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/atomic.h>
18 #include <linux/types.h>
19 
20 struct vc_data;
21 struct console_font_op;
22 struct console_font;
23 struct module;
24 struct tty_struct;
25 struct notifier_block;
26 
27 /*
28  * this is what the terminal answers to a ESC-Z or csi0c query.
29  */
30 #define VT100ID "\033[?1;2c"
31 #define VT102ID "\033[?6c"
32 
33 enum con_scroll {
34 	SM_UP,
35 	SM_DOWN,
36 };
37 
38 /**
39  * struct consw - callbacks for consoles
40  *
41  * @con_scroll: move lines from @top to @bottom in direction @dir by @lines.
42  *		Return true if no generic handling should be done.
43  *		Invoked by csi_M and printing to the console.
44  * @con_set_palette: sets the palette of the console to @table (optional)
45  * @con_scrolldelta: the contents of the console should be scrolled by @lines.
46  *		     Invoked by user. (optional)
47  */
48 struct consw {
49 	struct module *owner;
50 	const char *(*con_startup)(void);
51 	void	(*con_init)(struct vc_data *vc, int init);
52 	void	(*con_deinit)(struct vc_data *vc);
53 	void	(*con_clear)(struct vc_data *vc, int sy, int sx, int height,
54 			int width);
55 	void	(*con_putc)(struct vc_data *vc, int c, int ypos, int xpos);
56 	void	(*con_putcs)(struct vc_data *vc, const unsigned short *s,
57 			int count, int ypos, int xpos);
58 	void	(*con_cursor)(struct vc_data *vc, int mode);
59 	bool	(*con_scroll)(struct vc_data *vc, unsigned int top,
60 			unsigned int bottom, enum con_scroll dir,
61 			unsigned int lines);
62 	int	(*con_switch)(struct vc_data *vc);
63 	int	(*con_blank)(struct vc_data *vc, int blank, int mode_switch);
64 	int	(*con_font_set)(struct vc_data *vc, struct console_font *font,
65 			unsigned int flags);
66 	int	(*con_font_get)(struct vc_data *vc, struct console_font *font);
67 	int	(*con_font_default)(struct vc_data *vc,
68 			struct console_font *font, char *name);
69 	int	(*con_font_copy)(struct vc_data *vc, int con);
70 	int     (*con_resize)(struct vc_data *vc, unsigned int width,
71 			unsigned int height, unsigned int user);
72 	void	(*con_set_palette)(struct vc_data *vc,
73 			const unsigned char *table);
74 	void	(*con_scrolldelta)(struct vc_data *vc, int lines);
75 	int	(*con_set_origin)(struct vc_data *vc);
76 	void	(*con_save_screen)(struct vc_data *vc);
77 	u8	(*con_build_attr)(struct vc_data *vc, u8 color, u8 intensity,
78 			u8 blink, u8 underline, u8 reverse, u8 italic);
79 	void	(*con_invert_region)(struct vc_data *vc, u16 *p, int count);
80 	u16    *(*con_screen_pos)(struct vc_data *vc, int offset);
81 	unsigned long (*con_getxy)(struct vc_data *vc, unsigned long position,
82 			int *px, int *py);
83 	/*
84 	 * Flush the video console driver's scrollback buffer
85 	 */
86 	void	(*con_flush_scrollback)(struct vc_data *vc);
87 	/*
88 	 * Prepare the console for the debugger.  This includes, but is not
89 	 * limited to, unblanking the console, loading an appropriate
90 	 * palette, and allowing debugger generated output.
91 	 */
92 	int	(*con_debug_enter)(struct vc_data *vc);
93 	/*
94 	 * Restore the console to its pre-debug state as closely as possible.
95 	 */
96 	int	(*con_debug_leave)(struct vc_data *vc);
97 };
98 
99 extern const struct consw *conswitchp;
100 
101 extern const struct consw dummy_con;	/* dummy console buffer */
102 extern const struct consw vga_con;	/* VGA text console */
103 extern const struct consw newport_con;	/* SGI Newport console  */
104 extern const struct consw prom_con;	/* SPARC PROM console */
105 
106 int con_is_bound(const struct consw *csw);
107 int do_unregister_con_driver(const struct consw *csw);
108 int do_take_over_console(const struct consw *sw, int first, int last, int deflt);
109 void give_up_console(const struct consw *sw);
110 #ifdef CONFIG_HW_CONSOLE
111 int con_debug_enter(struct vc_data *vc);
112 int con_debug_leave(void);
113 #else
con_debug_enter(struct vc_data * vc)114 static inline int con_debug_enter(struct vc_data *vc)
115 {
116 	return 0;
117 }
con_debug_leave(void)118 static inline int con_debug_leave(void)
119 {
120 	return 0;
121 }
122 #endif
123 
124 /* cursor */
125 #define CM_DRAW     (1)
126 #define CM_ERASE    (2)
127 #define CM_MOVE     (3)
128 
129 /*
130  * The interface for a console, or any other device that wants to capture
131  * console messages (printer driver?)
