dm: video: Add basic ANSI escape sequence support

Really just the subset that is needed by efi_console.  Perhaps more will
be added later, for example color support would be useful to implement
efi_cout_set_attribute().

Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Rob Clark 2017-09-13 18:12:21 -04:00 committed by Anatolij Gustschin
parent 889808da9b
commit a085aa1f27
5 changed files with 135 additions and 3 deletions

View file

@ -65,6 +65,14 @@ config VIDEO_BPP32
this option, such displays will not be supported and console output
will be empty.
config VIDEO_ANSI
bool "Support ANSI escape sequences in video console"
depends on DM_VIDEO
default y if DM_VIDEO
help
Enable ANSI escape sequence decoding for a more fully functional
console.
config CONSOLE_NORMAL
bool "Support a simple text console"
depends on DM_VIDEO

View file

@ -9,6 +9,7 @@
*/
#include <common.h>
#include <linux/ctype.h>
#include <dm.h>
#include <video.h>
#include <video_console.h>
@ -107,12 +108,119 @@ static void vidconsole_newline(struct udevice *dev)
video_sync(dev->parent);
}
static char *parsenum(char *s, int *num)
{
char *end;
*num = simple_strtol(s, &end, 10);
return end;
}
/*
* Process a character while accumulating an escape string. Chars are
* accumulated into escape_buf until the end of escape sequence is
* found, at which point the sequence is parsed and processed.
*/
static void vidconsole_escape_char(struct udevice *dev, char ch)
{
struct vidconsole_priv *priv = dev_get_uclass_priv(dev);
if (!IS_ENABLED(CONFIG_VIDEO_ANSI))
goto error;
/* Sanity checking for bogus ESC sequences: */
if (priv->escape_len >= sizeof(priv->escape_buf))
goto error;
if (priv->escape_len == 0 && ch != '[')
goto error;
priv->escape_buf[priv->escape_len++] = ch;
/*
* Escape sequences are terminated by a letter, so keep
* accumulating until we get one:
*/
if (!isalpha(ch))
return;
/*
* clear escape mode first, otherwise things will get highly
* surprising if you hit any debug prints that come back to
* this console.
*/
priv->escape = 0;
switch (ch) {
case 'H':
case 'f': {
int row, col;
char *s = priv->escape_buf;
/*
* Set cursor position: [%d;%df or [%d;%dH
*/
s++; /* [ */
s = parsenum(s, &row);
s++; /* ; */
s = parsenum(s, &col);
priv->ycur = row * priv->y_charsize;
priv->xcur_frac = priv->xstart_frac +
VID_TO_POS(col * priv->x_charsize);
break;
}
case 'J': {
int mode;
/*
* Clear part/all screen:
* [J or [0J - clear screen from cursor down
* [1J - clear screen from cursor up
* [2J - clear entire screen
*
* TODO we really only handle entire-screen case, others
* probably require some additions to video-uclass (and
* are not really needed yet by efi_console)
*/
parsenum(priv->escape_buf + 1, &mode);
if (mode == 2) {
video_clear(dev->parent);
video_sync(dev->parent);
priv->ycur = 0;
priv->xcur_frac = priv->xstart_frac;
} else {
debug("unsupported clear mode: %d\n", mode);
}
break;
}
default:
debug("unrecognized escape sequence: %*s\n",
priv->escape_len, priv->escape_buf);
}
return;
error:
/* something went wrong, just revert to normal mode: */
priv->escape = 0;
}
int vidconsole_put_char(struct udevice *dev, char ch)
{
struct vidconsole_priv *priv = dev_get_uclass_priv(dev);
int ret;
if (priv->escape) {
vidconsole_escape_char(dev, ch);
return 0;
}
switch (ch) {
case '\x1b':
priv->escape_len = 0;
priv->escape = 1;
break;
case '\a':
/* beep */
break;

View file

@ -87,7 +87,7 @@ int video_reserve(ulong *addrp)
return 0;
}
static int video_clear(struct udevice *dev)
void video_clear(struct udevice *dev)
{
struct video_priv *priv = dev_get_uclass_priv(dev);
@ -100,8 +100,6 @@ static int video_clear(struct udevice *dev)
} else {
memset(priv->fb, priv->colour_bg, priv->fb_size);
}
return 0;
}
/* Flush video activity to the caches */

View file

@ -114,6 +114,13 @@ struct video_ops {
*/
int video_reserve(ulong *addrp);
/**
* video_clear() - Clear a device's frame buffer to background color.
*
* @dev: Device to clear
*/
void video_clear(struct udevice *dev);
/**
* video_sync() - Sync a device's frame buffer with its hardware
*

View file

@ -29,6 +29,9 @@
* @xsize_frac: Width of the display in fractional units
* @xstart_frac: Left margin for the text console in fractional units
* @last_ch: Last character written to the text console on this line
* @escape: TRUE if currently accumulating an ANSI escape sequence
* @escape_len: Length of accumulated escape sequence so far
* @escape_buf: Buffer to accumulate escape sequence
*/
struct vidconsole_priv {
struct stdio_dev sdev;
@ -42,6 +45,14 @@ struct vidconsole_priv {
int xsize_frac;
int xstart_frac;
int last_ch;
/*
* ANSI escape sequences are accumulated character by character,
* starting after the ESC char (0x1b) until the entire sequence
* is consumed at which point it is acted upon.
*/
int escape;
int escape_len;
char escape_buf[32];
};
/**