[PATCH v2 0/5] Support enabling interconnect path for GDSC for fixing Milos camcc

[PATCH v2 0/5] Support enabling interconnect path for GDSC for fixing Milos camcc

[Luca Weiss]

Some power domains like CAMSS_TOP_GDSC requires the enablement of the
multimedia NoC on newer SoCs like Milos.

Add support for getting an interconnect path as specified in the SoC
clock driver, and enabling/disabling that interconnect path when the
GDSC is being enabled/disabled.

Then specify that dependency in the camcc-milos driver and add it to the
dt-bindings and milos.dtsi.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
Changes in v2:
- Move icc_set_bw() calls to gdsc_toggle_logic() (Mike)
- Try to make dt-bindings commit message clearer
- Pick up tags
- Link to v1: https://lore.kernel.org/r/20260116-milos-camcc-icc-v1-0-400b7fcd156a@fairphone.com

---
Luca Weiss (5):
      interconnect: Add devm_of_icc_get_by_index() as exported API for users
      dt-bindings: clock: qcom,milos-camcc: Document interconnect path
      clk: qcom: gdsc: Support enabling interconnect path for power domain
      clk: qcom: camcc-milos: Declare icc path dependency for CAMSS_TOP_GDSC
      arm64: dts: qcom: milos: Add interconnects to camcc

 .../bindings/clock/qcom,milos-camcc.yaml           |  8 ++++++
 arch/arm64/boot/dts/qcom/milos.dtsi                |  3 ++
 drivers/clk/qcom/camcc-milos.c                     |  7 +++++
 drivers/clk/qcom/gdsc.c                            | 33 ++++++++++++++++++++++
 drivers/clk/qcom/gdsc.h                            |  5 ++++
 drivers/interconnect/core.c                        | 20 +++++++++++++
 include/linux/interconnect.h                       |  6 ++++
 7 files changed, 82 insertions(+)
---
base-commit: 9f5d28c2bae83e051ab7f807c819a634693ebffc
change-id: 20260116-milos-camcc-icc-d41bdff31ef8

Best regards,
--  
Luca Weiss <luca.weiss@fairphone.com>

[PATCH v2 1/5] interconnect: Add devm_of_icc_get_by_index() as exported API for users

[Luca Weiss]

Users can use devm version of of_icc_get_by_index() to benefit from
automatic resource release.

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
 drivers/interconnect/core.c  | 20 ++++++++++++++++++++
 include/linux/interconnect.h |  6 ++++++
 2 files changed, 26 insertions(+)

diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c
index 8569b78a1851..bc2e416dbcb2 100644
--- a/drivers/interconnect/core.c
+++ b/drivers/interconnect/core.c
@@ -443,6 +443,26 @@ struct icc_path *devm_of_icc_get(struct device *dev, const char *name)
 }
 EXPORT_SYMBOL_GPL(devm_of_icc_get);
 
+struct icc_path *devm_of_icc_get_by_index(struct device *dev, int idx)
+{
+	struct icc_path **ptr, *path;
+
+	ptr = devres_alloc(devm_icc_release, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return ERR_PTR(-ENOMEM);
+
+	path = of_icc_get_by_index(dev, idx);
+	if (!IS_ERR(path)) {
+		*ptr = path;
+		devres_add(dev, ptr);
+	} else {
+		devres_free(ptr);
+	}
+
+	return path;
+}
+EXPORT_SYMBOL_GPL(devm_of_icc_get_by_index);
+
 /**
  * of_icc_get_by_index() - get a path handle from a DT node based on index
  * @dev: device pointer for the consumer device
diff --git a/include/linux/interconnect.h b/include/linux/interconnect.h
index 4b12821528a6..75a32ad0482e 100644
--- a/include/linux/interconnect.h
+++ b/include/linux/interconnect.h
@@ -47,6 +47,7 @@ struct icc_path *of_icc_get(struct device *dev, const char *name);
 struct icc_path *devm_of_icc_get(struct device *dev, const char *name);
 int devm_of_icc_bulk_get(struct device *dev, int num_paths, struct icc_bulk_data *paths);
 struct icc_path *of_icc_get_by_index(struct device *dev, int idx);
+struct icc_path *devm_of_icc_get_by_index(struct device *dev, int idx);
 void icc_put(struct icc_path *path);
 int icc_enable(struct icc_path *path);
 int icc_disable(struct icc_path *path);
@@ -79,6 +80,11 @@ static inline struct icc_path *of_icc_get_by_index(struct device *dev, int idx)
 	return NULL;
 }
 
+static inline struct icc_path *devm_of_icc_get_by_index(struct device *dev, int idx)
+{
+	return NULL;
+}
+
 static inline void icc_put(struct icc_path *path)
 {
 }

-- 
2.54.0

[PATCH v2 2/5] dt-bindings: clock: qcom,milos-camcc: Document interconnect path

[Luca Weiss]

