xref: /openbmc/u-boot/include/video_console.h (revision baefb63a)
1 /*
2  * Copyright (c) 2015 Google, Inc
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #ifndef __video_console_h
8 #define __video_console_h
9 
10 #define VID_FRAC_DIV	256
11 
12 #define VID_TO_PIXEL(x)	((x) / VID_FRAC_DIV)
13 #define VID_TO_POS(x)	((x) * VID_FRAC_DIV)
14 
15 /**
16  * struct vidconsole_priv - uclass-private data about a console device
17  *
18  * Drivers must set up @rows, @cols, @x_charsize, @y_charsize in their probe()
19  * method. Drivers may set up @xstart_frac if desired.
20  *
21  * @sdev:	stdio device, acting as an output sink
22  * @xcur_frac:	Current X position, in fractional units (VID_TO_POS(x))
23  * @curr_row:	Current Y position in pixels (0=top)
24  * @rows:	Number of text rows
25  * @cols:	Number of text columns
26  * @x_charsize:	Character width in pixels
27  * @y_charsize:	Character height in pixels
28  * @tab_width_frac:	Tab width in fractional units
29  * @xsize_frac:	Width of the display in fractional units
30  * @xstart_frac:	Left margin for the text console in fractional units
31  * @last_ch:	Last character written to the text console on this line
32  * @escape:	TRUE if currently accumulating an ANSI escape sequence
33  * @escape_len:	Length of accumulated escape sequence so far
34  * @escape_buf:	Buffer to accumulate escape sequence
35  */
36 struct vidconsole_priv {
37 	struct stdio_dev sdev;
38 	int xcur_frac;
39 	int ycur;
40 	int rows;
41 	int cols;
42 	int x_charsize;
43 	int y_charsize;
44 	int tab_width_frac;
45 	int xsize_frac;
46 	int xstart_frac;
47 	int last_ch;
48 	/*
49 	 * ANSI escape sequences are accumulated character by character,
50 	 * starting after the ESC char (0x1b) until the entire sequence
51 	 * is consumed at which point it is acted upon.
52 	 */
53 	int escape;
54 	int escape_len;
55 	char escape_buf[32];
56 };
57 
58 /**
59  * struct vidconsole_ops - Video console operations
60  *
61  * These operations work on either an absolute console position (measured
62  * in pixels) or a text row number (measured in rows, where each row consists
63  * of an entire line of text - typically 16 pixels).
64  */
65 struct vidconsole_ops {
66 	/**
67 	 * putc_xy() - write a single character to a position
68 	 *
69 	 * @dev:	Device to write to
70 	 * @x_frac:	Fractional pixel X position (0=left-most pixel) which
71 	 *		is the X position multipled by VID_FRAC_DIV.
72 	 * @y:		Pixel Y position (0=top-most pixel)
73 	 * @ch:		Character to write
74 	 * @return number of fractional pixels that the cursor should move,
75 	 * if all is OK, -EAGAIN if we ran out of space on this line, other -ve
76 	 * on error
77 	 */
78 	int (*putc_xy)(struct udevice *dev, uint x_frac, uint y, char ch);
79 
80 	/**
81 	 * move_rows() - Move text rows from one place to another
82 	 *
83 	 * @dev:	Device to adjust
84 	 * @rowdst:	Destination text row (0=top)
85 	 * @rowsrc:	Source start text row
86 	 * @count:	Number of text rows to move
87 	 * @return 0 if OK, -ve on error
88 	 */
89 	int (*move_rows)(struct udevice *dev, uint rowdst, uint rowsrc,
90 			  uint count);
91 
92 	/**
93 	 * set_row() - Set the colour of a text row
94 	 *
95 	 * Every pixel contained within the text row is adjusted
96 	 *
97 	 * @dev:	Device to adjust
98 	 * @row:	Text row to adjust (0=top)
99 	 * @clr:	Raw colour (pixel value) to write to each pixel
100 	 * @return 0 if OK, -ve on error
101 	 */
102 	int (*set_row)(struct udevice *dev, uint row, int clr);
103 
104 	/**
105 	 * entry_start() - Indicate that text entry is starting afresh
106 	 *
107 	 * Consoles which use proportional fonts need to track the position of
108 	 * each character output so that backspace will return to the correct
109 	 * place. This method signals to the console driver that a new entry
110 	 * line is being start (e.g. the user pressed return to start a new
111 	 * command). The driver can use this signal to empty its list of
112 	 * positions.
