[PATCH v8 0/4] Add devicetree support for max6639

[PATCH v8 0/4] Add devicetree support for max6639

[Naresh Solanki]

These patches adds devicetree support for MAX6639.

Changes in V8:
- remove items for reg property
- Fix indentation example
- Set pwms property type to object
- Update pwms property description
- Update title
- Remove unrelated changes
Changes in V7:
- Split the patch into
 1. add dt support for max6639
 2. Add pwm support
- Ad DT property min-rpm in fan-common.yaml
Changes in V6:
- Remove unused header file
- minor cleanup 
Changes in V5:
- Add pwms support
Changes V4:
- Fix dt error
- update comment
Changes V3:
- correct fan dt property name
- remove unrelevent changes
Changes V2:
- Fix dt schema error.
Changes:
- Add fan-common dt schema.
- add dt-binding support for max6639
- add max6639 specific property

Marcello Sylvester Bauer (2):
  dt-bindings: hwmon: Add max6639
  hwmon: (max6639) Change from pdata to dt configuration

Naresh Solanki (2):
  dt-bindings: hwmon: fan: Add Common Fan Properties
  hwmon: (max6639) Add pwm support

 .../devicetree/bindings/hwmon/fan-common.yaml |  48 +++
 .../bindings/hwmon/maxim,max6639.yaml         |  92 +++++
 drivers/hwmon/Kconfig                         |   1 +
 drivers/hwmon/max6639.c                       | 363 +++++++++++++++---
 include/linux/platform_data/max6639.h         |  15 -
 5 files changed, 459 insertions(+), 60 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/hwmon/fan-common.yaml
 create mode 100644 Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml
 delete mode 100644 include/linux/platform_data/max6639.h


base-commit: 10b7c400596e0010ce12b373ac7b18b7eb334e92
-- 
2.37.3

[PATCH v8 1/4] dt-bindings: hwmon: fan: Add Common Fan Properties

[Naresh Solanki]

Add common fan properties bindings to a schema.

Bindings for fan controllers can reference the common schema for the
fan

child nodes:

  patternProperties:
    "^fan@[0-2]":
      type: object
      $ref: fan-common.yaml#

Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
---
 .../devicetree/bindings/hwmon/fan-common.yaml | 48 +++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwmon/fan-common.yaml

diff --git a/Documentation/devicetree/bindings/hwmon/fan-common.yaml b/Documentation/devicetree/bindings/hwmon/fan-common.yaml
new file mode 100644
index 000000000000..330fb1552821
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/fan-common.yaml
@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: GPL-2.0-or-later OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwmon/fan-common.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Common Fan Properties
+
+maintainers:
+  - Naresh Solanki <naresh.solanki@9elements.com>
+
+properties:
+  max-rpm:
+    description:
+      Max RPM supported by fan.
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  min-rpm:
+    description:
+      Min RPM supported by fan.
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  pulses-per-revolution:
+    description:
+      The number of pulse from fan sensor per revolution.
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  target-rpm:
+    description:
+      Target RPM the fan should be configured during driver probe.
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+  pwms:
+    maxItems: 1
+    description:
+      PWM signal for the fan
+
+  label:
+    description:
+      Optional fan label
+
+  fan-supply:
+    description:
+      Power supply for fan.
+
+additionalProperties: true
+
+...
-- 
2.37.3

[PATCH v8 2/4] dt-bindings: hwmon: Add max6639

[Naresh Solanki]

From: Marcello Sylvester Bauer <sylv@sylv.io>

Add Devicetree binding documentation for Maxim MAX6639 temperature
monitor with PWM fan-speed controller.

Signed-off-by: Marcello Sylvester Bauer <sylv@sylv.io>
Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
---
 .../bindings/hwmon/maxim,max6639.yaml         | 92 +++++++++++++++++++
 1 file changed, 92 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml

