Add rtc tool

Add tool to handle RTD device ioctls.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

2 files changed, 158 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..61ff6a3
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+rtc
+rtc-sync
diff --git a/rtc.c b/rtc.c
new file mode 100644
index 0000000..1ca128a
--- /dev/null
+++ b/rtc.c
@@ -0,0 +1,156 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Real Time Clock tool
+ *
+ * Copyright (c) 2018 Alexandre Belloni <alexandre.belloni@bootlin.com>
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/rtc.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/ioctl.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+
+static char *rtc_file = "/dev/rtc0";
+
+#define IOCTL(f, r, d, rc) rc = ioctl(f, r, d); \
+if (rc) { \
+	fprintf(stderr, "%s returned %d (line %d)\n", #r, errno, __LINE__); \
+	exit(errno); \
+}
+
+#define ISODATEFMT "%04d-%02d-%02dT%02d:%02d:%02d"
+#define ISODATE(tm)  tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, \
+		       tm.tm_hour, tm.tm_min, tm.tm_sec
+
+static void usage(char *name)
+{
+	fprintf(stderr, "Usage: %s <command>\n", name);
+	fprintf(stderr, "       %s rd [rtc]\n", name);
+	fprintf(stderr, "       %s set YYYY-MM-DDThh:mm:ss [rtc]\n", name);
+	fprintf(stderr, "       %s wkalmrd [rtc]\n", name);
+	fprintf(stderr, "       %s wkalmset YYYY-MM-DDThh:mm:ss [rtc]\n", name);
+	fprintf(stderr, "       %s almread [rtc]\n", name);
+	fprintf(stderr, "       %s almset YYYY-MM-DDThh:mm:ss [rtc]\n", name);
+	fprintf(stderr, "       %s aieon [rtc]\n", name);
+	fprintf(stderr, "       %s aieoff [rtc]\n", name);
+
+	exit(EINVAL);
+}
+
+int main(int argc, char **argv)
+{
+	struct rtc_time tm;
+	struct rtc_wkalrm alm;
+	int fd, rc, cmd = 0;
+
+	if (argc < 2)
+		usage(argv[0]);
+
+	if (!strcmp(argv[1], "rd")) {
+		if (argc > 2)
+			rtc_file = argv[2];
+		cmd = RTC_RD_TIME;
+	} else if (!strcmp(argv[1], "set")) {
+		if (argc < 3)
+			usage(argv[0]);
+		if (argc > 3)
+			rtc_file = argv[3];
+		cmd = RTC_SET_TIME;
+		rc = sscanf(argv[2], "%d-%d-%dT%d:%d:%d", &tm.tm_year,
+			    &tm.tm_mon, &tm.tm_mday, &tm.tm_hour, &tm.tm_min,
+			    &tm.tm_sec);
+		tm.tm_year -= 1900;
+		tm.tm_mon -= 1;
+	} else if (!strcmp(argv[1], "wkalmrd")) {
+		if (argc > 2)
+			rtc_file = argv[2];
+		cmd = RTC_WKALM_RD;
+	} else if (!strcmp(argv[1], "wkalmset")) {
+		if (argc < 3)
+			usage(argv[0]);
+		if (argc > 3)
+			rtc_file = argv[3];
+		cmd = RTC_WKALM_SET;
+		rc = sscanf(argv[2], "%d-%d-%dT%d:%d:%d", &alm.time.tm_year,
+			    &alm.time.tm_mon, &alm.time.tm_mday,
+			    &alm.time.tm_hour, &alm.time.tm_min,
+			    &alm.time.tm_sec);
+		alm.time.tm_year -= 1900;
+		alm.time.tm_mon -= 1;
+		alm.enabled = 1;
+	} else if (!strcmp(argv[1], "aieon")) {
+		if (argc > 2)
+			rtc_file = argv[2];
+		cmd = RTC_AIE_ON;
+	} else if (!strcmp(argv[1], "aieoff")) {
+		if (argc > 2)
+			rtc_file = argv[2];
+		cmd = RTC_AIE_OFF;
+	} else if (!strcmp(argv[1], "almread")) {
+		if (argc > 2)
+			rtc_file = argv[2];
+		cmd = RTC_ALM_READ;
+	} else if (!strcmp(argv[1], "almset")) {
+		if (argc < 3)
+			usage(argv[0]);
+		if (argc > 3)
+			rtc_file = argv[3];
+		cmd = RTC_ALM_SET;
+		rc = sscanf(argv[2], "%d-%d-%dT%d:%d:%d", &tm.tm_year,
+			    &tm.tm_mon, &tm.tm_mday, &tm.tm_hour, &tm.tm_min,
+			    &tm.tm_sec);
+		alm.time.tm_year -= 1900;
+		alm.time.tm_mon -= 1;
+		alm.enabled = 1;
+	}
+
+	if (!cmd)
+		usage(argv[0]);
+
+	fd = open(rtc_file, O_RDONLY);
+	if (fd ==  -1) {
+		perror(rtc_file);
+		exit(errno);
+	}
+
+	switch (cmd) {
+	case RTC_RD_TIME:
+		IOCTL(fd, RTC_RD_TIME, &tm, rc);
+		printf("%s: " ISODATEFMT "\n", rtc_file, ISODATE(tm));
+		break;
+	case RTC_SET_TIME:
+		IOCTL(fd, RTC_SET_TIME, &tm, rc);
+		break;
+	case RTC_WKALM_RD:
+		IOCTL(fd, RTC_WKALM_RD, &alm, rc);
+		printf("%s: " ISODATEFMT "\n", rtc_file, ISODATE(alm.time));
+		break;
+	case RTC_WKALM_SET:
+		IOCTL(fd, RTC_WKALM_SET, &alm, rc);
+		break;
+	case RTC_ALM_READ:
+		IOCTL(fd, RTC_ALM_READ, &tm, rc);
+		printf("%s: " ISODATEFMT "\n", rtc_file, ISODATE(tm));
+		break;
+	case RTC_ALM_SET:
+		IOCTL(fd, RTC_ALM_SET, &tm, rc);
+		break;
+	case RTC_AIE_ON:
+		IOCTL(fd, RTC_AIE_ON, 0, rc);
+		break;
+	case RTC_AIE_OFF:
+		IOCTL(fd, RTC_AIE_OFF, 0, rc);
+		break;
+	}
+
+	close(fd);
+
+	return 0;
+}