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