[PATCH v6 0/3] Add OF support for Microchip emc2305 fan controller

[PATCH v6 0/3] Add OF support for Microchip emc2305 fan controller

[florin.leotescu]

From: Florin Leotescu <florin.leotescu@nxp.com>

This patch series add initial OF support for Microchip emc2305 fan controller.

Changes since v5:
- Corrected blank line as recommended by Krzysztof Kozlowski.
- Removed pwms property from required list as Guenter Roeck suggested.
  The pwms should not be mandatory as the driver works fine with defaults settings.

Changes since v4:
- Corrected quotes to have a consistent definition.
- Corrected DTS coding style as recommended by Krzysztof Kozlowski.
- Updated pwms phandle to include pwm frequency, pwm polarity and pwm output,
  as recommended by Guenter Roeck and skipped the pwm channel as recommended by Krzysztof Kozlowski.
- Documented the pwms args in #pwm-cells description.
- Updated pwms phandle in dt-binding example to include pwm frequency and 
  use PWM_POLARITY_INVERTED macro to inverse the PWM polarity. 

Changes since v3:
- Removed thermal_cooling_device_register_fail label since is no longer needed
  and replaced goto with imediate return, as recommended by Guenter Roeck. 
- Redefined compatible property in dt-binding, as recommended by Frank Li.
- Updated driver of compatible list.
- Renamed node name in the dt-binding example, as recommended by Connor Dooley.
- Corrected dt-binding commit subject.
- Added dt-binding fan descriptions and $ref to fan schema, 
  as Connor Dooley & Krzysztof Kozlowski recommended.
  Used similar as on maxim,max6639 and nuvoton,nct7363. 
- Updated dt-binding example.

Changes since v2:
- Removed the introduction of new properties for now and we only 
  enable basic OF support.
- Link to previous version: 
  https://lore.kernel.org/linux-arm-kernel/20250219133221.2641041-3-florin.leotescu@oss.nxp.com/T/


Florin Leotescu (3):
  dt-bindings: hwmon: Add Microchip emc2305 support
  hwmon: emc2305: Add OF support
  hwmon: emc2305: Use devm_thermal_of_cooling_device_register

 .../bindings/hwmon/microchip,emc2305.yaml     | 110 ++++++++++++++++++
 drivers/hwmon/emc2305.c                       |  38 ++----
 2 files changed, 120 insertions(+), 28 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/hwmon/microchip,emc2305.yaml

-- 
2.34.1

[PATCH v6 1/3] dt-bindings: hwmon: Add Microchip emc2305 support

[florin.leotescu]

From: Florin Leotescu <florin.leotescu@nxp.com>

Introduce yaml schema for Microchip emc2305 pwm fan controller.

Signed-off-by: Florin Leotescu <florin.leotescu@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
 .../bindings/hwmon/microchip,emc2305.yaml     | 110 ++++++++++++++++++
 1 file changed, 110 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwmon/microchip,emc2305.yaml

diff --git a/Documentation/devicetree/bindings/hwmon/microchip,emc2305.yaml b/Documentation/devicetree/bindings/hwmon/microchip,emc2305.yaml
new file mode 100644
index 000000000000..79081c116274
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/microchip,emc2305.yaml
@@ -0,0 +1,110 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwmon/microchip,emc2305.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Microchip EMC2305 SMBus compliant PWM fan controller
+
+maintainers:
+  - Michael Shych <michaelsh@nvidia.com>
+
+description:
+  Microchip EMC2301/2/3/5 pwm controller which supports
+  up to five programmable fan control circuits.
+
+properties:
+  compatible:
+    oneOf:
+      - enum:
+          - microchip,emc2305
+      - items:
+          - enum:
+              - microchip,emc2303
+              - microchip,emc2302
+              - microchip,emc2301
+          - const: microchip,emc2305
+
+  reg:
+    maxItems: 1
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+  '#pwm-cells':
+    const: 3
+    description: |
+      Number of cells in a PWM specifier.
+      - cell 0: The PWM frequency
+      - cell 1: The PWM polarity: 0 or PWM_POLARITY_INVERTED
+      - cell 2: The PWM output config:
+           - 0 (Open-Drain)
+           - 1 (Push-Pull)
+
+patternProperties:
+  '^fan@[0-4]$':
+    $ref: fan-common.yaml#
+    unevaluatedProperties: false
+    properties:
+      reg:
+        description:
+          The fan number used to determine the associated PWM channel.
+
+    required:
+      - reg
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/pwm/pwm.h>
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        fan_controller: fan-controller@2f {
+            compatible = "microchip,emc2305";
+            reg = <0x2f>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+            #pwm-cells = <3>;
+
+            fan@0 {
+                reg = <0x0>;
+                pwms = <&fan_controller 26000 PWM_POLARITY_INVERTED 1>;
+                #cooling-cells = <2>;
+            };
+
+            fan@1 {
+                reg = <0x1>;
+                pwms = <&fan_controller 26000 0 1>;
+                #cooling-cells = <2>;
+            };
+
+            fan@2 {
+                reg = <0x2>;
+                pwms = <&fan_controller 26000 0 1>;
+                #cooling-cells = <2>;
+            };
+
+            fan@3 {
+                reg = <0x3>;
+                pwms = <&fan_controller 26000 0 1>;
+                #cooling-cells = <2>;
+            };
+
+            fan@4 {
+                reg = <0x4>;
+                pwms = <&fan_controller 26000 0 1>;
+                #cooling-cells = <2>;
+            };
+        };
+    };
+...
-- 
2.34.1

