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
48 struct 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 */
68 struct 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
78 /* Register a vterm and a slot index for use as a console (console_init) */
79 extern int hvc_instantiate(uint32_t vtermno, int index,
80 const struct hv_ops *ops);
81
82 /* register a vterm for hvc tty operation (module_init or hotplug add) */
83 extern struct hvc_struct * hvc_alloc(uint32_t vtermno, int data,
84 const struct hv_ops *ops, int outbuf_size);
85 /* remove a vterm from hvc tty operation (module_exit or hotplug remove) */
86 extern int hvc_remove(struct hvc_struct *hp);
87
88 /* data available */
89 int hvc_poll(struct hvc_struct *hp);
90 void hvc_kick(void);
91
92 /* Resize hvc tty terminal window */
93 extern void __hvc_resize(struct hvc_struct *hp, struct winsize ws);
94
hvc_resize(struct hvc_struct * hp,struct winsize ws)95 static inline void hvc_resize(struct hvc_struct *hp, struct winsize ws)
96 {
97 unsigned long flags;
98
99 spin_lock_irqsave(&hp->lock, flags);
100 __hvc_resize(hp, ws);
101 spin_unlock_irqrestore(&hp->lock, flags);
102 }
103
104 /* default notifier for irq based notification */
105 extern int notifier_add_irq(struct hvc_struct *hp, int data);
106 extern void notifier_del_irq(struct hvc_struct *hp, int data);
107 extern void notifier_hangup_irq(struct hvc_struct *hp, int data);
108
109
110 #if defined(CONFIG_XMON) && defined(CONFIG_SMP)
111 #include <asm/xmon.h>
112 #else
cpus_are_in_xmon(void)113 static inline int cpus_are_in_xmon(void)
114 {
115 return 0;
116 }
117 #endif
118
119 #endif // HVC_CONSOLE_H
120