132  *
133  * If a console driver is marked CON_BOOT then it will be auto-unregistered
134  * when the first real console is registered.  This is for early-printk drivers.
135  */
136 
137 #define CON_PRINTBUFFER	(1)
138 #define CON_CONSDEV	(2) /* Last on the command line */
139 #define CON_ENABLED	(4)
140 #define CON_BOOT	(8)
141 #define CON_ANYTIME	(16) /* Safe to call when cpu is offline */
142 #define CON_BRL		(32) /* Used for a braille device */
143 #define CON_EXTENDED	(64) /* Use the extended output format a la /dev/kmsg */
144 
145 struct console {
146 	char	name[16];
147 	void	(*write)(struct console *, const char *, unsigned);
148 	int	(*read)(struct console *, char *, unsigned);
149 	struct tty_driver *(*device)(struct console *, int *);
150 	void	(*unblank)(void);
151 	int	(*setup)(struct console *, char *);
152 	int	(*match)(struct console *, char *name, int idx, char *options);
153 	short	flags;
154 	short	index;
155 	int	cflag;
156 	void	*data;
157 	struct	 console *next;
158 };
159 
160 /*
161  * for_each_console() allows you to iterate on each console
162  */
163 #define for_each_console(con) \
164 	for (con = console_drivers; con != NULL; con = con->next)
165 
166 extern int console_set_on_cmdline;
167 extern struct console *early_console;
168 
169 enum con_flush_mode {
170 	CONSOLE_FLUSH_PENDING,
171 	CONSOLE_REPLAY_ALL,
172 };
173 
174 extern int add_preferred_console(char *name, int idx, char *options);
175 extern void register_console(struct console *);
176 extern int unregister_console(struct console *);
177 extern struct console *console_drivers;
178 extern void console_lock(void);
179 extern int console_trylock(void);
180 extern void console_unlock(void);
181 extern void console_conditional_schedule(void);
182 extern void console_unblank(void);
183 extern void console_flush_on_panic(enum con_flush_mode mode);
184 extern struct tty_driver *console_device(int *);
185 extern void console_stop(struct console *);
186 extern void console_start(struct console *);
187 extern int is_console_locked(void);
188 extern int braille_register_console(struct console *, int index,
189 		char *console_options, char *braille_options);
190 extern int braille_unregister_console(struct console *);
191 #ifdef CONFIG_TTY
192 extern void console_sysfs_notify(void);
193 #else
console_sysfs_notify(void)194 static inline void console_sysfs_notify(void)
195 { }
196 #endif
197 extern bool console_suspend_enabled;
198 
199 /* Suspend and resume console messages over PM events */
200 extern void suspend_console(void);
201 extern void resume_console(void);
202 
203 int mda_console_init(void);
204 void prom_con_init(void);
205 
206 void vcs_make_sysfs(int index);
207 void vcs_remove_sysfs(int index);
208 
209 /* Some debug stub to catch some of the obvious races in the VT code */
210 #define WARN_CONSOLE_UNLOCKED()						\
211 	WARN_ON(!atomic_read(&ignore_console_lock_warning) &&		\
212 		!is_console_locked() && !oops_in_progress)
213 /*
214  * Increment ignore_console_lock_warning if you need to quiet
215  * WARN_CONSOLE_UNLOCKED() for debugging purposes.
216  */
217 extern atomic_t ignore_console_lock_warning;
218 
219 /* VESA Blanking Levels */
220 #define VESA_NO_BLANKING        0
221 #define VESA_VSYNC_SUSPEND      1
222 #define VESA_HSYNC_SUSPEND      2
223 #define VESA_POWERDOWN          3
224 
225 #ifdef CONFIG_VGA_CONSOLE
226 extern bool vgacon_text_force(void);
227 #else
vgacon_text_force(void)228 static inline bool vgacon_text_force(void) { return false; }
229 #endif
230 
231 extern void console_init(void);
232 
233 /* For deferred console takeover */
234 void dummycon_register_output_notifier(struct notifier_block *nb);
235 void dummycon_unregister_output_notifier(struct notifier_block *nb);
236 
237 #endif /* _LINUX_CONSOLE_H */
238