[PATCH v3 02/04] clk: shmobile: Make MSTP clock-output-names optional

[Magnus Damm <magnus.damm@gmail.com>]

From: Magnus Damm <damm+renesas@opensource.se>

This patch updates the MSTP driver to make the "clock-output-names"
DT property optional instead of mandatory. In case the DT property
is omitted then the function clk_register_clkdev() is skipped.

The default for new SoCs is to not use "clock-output-names".

This version of the patch is kind of early, so please handle with care.
So far the patch has only been tested with a single MSTP clock. =)

Not-Yet-Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
---

 drivers/clk/shmobile/clk-mstp.c |   15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

--- 0001/drivers/clk/shmobile/clk-mstp.c
+++ work/drivers/clk/shmobile/clk-mstp.c	2015-08-28 15:03:28.002366518 +0900
@@ -198,15 +198,12 @@ static void __init cpg_mstp_clocks_init(
 
 	for (i = 0; i < MSTP_MAX_CLOCKS; ++i) {
 		const char *parent_name;
-		const char *name;
+		const char *name = NULL;
 		u32 clkidx;
 		int ret;
 
-		/* Skip clocks with no name. */
 		ret = of_property_read_string_index(np, "clock-output-names",
 						    i, &name);
-		if (ret < 0 || strlen(name) == 0)
-			continue;
 
 		parent_name = of_clk_get_parent_name(np, i);
 		ret = of_property_read_u32_index(np, idxname, i, &clkidx);
@@ -214,12 +211,13 @@ static void __init cpg_mstp_clocks_init(
 			break;
 
 		if (clkidx >= MSTP_MAX_CLOCKS) {
-			pr_err("%s: invalid clock %s %s index %u)\n",
-			       __func__, np->name, name, clkidx);
+			pr_err("%s: invalid clock %s index %u)\n",
+			       __func__, np->name, clkidx);
 			continue;
 		}
 
-		clks[clkidx] = cpg_mstp_clock_register(name, parent_name,
+		clks[clkidx] = cpg_mstp_clock_register(name ? name : np->name,
+						       parent_name,
 						       clkidx, group);
 		if (!IS_ERR(clks[clkidx])) {
 			group->data.clk_num = max(group->data.clk_num,
@@ -232,7 +230,8 @@ static void __init cpg_mstp_clocks_init(
 			 * FIXME: Remove this when all devices that require a
 			 * clock will be instantiated from DT.
 			 */
-			clk_register_clkdev(clks[clkidx], name, NULL);
+			if (name) /* only if clock-output-names is provided */
+				clk_register_clkdev(clks[clkidx], name, NULL);
 		} else {
 			pr_err("%s: failed to register %s %s clock (%ld)\n",
 			       __func__, np->name, name, PTR_ERR(clks[clkidx]));