From 6e6767175fb02f2f3e62f2e8c336c48a346c23d6 Mon Sep 17 00:00:00 2001
From: Werner Almesberger <werner@almesberger.net>
Date: Tue, 15 Jan 2013 14:08:38 -0300
Subject: [PATCH] ubb-patgen/ubb-patgen.c: clean up usage (-c selects clkout
 only; -C to monitor)

... and active_s is no longer used with a pattern.
---
 ubb-patgen/ubb-patgen.c | 64 ++++++++++++++++++++++++-----------------
 1 file changed, 38 insertions(+), 26 deletions(-)

diff --git a/ubb-patgen/ubb-patgen.c b/ubb-patgen/ubb-patgen.c
index 361d214..618f545 100644
--- a/ubb-patgen/ubb-patgen.c
+++ b/ubb-patgen/ubb-patgen.c
@@ -275,13 +275,8 @@ static void mmc_buffer(const struct mmcclk *clk,
 	 * well-defined state.
 	 */
 
-	MSC_STRPCL = 1 << 3;	/* reset the MSC */
-
-	while (MSC_STAT & (1 << 15));	/* wait until reset finishes */
-
 	dma_setup(buf, nibbles);
 
-	MSC_CLKRT = clk->clkrt;	/* cleared by MSC reset */
 	MSC_STRPCL = 2;		/* start the bus clock */
 	MSC_RESTO = 0xffff;	/* maximum response time-out */
 	MSC_BLKLEN = 0xfff;	/* never reach the end (with CRC) */
@@ -448,12 +443,15 @@ static void usage(const char *name)
 {
         fprintf(stderr,
 "usage: %s\n"
-"usage: %s [-b freq_hz] [-f freq_hz] [-c] [-q] [pattern] active_s\n\n"
+"       %s [-b freq_hz] [-f freq_hz] -c [-q] [active_s]\n"
+"       %s [-b freq_hz] [-f freq_hz] [-C] [-q] pattern\n\n"
 "  -b freq_hz  set bus clock to the specified frequency (default: 1 MHz)\n"
-"  -c          output bus clock on CLK\n"
+"  -c          output bus clock on CLK without sending a pattern\n"
+"  -C          temporarily output bus clock on CLK (for debugging)\n"
 "  -f freq_hz  set pattern rate (default: same as bus clock)\n"
 "  -q          quiet. Don't report clock differences.\n\n"
 "  active_s    keep running that many seconds after setting the clock\n"
+"              (default: exit immediately but leave the clock on)\n"
 "  pattern     send the specified pattern on DAT0 through DAT3\n\n"
 "Frequency: the frequency in Hz, optionally followed by \"M\" or \"k\",\n"
 "  optionally followed by \"Hz\", optionally followed by \"+\" or \"-\".\n"
@@ -461,7 +459,7 @@ static void usage(const char *name)
 "  Without +/-, the closest available frequency is selected.\n"
 "Pattern: hex digits corresponding to 1 for DAT0, 2 for DAT1, etc.\n"
 "  {n} repeats the preceding digit n times, e.g., 1{3} is equivalent to 111.\n"
-    , name, name);
+    , name, name, name);
 	exit(1);
 }
 
@@ -469,16 +467,17 @@ static void usage(const char *name)
 int main(int argc, char **argv)
 {
 	struct mmcclk clk;
-	int bus_hz = 0, clkout = 0, bus_rel = 0;
+	int bus_hz = 0, clk_only = 0, clkout = 0, bus_rel = 0;
 	int pattern_hz = 0, pattern_rel = 0;
 	const char *pattern = NULL;
 	int quiet = 0;
-	double active_s;
+	double active_s = 0;
 	struct timespec active_ns;
+	int keep_clk = 1;
 	char *end;
 	int c;
 
-	while ((c = getopt(argc, argv, "b:cq")) != EOF)
+	while ((c = getopt(argc, argv, "b:cCq")) != EOF)
 		switch (c) {
 		case 'b':
 			if (!frequency(optarg, &bus_hz, &bus_rel))
@@ -489,6 +488,9 @@ int main(int argc, char **argv)
 				usage(*argv);
 			break;
 		case 'c':
+			clk_only = 1;
+			/* fall through */
+		case 'C':
 			clkout = 1;
 			break;
 		case 'q':
@@ -500,20 +502,24 @@ int main(int argc, char **argv)
 
 	switch (argc-optind) {
 	case 0:
-		if (clkout || quiet)
+		if (clk_only)
+			break;
+		if (bus_hz || pattern_hz || clkout || quiet)
 			usage(*argv);
 		ubb_open(UBB_ALL);
 		show_frequencies();
 		return 1;
-	case 2:
-		pattern = argv[optind];
-		/* fall through */
 	case 1:
-		active_s = strtod(argv[argc-1], &end);
-		if (*end)
-			usage(*argv);
-		active_ns.tv_sec = (int) active_s;
-		active_ns.tv_nsec = (active_s-(int) active_s)*1e9;
+		if (clk_only) {
+			active_s = strtod(argv[argc-1], &end);
+			if (*end)
+				usage(*argv);
+			active_ns.tv_sec = (int) active_s;
+			active_ns.tv_nsec = (active_s-(int) active_s)*1e9;
+			keep_clk = 0;
+		} else {
+			pattern = argv[optind];
+		}
 		break;
 	default:
 		usage(*argv);
@@ -550,12 +556,18 @@ int main(int argc, char **argv)
 		dma_pattern(&clk, pattern,
 		    UBB_DAT0 | UBB_DAT1 | UBB_DAT2 | UBB_DAT3);
 
-	if (nanosleep(&active_ns, NULL))
-		perror("nanosleep");
-
-	mmcclk_stop();
-
-	ubb_close(UBB_DAT0 | UBB_DAT1 | UBB_DAT2 | UBB_DAT3);
+	if (active_s)
+		if (nanosleep(&active_ns, NULL))
+			perror("nanosleep");
+	if (pattern) {
+		mmcclk_stop();
+		ubb_close(UBB_DAT0 | UBB_DAT1 | UBB_DAT2 | UBB_DAT3);
+	} else if (keep_clk) {
+		ubb_close(UBB_CLK);
+	} else {
+		mmcclk_stop();
+		ubb_close(0);
+	}
 
 	return 0;
 }