diff --git a/Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml b/Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml
new file mode 100644
index 000000000000..78a09ce35986
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml
@@ -0,0 +1,92 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+
+$id: http://devicetree.org/schemas/hwmon/maxim,max6639.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Maxim max6639
+
+maintainers:
+  - Roland Stigge <stigge@antcom.de>
+
+description: |
+  The MAX6639 is a 2-channel temperature monitor with dual, automatic, PWM
+  fan-speed controller.  It monitors its own temperature and one external
+  diode-connected transistor or the temperatures of two external diode-connected
+  transistors, typically available in CPUs, FPGAs, or GPUs.
+
+  Datasheets:
+    https://datasheets.maximintegrated.com/en/ds/MAX6639-MAX6639F.pdf
+
+properties:
+  compatible:
+    enum:
+      - maxim,max6639
+
+  reg:
+    maxItems: 1
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+  '#pwm-cells':
+    const: 3
+
+required:
+  - compatible
+  - reg
+
+patternProperties:
+  "^fan@[0-1]$":
+    type: object
+    description: |
+      Represents the two fans and their specific configuration.
+
+    $ref: fan-common.yaml#
+
+    unevaluatedProperties: false
+
+    properties:
+      reg:
+        description: |
+          The fan number.
+
+    required:
+      - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        fan1: fan-controller@10 {
+            compatible = "maxim,max6639";
+            reg = <0x10>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+            #pwm-cells = <3>;
+
+            fan@0 {
+                reg = <0x0>;
+                pulses-per-revolution = <2>;
+                max-rpm = <4000>;
+                target-rpm = <1000>;
+                pwms = <&fan1 0 25000 0>;
+            };
+
+            fan@1 {
+                reg = <0x1>;
+                pulses-per-revolution = <2>;
+                max-rpm = <8000>;
+                pwms = <&fan1 1 25000 0>;
+            };
+        };
+    };
+...
-- 
2.37.3

[PATCH v8 3/4] hwmon: (max6639) Change from pdata to dt configuration

[Naresh Solanki]

From: Marcello Sylvester Bauer <sylv@sylv.io>

max6639_platform_data is not used by any in-kernel driver and does not
address the MAX6639 fans separately.
Move to device tree configuration with explicit properties to configure
each fan.

Signed-off-by: Marcello Sylvester Bauer <sylv@sylv.io>
Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
---
 drivers/hwmon/max6639.c               | 122 +++++++++++++++++++-------
 include/linux/platform_data/max6639.h |  15 ----
 2 files changed, 90 insertions(+), 47 deletions(-)
 delete mode 100644 include/linux/platform_data/max6639.h

diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c
index 9b895402c80d..e09358713bef 100644
--- a/drivers/hwmon/max6639.c
+++ b/drivers/hwmon/max6639.c
@@ -19,7 +19,6 @@
 #include <linux/hwmon-sysfs.h>
 #include <linux/err.h>
 #include <linux/mutex.h>
-#include <linux/platform_data/max6639.h>
 
 /* Addresses to scan */
 static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
@@ -85,8 +84,8 @@ struct max6639_data {
 	u8 temp_ot[2];		/* OT Temperature, 0..255 C (->_emergency) */
 
 	/* Register values initialized only once */
-	u8 ppr;			/* Pulses per rotation 0..3 for 1..4 ppr */
-	u8 rpm_range;		/* Index in above rpm_ranges table */
+	u8 ppr[2];		/* Pulses per rotation 0..3 for 1..4 ppr */
+	u8 rpm_range[2];	/* Index in above rpm_ranges table */
 
 	/* Optional regulator for FAN supply */
 	struct regulator *reg;
@@ -319,7 +318,7 @@ static ssize_t fan_input_show(struct device *dev,
 		return PTR_ERR(data);
 
 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index],
-		       data->rpm_range));
+		       data->rpm_range[attr->index]));
 }
 
 static ssize_t alarm_show(struct device *dev,
@@ -404,11 +403,7 @@ static int rpm_range_to_reg(int range)
 static int max6639_init_client(struct i2c_client *client,
 			       struct max6639_data *data)
 {
-	struct max6639_platform_data *max6639_info =
-		dev_get_platdata(&client->dev);
-	int i;
-	int rpm_range = 1; /* default: 4000 RPM */
-	int err;
+	int i, err;
 
 	/* Reset chip to default values, see below for GCONFIG setup */
 	err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
@@ -416,43 +411,22 @@ static int max6639_init_client(struct i2c_client *client,
 	if (err)
 		goto exit;
 
-	/* Fans pulse per revolution is 2 by default */
-	if (max6639_info && max6639_info->ppr > 0 &&
-			max6639_info->ppr < 5)
-		data->ppr = max6639_info->ppr;
-	else
-		data->ppr = 2;
-	data->ppr -= 1;
-
-	if (max6639_info)
-		rpm_range = rpm_range_to_reg(max6639_info->rpm_range);
-	data->rpm_range = rpm_range;
-
 	for (i = 0; i < 2; i++) {
 
