[PATCH 2/2] commands: clk_dump: add json output option

[Ahmad Fatoum]

This formats the clock tree and the enable_count and rate of each clock
into the JSON format. This is useful to run validation scripts against
it that were originally written for Linux' /sys/kernel/debug/clk/clk_dump.

Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
---
 commands/clk.c      |  8 ++++--
 drivers/clk/clk.c   | 65 ++++++++++++++++++++++++++++++++++++++-------
 include/linux/clk.h |  1 +
 3 files changed, 63 insertions(+), 11 deletions(-)

diff --git a/commands/clk.c b/commands/clk.c
index 290acd842e78..210b61306a2e 100644
--- a/commands/clk.c
+++ b/commands/clk.c
@@ -166,11 +166,14 @@ static int do_clk_dump(int argc, char *argv[])
 	int opt, flags = 0;
 	struct clk *clk;
 
-	while ((opt = getopt(argc, argv, "v")) > 0) {
+	while ((opt = getopt(argc, argv, "vj")) > 0) {
 		switch(opt) {
 		case 'v':
 			flags |= CLK_DUMP_VERBOSE;
 			break;
+		case 'j':
+			flags |= CLK_DUMP_JSON;
+			break;
 		default:
 			return -EINVAL;
 
@@ -194,12 +197,13 @@ static int do_clk_dump(int argc, char *argv[])
 BAREBOX_CMD_HELP_START(clk_dump)
 BAREBOX_CMD_HELP_TEXT("Options:")
 BAREBOX_CMD_HELP_OPT ("-v",  "verbose")
+BAREBOX_CMD_HELP_OPT ("-j",  "json output")
 BAREBOX_CMD_HELP_END
 
 BAREBOX_CMD_START(clk_dump)
 	.cmd		= do_clk_dump,
 	BAREBOX_CMD_DESC("show information about registered clocks")
-	BAREBOX_CMD_OPTS("[-v] [clkname]")
+	BAREBOX_CMD_OPTS("[-vj] [clkname]")
 	BAREBOX_CMD_GROUP(CMD_GRP_INFO)
 	BAREBOX_CMD_HELP(cmd_clk_dump_help)
 	BAREBOX_CMD_COMPLETE(clk_name_complete)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index f9abd3147766..4c09c4e322f5 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1033,7 +1033,7 @@ static const char *clk_parent_name_by_index(struct clk *clk, u8 idx)
 	return "unknown";
 }
 
-static void dump_one(struct clk *clk, int flags, int indent)
+static void dump_one_summary(struct clk *clk, int flags, int indent)
 {
 	int enabled = clk_is_enabled(clk);
 	const char *hwstat, *stat;
@@ -1063,6 +1063,32 @@ static void dump_one(struct clk *clk, int flags, int indent)
 	}
 }
 
+static void dump_one_json(struct clk *clk, int flags, int indent)
+{
+	printf("\"%s\": { \"rate\": %lu,\"enable_count\": %d",
+	       clk->name,
+	       clk_get_rate(clk),
+	       clk->enable_count);
+}
+
+static void dump_one(struct clk *clk, int flags, int indent)
+{
+	if (flags & CLK_DUMP_JSON)
+		dump_one_json(clk, flags, indent);
+	else
+		dump_one_summary(clk, flags, indent);
+}
+
+static inline bool json_puts(const char *str, int flags)
+{
+	if (flags & CLK_DUMP_JSON) {
+		puts(str);
+		return true;
+	}
+
+	return false;
+}
+
 static void dump_subtree(struct clk *clk, int flags, int indent)
 {
 	struct clk *c;
@@ -1072,21 +1098,34 @@ static void dump_subtree(struct clk *clk, int flags, int indent)
 	list_for_each_entry(c, &clks, list) {
 		struct clk *parent = clk_get_parent(c);
 
-		if (parent == clk)
+		if (parent == clk) {
+			json_puts(",", flags);
 			dump_subtree(c, flags, indent + 1);
+		}
 	}
+
+	json_puts("}", flags);
 }
 
 void clk_dump(int flags)
 {
+	bool first_node = true;
 	struct clk *c;
 
+	json_puts("{", flags);
+
 	list_for_each_entry(c, &clks, list) {
 		struct clk *parent = clk_get_parent(c);
 
-		if (IS_ERR_OR_NULL(parent))
+		if (IS_ERR_OR_NULL(parent)) {
+			if (!first_node)
+				json_puts(",", flags);
+			first_node = false;
 			dump_subtree(c, flags, 0);
+		}
 	}
+
+	json_puts("}\n", flags);
 }
 
 static int clk_print_parent(struct clk *clk, int flags)
@@ -1107,21 +1146,29 @@ static int clk_print_parent(struct clk *clk, int flags)
 
 void clk_dump_one(struct clk *clk, int flags)
 {
-	int indent;
+	int indent = 0;
 	struct clk *c;
 
-	indent = clk_print_parent(clk, flags);
+	if (json_puts("{", flags)) {
+		dump_one(clk, flags, indent);
+	} else {
+		indent = clk_print_parent(clk, flags);
 
-	printf("\033[1m");
-	dump_one(clk, flags, indent);
-	printf("\033[0m");
+		printf("\033[1m");
+		dump_one(clk, flags, indent);
+		printf("\033[0m");
+	}
 
 	list_for_each_entry(c, &clks, list) {
 		struct clk *parent = clk_get_parent(c);
 
-		if (parent == clk)
+		if (parent == clk) {
+			json_puts(",", flags);
 			dump_subtree(c, flags, indent + 1);
+		}
 	}
+
+	json_puts("}}\n", flags);
 }
 
 int clk_name_complete(struct string_list *sl, char *instr)
diff --git a/include/linux/clk.h b/include/linux/clk.h
index f2e3a443c20f..c467bcf8ddda 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -725,6 +725,7 @@ static inline int clk_hw_register(struct device *dev, struct clk_hw *hw)
 struct clk *clk_lookup(const char *name);
 
 #define CLK_DUMP_VERBOSE	(1 << 0)
+#define CLK_DUMP_JSON		(1 << 1)
 void clk_dump(int flags);
 void clk_dump_one(struct clk *clk, int flags);
 
-- 
2.39.2