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>

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>
Rob Clark · Anatolij Gustschin
1 parent 889808da9b
Showing 5 changed files with 135 additions and 3 deletions Side-by-side Diff
drivers/video/Kconfig
drivers/video/vidconsole-uclass.c
drivers/video/video-uclass.c
include/video.h
include/video_console.h
@@ -65,6 +65,14 @@
 	  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
@@ -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;
@@ -87,7 +87,7 @@
 	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 @@
 	} else {
 		memset(priv->fb, priv->colour_bg, priv->fb_size);
 	}
-
-	return 0;
 }
  
 /* Flush video activity to the caches */
@@ -115,6 +115,13 @@
 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
  *
  * Some frame buffers are cached or have a secondary frame buffer. This
@@ -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 @@
 	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];
 };
  
 /**
...	...	@@ -65,6 +65,14 @@
65	65	this option, such displays will not be supported and console output
66	66	will be empty.
67	67
	68	+config VIDEO_ANSI
	69	+ bool "Support ANSI escape sequences in video console"
	70	+ depends on DM_VIDEO
	71	+ default y if DM_VIDEO
	72	+ help
	73	+ Enable ANSI escape sequence decoding for a more fully functional
	74	+ console.
	75	+
68	76	config CONSOLE_NORMAL
69	77	bool "Support a simple text console"
70	78	depends on DM_VIDEO
...	...	@@ -9,6 +9,7 @@
9	9	*/
10	10
11	11	#include <common.h>
	12	+#include <linux/ctype.h>
12	13	#include <dm.h>
13	14	#include <video.h>
14	15	#include <video_console.h>
15	16
16	17
...	...	@@ -107,12 +108,119 @@
107	108	video_sync(dev->parent);
108	109	}
109	110
	111	+static char parsenum(char s, int *num)
	112	+{
	113	+ char *end;
	114	+ *num = simple_strtol(s, &end, 10);
	115	+ return end;
	116	+}
	117	+
	118	+/*
	119	+ * Process a character while accumulating an escape string. Chars are
	120	+ * accumulated into escape_buf until the end of escape sequence is
	121	+ * found, at which point the sequence is parsed and processed.
	122	+ */
	123	+static void vidconsole_escape_char(struct udevice *dev, char ch)
	124	+{
	125	+ struct vidconsole_priv *priv = dev_get_uclass_priv(dev);
	126	+
	127	+ if (!IS_ENABLED(CONFIG_VIDEO_ANSI))
	128	+ goto error;
	129	+
	130	+ /* Sanity checking for bogus ESC sequences: */
	131	+ if (priv->escape_len >= sizeof(priv->escape_buf))
	132	+ goto error;
	133	+ if (priv->escape_len == 0 && ch != '[')
	134	+ goto error;
	135	+
	136	+ priv->escape_buf[priv->escape_len++] = ch;
	137	+
	138	+ /*
	139	+ * Escape sequences are terminated by a letter, so keep
	140	+ * accumulating until we get one:
	141	+ */
	142	+ if (!isalpha(ch))
	143	+ return;
	144	+
	145	+ /*
	146	+ * clear escape mode first, otherwise things will get highly
	147	+ * surprising if you hit any debug prints that come back to
	148	+ * this console.
	149	+ */
	150	+ priv->escape = 0;
	151	+
	152	+ switch (ch) {
	153	+ case 'H':
	154	+ case 'f': {
	155	+ int row, col;
	156	+ char *s = priv->escape_buf;
	157	+
	158	+ /*
	159	+ * Set cursor position: [%d;%df or [%d;%dH
	160	+ */
	161	+ s++; /* [ */
	162	+ s = parsenum(s, &row);
	163	+ s++; /* ; */
	164	+ s = parsenum(s, &col);
	165	+
	166	+ priv->ycur = row * priv->y_charsize;
