* [PATCH v5 0/3] Add devicetree support for max6639
@ 2022-11-15 12:20 Naresh Solanki
2022-11-15 12:20 ` [PATCH v5 1/3] dt-bindings: hwmon: fan: Add fan binding to schema Naresh Solanki
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Naresh Solanki @ 2022-11-15 12:20 UTC (permalink / raw)
To: devicetree, Guenter Roeck, Jean Delvare
Cc: linux-kernel, linux-hwmon, Patrick Rudolph, Naresh Solanki
These patches adds devicetree support for MAX6639.
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 (1):
dt-bindings: hwmon: Add binding for max6639
Naresh Solanki (2):
dt-bindings: hwmon: fan: Add fan binding to schema
hwmon: (max6639) Change from pdata to dt configuration
.../devicetree/bindings/hwmon/fan-common.yaml | 42 ++
.../bindings/hwmon/maxim,max6639.yaml | 93 ++++
drivers/hwmon/Kconfig | 1 +
drivers/hwmon/max6639.c | 465 +++++++++++++++---
4 files changed, 527 insertions(+), 74 deletions(-)
create mode 100644 Documentation/devicetree/bindings/hwmon/fan-common.yaml
create mode 100644 Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml
base-commit: 0cf46a653bdae56683fece68dc50340f7520e6c4
--
2.37.3
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v5 1/3] dt-bindings: hwmon: fan: Add fan binding to schema
2022-11-15 12:20 [PATCH v5 0/3] Add devicetree support for max6639 Naresh Solanki
@ 2022-11-15 12:20 ` Naresh Solanki
2022-11-15 12:20 ` [PATCH v5 2/3] dt-bindings: hwmon: Add binding for max6639 Naresh Solanki
2022-11-15 12:20 ` [PATCH v5 3/3] hwmon: (max6639) Change from pdata to dt configuration Naresh Solanki
2 siblings, 0 replies; 6+ messages in thread
From: Naresh Solanki @ 2022-11-15 12:20 UTC (permalink / raw)
To: devicetree, Guenter Roeck, Jean Delvare, Rob Herring,
Krzysztof Kozlowski, Naresh Solanki
Cc: linux-kernel, linux-hwmon, Patrick Rudolph, 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
$ref: fan-common.yaml#
Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
---
.../devicetree/bindings/hwmon/fan-common.yaml | 42 +++++++++++++++++++
1 file changed, 42 insertions(+)
create mode 100644 Documentation/devicetree/bindings/hwmon/fan-common.yaml
diff --git a/Documentation/devicetree/bindings/hwmon/fan-common.yaml b/Documentation/devicetree/bindings/hwmon/fan-common.yaml
new file mode 100644
index 000000000000..1954882eed77
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/fan-common.yaml
@@ -0,0 +1,42 @@
+# SPDX-License-Identifier: GPL-2.0-or-later OR BSD-2-Clause
+%YAML 1.2
+---
+$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
+
+ 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.
+ $ref: /schemas/types.yaml#/definitions/uint32
+
+ pwms:
+ description:
+ PWM provider.
+
+ label:
+ description:
+ Optional fan label
+
+ fan-supply:
+ description:
+ Power supply for fan.
+
+additionalProperties: true
+
+...
--
2.37.3
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v5 2/3] dt-bindings: hwmon: Add binding for max6639
2022-11-15 12:20 [PATCH v5 0/3] Add devicetree support for max6639 Naresh Solanki
2022-11-15 12:20 ` [PATCH v5 1/3] dt-bindings: hwmon: fan: Add fan binding to schema Naresh Solanki
@ 2022-11-15 12:20 ` Naresh Solanki
2022-11-15 12:20 ` [PATCH v5 3/3] hwmon: (max6639) Change from pdata to dt configuration Naresh Solanki
2 siblings, 0 replies; 6+ messages in thread
From: Naresh Solanki @ 2022-11-15 12:20 UTC (permalink / raw)
To: devicetree, Guenter Roeck, Jean Delvare, Rob Herring,
Krzysztof Kozlowski, Roland Stigge
Cc: linux-kernel, linux-hwmon, Patrick Rudolph,
Marcello Sylvester Bauer, Naresh Solanki
From: Marcello Sylvester Bauer <sylv@sylv.io>
Add Devicetree binding documentation for Maxim MAX6639 temperature
monitor with PWM fan-speed controller.