 		/* Set Fan pulse per revolution */
 		err = i2c_smbus_write_byte_data(client,
 				MAX6639_REG_FAN_PPR(i),
-				data->ppr << 6);
+				data->ppr[i] << 6);
 		if (err)
 			goto exit;
 
 		/* Fans config PWM, RPM */
 		err = i2c_smbus_write_byte_data(client,
 			MAX6639_REG_FAN_CONFIG1(i),
-			MAX6639_FAN_CONFIG1_PWM | rpm_range);
+			MAX6639_FAN_CONFIG1_PWM | data->rpm_range[i]);
 		if (err)
 			goto exit;
 
-		/* Fans PWM polarity high by default */
-		if (max6639_info && max6639_info->pwm_polarity == 0)
-			err = i2c_smbus_write_byte_data(client,
-				MAX6639_REG_FAN_CONFIG2a(i), 0x00);
-		else
-			err = i2c_smbus_write_byte_data(client,
-				MAX6639_REG_FAN_CONFIG2a(i), 0x02);
-		if (err)
-			goto exit;
 
 		/*
 		 * /THERM full speed enable,
@@ -524,6 +498,76 @@ static void max6639_regulator_disable(void *data)
 	regulator_disable(data);
 }
 
+static int max6639_probe_child_from_dt(struct i2c_client *client,
+				      struct device_node *child,
+				      struct max6639_data *data)
+
+{
+	struct device *dev = &client->dev;
+	u32 i, maxrpm;
+	int val, err;
+
+	err = of_property_read_u32(child, "reg", &i);
+	if (err) {
+		dev_err(dev, "missing reg property of %pOFn\n", child);
+		return err;
+	}
+
+	if (i >= 2) {
+		dev_err(dev, "invalid reg %d of %pOFn\n", i, child);
+		return -EINVAL;
+	}
+
+	err = of_property_read_u32(child, "pulses-per-revolution", &val);
+	if (err) {
+		dev_err(dev, "missing pulses-per-revolution property of %pOFn",
+			child);
+		return err;
+	}
+
+	if (val < 0 || val > 5) {
+		dev_err(dev, "invalid pulses-per-revolution %d of %pOFn\n", val,
+			child);
+		return -EINVAL;
+	}
+	data->ppr[i] = val;
+
+	err = of_property_read_u32(child, "max-rpm", &maxrpm);
+	if (err) {
+		dev_err(dev, "missing max-rpm property of %pOFn\n", child);
+		return err;
+	}
+
+	data->rpm_range[i] = rpm_range_to_reg(maxrpm);
+
+	return 0;
+}
+static int max6639_probe_from_dt(struct i2c_client *client,
+				struct max6639_data *data)
+{
+	struct device *dev = &client->dev;
+	const struct device_node *np = dev->of_node;
+	struct device_node *child;
+	int err;
+
+	/* Compatible with non-DT platforms */
+	if (!np)
+		return 0;
+
+	for_each_child_of_node(np, child) {
+		if (strcmp(child->name, "fan"))
+			continue;
+
+		err = max6639_probe_child_from_dt(client, child, data);
+		if (err) {
+			of_node_put(child);
+			return err;
+		}
+	}
+
+	return 0;
+}
+
 static int max6639_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
@@ -560,6 +604,11 @@ static int max6639_probe(struct i2c_client *client)
 
 	mutex_init(&data->update_lock);
 
+	/* Probe from DT to get configuration */
+	err = max6639_probe_from_dt(client, data);
+	if (err)
+		return err;
+
 	/* Initialize the max6639 chip */
 	err = max6639_init_client(client, data);
 	if (err < 0)
@@ -616,6 +665,14 @@ static const struct i2c_device_id max6639_id[] = {
 
 MODULE_DEVICE_TABLE(i2c, max6639_id);
 
+#ifdef CONFIG_OF
+static const struct of_device_id maxim_of_platform_match[] = {
+	{.compatible = "maxim,max6639"},
+	{},
+};
+MODULE_DEVICE_TABLE(of, maxim_of_platform_match);
+#endif
+
 static DEFINE_SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume);
 
