[PATCH v2 5/5] clk: scmi: Add support for get/set duty_cycle operations

[Cristian Marussi]

Provide the CLK framework callbacks related to get/set clock duty cycle if
the related SCMI clock supports OEM extended configurations.

CC: Michael Turquette <mturquette@xxxxxxxxxxxx>
CC: Stephen Boyd <sboyd@xxxxxxxxxx>
CC: linux-clk@xxxxxxxxxxxxxxx
Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx>
---
 drivers/clk/clk-scmi.c | 49 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c
index 87e968b6c095..86ef7c553ddd 100644
--- a/drivers/clk/clk-scmi.c
+++ b/drivers/clk/clk-scmi.c
@@ -21,6 +21,7 @@ enum scmi_clk_feats {
 	SCMI_CLK_STATE_CTRL_FORBIDDEN,
 	SCMI_CLK_RATE_CTRL_FORBIDDEN,
 	SCMI_CLK_PARENT_CTRL_FORBIDDEN,
+	SCMI_CLK_DUTY_CYCLE_SUPPORTED,
 	SCMI_CLK_MAX_FEATS
 };
 
@@ -169,6 +170,45 @@ static int scmi_clk_atomic_is_enabled(struct clk_hw *hw)
 	return !!enabled;
 }
 
+static int scmi_clk_get_duty_cycle(struct clk_hw *hw, struct clk_duty *duty)
+{
+	int ret;
+	u32 val;
+	struct scmi_clk *clk = to_scmi_clk(hw);
+
+	ret = scmi_proto_clk_ops->config_oem_get(clk->ph, clk->id,
+						 SCMI_CLOCK_CFG_DUTY_CYCLE,
+						 &val, NULL, false);
+	if (!ret) {
+		duty->num = val;
+		duty->den = 100;
+	} else {
+		dev_warn(clk->dev,
+			 "Failed to get duty cycle for clock ID %d\n", clk->id);
+	}
+
+	return ret;
+}
+
+static int scmi_clk_set_duty_cycle(struct clk_hw *hw, struct clk_duty *duty)
+{
+	int ret;
+	u32 val;
+	struct scmi_clk *clk = to_scmi_clk(hw);
+
+	/* SCMI OEM Duty Cycle is expressed as a percentage */
+	val = (duty->num * 100) / duty->den;
+	ret = scmi_proto_clk_ops->config_oem_set(clk->ph, clk->id,
+						 SCMI_CLOCK_CFG_DUTY_CYCLE,
+						 val, false);
+	if (ret)
+		dev_warn(clk->dev,
+			 "Failed to set duty cycle(%u/%u) for clock ID %d\n",
+			 duty->num, duty->den, clk->id);
+
+	return ret;
+}
+
 static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk,
 			     const struct clk_ops *scmi_ops)
 {
@@ -258,6 +298,12 @@ scmi_clk_ops_alloc(struct device *dev, unsigned long feats_key)
 	if (!(feats_key & BIT(SCMI_CLK_PARENT_CTRL_FORBIDDEN)))
 		ops->set_parent = scmi_clk_set_parent;
 
+	/* Duty cycle */
+	if (feats_key & BIT(SCMI_CLK_DUTY_CYCLE_SUPPORTED)) {
+		ops->get_duty_cycle = scmi_clk_get_duty_cycle;
+		ops->set_duty_cycle = scmi_clk_set_duty_cycle;
+	}
+
 	return ops;
 }
 
@@ -306,6 +352,9 @@ scmi_clk_ops_select(struct scmi_clk *sclk, bool atomic_capable,
 	if (ci->parent_ctrl_forbidden)
 		feats_key |= BIT(SCMI_CLK_PARENT_CTRL_FORBIDDEN);
 
+	if (ci->extended_config)
+		feats_key |= BIT(SCMI_CLK_DUTY_CYCLE_SUPPORTED);
+
 	/* Lookup previously allocated ops */
 	ops = clk_ops_db[feats_key];
 	if (!ops) {
-- 
2.44.0