Signed-off-by: Marcello Sylvester Bauer <sylv@sylv.io>
Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
---
.../bindings/hwmon/maxim,max6639.yaml | 93 +++++++++++++++++++
1 file changed, 93 insertions(+)
create mode 100644 Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml
diff --git a/Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml b/Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml
new file mode 100644
index 000000000000..da040b11d2ab
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/maxim,max6639.yaml
@@ -0,0 +1,93 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+
+$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#
+
+ properties:
+ reg:
+ description: |
+ The fan number.
+ items:
+ minimum: 0
+ maximum: 1
+
+ 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
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v5 3/3] hwmon: (max6639) Change from pdata to dt configuration
2022-11-15 12:20 [PATCH v5 0/3] Add devicetree support for max6639 Naresh Solanki
2022-11-15 12:20 ` [PATCH v5 1/3] dt-bindings: hwmon: fan: Add fan binding to schema Naresh Solanki
2022-11-15 12:20 ` [PATCH v5 2/3] dt-bindings: hwmon: Add binding for max6639 Naresh Solanki
@ 2022-11-15 12:20 ` Naresh Solanki
2022-11-15 17:01 ` Uwe Kleine-König
2 siblings, 1 reply; 6+ messages in thread
From: Naresh Solanki @ 2022-11-15 12:20 UTC (permalink / raw)
To: devicetree, Guenter Roeck, Jean Delvare, Thierry Reding,
Uwe Kleine-König
Cc: linux-kernel, linux-hwmon, Patrick Rudolph, Naresh Solanki,
Marcello Sylvester Bauer, linux-pwm
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.
Non-DT platform can still use this module with its default
configuration.
Signed-off-by: Marcello Sylvester Bauer <sylv@sylv.io>
Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
---
drivers/hwmon/Kconfig | 1 +
drivers/hwmon/max6639.c | 465 +++++++++++++++++++++++++++++++++-------
2 files changed, 392 insertions(+), 74 deletions(-)
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 5695b266abcf..ad1f6742ca50 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1106,6 +1106,7 @@ 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 9b895402c80d..d1ae77e8f72e 100644
--- a/drivers/hwmon/max6639.c
+++ b/drivers/hwmon/max6639.c
@@ -19,7 +19,7 @@
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
-#include <linux/platform_data/max6639.h>
+#include <linux/pwm.h>
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
@@ -54,11 +54,20 @@ 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
+/* Tach supported range. This internally controls tach frequency */
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)
@@ -76,20 +85,24 @@ 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 */
- u8 pwm[2]; /* Register value: Duty cycle 0..120 */
u8 temp_therm[2]; /* THERM Temperature, 0..255 C (->_max) */
u8 temp_alert[2]; /* ALERT Temperature, 0..255 C (->_crit) */
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;
+ /* max6639 pwm chip */
+ struct pwm_chip chip;
};
static struct max6639_data *max6639_update_device(struct device *dev)
@@ -280,8 +293,12 @@ 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", pwm_get_relative_duty_cycle(&state, 255));
- return sprintf(buf, "%d\n", data->pwm[attr->index] * 255 / 120);
}
static ssize_t pwm_store(struct device *dev,
@@ -290,9 +307,9 @@ 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)
@@ -300,12 +317,12 @@ 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;
}
@@ -319,7 +336,7 @@ 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,
@@ -386,29 +403,41 @@ static struct attribute *max6639_attrs[] = {
ATTRIBUTE_GROUPS(max6639);
/*
- * returns respective index in rpm_ranges table
- * 1 by default on invalid range
+ * Get respective index in rpm_ranges table
*/
-static int rpm_range_to_reg(int range)
+static int rpm_range_to_index(struct device *dev, u8 *index, int rpm)
{
- int i;
-
- for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) {
- if (rpm_ranges[i] == range)
- return i;
+ if (rpm < 0)
+ return -EINVAL;
+
+ /* Set index based on chip support */
+ switch (rpm) {
+ case 0 ... 2000:
+ *index = 0;
+ break;
+ case 2001 ... 4000:
+ *index = 1;
+ break;
+ case 4001 ... 8000:
+ *index = 2;
+ break;
+ case 8001 ... 16000:
+ *index = 3;
+ break;
+ default:
+ /* Use max range for higher RPM */
+ dev_warn(dev,
+ "RPM higher than supported range. Default to 16000 RPM");
+ *index = 3;
}
-
- return 1; /* default: 4000 RPM */
+ return 0;
}
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;
+ struct pwm_state state;
/* Reset chip to default values, see below for GCONFIG setup */
err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
@@ -416,51 +445,29 @@ 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);
+ err = i2c_smbus_write_byte_data(client, MAX6639_REG_FAN_PPR(i),
+ 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);
- 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);