 static struct i2c_driver max6639_driver = {
@@ -623,6 +680,7 @@ static struct i2c_driver max6639_driver = {
 	.driver = {
 		   .name = "max6639",
 		   .pm = pm_sleep_ptr(&max6639_pm_ops),
+		   .of_match_table = of_match_ptr(maxim_of_platform_match),
 		   },
 	.probe_new = max6639_probe,
 	.id_table = max6639_id,
diff --git a/include/linux/platform_data/max6639.h b/include/linux/platform_data/max6639.h
deleted file mode 100644
index 65bfdb4fdc15..000000000000
--- a/include/linux/platform_data/max6639.h
+++ /dev/null
@@ -1,15 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _LINUX_MAX6639_H
-#define _LINUX_MAX6639_H
-
-#include <linux/types.h>
-
-/* platform data for the MAX6639 temperature sensor and fan control */
-
-struct max6639_platform_data {
-	bool pwm_polarity;	/* Polarity low (0) or high (1, default) */
-	int ppr;		/* Pulses per rotation 1..4 (default == 2) */
-	int rpm_range;		/* 2000, 4000 (default), 8000 or 16000 */
-};
-
-#endif /* _LINUX_MAX6639_H */
-- 
2.37.3

[PATCH v8 4/4] hwmon: (max6639) Add pwm support

[Naresh Solanki]

Add pwm support for max6639. Also configure pwm fan speed based on pwm
provided in DT.

Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
---
 drivers/hwmon/Kconfig   |   1 +
 drivers/hwmon/max6639.c | 243 +++++++++++++++++++++++++++++++++++++---
 2 files changed, 230 insertions(+), 14 deletions(-)

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 3176c33af6c6..56d9004b7a38 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1115,6 +1115,7 @@ config SENSORS_MAX6621
 config SENSORS_MAX6639
 	tristate "Maxim MAX6639 sensor chip"
 	depends on I2C
+	depends on PWM
 	help
 	  If you say yes here you get support for the MAX6639
 	  sensor chips.
diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c
index e09358713bef..302186532e0f 100644
--- a/drivers/hwmon/max6639.c
+++ b/drivers/hwmon/max6639.c
@@ -19,6 +19,7 @@
 #include <linux/hwmon-sysfs.h>
 #include <linux/err.h>
 #include <linux/mutex.h>
+#include <linux/pwm.h>
 
 /* Addresses to scan */
 static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
@@ -53,11 +54,17 @@ static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
 #define MAX6639_GCONFIG_PWM_FREQ_HI		0x08
 
 #define MAX6639_FAN_CONFIG1_PWM			0x80
-
+#define MAX6639_REG_FAN_CONFIG2a_PWM_POL	0x02
 #define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED	0x40
+#define MAX6639_FAN_CONFIG3_FREQ_MASK		0x03
+#define MAX6639_REG_TARGTDUTY_SLOT		120
 
 static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 };
 
+/* Supported PWM frequency */
+static const unsigned int freq_table[] = { 20, 33, 50, 100, 5000, 8333, 12500,
+					   25000 };
+
 #define FAN_FROM_REG(val, rpm_range)	((val) == 0 || (val) == 255 ? \
 				0 : (rpm_ranges[rpm_range] * 30) / (val))
 #define TEMP_LIMIT_TO_REG(val)	clamp_val((val) / 1000, 0, 255)
@@ -75,6 +82,9 @@ struct max6639_data {
 	u16 temp[2];		/* Temperature, in 1/8 C, 0..255 C */
 	bool temp_fault[2];	/* Detected temperature diode failure */
 	u8 fan[2];		/* Register value: TACH count for fans >=30 */
+	struct pwm_device *pwmd[2]; /* max6639 has two pwm device */
+	u32 target_rpm[2];
+	u32 max_rpm[2];
 	u8 status;		/* Detected channel alarms and fan failures */
 
 	/* Register values only written to */
@@ -89,6 +99,8 @@ struct max6639_data {
 
 	/* Optional regulator for FAN supply */
 	struct regulator *reg;
+	/* max6639 pwm chip */
+	struct pwm_chip chip;
 };
 
 static struct max6639_data *max6639_update_device(struct device *dev)
@@ -279,8 +291,11 @@ static ssize_t pwm_show(struct device *dev, struct device_attribute *dev_attr,
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
 	struct max6639_data *data = dev_get_drvdata(dev);
+	struct pwm_state state;
+
+	pwm_get_state(data->pwmd[attr->index], &state);
 
-	return sprintf(buf, "%d\n", data->pwm[attr->index] * 255 / 120);
+	return sprintf(buf, "%d\n", pwm_get_relative_duty_cycle(&state, 255));
 }
 
 static ssize_t pwm_store(struct device *dev,
@@ -289,9 +304,9 @@ static ssize_t pwm_store(struct device *dev,
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
 	struct max6639_data *data = dev_get_drvdata(dev);
-	struct i2c_client *client = data->client;
 	unsigned long val;
 	int res;
+	struct pwm_state state;
 
 	res = kstrtoul(buf, 10, &val);
 	if (res)
@@ -299,12 +314,12 @@ static ssize_t pwm_store(struct device *dev,
 
 	val = clamp_val(val, 0, 255);
 