[PATCH v6 2/3] hwmon: emc2305: Add OF support

[florin.leotescu]

From: Florin Leotescu <florin.leotescu@nxp.com>

Introduce OF support for Microchip emc2305 pwm fan controller.

Signed-off-by: Florin Leotescu <florin.leotescu@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/hwmon/emc2305.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/hwmon/emc2305.c b/drivers/hwmon/emc2305.c
index 4d39fbd83769..f8a4c76fcadd 100644
--- a/drivers/hwmon/emc2305.c
+++ b/drivers/hwmon/emc2305.c
@@ -607,9 +607,16 @@ static void emc2305_remove(struct i2c_client *client)
 		emc2305_unset_tz(dev);
 }
 
+static const struct of_device_id of_emc2305_match_table[] = {
+	{ .compatible = "microchip,emc2305", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, of_emc2305_match_table);
+
 static struct i2c_driver emc2305_driver = {
 	.driver = {
 		.name = "emc2305",
+		.of_match_table = of_emc2305_match_table,
 	},
 	.probe = emc2305_probe,
 	.remove	  = emc2305_remove,
-- 
2.34.1

[PATCH v6 3/3] hwmon: emc2305: Use devm_thermal_of_cooling_device_register

[florin.leotescu]

From: Florin Leotescu <florin.leotescu@nxp.com>

Prepare the emc2305 driver to use configuration from Device Tree nodes.
Switch to devm_thermal_of_cooling_device_register to simplify the
cleanup procedure, allowing the removal of emc2305_unset_tz and
emc2305_remove, which are no longer needed.

Signed-off-by: Florin Leotescu <florin.leotescu@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/hwmon/emc2305.c | 33 ++++-----------------------------
 1 file changed, 4 insertions(+), 29 deletions(-)

diff --git a/drivers/hwmon/emc2305.c b/drivers/hwmon/emc2305.c
index f8a4c76fcadd..234c54956a4b 100644
--- a/drivers/hwmon/emc2305.c
+++ b/drivers/hwmon/emc2305.c
@@ -112,8 +112,6 @@ static char *emc2305_fan_name[] = {
 	"emc2305_fan5",
 };
 
-static void emc2305_unset_tz(struct device *dev);
-
 static int emc2305_get_max_channel(const struct emc2305_data *data)
 {
 	return data->pwm_num;
@@ -293,8 +291,9 @@ static int emc2305_set_single_tz(struct device *dev, int idx)
 	pwm = data->pwm_min[cdev_idx];
 
 	data->cdev_data[cdev_idx].cdev =
-		thermal_cooling_device_register(emc2305_fan_name[idx], data,
-						&emc2305_cooling_ops);
+		devm_thermal_of_cooling_device_register(dev, dev->of_node,
+							emc2305_fan_name[idx], data,
+							&emc2305_cooling_ops);
 
 	if (IS_ERR(data->cdev_data[cdev_idx].cdev)) {
 		dev_err(dev, "Failed to register cooling device %s\n", emc2305_fan_name[idx]);
@@ -332,24 +331,9 @@ static int emc2305_set_tz(struct device *dev)
 	for (i = 0; i < data->pwm_num; i++) {
 		ret = emc2305_set_single_tz(dev, i + 1);
 		if (ret)
-			goto thermal_cooling_device_register_fail;
+			return ret;
 	}
 	return 0;
-
-thermal_cooling_device_register_fail:
-	emc2305_unset_tz(dev);
-	return ret;
-}
-
-static void emc2305_unset_tz(struct device *dev)
-{
-	struct emc2305_data *data = dev_get_drvdata(dev);
-	int i;
-
-	/* Unregister cooling device. */
-	for (i = 0; i < EMC2305_PWM_MAX; i++)
-		if (data->cdev_data[i].cdev)
-			thermal_cooling_device_unregister(data->cdev_data[i].cdev);
 }
 
 static umode_t
@@ -599,14 +583,6 @@ static int emc2305_probe(struct i2c_client *client)
 	return 0;
 }
 
-static void emc2305_remove(struct i2c_client *client)
-{
-	struct device *dev = &client->dev;
-
-	if (IS_REACHABLE(CONFIG_THERMAL))
-		emc2305_unset_tz(dev);
-}
-
 static const struct of_device_id of_emc2305_match_table[] = {
 	{ .compatible = "microchip,emc2305", },
 	{},
@@ -619,7 +595,6 @@ static struct i2c_driver emc2305_driver = {
 		.of_match_table = of_emc2305_match_table,
 	},
 	.probe = emc2305_probe,
-	.remove	  = emc2305_remove,
 	.id_table = emc2305_ids,
 };
 