+ MAX6639_REG_FAN_CONFIG1(i),
+ MAX6639_FAN_CONFIG1_PWM |
+ data->rpm_range[i]);
if (err)
goto exit;
/*
- * /THERM full speed enable,
+ * /THERM full speed disable,
* PWM frequency 25kHz, see also GCONFIG below
*/
err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_FAN_CONFIG3(i),
- MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
+ MAX6639_REG_FAN_CONFIG3(i),
+ 0x03);
if (err)
goto exit;
@@ -469,31 +476,35 @@ static int max6639_init_client(struct i2c_client *client,
data->temp_alert[i] = 90;
data->temp_ot[i] = 100;
err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_THERM_LIMIT(i),
- data->temp_therm[i]);
+ MAX6639_REG_THERM_LIMIT(i),
+ data->temp_therm[i]);
if (err)
goto exit;
err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_ALERT_LIMIT(i),
- data->temp_alert[i]);
+ MAX6639_REG_ALERT_LIMIT(i),
+ data->temp_alert[i]);
if (err)
goto exit;
err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_OT_LIMIT(i), data->temp_ot[i]);
+ MAX6639_REG_OT_LIMIT(i),
+ data->temp_ot[i]);
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;
+
}
/* Start monitoring */
err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL |
MAX6639_GCONFIG_PWM_FREQ_HI);
+
exit:
return err;
}
@@ -524,12 +535,276 @@ 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;
+ }
+
+ err = rpm_range_to_index(dev, &data->rpm_range[i], maxrpm);
+ if (err) {
+ dev_err(dev, "invalid max-rpm %d of %pOFn\n", maxrpm, child);
+ return err;
+ }
+ data->max_rpm[i] = maxrpm;
+
+ 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)
+{
+ 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 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_ULL(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 = DIV_ROUND_UP_ULL(value * state->period,
+ 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;
+
+ pwm_get_state(pwm, &cstate);
+
+ 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 ((value & MAX6639_GCONFIG_PWM_FREQ_HI) && (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) {
+ value = DIV_ROUND_UP_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;
struct max6639_data *data;
struct device *hwmon_dev;
- int err;
+ int err, i;
data = devm_kzalloc(dev, sizeof(struct max6639_data), GFP_KERNEL);
if (!data)
@@ -537,11 +812,26 @@ 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;
+ data->chip.of_pwm_n_cells = 3;
+
+ err = devm_pwmchip_add(dev, &data->chip);
+ if (err < 0) {
+ dev_err(dev, "failed to add PWM chip %d\n", err);
+ return err;
+ }
+
data->reg = devm_regulator_get_optional(dev, "fan");
if (IS_ERR(data->reg)) {
- if (PTR_ERR(data->reg) != -ENODEV)
- return PTR_ERR(data->reg);
-
+ if (PTR_ERR(data->reg) != -ENODEV) {
+ err = (int)PTR_ERR(data->reg);
+ dev_warn(dev, "Failed looking up fan supply: %d\n",
+ err);
+ return err;
+ }
data->reg = NULL;
} else {
/* Spin up fans */
@@ -560,6 +850,22 @@ static int max6639_probe(struct i2c_client *client)
mutex_init(&data->update_lock);
+ /* Below are defaults leter overridden by DT properties */
+ for (i = 0; i < 2; i++) {
+ /* 4000 RPM */
+ data->rpm_range[i] = 1;
+ data->ppr[i] = 2;
+ /* Max. temp. 80C/90C/100C */
+ data->temp_therm[i] = 80;
+ data->temp_alert[i] = 90;
+ data->temp_ot[i] = 100;
+ }
+
+ /* 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)
@@ -571,6 +877,7 @@ static int max6639_probe(struct i2c_client *client)
return PTR_ERR_OR_ZERO(hwmon_dev);
}
+#if IS_ENABLED(CONFIG_PM_SLEEP)
static int max6639_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
@@ -608,6 +915,7 @@ static int max6639_resume(struct device *dev)
return i2c_smbus_write_byte_data(client,
MAX6639_REG_GCONFIG, ret & ~MAX6639_GCONFIG_STANDBY);
}
+#endif
static const struct i2c_device_id max6639_id[] = {
{"max6639", 0},
@@ -616,13 +924,22 @@ static const struct i2c_device_id max6639_id[] = {
MODULE_DEVICE_TABLE(i2c, max6639_id);
-static DEFINE_SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume);
+#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 SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume);
static struct i2c_driver max6639_driver = {
.class = I2C_CLASS_HWMON,
.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,
--
2.37.3
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v5 3/3] hwmon: (max6639) Change from pdata to dt configuration
2022-11-15 12:20 ` [PATCH v5 3/3] hwmon: (max6639) Change from pdata to dt configuration Naresh Solanki
@ 2022-11-15 17:01 ` Uwe Kleine-König
2022-11-15 20:58 ` Naresh Solanki
0 siblings, 1 reply; 6+ messages in thread
From: Uwe Kleine-König @ 2022-11-15 17:01 UTC (permalink / raw)
To: Naresh Solanki
Cc: devicetree, Guenter Roeck, Jean Delvare, Thierry Reding,
linux-kernel, linux-hwmon, Patrick Rudolph,
Marcello Sylvester Bauer, linux-pwm
[-- Attachment #1: Type: text/plain, Size: 23863 bytes --]
Hello,
On Tue, Nov 15, 2022 at 01:20:05PM +0100, Naresh Solanki wrote:
> 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.
