cmd: add wdt command

Add a command to control the watchdog devices. This is useful if the
watchdog is rather long running (eg. seconds) and it should be
controlled by scripts. It is also handy during debugging.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Stefan Roese <sr@denx.de>

cmd/Kconfig

@@ -1101,6 +1101,12 @@ config CMD_VIRTIO
 	help
 	  VirtIO block device support
 
+config CMD_WDT
+	bool "wdt"
+	depends on WDT
+	help
+	  This provides commands to control the watchdog timer devices.
+
 config CMD_AXI
 	bool "axi"
 	depends on AXI

cmd/Makefile

@@ -142,6 +142,7 @@ obj-$(CONFIG_CMD_UBIFS) += ubifs.o
 obj-$(CONFIG_CMD_UNIVERSE) += universe.o
 obj-$(CONFIG_CMD_UNZIP) += unzip.o
 obj-$(CONFIG_CMD_VIRTIO) += virtio.o
+obj-$(CONFIG_CMD_WDT) += wdt.o
 obj-$(CONFIG_CMD_LZMADEC) += lzmadec.o
 
 obj-$(CONFIG_CMD_USB) += usb.o disk.o

cmd/wdt.c

@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Watchdog commands
+ *
+ * Copyright (c) 2019 Michael Walle <michael@walle.cc>
+ */
+
+#include <common.h>
+#include <command.h>
+#include <dm.h>
+#include <wdt.h>
+
+static struct udevice *currdev;
+
+static int do_wdt_list(cmd_tbl_t *cmdtp, int flag, int argc,
+		       char *const argv[])
+{
+	struct udevice *dev;
+	struct uclass *uc;
+	int ret;
+
+	ret = uclass_get(UCLASS_WDT, &uc);
+	if (ret)
+		return CMD_RET_FAILURE;
+
+	uclass_foreach_dev(dev, uc)
+		printf("%s (%s)\n", dev->name, dev->driver->name);
+
+	return CMD_RET_SUCCESS;
+}
+
+static int do_wdt_dev(cmd_tbl_t *cmdtp, int flag, int argc,
+		      char *const argv[])
+{
+	int ret;
+
+	if (argc > 1) {
+		ret = uclass_get_device_by_name(UCLASS_WDT, argv[1], &currdev);
+		if (ret) {
+			printf("Can't get the watchdog timer: %s\n", argv[1]);
+			return CMD_RET_FAILURE;
+		}
+	} else {
+		if (!currdev) {
+			printf("No watchdog timer device set!\n");
+			return CMD_RET_FAILURE;
+		}
+		printf("dev: %s\n", currdev->name);
+	}
+
+	return CMD_RET_SUCCESS;
+}
+
+static int check_currdev(void)
+{
+	if (!currdev) {
+		printf("No device set, use 'wdt dev' first\n");
+		return CMD_RET_FAILURE;
+	}
+	return 0;
+}
+
+static int do_wdt_start(cmd_tbl_t *cmdtp, int flag, int argc,
+			char *const argv[])
+{
+	int ret;
+	u64 timeout;
+	ulong flags = 0;
+
+	if (argc < 2)
+		return CMD_RET_USAGE;
+
+	ret = check_currdev();
+	if (ret)
+		return ret;
+
+	timeout = simple_strtoull(argv[1], NULL, 0);
+	if (argc > 2)
+		flags = simple_strtoul(argv[2], NULL, 0);
+
+	ret = wdt_start(currdev, timeout, flags);
+	if (ret == -ENOSYS) {
+		printf("Starting watchdog timer not supported.\n");
+		return CMD_RET_FAILURE;
+	} else if (ret) {
+		printf("Starting watchdog timer failed (%d)\n", ret);
+		return CMD_RET_FAILURE;
+	}
+
+	return CMD_RET_SUCCESS;
+}
+
+static int do_wdt_stop(cmd_tbl_t *cmdtp, int flag, int argc,
+		       char *const argv[])
+{
+	int ret;
+
+	ret = check_currdev();
+	if (ret)
+		return ret;
+
+	ret = wdt_stop(currdev);
+	if (ret == -ENOSYS) {
+		printf("Stopping watchdog timer not supported.\n");
+		return CMD_RET_FAILURE;
+	} else if (ret) {
+		printf("Stopping watchdog timer failed (%d)\n", ret);
+		return CMD_RET_FAILURE;
+	}
+
+	return CMD_RET_SUCCESS;
+}
+
+static int do_wdt_reset(cmd_tbl_t *cmdtp, int flag, int argc,
+			char *const argv[])
+{
+	int ret;
+
+	ret = check_currdev();
+	if (ret)
+		return ret;
+
+	ret = wdt_reset(currdev);
+	if (ret == -ENOSYS) {
+		printf("Resetting watchdog timer not supported.\n");
+		return CMD_RET_FAILURE;
+	} else if (ret) {
+		printf("Resetting watchdog timer failed (%d)\n", ret);
+		return CMD_RET_FAILURE;
+	}
+
+	return CMD_RET_SUCCESS;
+}
+
+static int do_wdt_expire(cmd_tbl_t *cmdtp, int flag, int argc,
+			 char *const argv[])
+{
+	int ret;
+	ulong flags = 0;
+
+	ret = check_currdev();
+	if (ret)
+		return ret;
+
+	if (argc > 1)
+		flags = simple_strtoul(argv[1], NULL, 0);
+
+	ret = wdt_expire_now(currdev, flags);
+	if (ret == -ENOSYS) {
+		printf("Expiring watchdog timer not supported.\n");
+		return CMD_RET_FAILURE;
+	} else if (ret) {
+		printf("Expiring watchdog timer failed (%d)\n", ret);
+		return CMD_RET_FAILURE;
+	}
+
+	return CMD_RET_SUCCESS;
+}
+
+static char wdt_help_text[] =
+	"list - list watchdog devices\n"
+	"wdt dev [<name>] - get/set current watchdog device\n"
+	"wdt start <timeout ms> [flags] - start watchdog timer\n"
+	"wdt stop - stop watchdog timer\n"
+	"wdt reset - reset watchdog timer\n"
+	"wdt expire [flags] - expire watchdog timer immediately\n";
+
+U_BOOT_CMD_WITH_SUBCMDS(wdt, "Watchdog sub-system", wdt_help_text,
+	U_BOOT_SUBCMD_MKENT(list, 1, 1, do_wdt_list),
+	U_BOOT_SUBCMD_MKENT(dev, 2, 1, do_wdt_dev),
+	U_BOOT_SUBCMD_MKENT(start, 3, 1, do_wdt_start),
+	U_BOOT_SUBCMD_MKENT(stop, 1, 1, do_wdt_stop),
+	U_BOOT_SUBCMD_MKENT(reset, 1, 1, do_wdt_reset),
+	U_BOOT_SUBCMD_MKENT(expire, 2, 1, do_wdt_expire));