[PATCH v2 25/33] clk: arm_scmi: implement clock parent setting

[Sascha Hauer]

This adds support for getting/setting the clk parents in the SCMI clk
driver.

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 drivers/clk/clk-scmi.c | 80 +++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 72 insertions(+), 8 deletions(-)

diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c
index 5c9f61ae0b6f94da104cda682e8b399fc4f9c84e..62228d7ba2c12b6bf4ae41dff4aa4553fd3e325e 100644
--- a/drivers/clk/clk-scmi.c
+++ b/drivers/clk/clk-scmi.c
@@ -20,6 +20,7 @@ struct scmi_clk {
 	struct clk_hw hw;
 	const struct scmi_clock_info *info;
 	const struct scmi_protocol_handle *ph;
+	struct clk_parent_data *parent_data;
 };
 
 #define to_scmi_clk(clk) container_of(clk, struct scmi_clk, hw)
@@ -74,6 +75,34 @@ static int scmi_clk_set_rate(struct clk_hw *hw, unsigned long rate,
 	return scmi_proto_clk_ops->rate_set(clk->ph, clk->id, rate);
 }
 
+static int scmi_clk_set_parent(struct clk_hw *hw, u8 parent_index)
+{
+	struct scmi_clk *clk = to_scmi_clk(hw);
+
+	return scmi_proto_clk_ops->parent_set(clk->ph, clk->id, parent_index);
+}
+
+static int scmi_clk_get_parent(struct clk_hw *hw)
+{
+	struct scmi_clk *clk = to_scmi_clk(hw);
+	u32 parent_id, p_idx;
+	int ret;
+
+	ret = scmi_proto_clk_ops->parent_get(clk->ph, clk->id, &parent_id);
+	if (ret)
+		return 0;
+
+	for (p_idx = 0; p_idx < clk->info->num_parents; p_idx++) {
+		if (clk->parent_data[p_idx].index == parent_id)
+			break;
+	}
+
+	if (p_idx == clk->info->num_parents)
+		return 0;
+
+	return p_idx;
+}
+
 static int scmi_clk_enable(struct clk_hw *hw)
 {
 	struct scmi_clk *clk = to_scmi_clk(hw);
@@ -121,6 +150,8 @@ static const struct clk_ops scmi_clk_ops = {
 	.set_rate = scmi_clk_set_rate,
 	.enable = scmi_clk_enable,
 	.disable = scmi_clk_disable,
+	.set_parent = scmi_clk_set_parent,
+	.get_parent = scmi_clk_get_parent,
 };
 
 static const struct clk_ops scmi_atomic_clk_ops = {
@@ -129,6 +160,8 @@ static const struct clk_ops scmi_atomic_clk_ops = {
 	.set_rate = scmi_clk_set_rate,
 	.enable = scmi_clk_atomic_enable,
 	.disable = scmi_clk_atomic_disable,
+	.set_parent = scmi_clk_set_parent,
+	.get_parent = scmi_clk_get_parent,
 };
 
 static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk,
@@ -136,12 +169,22 @@ static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk,
 {
 	struct clk_init_data init = {
 		.flags = CLK_GET_RATE_NOCACHE,
-	
-		.num_parents = 0,
+		.num_parents = sclk->info->num_parents,
 		.ops = scmi_ops,
 		.name = sclk->info->name,
 	};
 
+	if (sclk->info->num_parents > 0) {
+		init.parent_hws = devm_kcalloc(dev, sclk->info->num_parents,
+					       sizeof(void *), GFP_KERNEL);
+		if (!init.parent_hws)
+			return -ENOMEM;
+
+		for (int i = 0; i < sclk->info->num_parents; i++) {
+			init.parent_hws[i] = sclk->parent_data[i].hw;
+		}
+	}
+
 	sclk->hw.init = &init;
 	return clk_hw_register(dev, &sclk->hw);
 }
@@ -157,6 +200,8 @@ static int scmi_clocks_probe(struct scmi_device *sdev)
 	struct device_node *np = dev->of_node;
 	const struct scmi_handle *handle = sdev->handle;
 	struct scmi_protocol_handle *ph;
+	struct scmi_clk *sclks;
+	int ret;
 
 	if (!handle)
 		return -ENODEV;
@@ -182,13 +227,17 @@ static int scmi_clocks_probe(struct scmi_device *sdev)
 
 	is_atomic = handle->is_transport_atomic(handle, &atomic_threshold);
 
+	sclks = devm_kzalloc(dev, sizeof(*sclks) * count, GFP_KERNEL);
+
 	for (idx = 0; idx < count; idx++) {
-		struct scmi_clk *sclk;
-		const struct clk_ops *scmi_ops;
+		struct scmi_clk *sclk = &sclks[idx];
 
-		sclk = devm_kzalloc(dev, sizeof(*sclk), GFP_KERNEL);
-		if (!sclk)
-			return -ENOMEM;
+		hws[idx] = &sclk->hw;
+	}
+
+	for (idx = 0; idx < count; idx++) {
+		struct scmi_clk *sclk = &sclks[idx];
+		const struct clk_ops *scmi_ops;
 
 		sclk->info = scmi_proto_clk_ops->info_get(ph, idx);
 		if (!sclk->info) {
@@ -210,9 +259,25 @@ static int scmi_clocks_probe(struct scmi_device *sdev)
 		else
 			scmi_ops = &scmi_clk_ops;
 
+		/* Initialize clock parent data. */
+		if (sclk->info->num_parents > 0) {
+			u32 parent_id;
+
+			sclk->parent_data = devm_kcalloc(dev, sclk->info->num_parents,
+							 sizeof(*sclk->parent_data), GFP_KERNEL);
+			if (!sclk->parent_data)
+				return -ENOMEM;
+
+			for (int i = 0; i < sclk->info->num_parents; i++) {
+				sclk->parent_data[i].index = sclk->info->parents[i];
+				sclk->parent_data[i].hw = hws[sclk->info->parents[i]];
+			}
+		}
+
 		err = scmi_clk_ops_init(dev, sclk, scmi_ops);
 		if (err) {
 			dev_err(dev, "failed to register clock %d\n", idx);
+			devm_kfree(dev, sclk->parent_data);
 			devm_kfree(dev, sclk);
 			hws[idx] = NULL;
 		} else {
@@ -220,7 +285,6 @@ static int scmi_clocks_probe(struct scmi_device *sdev)
 				sclk->info->name,
 				scmi_ops == &scmi_atomic_clk_ops ?
 				" (atomic ops)" : "");
-			hws[idx] = &sclk->hw;
 		}
 	}
 

-- 
2.39.5