My overall impression is that this patch mixes too much things. IMHO it
should be split in (at least)
- Add dt support
- Drop platform support
- Add PWM provider support
- Make use of the PWM API
maybe also add the 2nd PWM in a separate step.
Some more comments inline.
> Non-DT platform can still use this module with its default
> configuration.
>
> Signed-off-by: Marcello Sylvester Bauer <sylv@sylv.io>
> Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
> ---
> drivers/hwmon/Kconfig | 1 +
> drivers/hwmon/max6639.c | 465 +++++++++++++++++++++++++++++++++-------
> 2 files changed, 392 insertions(+), 74 deletions(-)
>
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 5695b266abcf..ad1f6742ca50 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -1106,6 +1106,7 @@ 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 9b895402c80d..d1ae77e8f72e 100644
> --- a/drivers/hwmon/max6639.c
> +++ b/drivers/hwmon/max6639.c
> @@ -19,7 +19,7 @@
> #include <linux/hwmon-sysfs.h>
> #include <linux/err.h>
> #include <linux/mutex.h>
> -#include <linux/platform_data/max6639.h>
This file is now unused and can be dropped.
> +#include <linux/pwm.h>
>
> /* Addresses to scan */
> static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
> @@ -54,11 +54,20 @@ 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
>
> +/* Tach supported range. This internally controls tach frequency */
> 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 };
I would have put these in a single line, or one line per freq, or at
least aligned the last value such that it is at a higher column than the
opening {.
> +
> +
> +
Three empty lines? One or two only should do it.
> #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)
> @@ -76,20 +85,24 @@ 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 */
> - u8 pwm[2]; /* Register value: Duty cycle 0..120 */
> u8 temp_therm[2]; /* THERM Temperature, 0..255 C (->_max) */
> u8 temp_alert[2]; /* ALERT Temperature, 0..255 C (->_crit) */
> 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;
> + /* max6639 pwm chip */
> + struct pwm_chip chip;
> };
>
> static struct max6639_data *max6639_update_device(struct device *dev)
> @@ -280,8 +293,12 @@ 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", pwm_get_relative_duty_cycle(&state, 255));
>
> - return sprintf(buf, "%d\n", data->pwm[attr->index] * 255 / 120);
> }
>
> static ssize_t pwm_store(struct device *dev,
> @@ -290,9 +307,9 @@ 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)
> @@ -300,12 +317,12 @@ 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;
> }
>
> @@ -319,7 +336,7 @@ 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,
> @@ -386,29 +403,41 @@ static struct attribute *max6639_attrs[] = {
> ATTRIBUTE_GROUPS(max6639);
>
> /*
> - * returns respective index in rpm_ranges table
> - * 1 by default on invalid range
> + * Get respective index in rpm_ranges table
> */
> -static int rpm_range_to_reg(int range)
> +static int rpm_range_to_index(struct device *dev, u8 *index, int rpm)
> {
> - int i;
> -
> - for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) {
> - if (rpm_ranges[i] == range)
> - return i;
> + if (rpm < 0)
> + return -EINVAL;
> +
> + /* Set index based on chip support */
> + switch (rpm) {
> + case 0 ... 2000:
> + *index = 0;
> + break;
> + case 2001 ... 4000:
> + *index = 1;
> + break;
> + case 4001 ... 8000:
> + *index = 2;
> + break;
> + case 8001 ... 16000:
> + *index = 3;
> + break;
> + default:
> + /* Use max range for higher RPM */
> + dev_warn(dev,
> + "RPM higher than supported range. Default to 16000 RPM");
> + *index = 3;
> }
> -
