1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * hvc_console.h 4 * Copyright (C) 2005 IBM Corporation 5 * 6 * Author(s): 7 * Ryan S. Arnold <rsa@us.ibm.com> 8 * 9 * hvc_console header information: 10 * moved here from arch/powerpc/include/asm/hvconsole.h 11 * and drivers/char/hvc_console.c 12 * 13 * This program is free software; you can redistribute it and/or modify 14 * it under the terms of the GNU General Public License as published by 15 * the Free Software Foundation; either version 2 of the License, or 16 * (at your option) any later version. 17 * 18 * This program is distributed in the hope that it will be useful, 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 21 * GNU General Public License for more details. 22 * 23 * You should have received a copy of the GNU General Public License 24 * along with this program; if not, write to the Free Software 25 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 26 */ 27 28 #ifndef HVC_CONSOLE_H 29 #define HVC_CONSOLE_H 30 #include <linux/kref.h> 31 #include <linux/tty.h> 32 #include <linux/spinlock.h> 33 34 /* 35 * This is the max number of console adapters that can/will be found as 36 * console devices on first stage console init. Any number beyond this range 37 * can't be used as a console device but is still a valid tty device. 38 */ 39 #define MAX_NR_HVC_CONSOLES 16 40 41 /* 42 * The Linux TTY code does not support dynamic addition of tty derived devices 43 * so we need to know how many tty devices we might need when space is allocated 44 * for the tty device. Since this driver supports hotplug of vty adapters we 45 * need to make sure we have enough allocated. 46 */ 47 #define HVC_ALLOC_TTY_ADAPTERS 8 48 49 struct hvc_struct { 50 struct tty_port port; 51 spinlock_t lock; 52 int index; 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 unsigned long flags; 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 /* 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 /* Callbacks to handle tty ports */ 82 void (*dtr_rts)(struct hvc_struct *hp, int raise); 83 }; 84 85 /* Register a vterm and a slot index for use as a console (console_init) */ 86 extern int hvc_instantiate(uint32_t vtermno, int index, 87 const struct hv_ops *ops); 88 89 /* register a vterm for hvc tty operation (module_init or hotplug add) */ 90 extern struct hvc_struct * hvc_alloc(uint32_t vtermno, int data, 91 const struct hv_ops *ops, int outbuf_size); 92 /* remove a vterm from hvc tty operation (module_exit or hotplug remove) */ 93 extern int hvc_remove(struct hvc_struct *hp); 94 95 /* data available */ 96 int hvc_poll(struct hvc_struct *hp); 97 void hvc_kick(void); 98 99 /* Resize hvc tty terminal window */ 100 extern void __hvc_resize(struct hvc_struct *hp, struct winsize ws); 101 102 static inline void hvc_resize(struct hvc_struct *hp, struct winsize ws) 103 { 104 unsigned long flags; 105 106 spin_lock_irqsave(&hp->lock, flags); 107 __hvc_resize(hp, ws); 108 spin_unlock_irqrestore(&hp->lock, flags); 109 } 110 111 /* default notifier for irq based notification */ 112 extern int notifier_add_irq(struct hvc_struct *hp, int data); 113 extern void notifier_del_irq(struct hvc_struct *hp, int data); 114 extern void notifier_hangup_irq(struct hvc_struct *hp, int data); 115 116 117 #if defined(CONFIG_XMON) && defined(CONFIG_SMP) 118 #include <asm/xmon.h> 119 #else 120 static inline int cpus_are_in_xmon(void) 121 { 122 return 0; 123 } 124 #endif 125 126 #endif // HVC_CONSOLE_H 127