[PATCH v4 05/10] clk: support init->parent_data

[Steffen Trumtrar]

Linux clk driver supports matching parents via init->parent_data instead
of init->parent_names.

Add support for this feature to barebox, too.
Linux however supports setting a "name" and "fw_name" for a parent
clock. "fw_name" is a local name for the provider registering the clock
and "name" is a globally unique parent name. For the time being, only
support the globally unique "name" field.

Signed-off-by: Steffen Trumtrar <s.trumtrar at pengutronix.de>
---
 drivers/clk/clk.c | 49 ++++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 42 insertions(+), 7 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index ec8c06b61bfb65dbef365d77b6a7445557ce72e5..d7f9ec23b06876da4159d6b82539b047f335f678 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -483,11 +483,26 @@ int bclk_register(struct clk *clk)
 	return ret;
 }
 
+static int clk_cpy_name(const char **dst_p, const char *src, bool must_exist)
+{
+	const char *dst;
+
+	if (!src) {
+		if (must_exist)
+			return -EINVAL;
+		return 0;
+	}
+
+	*dst_p = dst = xstrdup(src);
+
+	return 0;
+}
+
 struct clk *clk_register(struct device *dev, struct clk_hw *hw)
 {
 	struct clk *clk;
 	const struct clk_init_data *init = hw->init;
-	char **parent_names = NULL;
+	const char **parent_names = NULL;
 	int i, ret;
 
 	if (!hw->init)
@@ -503,14 +518,34 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
 
 	clk->parents = xzalloc(sizeof(struct clk *) * clk->num_parents);
 
-	if (init->parent_names) {
+	if (init->parent_names || init->parent_data) {
 		parent_names = xzalloc(init->num_parents * sizeof(char *));
 
-		for (i = 0; i < init->num_parents; i++)
-			parent_names[i] = xstrdup(init->parent_names[i]);
-
-		clk->parent_names = (const char *const*)parent_names;
-
+		for (i = 0; i < init->num_parents; i++) {
+			if (init->parent_names) {
+				ret = clk_cpy_name(&parent_names[i],
+						   init->parent_names[i], true);
+				if (ret)
+					return ERR_PTR(ret);
+			} else if (init->parent_data) {
+				/* Linux copies fw_name and if successful also name.
+				 * As fw_name is not handled in barebox, just copy the
+				 * name field and fallback to hw->clk.name if it doesn't
+				 * exist.
+				 */
+				ret = clk_cpy_name(&parent_names[i],
+						   init->parent_data[i].name,
+						   true);
+				if (ret) {
+					ret = clk_cpy_name(&parent_names[i],
+							   init->parent_data[i].hw->clk.name,
+							   false);
+					if (ret)
+						return ERR_PTR(ret);
+				}
+			}
+		}
+		clk->parent_names = (const char *const *)parent_names;
 	} else {
 		for (i = 0; i < init->num_parents; i++)
 			clk->parents[i] = clk_hw_to_clk(init->parent_hws[i]);

-- 
2.46.0