[PATCH v5 2/4] clk: sunxi-ng: div: add read-only operation support
From: Jerome Brunet
Date: Fri Jul 17 2026 - 11:27:45 EST
Add support for sunxi-ng read-only dividers. This will be
useful to the a733 oscillator detection logic.
Reviewed-by: Chen-Yu Tsai <wens@xxxxxxxxxx>
Signed-off-by: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
---
drivers/clk/sunxi-ng/ccu_div.c | 30 ++++++++++++++++++++++++++++--
drivers/clk/sunxi-ng/ccu_div.h | 1 +
drivers/clk/sunxi-ng/ccu_mux.c | 2 +-
drivers/clk/sunxi-ng/ccu_mux.h | 4 ++++
4 files changed, 34 insertions(+), 3 deletions(-)
diff --git a/drivers/clk/sunxi-ng/ccu_div.c b/drivers/clk/sunxi-ng/ccu_div.c
index 62d680ccb524..93cb4cb93abe 100644
--- a/drivers/clk/sunxi-ng/ccu_div.c
+++ b/drivers/clk/sunxi-ng/ccu_div.c
@@ -20,8 +20,22 @@ static int ccu_div_determine_rate_helper(struct ccu_mux_internal *mux,
if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
req->rate *= cd->fixed_post_div;
- ret = divider_determine_rate(&cd->common.hw, req, cd->div.table,
- cd->div.width, cd->div.flags);
+ if (cd->div.flags & CLK_DIVIDER_READ_ONLY) {
+ unsigned long val;
+ u32 reg;
+
+ reg = readl(cd->common.base + cd->common.reg);
+ val = reg >> cd->div.shift;
+ val &= (1 << cd->div.width) - 1;
+
+ ret = divider_ro_determine_rate(&cd->common.hw, req, cd->div.table,
+ cd->div.width, cd->div.flags, val);
+
+ } else {
+ ret = divider_determine_rate(&cd->common.hw, req, cd->div.table,
+ cd->div.width, cd->div.flags);
+ }
+
if (ret)
return ret;
@@ -143,3 +157,15 @@ const struct clk_ops ccu_div_ops = {
.set_rate = ccu_div_set_rate,
};
EXPORT_SYMBOL_NS_GPL(ccu_div_ops, "SUNXI_CCU");
+
+const struct clk_ops ccu_rodiv_ops = {
+ .disable = ccu_div_disable,
+ .enable = ccu_div_enable,
+ .is_enabled = ccu_div_is_enabled,
+
+ .get_parent = ccu_div_get_parent,
+
+ .determine_rate = ccu_div_determine_rate,
+ .recalc_rate = ccu_div_recalc_rate,
+};
+EXPORT_SYMBOL_NS_GPL(ccu_rodiv_ops, "SUNXI_CCU");
diff --git a/drivers/clk/sunxi-ng/ccu_div.h b/drivers/clk/sunxi-ng/ccu_div.h
index be00b3277e97..a30a92780a05 100644
--- a/drivers/clk/sunxi-ng/ccu_div.h
+++ b/drivers/clk/sunxi-ng/ccu_div.h
@@ -300,5 +300,6 @@ static inline struct ccu_div *hw_to_ccu_div(struct clk_hw *hw)
}
extern const struct clk_ops ccu_div_ops;
+extern const struct clk_ops ccu_rodiv_ops;
#endif /* _CCU_DIV_H_ */
diff --git a/drivers/clk/sunxi-ng/ccu_mux.c b/drivers/clk/sunxi-ng/ccu_mux.c
index 75ec3457324c..905570375711 100644
--- a/drivers/clk/sunxi-ng/ccu_mux.c
+++ b/drivers/clk/sunxi-ng/ccu_mux.c
@@ -67,7 +67,7 @@ unsigned long ccu_mux_helper_apply_prediv(struct ccu_common *common,
return parent_rate / ccu_mux_get_prediv(common, cm, parent_index);
}
-static unsigned long ccu_mux_helper_unapply_prediv(struct ccu_common *common,
+unsigned long ccu_mux_helper_unapply_prediv(struct ccu_common *common,
struct ccu_mux_internal *cm,
int parent_index,
unsigned long parent_rate)
diff --git a/drivers/clk/sunxi-ng/ccu_mux.h b/drivers/clk/sunxi-ng/ccu_mux.h
index c94a4bde5d01..272a2c36a8f2 100644
--- a/drivers/clk/sunxi-ng/ccu_mux.h
+++ b/drivers/clk/sunxi-ng/ccu_mux.h
@@ -134,6 +134,10 @@ unsigned long ccu_mux_helper_apply_prediv(struct ccu_common *common,
struct ccu_mux_internal *cm,
int parent_index,
unsigned long parent_rate);
+unsigned long ccu_mux_helper_unapply_prediv(struct ccu_common *common,
+ struct ccu_mux_internal *cm,
+ int parent_index,
+ unsigned long parent_rate);
int ccu_mux_helper_determine_rate(struct ccu_common *common,
struct ccu_mux_internal *cm,
struct clk_rate_request *req,
--
2.47.3