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>
diff --git a/drivers/video/vidconsole-uclass.c b/drivers/video/vidconsole-uclass.c
index e081d5a..37eb2a0 100644
--- a/drivers/video/vidconsole-uclass.c
+++ b/drivers/video/vidconsole-uclass.c
@@ -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 @@
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;