[PATCH v3 2/5] clk: scmi: Add support for state control restricted clocks

From: Cristian Marussi
Date: Mon Apr 15 2024 - 12:38:05 EST


Some exposed SCMI Clocks could be marked as non-supporting state changes.
Configure a clk_ops descriptor which does not provide the state change
callbacks for such clocks when registering with CLK framework.

CC: Michael Turquette <mturquette@xxxxxxxxxxxx>
CC: Stephen Boyd <sboyd@xxxxxxxxxx>
CC: linux-clk@xxxxxxxxxxxxxxx
Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx>
---
v2 -> v3
- using SCMI_CLK_STATE_CTRL_SUPPORTED instead of _FORBIDDEN
---
drivers/clk/clk-scmi.c | 22 +++++++++++++++-------
1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c
index 4b6c43d7f5f3..e70708573965 100644
--- a/drivers/clk/clk-scmi.c
+++ b/drivers/clk/clk-scmi.c
@@ -19,6 +19,7 @@

enum scmi_clk_feats {
SCMI_CLK_ATOMIC_SUPPORTED,
+ SCMI_CLK_STATE_CTRL_SUPPORTED,
SCMI_CLK_FEATS_COUNT
};

@@ -230,15 +231,19 @@ scmi_clk_ops_alloc(struct device *dev, unsigned long feats_key)
* only the prepare/unprepare API, as allowed by the clock framework
* when atomic calls are not available.
*/
- if (feats_key & BIT(SCMI_CLK_ATOMIC_SUPPORTED)) {
- ops->enable = scmi_clk_atomic_enable;
- ops->disable = scmi_clk_atomic_disable;
- ops->is_enabled = scmi_clk_atomic_is_enabled;
- } else {
- ops->prepare = scmi_clk_enable;
- ops->unprepare = scmi_clk_disable;
+ if (feats_key & BIT(SCMI_CLK_STATE_CTRL_SUPPORTED)) {
+ if (feats_key & BIT(SCMI_CLK_ATOMIC_SUPPORTED)) {
+ ops->enable = scmi_clk_atomic_enable;
+ ops->disable = scmi_clk_atomic_disable;
+ } else {
+ ops->prepare = scmi_clk_enable;
+ ops->unprepare = scmi_clk_disable;
+ }
}

+ if (feats_key & BIT(SCMI_CLK_ATOMIC_SUPPORTED))
+ ops->is_enabled = scmi_clk_atomic_is_enabled;
+
/* Rate ops */
ops->recalc_rate = scmi_clk_recalc_rate;
ops->round_rate = scmi_clk_round_rate;
@@ -294,6 +299,9 @@ scmi_clk_ops_select(struct scmi_clk *sclk, bool atomic_capable,
if (atomic_capable && ci->enable_latency <= atomic_threshold_us)
feats_key |= BIT(SCMI_CLK_ATOMIC_SUPPORTED);

+ if (!ci->state_ctrl_forbidden)
+ feats_key |= BIT(SCMI_CLK_STATE_CTRL_SUPPORTED);
+
if (WARN_ON(feats_key >= db_size))
return NULL;

--
2.44.0