-	mutex_lock(&data->update_lock);
-	data->pwm[attr->index] = (u8)(val * 120 / 255);
-	i2c_smbus_write_byte_data(client,
-				  MAX6639_REG_TARGTDUTY(attr->index),
-				  data->pwm[attr->index]);
-	mutex_unlock(&data->update_lock);
+	pwm_get_state(data->pwmd[attr->index], &state);
+	pwm_set_relative_duty_cycle(&state, val, 255);
+	res = pwm_apply_state(data->pwmd[attr->index], &state);
+	if (res)
+		return res;
+
 	return count;
 }
 
@@ -404,6 +419,7 @@ static int max6639_init_client(struct i2c_client *client,
 			       struct max6639_data *data)
 {
 	int i, err;
+	struct pwm_state state;
 
 	/* Reset chip to default values, see below for GCONFIG setup */
 	err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
@@ -457,10 +473,11 @@ static int max6639_init_client(struct i2c_client *client,
 		if (err)
 			goto exit;
 
-		/* PWM 120/120 (i.e. 100%) */
-		data->pwm[i] = 120;
-		err = i2c_smbus_write_byte_data(client,
-				MAX6639_REG_TARGTDUTY(i), data->pwm[i]);
+		/* Configure PWM controller */
+		pwm_get_state(data->pwmd[i], &state);
+		pwm_set_relative_duty_cycle(&state, data->target_rpm[i],
+					   data->max_rpm[i]);
+		err = pwm_apply_state(data->pwmd[i], &state);
 		if (err)
 			goto exit;
 	}
@@ -539,8 +556,31 @@ static int max6639_probe_child_from_dt(struct i2c_client *client,
 	}
 
 	data->rpm_range[i] = rpm_range_to_reg(maxrpm);
+	data->max_rpm[i] = maxrpm;
 
-	return 0;
+	err = of_property_read_u32(child, "target-rpm", &val);
+	/* Use provided target RPM else default to maxrpm */
+	if (!err)
+		data->target_rpm[i] = val;
+	else
+		data->target_rpm[i] = maxrpm;
+
+	/* Get pwms property for PWM control */
+	data->pwmd[i] = devm_fwnode_pwm_get(dev, &child->fwnode, NULL);
+
+	if (!IS_ERR(data->pwmd[i]))
+		return 0;
+
+	if (PTR_ERR(data->pwmd[i]) == -EPROBE_DEFER)
+		return PTR_ERR(data->pwmd[i]);
+
+	dev_dbg(dev, "Using chip default PWM");
+	data->pwmd[i] = pwm_request_from_chip(&data->chip, i, NULL);
+	if (!IS_ERR(data->pwmd[i]))
+		return 0;
+
+	dev_dbg(dev, "Failed to configure pwm for fan %d", i);
+	return PTR_ERR_OR_ZERO(data->pwmd[i]);
 }
 static int max6639_probe_from_dt(struct i2c_client *client,
 				struct max6639_data *data)
@@ -568,6 +608,172 @@ static int max6639_probe_from_dt(struct i2c_client *client,
 	return 0;
 }
 