113 	 */
114 	int (*entry_start)(struct udevice *dev);
115 
116 	/**
117 	 * backspace() - Handle erasing the last character
118 	 *
119 	 * With proportional fonts the vidconsole uclass cannot itself erase
120 	 * the previous character. This optional method will be called when
121 	 * a backspace is needed. The driver should erase the previous
122 	 * character and update the cursor position (xcur_frac, ycur) to the
123 	 * start of the previous character.
124 	 *
125 	 * If not implement, default behaviour will work for fixed-width
126 	 * characters.
127 	 */
128 	int (*backspace)(struct udevice *dev);
129 };
130 
131 /* Get a pointer to the driver operations for a video console device */
132 #define vidconsole_get_ops(dev)  ((struct vidconsole_ops *)(dev)->driver->ops)
133 
134 /**
135  * vidconsole_putc_xy() - write a single character to a position
136  *
137  * @dev:	Device to write to
138  * @x_frac:	Fractional pixel X position (0=left-most pixel) which
139  *		is the X position multipled by VID_FRAC_DIV.
140  * @y:		Pixel Y position (0=top-most pixel)
141  * @ch:		Character to write
142  * @return number of fractional pixels that the cursor should move,
143  * if all is OK, -EAGAIN if we ran out of space on this line, other -ve
144  * on error
145  */
146 int vidconsole_putc_xy(struct udevice *dev, uint x, uint y, char ch);
147 
148 /**
149  * vidconsole_move_rows() - Move text rows from one place to another
150  *
151  * @dev:	Device to adjust
152  * @rowdst:	Destination text row (0=top)
153  * @rowsrc:	Source start text row
154  * @count:	Number of text rows to move
155  * @return 0 if OK, -ve on error
156  */
157 int vidconsole_move_rows(struct udevice *dev, uint rowdst, uint rowsrc,
158 			 uint count);
159 
160 /**
161  * vidconsole_set_row() - Set the colour of a text row
162  *
163  * Every pixel contained within the text row is adjusted
164  *
165  * @dev:	Device to adjust
166  * @row:	Text row to adjust (0=top)
167  * @clr:	Raw colour (pixel value) to write to each pixel
168  * @return 0 if OK, -ve on error
169  */
170 int vidconsole_set_row(struct udevice *dev, uint row, int clr);
171 
172 /**
173  * vidconsole_put_char() - Output a character to the current console position
174  *
175  * Outputs a character to the console and advances the cursor. This function
176  * handles wrapping to new lines and scrolling the console. Special
177  * characters are handled also: \n, \r, \b and \t.
178  *
179  * The device always starts with the cursor at position 0,0 (top left). It
180  * can be adjusted manually using vidconsole_position_cursor().
181  *
182  * @dev:	Device to adjust
183  * @ch:		Character to write
184  * @return 0 if OK, -ve on error
185  */
186 int vidconsole_put_char(struct udevice *dev, char ch);
187 
188 /**
189  * vidconsole_position_cursor() - Move the text cursor
190  *
191  * @dev:	Device to adjust
192  * @col:	New cursor text column
193  * @row:	New cursor text row
194  * @return 0 if OK, -ve on error
195  */
196 void vidconsole_position_cursor(struct udevice *dev, unsigned col,
197 				unsigned row);
198 
199 #endif
200