xref: /linux-6.15/include/linux/console.h (revision 6fbd8569)
1 /*
2  *  linux/include/linux/console.h
3  *
4  *  Copyright (C) 1993        Hamish Macdonald
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file COPYING in the main directory of this archive
8  * for more details.
9  *
10  * Changed:
11  * 10-Mar-94: Arno Griffioen: Conversion for vt100 emulator port from PC LINUX
12  */
13 
14 #ifndef _LINUX_CONSOLE_H_
15 #define _LINUX_CONSOLE_H_ 1
16 
17 #include <linux/types.h>
18 
19 struct vc_data;
20 struct console_font_op;
21 struct console_font;
22 struct module;
23 struct tty_struct;
24 struct notifier_block;
25 
26 /*
27  * this is what the terminal answers to a ESC-Z or csi0c query.
28  */
29 #define VT100ID "\033[?1;2c"
30 #define VT102ID "\033[?6c"
31 
32 enum con_scroll {
33 	SM_UP,
34 	SM_DOWN,
35 };
36 
37 /**
38  * struct consw - callbacks for consoles
39  *
40  * @con_scroll: move lines from @top to @bottom in direction @dir by @lines.
41  *		Return true if no generic handling should be done.
42  *		Invoked by csi_M and printing to the console.
43  * @con_set_palette: sets the palette of the console to @table (optional)
44  * @con_scrolldelta: the contents of the console should be scrolled by @lines.
45  *		     Invoked by user. (optional)
46  */
47 struct consw {
48 	struct module *owner;
49 	const char *(*con_startup)(void);
50 	void	(*con_init)(struct vc_data *vc, int init);
51 	void	(*con_deinit)(struct vc_data *vc);
52 	void	(*con_clear)(struct vc_data *vc, int sy, int sx, int height,
53 			int width);
54 	void	(*con_putc)(struct vc_data *vc, int c, int ypos, int xpos);
55 	void	(*con_putcs)(struct vc_data *vc, const unsigned short *s,
56 			int count, int ypos, int xpos);
57 	void	(*con_cursor)(struct vc_data *vc, int mode);
58 	bool	(*con_scroll)(struct vc_data *vc, unsigned int top,
59 			unsigned int bottom, enum con_scroll dir,
60 			unsigned int lines);
61 	int	(*con_switch)(struct vc_data *vc);
62 	int	(*con_blank)(struct vc_data *vc, int blank, int mode_switch);
63 	int	(*con_font_set)(struct vc_data *vc, struct console_font *font,
64 			unsigned int flags);
65 	int	(*con_font_get)(struct vc_data *vc, struct console_font *font);
66 	int	(*con_font_default)(struct vc_data *vc,
67 			struct console_font *font, char *name);
68 	int	(*con_font_copy)(struct vc_data *vc, int con);
69 	int     (*con_resize)(struct vc_data *vc, unsigned int width,
70 			unsigned int height, unsigned int user);
71 	void	(*con_set_palette)(struct vc_data *vc,
72 			const unsigned char *table);
73 	void	(*con_scrolldelta)(struct vc_data *vc, int lines);
74 	int	(*con_set_origin)(struct vc_data *vc);
75 	void	(*con_save_screen)(struct vc_data *vc);
76 	u8	(*con_build_attr)(struct vc_data *vc, u8 color, u8 intensity,
77 			u8 blink, u8 underline, u8 reverse, u8 italic);
78 	void	(*con_invert_region)(struct vc_data *vc, u16 *p, int count);
79 	u16    *(*con_screen_pos)(struct vc_data *vc, int offset);
80 	unsigned long (*con_getxy)(struct vc_data *vc, unsigned long position,
81 			int *px, int *py);
82 	/*
83 	 * Flush the video console driver's scrollback buffer
84 	 */
85 	void	(*con_flush_scrollback)(struct vc_data *vc);
86 	/*
87 	 * Prepare the console for the debugger.  This includes, but is not
88 	 * limited to, unblanking the console, loading an appropriate
89 	 * palette, and allowing debugger generated output.
90 	 */
91 	int	(*con_debug_enter)(struct vc_data *vc);
92 	/*
93 	 * Restore the console to its pre-debug state as closely as possible.
