcc_install(struct tty_driver *driver, struct tty_struct *tty)
989 struct vcc_port *port_vcc;
990 struct tty_port *port_tty;
993 if (unlikely(!tty)) {
994 pr_err("VCC: install: Invalid TTY handle\n");
998 if (tty->index >= VCC_MAX_PORTS)
1001 ret = tty_standard_install(driver, tty);
1005 port_tty = kzalloc(sizeof(struct tty_port), GFP_KERNEL);
1009 port_vcc = vcc_get(tty->index, true);
1011 pr_err("VCC: install: Failed to find VCC port\n");
1017 tty_port_init(port_tty);
1018 port_tty->ops = &vcc_port_ops;
1019 tty->port = port_tty;
1021 port_vcc->tty = tty;
1023 vcc_put(port_vcc, true);
1028 static void vcc_cleanup(struct tty_struct *tty)
1030 struct vcc_port *port;
1032 if (unlikely(!tty)) {
1033 pr_err("VCC: cleanup: Invalid TTY handle\n");
1037 port = vcc_get(tty->index, true);
1041 if (port->removed) {
1042 vcc_table_remove(tty->index);
1043 kfree(port->vio.name);
1044 kfree(port->domain);
1047 vcc_put(port, true);
1051 tty_port_destroy(tty->port);
1056 static const struct tty_operations vcc_ops = {
1059 .hangup = vcc_hangup,
1061 .write_room = vcc_write_room,
1062 .chars_in_buffer = vcc_chars_in_buffer,
1063 .break_ctl = vcc_break_ctl,
1064 .install = vcc_install,
1065 .cleanup = vcc_cleanup,
1068 #define VCC_TTY_FLAGS (TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_REAL_RAW)
1070 static int vcc_tty_init(void)
1074 pr_info("VCC: %s\n", version);
1076 vcc_tty_driver = tty_alloc_driver(VCC_MAX_PORTS, VCC_TTY_FLAGS);
1077 if (IS_ERR(vcc_tty_driver)) {
1078 pr_err("VCC: TTY driver alloc failed\n");
1079 return PTR_ERR(vcc_tty_driver);
1082 vcc_tty_driver->driver_name = vcc_driver_name;
1083 vcc_tty_driver->name = vcc_device_node;
1085 vcc_tty_driver->minor_start = VCC_MINOR_START;
1086 vcc_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;
1087 vcc_tty_driver->init_termios = vcc_tty_termios;
1089 tty_set_operations(vcc_tty_driver, &vcc_ops);
1091 rv = tty_register_driver(vcc_tty_driver);
1093 pr_err("VCC: TTY driver registration failed\n");
1094 put_tty_driver(vcc_tty_driver);
1095 vcc_tty_driver = NULL;
1099 vccdbg("VCC: TTY driver registered\n");
1104 static void vcc_tty_exit(void)
1106 tty_unregister_driver(vcc_tty_driver);
1107 put_tty_driver(vcc_tty_driver);
1108 vccdbg("VCC: TTY driver unregistered\n");
1110 vcc_tty_driver = NULL;
1113 static int __init vcc_init(void)
1117 rv = vcc_tty_init();
1119 pr_err("VCC: TTY init failed\n");
1123 rv = vio_register_driver(&vcc_driver);
1125 pr_err("VCC: VIO driver registration failed\n");
1128 vccdbg("VCC: VIO driver registered successfully\n");
1134 static void __exit vcc_exit(void)
1136 vio_unregister_driver(&vcc_driver);
1137 vccdbg("VCC: VIO driver unregistered\n");
1139 vccdbg("VCC: TTY driver unregistered\n");
1142 module_init(vcc_init);
1143 module_exit(vcc_exit);