drivers/char/hvc_console.h

   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
  32 /*
  33  * This is the max number of console adapters that can/will be found as
  34  * console devices on first stage console init.  Any number beyond this range
  35  * can't be used as a console device but is still a valid tty device.
  36  */
  37 #define MAX_NR_HVC_CONSOLES     16
  38
  39 /*
  40  * The Linux TTY code does not support dynamic addition of tty derived devices
  41  * so we need to know how many tty devices we might need when space is allocated
  42  * for the tty device.  Since this driver supports hotplug of vty adapters we
  43  * need to make sure we have enough allocated.
  44  */
  45 #define HVC_ALLOC_TTY_ADAPTERS  8
  46
  47 struct hvc_struct {
  48         spinlock_t lock;
  49         int index;
  50         struct tty_struct *tty;
  51         unsigned int count;
  52         int do_wakeup;
  53         char *outbuf;
  54         int outbuf_size;
  55         int n_outbuf;
  56         uint32_t vtermno;
  57         struct hv_ops *ops;
  58         int irq_requested;
  59         int data;
  60         struct winsize ws;
  61         struct work_struct tty_resize;
  62         struct list_head next;
  63         struct kref kref; /* ref count & hvc_struct lifetime */
  64 };
  65
  66 /* implemented by a low level driver */
  67 struct hv_ops {
  68         int (*get_chars)(uint32_t vtermno, char *buf, int count);
  69         int (*put_chars)(uint32_t vtermno, const char *buf, int count);
  70
  71         /* Callbacks for notification. Called in open, close and hangup */
  72         int (*notifier_add)(struct hvc_struct *hp, int irq);
  73         void (*notifier_del)(struct hvc_struct *hp, int irq);
  74         void (*notifier_hangup)(struct hvc_struct *hp, int irq);
  75 };
  76
  77 /* Register a vterm and a slot index for use as a console (console_init) */
  78 extern int hvc_instantiate(uint32_t vtermno, int index, struct hv_ops *ops);
  79
  80 /* register a vterm for hvc tty operation (module_init or hotplug add) */
  81 extern struct hvc_struct * __devinit hvc_alloc(uint32_t vtermno, int data,
  82                                 struct hv_ops *ops, int outbuf_size);
  83 /* remove a vterm from hvc tty operation (module_exit or hotplug remove) */
  84 extern int hvc_remove(struct hvc_struct *hp);
  85
  86 /* data available */
  87 int hvc_poll(struct hvc_struct *hp);
  88 void hvc_kick(void);
  89
  90 /* Resize hvc tty terminal window */
  91 extern void hvc_resize(struct hvc_struct *hp, struct winsize ws);
  92
  93 /* default notifier for irq based notification */
  94 extern int notifier_add_irq(struct hvc_struct *hp, int data);
  95 extern void notifier_del_irq(struct hvc_struct *hp, int data);
  96 extern void notifier_hangup_irq(struct hvc_struct *hp, int data);
  97
  98
  99 #if defined(CONFIG_XMON) && defined(CONFIG_SMP)
 100 #include <asm/xmon.h>
 101 #else
 102 static inline int cpus_are_in_xmon(void)
 103 {
 104         return 0;
 105 }
 106 #endif
 107
 108 #endif // HVC_CONSOLE_H