1/*
2 * hvc_console.h
3 * Copyright (C) 2005 IBM Corporation
4 *
5 * Author(s):
6 * 	Ryan S. Arnold <rsa@us.ibm.com>
7 *
8 * hvc_console header information:
9 *      moved here from arch/powerpc/include/asm/hvconsole.h
10 *      and drivers/char/hvc_console.c
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
25 */
26
27#ifndef HVC_CONSOLE_H
28#define HVC_CONSOLE_H
29#include <linux/kref.h>
30#include <linux/tty.h>
31#include <linux/spinlock.h>
32
33/*
34 * This is the max number of console adapters that can/will be found as
35 * console devices on first stage console init.  Any number beyond this range
36 * can't be used as a console device but is still a valid tty device.
37 */
38#define MAX_NR_HVC_CONSOLES	16
39
40/*
41 * The Linux TTY code does not support dynamic addition of tty derived devices
42 * so we need to know how many tty devices we might need when space is allocated
43 * for the tty device.  Since this driver supports hotplug of vty adapters we
44 * need to make sure we have enough allocated.
45 */
46#define HVC_ALLOC_TTY_ADAPTERS	8
47
48struct hvc_struct {
49	spinlock_t lock;
50	int index;
51	struct tty_struct *tty;
52	int count;
53	int do_wakeup;
54	char *outbuf;
55	int outbuf_size;
56	int n_outbuf;
57	uint32_t vtermno;
58	const struct hv_ops *ops;
59	int irq_requested;
60	int data;
61	struct winsize ws;
62	struct work_struct tty_resize;
63	struct list_head next;
64	struct kref kref; /* ref count & hvc_struct lifetime */
65};
66
67/* implemented by a low level driver */
68struct hv_ops {
69	int (*get_chars)(uint32_t vtermno, char *buf, int count);
70	int (*put_chars)(uint32_t vtermno, const char *buf, int count);
71
72	/* Callbacks for notification. Called in open, close and hangup */
73	int (*notifier_add)(struct hvc_struct *hp, int irq);
74	void (*notifier_del)(struct hvc_struct *hp, int irq);
75	void (*notifier_hangup)(struct hvc_struct *hp, int irq);
76
77	/* tiocmget/set implementation */
78	int (*tiocmget)(struct hvc_struct *hp);
79	int (*tiocmset)(struct hvc_struct *hp, unsigned int set, unsigned int clear);
80};
81
82/* Register a vterm and a slot index for use as a console (console_init) */
83extern int hvc_instantiate(uint32_t vtermno, int index,
84			   const struct hv_ops *ops);
85
86/* register a vterm for hvc tty operation (module_init or hotplug add) */
87extern struct hvc_struct * hvc_alloc(uint32_t vtermno, int data,
88				     const struct hv_ops *ops, int outbuf_size);
89/* remove a vterm from hvc tty operation (module_exit or hotplug remove) */
90extern int hvc_remove(struct hvc_struct *hp);
91
92/* data available */
93int hvc_poll(struct hvc_struct *hp);
94void hvc_kick(void);
95
96/* Resize hvc tty terminal window */
97extern void __hvc_resize(struct hvc_struct *hp, struct winsize ws);
98
99static inline void hvc_resize(struct hvc_struct *hp, struct winsize ws)
100{
101	unsigned long flags;
102
103	spin_lock_irqsave(&hp->lock, flags);
104	__hvc_resize(hp, ws);
105	spin_unlock_irqrestore(&hp->lock, flags);
106}
107
108/* default notifier for irq based notification */
109extern int notifier_add_irq(struct hvc_struct *hp, int data);
110extern void notifier_del_irq(struct hvc_struct *hp, int data);
111extern void notifier_hangup_irq(struct hvc_struct *hp, int data);
112
113
114#if defined(CONFIG_XMON) && defined(CONFIG_SMP)
115#include <asm/xmon.h>
116#else
117static inline int cpus_are_in_xmon(void)
118{
119	return 0;
120}
121#endif
122
123#endif // HVC_CONSOLE_H
124