> - return 1; /* default: 4000 RPM */
> + return 0;
> }
>
> 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;
> + struct pwm_state state;
>
> /* Reset chip to default values, see below for GCONFIG setup */
> err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
> @@ -416,51 +445,29 @@ 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);
> + err = i2c_smbus_write_byte_data(client, MAX6639_REG_FAN_PPR(i),
> + 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);
> - 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);
> + MAX6639_REG_FAN_CONFIG1(i),
> + MAX6639_FAN_CONFIG1_PWM |
> + data->rpm_range[i]);
> if (err)
> goto exit;
>
> /*
> - * /THERM full speed enable,
> + * /THERM full speed disable,
> * PWM frequency 25kHz, see also GCONFIG below
> */
> err = i2c_smbus_write_byte_data(client,
> - MAX6639_REG_FAN_CONFIG3(i),
> - MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
> + MAX6639_REG_FAN_CONFIG3(i),
> + 0x03);
> if (err)
> goto exit;
>
> @@ -469,31 +476,35 @@ static int max6639_init_client(struct i2c_client *client,
> data->temp_alert[i] = 90;
> data->temp_ot[i] = 100;
> err = i2c_smbus_write_byte_data(client,
> - MAX6639_REG_THERM_LIMIT(i),
> - data->temp_therm[i]);
> + MAX6639_REG_THERM_LIMIT(i),
> + data->temp_therm[i]);
> if (err)
> goto exit;
> err = i2c_smbus_write_byte_data(client,
> - MAX6639_REG_ALERT_LIMIT(i),
> - data->temp_alert[i]);
> + MAX6639_REG_ALERT_LIMIT(i),
> + data->temp_alert[i]);
> if (err)
> goto exit;
> err = i2c_smbus_write_byte_data(client,
> - MAX6639_REG_OT_LIMIT(i), data->temp_ot[i]);
> + MAX6639_REG_OT_LIMIT(i),
> + data->temp_ot[i]);
> 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;
> +
> }
> /* Start monitoring */
> err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
> MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL |
> MAX6639_GCONFIG_PWM_FREQ_HI);
> +
> exit:
> return err;
> }
> @@ -524,12 +535,276 @@ 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;
> + }
> +
> + err = rpm_range_to_index(dev, &data->rpm_range[i], maxrpm);
> + if (err) {
> + dev_err(dev, "invalid max-rpm %d of %pOFn\n", maxrpm, child);
> + return err;
> + }
> + data->max_rpm[i] = maxrpm;
> +
> + 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;
Are these PWMs usuable at all for a consumer other than the driver
itself? If not I'd doubt the added value of this patch.
> + 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)
> +{
> + 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 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;
Please use pwm->hwpwm directly instead of i, this makes the code IMHO a
bit more readable.
> + 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_ULL(NSEC_PER_SEC, freq);
both NSEC_PER_SEC and freq fit into an unsigned int, so you can use the
(cheaper) DIV_ROUND_UP here.
> +
> + value = i2c_smbus_read_byte_data(client,
> + MAX6639_REG_TARGTDUTY(i));
> + if (value < 0)
> + goto abort;
> + /* max6639 supports 120 slots only */
> + state->duty_cycle = DIV_ROUND_UP_ULL(value * state->period,
> + 120);
s/120/MAX6639_REG_TARGTDUTY_SLOT/ ?
value * state->period might overflow. Use something like
mul_u64_u32_div. (Hmm, there doesn't seem to be a variant for unsigned *
unsigned / unsigned?)
You're loosing precision here. Consider freq = 8333 and TARGTDUTY = 97
then you have state->period = 120005 and calulate duty_cycle as:
DIV_ROUND_UP_ULL(97 * 120005, 120) = 97005
. The exact value is (I guess)
97 * NSEC_PER_SEC / (8333 * 120) = 97003.880
> + 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;
Please use pwm->hwpwm directly instead of i, this makes the code IMHO a
bit more readable.
