xref: /openbmc/u-boot/include/video_console.h (revision 274bced8)
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  */
33 struct vidconsole_priv {
34 	struct stdio_dev sdev;
35 	int xcur_frac;
36 	int ycur;
37 	int rows;
38 	int cols;
39 	int x_charsize;
40 	int y_charsize;
41 	int tab_width_frac;
42 	int xsize_frac;
43 	int xstart_frac;
44 	int last_ch;
45 };
46 
47 /**
48  * struct vidconsole_ops - Video console operations
49  *
50  * These operations work on either an absolute console position (measured
51  * in pixels) or a text row number (measured in rows, where each row consists
52  * of an entire line of text - typically 16 pixels).
53  */
54 struct vidconsole_ops {
55 	/**
56 	 * putc_xy() - write a single character to a position
57 	 *
58 	 * @dev:	Device to write to
59 	 * @x_frac:	Fractional pixel X position (0=left-most pixel) which
60 	 *		is the X position multipled by VID_FRAC_DIV.
61 	 * @y:		Pixel Y position (0=top-most pixel)
62 	 * @ch:		Character to write
63 	 * @return number of fractional pixels that the cursor should move,
64 	 * if all is OK, -EAGAIN if we ran out of space on this line, other -ve
65 	 * on error
66 	 */
67 	int (*putc_xy)(struct udevice *dev, uint x_frac, uint y, char ch);
68 
69 	/**
70 	 * move_rows() - Move text rows from one place to another
71 	 *
72 	 * @dev:	Device to adjust
73 	 * @rowdst:	Destination text row (0=top)
74 	 * @rowsrc:	Source start text row
75 	 * @count:	Number of text rows to move
76 	 * @return 0 if OK, -ve on error
77 	 */
78 	int (*move_rows)(struct udevice *dev, uint rowdst, uint rowsrc,
79 			  uint count);
80 
81 	/**
82 	 * set_row() - Set the colour of a text row
83 	 *
84 	 * Every pixel contained within the text row is adjusted
85 	 *
86 	 * @dev:	Device to adjust
87 	 * @row:	Text row to adjust (0=top)
88 	 * @clr:	Raw colour (pixel value) to write to each pixel
89 	 * @return 0 if OK, -ve on error
90 	 */
91 	int (*set_row)(struct udevice *dev, uint row, int clr);
92 
93 	/**
94 	 * entry_start() - Indicate that text entry is starting afresh
95 	 *
96 	 * Consoles which use proportional fonts need to track the position of
97 	 * each character output so that backspace will return to the correct
98 	 * place. This method signals to the console driver that a new entry
99 	 * line is being start (e.g. the user pressed return to start a new
100 	 * command). The driver can use this signal to empty its list of
101 	 * positions.
102 	 */
103 	int (*entry_start)(struct udevice *dev);
104 
105 	/**
106 	 * backspace() - Handle erasing the last character
107 	 *
108 	 * With proportional fonts the vidconsole uclass cannot itself erase
109 	 * the previous character. This optional method will be called when
110 	 * a backspace is needed. The driver should erase the previous
111 	 * character and update the cursor position (xcur_frac, ycur) to the
112 	 * start of the previous character.
113 	 *
114 	 * If not implement, default behaviour will work for fixed-width
115 	 * characters.
116 	 */
117 	int (*backspace)(struct udevice *dev);
118 };
119 
120 /* Get a pointer to the driver operations for a video console device */
121 #define vidconsole_get_ops(dev)  ((struct vidconsole_ops *)(dev)->driver->ops)
122 
123 /**
124  * vidconsole_putc_xy() - write a single character to a position
125  *
126  * @dev:	Device to write to
127  * @x_frac:	Fractional pixel X position (0=left-most pixel) which
128  *		is the X position multipled by VID_FRAC_DIV.
129  * @y:		Pixel Y position (0=top-most pixel)
130  * @ch:		Character to write
131  * @return number of fractional pixels that the cursor should move,
132  * if all is OK, -EAGAIN if we ran out of space on this line, other -ve
133  * on error
134  */
135 int vidconsole_putc_xy(struct udevice *dev, uint x, uint y, char ch);
136 
137 /**
138  * vidconsole_move_rows() - Move text rows from one place to another
139  *
140  * @dev:	Device to adjust
141  * @rowdst:	Destination text row (0=top)
142  * @rowsrc:	Source start text row
143  * @count:	Number of text rows to move
144  * @return 0 if OK, -ve on error
145  */
146 int vidconsole_move_rows(struct udevice *dev, uint rowdst, uint rowsrc,
147 			 uint count);
148 
149 /**
150  * vidconsole_set_row() - Set the colour of a text row
151  *
152  * Every pixel contained within the text row is adjusted
153  *
154  * @dev:	Device to adjust
155  * @row:	Text row to adjust (0=top)
156  * @clr:	Raw colour (pixel value) to write to each pixel
157  * @return 0 if OK, -ve on error
158  */
159 int vidconsole_set_row(struct udevice *dev, uint row, int clr);
160 
161 /**
162  * vidconsole_put_char() - Output a character to the current console position
163  *
164  * Outputs a character to the console and advances the cursor. This function
165  * handles wrapping to new lines and scrolling the console. Special
166  * characters are handled also: \n, \r, \b and \t.
167  *
168  * The device always starts with the cursor at position 0,0 (top left). It
169  * can be adjusted manually using vidconsole_position_cursor().
170  *
171  * @dev:	Device to adjust
172  * @ch:		Character to write
173  * @return 0 if OK, -ve on error
174  */
175 int vidconsole_put_char(struct udevice *dev, char ch);
176 
177 /**
178  * vidconsole_position_cursor() - Move the text cursor
179  *
180  * @dev:	Device to adjust
181  * @col:	New cursor text column
182  * @row:	New cursor text row
183  * @return 0 if OK, -ve on error
184  */
185 void vidconsole_position_cursor(struct udevice *dev, unsigned col,
186 				unsigned row);
187 
188 #endif
189