+static struct max6639_data *to_max6639_pwm(struct pwm_chip *chip)
+{
+	return container_of(chip, struct max6639_data, chip);
+}
+
+static void max6639_pwm_get_state(struct pwm_chip *chip,
+				  struct pwm_device *pwm,
+				  struct pwm_state *state)
+{
+
+	struct max6639_data *data = to_max6639_pwm(chip);
+	struct i2c_client *client = data->client;
+	int value, i = pwm->hwpwm, x;
+	unsigned int freq;
+
+	mutex_lock(&data->update_lock);
+
+	value = i2c_smbus_read_byte_data(client, MAX6639_REG_FAN_CONFIG1(i));
+	if (value < 0)
+		goto abort;
+
+	if (value & MAX6639_FAN_CONFIG1_PWM) {
+		state->enabled = true;
+
+		/* Determine frequency from respective registers */
+		value = i2c_smbus_read_byte_data(client,
+						 MAX6639_REG_FAN_CONFIG3(i));
+		if (value < 0)
+			goto abort;
+		x = value & MAX6639_FAN_CONFIG3_FREQ_MASK;
+
+		value = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
+		if (value < 0)
+			goto abort;
+		if (value & MAX6639_GCONFIG_PWM_FREQ_HI)
+			x |= 0x4;
+		x &= 0x7;
+		freq = freq_table[x];
+
+		state->period = DIV_ROUND_UP(NSEC_PER_SEC, freq);
+
+		value = i2c_smbus_read_byte_data(client,
+						 MAX6639_REG_TARGTDUTY(i));
+		if (value < 0)
+			goto abort;
+		/* max6639 supports 120 slots only */
+		state->duty_cycle = mul_u64_u32_div(state->period, value, 120);
+
+		value = i2c_smbus_read_byte_data(client,
+						 MAX6639_REG_FAN_CONFIG2a(i));
+		if (value < 0)
+			goto abort;
+		value &= MAX6639_REG_FAN_CONFIG2a_PWM_POL;
+		state->polarity = (value != 0);
+	} else
+		state->enabled = false;
+
+abort:
+	mutex_unlock(&data->update_lock);
+
+}
+
+static int max6639_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+			     const struct pwm_state *state)
+{
+	struct max6639_data *data = to_max6639_pwm(chip);
+	struct i2c_client *client = data->client;
+	int value = 0, i = pwm->hwpwm, x;
+	unsigned int freq;
+	struct pwm_state cstate;
+
+	cstate = pwm->state;
+
+	mutex_lock(&data->update_lock);
+
+	if (state->period != cstate.period) {
+		/* Configure frequency */
+		freq = DIV_ROUND_UP_ULL(NSEC_PER_SEC, state->period);
+		/* Chip supports limited number of frequency */
+		for (x = 0; x < sizeof(freq_table); x++)
+			if (freq <= freq_table[x])
+				break;
+
+		value = i2c_smbus_read_byte_data(client,
+						 MAX6639_REG_FAN_CONFIG3(i));
+		if (value < 0)
+			goto abort;
+		value &= ~MAX6639_FAN_CONFIG3_FREQ_MASK;
+		value |= (x & MAX6639_FAN_CONFIG3_FREQ_MASK);
+		value = i2c_smbus_write_byte_data(client,
+						  MAX6639_REG_FAN_CONFIG3(i),
+						  value);
+
+		value = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG);
+		if (value < 0)
+			goto abort;
+
+		if (x >> 2)
+			value &= ~MAX6639_GCONFIG_PWM_FREQ_HI;
+		else
+			value |= MAX6639_GCONFIG_PWM_FREQ_HI;
+		value = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
+						  value);
+		if (value < 0)
+			goto abort;
+	}
+
+	/* Configure dutycycle */
+	if (state->duty_cycle != cstate.duty_cycle ||
+	    state->period != cstate.period) {
+		value = DIV_ROUND_DOWN_ULL(
+				state->duty_cycle * MAX6639_REG_TARGTDUTY_SLOT,
+				state->period);
+		value = i2c_smbus_write_byte_data(client,
+						  MAX6639_REG_TARGTDUTY(i),
+						  value);
+		if (value < 0)
+			goto abort;
+	}
+
+	/* Configure polarity */
+	if (state->polarity != cstate.polarity) {
+		value = i2c_smbus_read_byte_data(client,
+						 MAX6639_REG_FAN_CONFIG2a(i));
+		if (value < 0)
+			goto abort;
+		if (state->polarity == PWM_POLARITY_NORMAL)
+			value |= MAX6639_REG_FAN_CONFIG2a_PWM_POL;
+		else
+			value &= ~MAX6639_REG_FAN_CONFIG2a_PWM_POL;
+		value = i2c_smbus_write_byte_data(client,
+						  MAX6639_REG_FAN_CONFIG2a(i),
+						  value);
+		if (value < 0)
+			goto abort;
+	}
+
+	if (state->enabled == cstate.enabled)
+		goto abort;
+
+	value = i2c_smbus_read_byte_data(client, MAX6639_REG_FAN_CONFIG1(i));
+	if (value < 0)
+		goto abort;
+	if (state->enabled)
+		value |= MAX6639_FAN_CONFIG1_PWM;
+	else
+		value &= ~MAX6639_FAN_CONFIG1_PWM;
+
+	value = i2c_smbus_write_byte_data(client, MAX6639_REG_FAN_CONFIG1(i),
+					  value);
+	if (value < 0)
+		goto abort;
+	value = 0;
+
+abort:
+	mutex_unlock(&data->update_lock);
+
+	return value;
+}
+
+static const struct pwm_ops max6639_pwm_ops = {
+	.apply = max6639_pwm_apply,
+	.get_state = max6639_pwm_get_state,
+	.owner = THIS_MODULE,
+};
+
 static int max6639_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
@@ -581,6 +787,15 @@ static int max6639_probe(struct i2c_client *client)
 
 	data->client = client;
 
