diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/font.h | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/include/linux/font.h b/include/linux/font.h index 5401f07dd6ce..3bd49d914b22 100644 --- a/include/linux/font.h +++ b/include/linux/font.h @@ -11,11 +11,51 @@ #ifndef _VIDEO_FONT_H #define _VIDEO_FONT_H +#include <linux/math.h> #include <linux/types.h> struct console_font; /* + * Glyphs + */ + +/** + * font_glyph_pitch - Calculates the number of bytes per scanline + * @width: The glyph width in bits per scanline + * + * A glyph's pitch is the number of bytes in a single scanline, rounded + * up to the next full byte. The parameter @width receives the number + * of visible bits per scanline. For example, if width is 14 bytes per + * scanline, the pitch is 2 bytes per scanline. If width is 8 bits per + * scanline, the pitch is 1 byte per scanline. + * + * Returns: + * The number of bytes in a single scanline of the glyph + */ +static inline unsigned int font_glyph_pitch(unsigned int width) +{ + return DIV_ROUND_UP(width, 8); +} + +/** + * font_glyph_size - Calculates the number of bytes per glyph + * @width: The glyph width in bits per scanline + * @vpitch: The number of scanlines in the glyph + * + * The number of bytes in a glyph depends on the pitch and the number + * of scanlines. font_glyph_size automatically calculates the pitch + * from the given width. The parameter @vpitch gives the number of + * scanlines, which is usually the glyph's height in scanlines. Fonts + * coming from user space can sometimes have a different vertical pitch + * with empty scanlines between two adjacent glyphs. + */ +static inline unsigned int font_glyph_size(unsigned int width, unsigned int vpitch) +{ + return font_glyph_pitch(width) * vpitch; +} + +/* * font_data_t and helpers */ |