include/video_console.h

   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