+	/* Add PWM controller of max6639 */
+	data->chip.dev = dev;
+	data->chip.ops = &max6639_pwm_ops;
+	data->chip.npwm = 2;
+
+	err = devm_pwmchip_add(dev, &data->chip);
+	if (err < 0)
+		return dev_err_probe(dev, err, "failed to add PWM chip\n");
+
 	data->reg = devm_regulator_get_optional(dev, "fan");
 	if (IS_ERR(data->reg)) {
 		if (PTR_ERR(data->reg) != -ENODEV)
-- 
2.37.3

Re: [PATCH v8 4/4] hwmon: (max6639) Add pwm support

[Uwe Kleine-König]

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On Tue, Nov 29, 2022 at 05:11:34PM +0100, Naresh Solanki wrote:
> Add pwm support for max6639. Also configure pwm fan speed based on pwm
> provided in DT.

Did you do anything to resolve the questions I had in reply to v5? If
yes, I must have missed it.

Note that maintainer time is scarce and with sending new versions of a
patch with no sign that you improved in the aspects that were critized
before, you're burning that scarce time and loosing the good will of the
responsible maintainers.

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | https://www.pengutronix.de/ |

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Re: [PATCH v8 4/4] hwmon: (max6639) Add pwm support

[Guenter Roeck]

On 11/29/22 08:34, Uwe Kleine-König wrote:
> On Tue, Nov 29, 2022 at 05:11:34PM +0100, Naresh Solanki wrote:
>> Add pwm support for max6639. Also configure pwm fan speed based on pwm
>> provided in DT.
> 
> Did you do anything to resolve the questions I had in reply to v5? If
> yes, I must have missed it.
> 

I don't see a response to my concerns either, especially regarding fan mode
(dc vs. pwm) in the bindings. For that reason, I won't even look at the series.

Guenter

> Note that maintainer time is scarce and with sending new versions of a
> patch with no sign that you improved in the aspects that were critized
> before, you're burning that scarce time and loosing the good will of the
> responsible maintainers.
> 
> Best regards
> Uwe
> 

Re: [PATCH v8 4/4] hwmon: (max6639) Add pwm support

[Naresh Solanki]

Hi

On 29-11-2022 10:11 pm, Guenter Roeck wrote:
> On 11/29/22 08:34, Uwe Kleine-König wrote:
>> On Tue, Nov 29, 2022 at 05:11:34PM +0100, Naresh Solanki wrote:
>>> Add pwm support for max6639. Also configure pwm fan speed based on pwm
>>> provided in DT.
>>
>> Did you do anything to resolve the questions I had in reply to v5? If
>> yes, I must have missed it.
I did split the patch to separate dt changes & pwm specific changes.
>>
> 
> I don't see a response to my concerns either, especially regarding fan mode
> (dc vs. pwm) in the bindings. For that reason, I won't even look at the 
> series.

I intend to use max6639 driver but with DT support.
Did additional changes(like using PWM provider) based on feedback I 
received.

> 
> Guenter
> 
>> Note that maintainer time is scarce and with sending new versions of a
>> patch with no sign that you improved in the aspects that were critized
>> before, you're burning that scarce time and loosing the good will of the
>> responsible maintainers.
>>
>> Best regards
>> Uwe
>>
> 
Regards,
Naresh

Re: [PATCH v8 1/4] dt-bindings: hwmon: fan: Add Common Fan Properties

[Guenter Roeck]