94 	 */
95 	int	(*con_debug_leave)(struct vc_data *vc);
96 };
97 
98 extern const struct consw *conswitchp;
99 
100 extern const struct consw dummy_con;	/* dummy console buffer */
101 extern const struct consw vga_con;	/* VGA text console */
102 extern const struct consw newport_con;	/* SGI Newport console  */
103 extern const struct consw prom_con;	/* SPARC PROM console */
104 
105 int con_is_bound(const struct consw *csw);
106 int do_unregister_con_driver(const struct consw *csw);
107 int do_take_over_console(const struct consw *sw, int first, int last, int deflt);
108 void give_up_console(const struct consw *sw);
109 #ifdef CONFIG_HW_CONSOLE
110 int con_debug_enter(struct vc_data *vc);
111 int con_debug_leave(void);
112 #else
113 static inline int con_debug_enter(struct vc_data *vc)
114 {
115 	return 0;
116 }
117 static inline int con_debug_leave(void)
118 {
119 	return 0;
120 }
121 #endif
122 
123 /* cursor */
124 #define CM_DRAW     (1)
125 #define CM_ERASE    (2)
126 #define CM_MOVE     (3)
127 
128 /*
129  * The interface for a console, or any other device that wants to capture
130  * console messages (printer driver?)
131  *
132  * If a console driver is marked CON_BOOT then it will be auto-unregistered
133  * when the first real console is registered.  This is for early-printk drivers.
134  */
135 
136 #define CON_PRINTBUFFER	(1)
137 #define CON_CONSDEV	(2) /* Last on the command line */
138 #define CON_ENABLED	(4)
139 #define CON_BOOT	(8)
140 #define CON_ANYTIME	(16) /* Safe to call when cpu is offline */
141 #define CON_BRL		(32) /* Used for a braille device */
142 #define CON_EXTENDED	(64) /* Use the extended output format a la /dev/kmsg */
143 
144 struct console {
145 	char	name[16];
146 	void	(*write)(struct console *, const char *, unsigned);
147 	int	(*read)(struct console *, char *, unsigned);
148 	struct tty_driver *(*device)(struct console *, int *);
149 	void	(*unblank)(void);
150 	int	(*setup)(struct console *, char *);
151 	int	(*match)(struct console *, char *name, int idx, char *options);
152 	short	flags;
153 	short	index;
154 	int	cflag;
155 	void	*data;
156 	struct	 console *next;
157 };
158 
159 /*
160  * for_each_console() allows you to iterate on each console
161  */
162 #define for_each_console(con) \
163 	for (con = console_drivers; con != NULL; con = con->next)
164 
165 extern int console_set_on_cmdline;
166 extern struct console *early_console;
167 
168 extern int add_preferred_console(char *name, int idx, char *options);
169 extern void register_console(struct console *);
170 extern int unregister_console(struct console *);
171 extern struct console *console_drivers;
172 extern void console_lock(void);
173 extern int console_trylock(void);
174 extern void console_unlock(void);
175 extern void console_conditional_schedule(void);
176 extern void console_unblank(void);
177 extern void console_flush_on_panic(void);
178 extern struct tty_driver *console_device(int *);
179 extern void console_stop(struct console *);
180 extern void console_start(struct console *);
181 extern int is_console_locked(void);
182 extern int braille_register_console(struct console *, int index,
183 		char *console_options, char *braille_options);
184 extern int braille_unregister_console(struct console *);
185 #ifdef CONFIG_TTY
186 extern void console_sysfs_notify(void);
187 #else
188 static inline void console_sysfs_notify(void)
189 { }
190 #endif
191 extern bool console_suspend_enabled;
192 
193 /* Suspend and resume console messages over PM events */
194 extern void suspend_console(void);
195 extern void resume_console(void);
196 
197 int mda_console_init(void);
198 void prom_con_init(void);
199 
200 void vcs_make_sysfs(int index);
201 void vcs_remove_sysfs(int index);
202 
203 /* Some debug stub to catch some of the obvious races in the VT code */
204 #if 1
205 #define WARN_CONSOLE_UNLOCKED()	WARN_ON(!is_console_locked() && !oops_in_progress)
206 #else
207 #define WARN_CONSOLE_UNLOCKED()
208 #endif
209 
210 /* VESA Blanking Levels */
211 #define VESA_NO_BLANKING        0
212 #define VESA_VSYNC_SUSPEND      1
213 #define VESA_HSYNC_SUSPEND      2
214 #define VESA_POWERDOWN          3
215 
216 #ifdef CONFIG_VGA_CONSOLE
217 extern bool vgacon_text_force(void);
218 #else
219 static inline bool vgacon_text_force(void) { return false; }
220 #endif
221 
222 extern void console_init(void);
223 
224 /* For deferred console takeover */
225 void dummycon_register_output_notifier(struct notifier_block *nb);
226 void dummycon_unregister_output_notifier(struct notifier_block *nb);
227 
228 #endif /* _LINUX_CONSOLE_H */
229