[U-Boot] cmd: add wdt command

diff --git a/cmd/Kconfig b/cmd/Kconfig
index 0b07b3b9d7..2bdbfcb3d0 100644
--- a/cmd/Kconfig
+++ b/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
diff --git a/cmd/Makefile b/cmd/Makefile
index acb85f49fb..6b1c6b094e 100644
--- a/cmd/Makefile
+++ b/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
diff --git a/cmd/wdt.c b/cmd/wdt.c
new file mode 100644
index 0000000000..647d9899b4
--- /dev/null
+++ b/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));