On Tue, Nov 29, 2022 at 05:11:31PM +0100, Naresh Solanki wrote:
> Add common fan properties bindings to a schema.
> 
> Bindings for fan controllers can reference the common schema for the
> fan
> 
> child nodes:
> 
>   patternProperties:
>     "^fan@[0-2]":
>       type: object
>       $ref: fan-common.yaml#
> 
> Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
> ---
>  .../devicetree/bindings/hwmon/fan-common.yaml | 48 +++++++++++++++++++
>  1 file changed, 48 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/hwmon/fan-common.yaml
> 
> diff --git a/Documentation/devicetree/bindings/hwmon/fan-common.yaml b/Documentation/devicetree/bindings/hwmon/fan-common.yaml
> new file mode 100644
> index 000000000000..330fb1552821
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/fan-common.yaml
> @@ -0,0 +1,48 @@
> +# SPDX-License-Identifier: GPL-2.0-or-later OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/hwmon/fan-common.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Common Fan Properties
> +
> +maintainers:
> +  - Naresh Solanki <naresh.solanki@9elements.com>
> +
> +properties:
> +  max-rpm:
> +    description:
> +      Max RPM supported by fan.
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +
> +  min-rpm:
> +    description:
> +      Min RPM supported by fan.
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +
> +  pulses-per-revolution:
> +    description:
> +      The number of pulse from fan sensor per revolution.
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +
> +  target-rpm:
> +    description:
> +      Target RPM the fan should be configured during driver probe.
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +
> +  pwms:
> +    maxItems: 1
> +    description:
> +      PWM signal for the fan
> +
> +  label:
> +    description:
> +      Optional fan label
> +
> +  fan-supply:
> +    description:
> +      Power supply for fan.
> +

I still don't see fan mode (DC or PWM). I understand that you don't care,
but from my perspective it must be addressed in generic fan properties,
especially to ensure agreement on how 'pwms' is handled on a system where
the fan mode is configurable, and how to select the fan speed on systems
supporting DC fans.

Guenter

Re: [PATCH v8 4/4] hwmon: (max6639) Add pwm support

[Naresh Solanki]

Hi Guenter, Rob

On 29-11-2022 10:11 pm, Guenter Roeck wrote:
> On 11/29/22 08:34, Uwe Kleine-König wrote:
>> On Tue, Nov 29, 2022 at 05:11:34PM +0100, Naresh Solanki wrote:
>>> Add pwm support for max6639. Also configure pwm fan speed based on pwm
>>> provided in DT.
>>
>> Did you do anything to resolve the questions I had in reply to v5? If
>> yes, I must have missed it.
>>
> 
> I don't see a response to my concerns either, especially regarding fan mode
> (dc vs. pwm) in the bindings. For that reason, I won't even look at the 
> series.
Best I can think of regulator with voltage control. Because as per my 
understanding, DC control fan essentially control DC voltage on negative 
pin of fan.


Regards,
Naresh
> 
> Guenter
> 
>> Note that maintainer time is scarce and with sending new versions of a
>> patch with no sign that you improved in the aspects that were critized
>> before, you're burning that scarce time and loosing the good will of the
>> responsible maintainers.
>>
>> Best regards
>> Uwe
>>
> 

Re: [PATCH v8 4/4] hwmon: (max6639) Add pwm support

[Naresh Solanki]

Hi Rob, Guenter,

I need your inputs & direction on the next step for max6639 driver.
I'm willing to work & implement changes.

Thank you for your time and consideration.

Regards,
Naresh Solanki

Regards,
Naresh Solanki



9elements GmbH, Kortumstraße 19-21, 44787 Bochum, Germany
Email:  naresh.solanki@9elements.com
Mobile:  +91 9538631477

Sitz der Gesellschaft: Bochum
Handelsregister: Amtsgericht Bochum, HRB 17519
Geschäftsführung: Sebastian Deutsch, Eray Basar

Datenschutzhinweise nach Art. 13 DSGVO


On Tue, 6 Dec 2022 at 23:15, Naresh Solanki
<naresh.solanki@9elements.com> wrote:
>
> Hi Guenter, Rob
>
> On 29-11-2022 10:11 pm, Guenter Roeck wrote:
> > On 11/29/22 08:34, Uwe Kleine-König wrote:
> >> On Tue, Nov 29, 2022 at 05:11:34PM +0100, Naresh Solanki wrote:
> >>> Add pwm support for max6639. Also configure pwm fan speed based on pwm
> >>> provided in DT.
> >>
> >> Did you do anything to resolve the questions I had in reply to v5? If
> >> yes, I must have missed it.
> >>
> >
> > I don't see a response to my concerns either, especially regarding fan mode
> > (dc vs. pwm) in the bindings. For that reason, I won't even look at the
> > series.
> Best I can think of regulator with voltage control. Because as per my
> understanding, DC control fan essentially control DC voltage on negative
> pin of fan.
>
>
> Regards,
> Naresh
> >
> > Guenter
> >
> >> Note that maintainer time is scarce and with sending new versions of a
> >> patch with no sign that you improved in the aspects that were critized
> >> before, you're burning that scarce time and loosing the good will of the
> >> responsible maintainers.
> >>
> >> Best regards
> >> Uwe
> >>
> >