[PATCH v3 2/2] clk: scmi: add set/get_parent support

From: Peng Fan (OSS)
Date: Sun Oct 01 2023 - 00:34:24 EST


From: Peng Fan <peng.fan@xxxxxxx>

SCMI v3.2 adds set/get parent clock commands, so update the clk driver
to support them.

Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
---
drivers/clk/clk-scmi.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 49 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c
index 2e1337b511eb..5aaca674830f 100644
--- a/drivers/clk/clk-scmi.c
+++ b/drivers/clk/clk-scmi.c
@@ -24,6 +24,7 @@ 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)
@@ -78,6 +79,35 @@ 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 u8 scmi_clk_get_parent(struct clk_hw *hw)
+{
+ struct scmi_clk *clk = to_scmi_clk(hw);
+ u32 parent_id;
+ int ret;
+
+ ret = scmi_proto_clk_ops->parent_get(clk->ph, clk->id, &parent_id);
+ if (ret)
+ return 0;
+
+ return parent_id;
+}
+
+static int scmi_clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
+{
+ /*
+ * Suppose all the requested rates are supported, and let firmware
+ * to handle the left work.
+ */
+ return 0;
+}
+
static int scmi_clk_enable(struct clk_hw *hw)
{
struct scmi_clk *clk = to_scmi_clk(hw);
@@ -139,6 +169,9 @@ static const struct clk_ops scmi_clk_ops = {
.set_rate = scmi_clk_set_rate,
.prepare = scmi_clk_enable,
.unprepare = scmi_clk_disable,
+ .set_parent = scmi_clk_set_parent,
+ .get_parent = scmi_clk_get_parent,
+ .determine_rate = scmi_clk_determine_rate,
};

static const struct clk_ops scmi_atomic_clk_ops = {
@@ -148,6 +181,9 @@ static const struct clk_ops scmi_atomic_clk_ops = {
.enable = scmi_clk_atomic_enable,
.disable = scmi_clk_atomic_disable,
.is_enabled = scmi_clk_atomic_is_enabled,
+ .set_parent = scmi_clk_set_parent,
+ .get_parent = scmi_clk_get_parent,
+ .determine_rate = scmi_clk_determine_rate,
};

static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk,
@@ -158,9 +194,10 @@ 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,
+ .parent_data = sclk->parent_data,
};

sclk->hw.init = &init;
@@ -250,6 +287,17 @@ 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) {
+ sclk->parent_data = devm_kcalloc(dev, sclk->info->num_parents,
+ sizeof(*sclk->parent_data), GFP_KERNEL);
+
+ 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);

--
2.37.1