Document an interconnect path for camcc which needs to be enabled so
that the CAMSS_TOP_GDSC power domain can turn on successfully.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
 Documentation/devicetree/bindings/clock/qcom,milos-camcc.yaml | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/devicetree/bindings/clock/qcom,milos-camcc.yaml b/Documentation/devicetree/bindings/clock/qcom,milos-camcc.yaml
index f63149ecf3e1..707b25d2c11e 100644
--- a/Documentation/devicetree/bindings/clock/qcom,milos-camcc.yaml
+++ b/Documentation/devicetree/bindings/clock/qcom,milos-camcc.yaml
@@ -25,6 +25,10 @@ properties:
       - description: Sleep clock source
       - description: Camera AHB clock from GCC
 
+  interconnects:
+    items:
+      - description: Interconnect path to enable the MultiMedia NoC
+
 required:
   - compatible
   - clocks
@@ -37,12 +41,16 @@ unevaluatedProperties: false
 examples:
   - |
     #include <dt-bindings/clock/qcom,milos-gcc.h>
+    #include <dt-bindings/interconnect/qcom,icc.h>
+    #include <dt-bindings/interconnect/qcom,milos-rpmh.h>
     clock-controller@adb0000 {
         compatible = "qcom,milos-camcc";
         reg = <0x0adb0000 0x40000>;
         clocks = <&bi_tcxo_div2>,
                  <&sleep_clk>,
                  <&gcc GCC_CAMERA_AHB_CLK>;
+        interconnects = <&mmss_noc MASTER_CAMNOC_HF QCOM_ICC_TAG_ALWAYS
+                         &mmss_noc SLAVE_MNOC_HF_MEM_NOC QCOM_ICC_TAG_ALWAYS>;
         #clock-cells = <1>;
         #reset-cells = <1>;
         #power-domain-cells = <1>;

-- 
2.54.0

[PATCH v2 3/5] clk: qcom: gdsc: Support enabling interconnect path for power domain

[Luca Weiss]

On newer SoCs like Milos the CAMSS_TOP_GDSC power domains requires the
enablement of the multimedia NoC, otherwise the GDSC will be stuck on
'off'.

Add support for getting an interconnect path as specified in the SoC
clock driver, and enabling/disabling that interconnect path when the
GDSC is being enabled/disabled.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
icc_enable()/icc_disable() seems like a nice API but doesn't work
without setting the bandwidth first, so it's not very useful for this
driver, at least I couldn't figure out how to use it correctly.
---
 drivers/clk/qcom/gdsc.c | 33 +++++++++++++++++++++++++++++++++
 drivers/clk/qcom/gdsc.h |  5 +++++
 2 files changed, 38 insertions(+)

diff --git a/drivers/clk/qcom/gdsc.c b/drivers/clk/qcom/gdsc.c
index 95aa07120245..ee5f86ca50cb 100644
--- a/drivers/clk/qcom/gdsc.c
+++ b/drivers/clk/qcom/gdsc.c
@@ -7,6 +7,7 @@
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/export.h>
+#include <linux/interconnect.h>
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
 #include <linux/ktime.h>
@@ -147,6 +148,12 @@ static int gdsc_toggle_logic(struct gdsc *sc, enum gdsc_status status,
 			return ret;
 	}
 
+	if (status == GDSC_ON) {
+		ret = icc_set_bw(sc->icc_path, 1, 1);
+		if (ret)
+			goto err_disable_supply;
+	}
+
 	ret = gdsc_update_collapse_bit(sc, status == GDSC_OFF);
 
 	/* If disabling votable gdscs, don't poll on status */
@@ -177,6 +184,12 @@ static int gdsc_toggle_logic(struct gdsc *sc, enum gdsc_status status,
 	ret = gdsc_poll_status(sc, status);
 	WARN(ret, "%s status stuck at 'o%s'", sc->pd.name, status ? "ff" : "n");
 
+	if (!ret && status == GDSC_OFF) {
+		ret = icc_set_bw(sc->icc_path, 0, 0);
+		if (ret)
+			return ret;
+	}
+
 	if (!ret && status == GDSC_OFF && sc->rsupply) {
 		ret = regulator_disable(sc->rsupply);
 		if (ret < 0)
@@ -184,6 +197,12 @@ static int gdsc_toggle_logic(struct gdsc *sc, enum gdsc_status status,
 	}
 
 	return ret;
+
+err_disable_supply:
+	if (status == GDSC_ON && sc->rsupply)
+		regulator_disable(sc->rsupply);
+
+	return ret;
 }
 
 static inline int gdsc_deassert_reset(struct gdsc *sc)
@@ -584,6 +603,20 @@ int gdsc_register(struct gdsc_desc *desc,
 	if (!data->domains)
 		return -ENOMEM;
 