	167	+ priv->xcur_frac = priv->xstart_frac +
	168	+ VID_TO_POS(col * priv->x_charsize);
	169	+
	170	+ break;
	171	+ }
	172	+ case 'J': {
	173	+ int mode;
	174	+
	175	+ /*
	176	+ * Clear part/all screen:
	177	+ * [J or [0J - clear screen from cursor down
	178	+ * [1J - clear screen from cursor up
	179	+ * [2J - clear entire screen
	180	+ *
	181	+ * TODO we really only handle entire-screen case, others
	182	+ * probably require some additions to video-uclass (and
	183	+ * are not really needed yet by efi_console)
	184	+ */
	185	+ parsenum(priv->escape_buf + 1, &mode);
	186	+
	187	+ if (mode == 2) {
	188	+ video_clear(dev->parent);
	189	+ video_sync(dev->parent);
	190	+ priv->ycur = 0;
	191	+ priv->xcur_frac = priv->xstart_frac;
	192	+ } else {
	193	+ debug("unsupported clear mode: %d\n", mode);
	194	+ }
	195	+ break;
	196	+ }
	197	+ default:
	198	+ debug("unrecognized escape sequence: %*s\n",
	199	+ priv->escape_len, priv->escape_buf);
	200	+ }
	201	+
	202	+ return;
	203	+
	204	+error:
	205	+ /* something went wrong, just revert to normal mode: */
	206	+ priv->escape = 0;
	207	+}
	208	+
110	209	int vidconsole_put_char(struct udevice *dev, char ch)
111	210	{
112	211	struct vidconsole_priv *priv = dev_get_uclass_priv(dev);
113	212	int ret;
114	213
	214	+ if (priv->escape) {
	215	+ vidconsole_escape_char(dev, ch);
	216	+ return 0;
	217	+ }
	218	+
115	219	switch (ch) {
	220	+ case '\x1b':
	221	+ priv->escape_len = 0;
	222	+ priv->escape = 1;
	223	+ break;
116	224	case '\a':
117	225	/* beep */
118	226	break;
...	...	@@ -87,7 +87,7 @@
87	87	return 0;
88	88	}
89	89
90		-static int video_clear(struct udevice *dev)
	90	+void video_clear(struct udevice *dev)
91	91	{
92	92	struct video_priv *priv = dev_get_uclass_priv(dev);
93	93
...	...	@@ -100,8 +100,6 @@
100	100	} else {
101	101	memset(priv->fb, priv->colour_bg, priv->fb_size);
102	102	}
103		-
104		- return 0;
105	103	}
106	104
107	105	/* Flush video activity to the caches */
...	...	@@ -115,6 +115,13 @@
115	115	int video_reserve(ulong *addrp);
116	116
117	117	/**
	118	+ * video_clear() - Clear a device's frame buffer to background color.
	119	+ *
	120	+ * @dev: Device to clear
	121	+ */
	122	+void video_clear(struct udevice *dev);
	123	+
	124	+/**
118	125	* video_sync() - Sync a device's frame buffer with its hardware
119	126	*
120	127	* Some frame buffers are cached or have a secondary frame buffer. This
...	...	@@ -29,6 +29,9 @@
29	29	* @xsize_frac: Width of the display in fractional units
30	30	* @xstart_frac: Left margin for the text console in fractional units
31	31	* @last_ch: Last character written to the text console on this line
	32	+ * @escape: TRUE if currently accumulating an ANSI escape sequence
	33	+ * @escape_len: Length of accumulated escape sequence so far
	34	+ * @escape_buf: Buffer to accumulate escape sequence
32	35	*/
33	36	struct vidconsole_priv {
34	37	struct stdio_dev sdev;
...	...	@@ -42,6 +45,14 @@
42	45	int xsize_frac;
43	46	int xstart_frac;
44	47	int last_ch;
	48	+ /*
	49	+ * ANSI escape sequences are accumulated character by character,
	50	+ * starting after the ESC char (0x1b) until the entire sequence
	51	+ * is consumed at which point it is acted upon.
	52	+ */
	53	+ int escape;
	54	+ int escape_len;
	55	+ char escape_buf[32];
45	56	};
46	57
47	58	/**