regulator: spacemit-p1: Support board power tree

Merge series from Guodong Xu <guodong@riscstar.com>:

Patch 1, 2 and 3 (previously 2-4) enable flexible power tree
configurations for the SpacemiT P1 PMIC. Hardcoded supply assumptions
are replaced with explicit devicetree properties. PMIC supply connections
are board-design decisions. Moving this to DT allows supporting varied
topologies without driver modifications.

The supply binding change is an ABI change. The breakage is acceptable:
Yixun Lan checked the DTS tree queued for v6.20 and found no consumers
of the P1/PMIC regulator yet [1]. For the two K1 boards in-tree
(BPI-F3 and Jupiter), initial power settings come from boot firmware and
a probe failure of pmic node "spacemit,p1" has minimal impact.

In v4, the old "vin-supply" property is dropped from the binding
document as the updated driver no longer parses it and there is no
fallback logic. Only the per-rail names ("vin1-supply", "vin2-supply",
...) are supported going forward.

Intermittent dtbs_check warnings are expected while the binding and DTS
changes land through different trees, but will resolve once both are
merged.

Link: https://lore.kernel.org/lkml/20260125110333-GYD71302@gentoo.org/ [1]

2 files changed, 61 insertions, 13 deletions

diff --git a/Documentation/devicetree/bindings/mfd/spacemit,p1.yaml b/Documentation/devicetree/bindings/mfd/spacemit,p1.yaml
index c6593ac6ef6a..c67b1c6e4e4f 100644
--- a/Documentation/devicetree/bindings/mfd/spacemit,p1.yaml
+++ b/Documentation/devicetree/bindings/mfd/spacemit,p1.yaml
@@ -27,8 +27,41 @@ properties:
   interrupts:
     maxItems: 1
 
-  vin-supply:
-    description: Input supply phandle.
+  vin1-supply:
+    description:
+      Power supply for BUCK1. Required if BUCK1 is defined.
+
+  vin2-supply:
+    description:
+      Power supply for BUCK2. Required if BUCK2 is defined.
+
+  vin3-supply:
+    description:
+      Power supply for BUCK3. Required if BUCK3 is defined.
+
+  vin4-supply:
+    description:
+      Power supply for BUCK4. Required if BUCK4 is defined.
+
+  vin5-supply:
+    description:
+      Power supply for BUCK5. Required if BUCK5 is defined.
+
+  vin6-supply:
+    description:
+      Power supply for BUCK6. Required if BUCK6 is defined.
+
+  aldoin-supply:
+    description:
+      Power supply for ALDO1-4. Required if any are defined.
+
+  dldoin1-supply:
+    description:
+      Power supply for DLDO1-4. Required if any are defined.
+
+  dldoin2-supply:
+    description:
+      Power supply for DLDO5-7. Required if any are defined.
 
   regulators:
     type: object
@@ -58,6 +91,10 @@ examples:
             compatible = "spacemit,p1";
             reg = <0x41>;
             interrupts = <64>;
+            vin1-supply = <&reg_vcc_5v>;
+            vin5-supply = <&reg_vcc_5v>;
+            aldoin-supply = <&reg_vcc_5v>;
+            dldoin1-supply = <&buck5>;
 
             regulators {
                 buck1 {
@@ -68,6 +105,14 @@ examples:
                     regulator-always-on;
                 };
 
+                buck5: buck5 {
+                    regulator-name = "buck5";
+                    regulator-min-microvolt = <500000>;
+                    regulator-max-microvolt = <3450000>;
+                    regulator-ramp-delay = <5000>;
+                    regulator-always-on;
+                };
+
                 aldo1 {
                     regulator-name = "aldo1";
                     regulator-min-microvolt = <500000>;
diff --git a/drivers/regulator/spacemit-p1.c b/drivers/regulator/spacemit-p1.c
index 2b585ba01a93..57e6e00a73fa 100644
--- a/drivers/regulator/spacemit-p1.c
+++ b/drivers/regulator/spacemit-p1.c
@@ -87,13 +87,16 @@ static const struct linear_range p1_ldo_ranges[] = {
 	}
 
 #define P1_BUCK_DESC(_n) \
-	P1_REG_DESC(BUCK, buck, _n, "vin", 0x47, BUCK_MASK, 255, p1_buck_ranges)
+	P1_REG_DESC(BUCK, buck, _n, "vin" #_n, 0x47, BUCK_MASK, 255, p1_buck_ranges)
 
 #define P1_ALDO_DESC(_n) \
-	P1_REG_DESC(ALDO, aldo, _n, "vin", 0x5b, LDO_MASK, 128, p1_ldo_ranges)
+	P1_REG_DESC(ALDO, aldo, _n, "aldoin", 0x5b, LDO_MASK, 128, p1_ldo_ranges)
 
-#define P1_DLDO_DESC(_n) \
-	P1_REG_DESC(DLDO, dldo, _n, "buck5", 0x67, LDO_MASK, 128, p1_ldo_ranges)
+#define P1_DLDO1_DESC(_n) \
+	P1_REG_DESC(DLDO, dldo, _n, "dldoin1", 0x67, LDO_MASK, 128, p1_ldo_ranges)
+
+#define P1_DLDO2_DESC(_n) \
+	P1_REG_DESC(DLDO, dldo, _n, "dldoin2", 0x67, LDO_MASK, 128, p1_ldo_ranges)
 
 static const struct regulator_desc p1_regulator_desc[] = {
 	P1_BUCK_DESC(1),
@@ -108,13 +111,13 @@ static const struct regulator_desc p1_regulator_desc[] = {
 	P1_ALDO_DESC(3),
 	P1_ALDO_DESC(4),
 
-	P1_DLDO_DESC(1),
-	P1_DLDO_DESC(2),
-	P1_DLDO_DESC(3),
-	P1_DLDO_DESC(4),
-	P1_DLDO_DESC(5),
-	P1_DLDO_DESC(6),
-	P1_DLDO_DESC(7),
+	P1_DLDO1_DESC(1),
+	P1_DLDO1_DESC(2),
+	P1_DLDO1_DESC(3),
+	P1_DLDO1_DESC(4),
+	P1_DLDO2_DESC(5),
+	P1_DLDO2_DESC(6),
+	P1_DLDO2_DESC(7),
 };
 
 static int p1_regulator_probe(struct platform_device *pdev)