+	for (i = 0; i < num; i++) {
+		if (!scs[i] || !scs[i]->needs_icc)
+			continue;
+
+		scs[i]->icc_path = devm_of_icc_get_by_index(dev, scs[i]->icc_path_index);
+		if (IS_ERR(scs[i]->icc_path)) {
+			ret = PTR_ERR(scs[i]->icc_path);
+			if (ret != -ENODEV)
+				return ret;
+
+			scs[i]->icc_path = NULL;
+		}
+	}
+
 	for (i = 0; i < num; i++) {
 		if (!scs[i] || !scs[i]->supply)
 			continue;
diff --git a/drivers/clk/qcom/gdsc.h b/drivers/clk/qcom/gdsc.h
index dd843e86c05b..92ff6bcce7b1 100644
--- a/drivers/clk/qcom/gdsc.h
+++ b/drivers/clk/qcom/gdsc.h
@@ -9,6 +9,7 @@
 #include <linux/err.h>
 #include <linux/pm_domain.h>
 
+struct icc_path;
 struct regmap;
 struct regulator;
 struct reset_controller_dev;
@@ -74,6 +75,10 @@ struct gdsc {
 
 	const char 			*supply;
 	struct regulator		*rsupply;
+
+	bool				needs_icc;
+	unsigned int			icc_path_index;
+	struct icc_path			*icc_path;
 };
 
 struct gdsc_desc {

-- 
2.54.0

[PATCH v2 4/5] clk: qcom: camcc-milos: Declare icc path dependency for CAMSS_TOP_GDSC

[Luca Weiss]

This GDSC requires an interconnect path to be enabled, otherwise the
GDSC will be stuck on 'off' and can't be enabled.

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
 drivers/clk/qcom/camcc-milos.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/clk/qcom/camcc-milos.c b/drivers/clk/qcom/camcc-milos.c
index 409d47098c10..579b71e0e089 100644
--- a/drivers/clk/qcom/camcc-milos.c
+++ b/drivers/clk/qcom/camcc-milos.c
@@ -30,6 +30,11 @@ enum {
 	DT_IFACE,
 };
 
+/* Need to match the order of interconnects in DT binding */
+enum {
+	DT_ICC_TOP_GDSC,
+};
+
 enum {
 	P_BI_TCXO,
 	P_CAM_CC_PLL0_OUT_EVEN,
@@ -1971,6 +1976,8 @@ static struct gdsc cam_cc_camss_top_gdsc = {
 	},
 	.pwrsts = PWRSTS_OFF_ON,
 	.flags = POLL_CFG_GDSCR | RETAIN_FF_ENABLE,
+	.needs_icc = true,
+	.icc_path_index = DT_ICC_TOP_GDSC,
 };
 
 static struct clk_regmap *cam_cc_milos_clocks[] = {

-- 
2.54.0

[PATCH v2 5/5] arm64: dts: qcom: milos: Add interconnects to camcc

[Luca Weiss]

The CAMSS_TOP_GDSC inside camcc requires an interconnect path to be
enabled, otherwise the GDSC will be stuck on 'off' and can't be enabled.

Add the interconnect path so that this requirement can be satisfied by
the kernel.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
 arch/arm64/boot/dts/qcom/milos.dtsi | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/milos.dtsi b/arch/arm64/boot/dts/qcom/milos.dtsi
index 4a64a98a434b..80208bc33730 100644
--- a/arch/arm64/boot/dts/qcom/milos.dtsi
+++ b/arch/arm64/boot/dts/qcom/milos.dtsi
@@ -1923,6 +1923,9 @@ camcc: clock-controller@adb0000 {
 				 <&sleep_clk>,
 				 <&gcc GCC_CAMERA_AHB_CLK>;
 
+			interconnects = <&mmss_noc MASTER_CAMNOC_HF QCOM_ICC_TAG_ALWAYS
+					 &mmss_noc SLAVE_MNOC_HF_MEM_NOC QCOM_ICC_TAG_ALWAYS>;
+
 			#clock-cells = <1>;
 			#reset-cells = <1>;
 			#power-domain-cells = <1>;

-- 
2.54.0

Re: [PATCH v2 2/5] dt-bindings: clock: qcom,milos-camcc: Document interconnect path

[Krzysztof Kozlowski]

On Fri, May 01, 2026 at 11:18:30AM +0200, Luca Weiss wrote:
> Document an interconnect path for camcc which needs to be enabled so
> that the CAMSS_TOP_GDSC power domain can turn on successfully.
> 
> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>

Best regards,
Krzysztof

Re: [PATCH v2 5/5] arm64: dts: qcom: milos: Add interconnects to camcc

[Konrad Dybcio]

On 5/1/26 11:18 AM, Luca Weiss wrote:
> The CAMSS_TOP_GDSC inside camcc requires an interconnect path to be
> enabled, otherwise the GDSC will be stuck on 'off' and can't be enabled.
> 
> Add the interconnect path so that this requirement can be satisfied by
> the kernel.
> 
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
> ---

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>

Konrad