event: Add a command

Add a command to show the available events.

Signed-off-by: Simon Glass <sjg@chromium.org>

MAINTAINERS

@@ -812,6 +812,7 @@ F:	scripts/env2string.awk
 EVENTS
 M:	Simon Glass <sjg@chromium.org>
 S:	Maintained
+F:	cmd/event.c
 F:	common/event.c
 F:	include/event.h
 F:	test/common/event.c

cmd/Kconfig

@@ -2367,6 +2367,14 @@ config CMD_DIAG
 	  available tests and running either all the tests, or specific tests
 	  identified by name.
 
+config CMD_EVENT
+	bool "event - Show information about events"
+	default y if EVENT_DEBUG
+	help
+	  This enables the 'event' command which provides information about
+	  events and event-handler routines. This can help to device event
+	  hadling.
+
 config CMD_IRQ
 	bool "irq - Show information about interrupts"
 	depends on !ARM && !MIPS && !RISCV && !SH

cmd/Makefile

@@ -53,6 +53,7 @@ obj-$(CONFIG_CMD_DIAG) += diag.o
 endif
 obj-$(CONFIG_CMD_ADTIMG) += adtimg.o
 obj-$(CONFIG_CMD_ABOOTIMG) += abootimg.o
+obj-$(CONFIG_CMD_EVENT) += event.o
 obj-$(CONFIG_CMD_EXTENSION) += extension_board.o
 obj-$(CONFIG_CMD_ECHO) += echo.o
 obj-$(CONFIG_ENV_IS_IN_EEPROM) += eeprom.o

cmd/event.c

@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Command-line access to events
+ *
+ * Copyright 2021 Google LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#include <common.h>
+#include <command.h>
+#include <event.h>
+
+static int do_event_list(struct cmd_tbl *cmdtp, int flag, int argc,
+			 char *const argv[])
+{
+	event_show_spy_list();
+
+	return 0;
+}
+
+#ifdef CONFIG_SYS_LONGHELP
+static char event_help_text[] =
+	"event list   - list event spies";
+#endif
+
+U_BOOT_CMD_WITH_SUBCMDS(event, "Events", event_help_text,
+	U_BOOT_SUBCMD_MKENT(list, 1, 1, do_event_list));

include/event.h

@@ -141,6 +141,9 @@ static inline const char *event_spy_id(struct evspy_info *spy)
 int event_register(const char *id, enum event_t type, event_handler_t func,
 		   void *ctx);
 
+/** event_show_spy_list( - Show a list of event spies */
+void event_show_spy_list(void);
+
 #if CONFIG_IS_ENABLED(EVENT)
 /**
  * event_notify() - notify spies about an event