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

Cristian Marussi
2024-03-25T21:01:00Z

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@baylibre.com>
CC: Stephen Boyd <sboyd@kernel.org>
CC: linux-clk@vger.kernel.org
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
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