-- 
2.34.1

Re: [PATCH v6 1/3] dt-bindings: hwmon: Add Microchip emc2305 support

[Rob Herring]

On Fri, Mar 21, 2025 at 04:33:06PM +0200, florin.leotescu@oss.nxp.com wrote:
> From: Florin Leotescu <florin.leotescu@nxp.com>
> 
> Introduce yaml schema for Microchip emc2305 pwm fan controller.
> 
> Signed-off-by: Florin Leotescu <florin.leotescu@nxp.com>
> Reviewed-by: Frank Li <Frank.Li@nxp.com>
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> ---
>  .../bindings/hwmon/microchip,emc2305.yaml     | 110 ++++++++++++++++++
>  1 file changed, 110 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/hwmon/microchip,emc2305.yaml
> 
> diff --git a/Documentation/devicetree/bindings/hwmon/microchip,emc2305.yaml b/Documentation/devicetree/bindings/hwmon/microchip,emc2305.yaml
> new file mode 100644
> index 000000000000..79081c116274
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/microchip,emc2305.yaml
> @@ -0,0 +1,110 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/hwmon/microchip,emc2305.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Microchip EMC2305 SMBus compliant PWM fan controller
> +
> +maintainers:
> +  - Michael Shych <michaelsh@nvidia.com>
> +
> +description:
> +  Microchip EMC2301/2/3/5 pwm controller which supports
> +  up to five programmable fan control circuits.

Fix wrapping to wrap at 80.

> +
> +properties:
> +  compatible:
> +    oneOf:
> +      - enum:
> +          - microchip,emc2305
> +      - items:
> +          - enum:
> +              - microchip,emc2303
> +              - microchip,emc2302
> +              - microchip,emc2301
> +          - const: microchip,emc2305
> +
> +  reg:
> +    maxItems: 1
> +
> +  '#address-cells':
> +    const: 1
> +
> +  '#size-cells':
> +    const: 0
> +
> +  '#pwm-cells':
> +    const: 3
> +    description: |
> +      Number of cells in a PWM specifier.
> +      - cell 0: The PWM frequency
> +      - cell 1: The PWM polarity: 0 or PWM_POLARITY_INVERTED
> +      - cell 2: The PWM output config:
> +           - 0 (Open-Drain)
> +           - 1 (Push-Pull)
> +
> +patternProperties:
> +  '^fan@[0-4]$':
> +    $ref: fan-common.yaml#
> +    unevaluatedProperties: false
> +    properties:
> +      reg:
> +        description:
> +          The fan number used to determine the associated PWM channel.

           maxItems: 1

With that,

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>

Re: [PATCH v6 1/3] dt-bindings: hwmon: Add Microchip emc2305 support

[Guenter Roeck]

On Fri, Mar 21, 2025 at 04:33:06PM +0200, florin.leotescu@oss.nxp.com wrote:
> From: Florin Leotescu <florin.leotescu@nxp.com>
> 
> Introduce yaml schema for Microchip emc2305 pwm fan controller.
> 
> Signed-off-by: Florin Leotescu <florin.leotescu@nxp.com>
> Reviewed-by: Frank Li <Frank.Li@nxp.com>
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> Reviewed-by: Rob Herring (Arm) <robh@kernel.org>

Applied, after making the changes requested by Rob.

Thanks,
Guenter

Re: [PATCH v6 2/3] hwmon: emc2305: Add OF support

[Guenter Roeck]

On Fri, Mar 21, 2025 at 04:33:07PM +0200, florin.leotescu@oss.nxp.com wrote:
> From: Florin Leotescu <florin.leotescu@nxp.com>
> 
> Introduce OF support for Microchip emc2305 pwm fan controller.
> 
> Signed-off-by: Florin Leotescu <florin.leotescu@nxp.com>
> Reviewed-by: Frank Li <Frank.Li@nxp.com>

Applied.

Thanks,
Guenter

Re: [PATCH v6 3/3] hwmon: emc2305: Use devm_thermal_of_cooling_device_register

[Guenter Roeck]

On Fri, Mar 21, 2025 at 04:33:08PM +0200, florin.leotescu@oss.nxp.com wrote:
> From: Florin Leotescu <florin.leotescu@nxp.com>
> 
> Prepare the emc2305 driver to use configuration from Device Tree nodes.
> Switch to devm_thermal_of_cooling_device_register to simplify the
> cleanup procedure, allowing the removal of emc2305_unset_tz and
> emc2305_remove, which are no longer needed.
> 
> Signed-off-by: Florin Leotescu <florin.leotescu@nxp.com>
> Reviewed-by: Frank Li <Frank.Li@nxp.com>

Applied.

Thanks,
Guenter