> + unsigned int freq;
> + struct pwm_state cstate;
> +
> + pwm_get_state(pwm, &cstate);
Please don't use pwm API functions in PWM callbacks. Accessing
pwm->state is fine here.
> + 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;
For state->period = 80000 we get:
freq = 12500
and then x = 7 is picked while x = 6 would be an exact match.
I think you just need
if (freq <= freq_table[x])
> + 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 ((value & MAX6639_GCONFIG_PWM_FREQ_HI) && (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);
Why does it depend on MAX6639_GCONFIG_PWM_FREQ_HI being already set if
you need to set it?
> + if (value < 0)
> + goto abort;
> + }
> +
> + /* Configure dutycycle */
> + if (state->duty_cycle != cstate.duty_cycle) {
That check is wrong if you go from
.duty_cycle = 50000; .period = 200000
to
.duty_cycle = 50000; .period = 100000
> + value = DIV_ROUND_UP_ULL(
> + state->duty_cycle * MAX6639_REG_TARGTDUTY_SLOT,
> + state->period);
Please round down here. (And test with PWM_DEBUG which might have told
you given the right tests.) Also please use the real period to determine
the register value. (Otherwise for a request with
.duty_cycle = 40000; .period = 150000
where a real period of 120004.8 ns is picked you get
MAX6639_REG_TARGTDUTY_SLOT = 32 which results in a duty cycle of
32001.28 ns, while with MAX6639_REG_TARGTDUTY_SLOT = 39 you'd get
39001.56 ns.
> + 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;
Please use goto only for error handling.
> +
> + 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;
> struct max6639_data *data;
> struct device *hwmon_dev;
> - int err;
> + int err, i;
>
> data = devm_kzalloc(dev, sizeof(struct max6639_data), GFP_KERNEL);
> if (!data)
> @@ -537,11 +812,26 @@ 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;
> + data->chip.of_pwm_n_cells = 3;
Please drop this, of_pwmchip_add() overwrites it anyhow.
> +
> + err = devm_pwmchip_add(dev, &data->chip);
> + if (err < 0) {
> + dev_err(dev, "failed to add PWM chip %d\n", err);
dev_err_probe please.
> + return err;
> + }
> +
> data->reg = devm_regulator_get_optional(dev, "fan");
> if (IS_ERR(data->reg)) {
> - if (PTR_ERR(data->reg) != -ENODEV)
> - return PTR_ERR(data->reg);
> -
> + if (PTR_ERR(data->reg) != -ENODEV) {
> + err = (int)PTR_ERR(data->reg);
> + dev_warn(dev, "Failed looking up fan supply: %d\n",
> + err);
unrelated change. Also dev_probe_err is better suited here.
> + return err;
> + }
> data->reg = NULL;
> } else {
> /* Spin up fans */
> @@ -560,6 +850,22 @@ static int max6639_probe(struct i2c_client *client)
>
> mutex_init(&data->update_lock);
>
> + /* Below are defaults leter overridden by DT properties */
> + for (i = 0; i < 2; i++) {
> + /* 4000 RPM */
> + data->rpm_range[i] = 1;
> + data->ppr[i] = 2;
> + /* Max. temp. 80C/90C/100C */
> + data->temp_therm[i] = 80;
> + data->temp_alert[i] = 90;
> + data->temp_ot[i] = 100;
> + }
> +
> + /* 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)
> @@ -571,6 +877,7 @@ static int max6639_probe(struct i2c_client *client)
> return PTR_ERR_OR_ZERO(hwmon_dev);
> }
>
> +#if IS_ENABLED(CONFIG_PM_SLEEP)
unrelated change
> static int max6639_suspend(struct device *dev)
> {
> struct i2c_client *client = to_i2c_client(dev);
> @@ -608,6 +915,7 @@ static int max6639_resume(struct device *dev)
> return i2c_smbus_write_byte_data(client,
> MAX6639_REG_GCONFIG, ret & ~MAX6639_GCONFIG_STANDBY);
> }
> +#endif
>
> static const struct i2c_device_id max6639_id[] = {
> {"max6639", 0},
> @@ -616,13 +924,22 @@ static const struct i2c_device_id max6639_id[] = {
>
> MODULE_DEVICE_TABLE(i2c, max6639_id);
>
> -static DEFINE_SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume);
> +#ifdef CONFIG_OF
Note that ACPI also uses of_match_table.
> +static const struct of_device_id maxim_of_platform_match[] = {
> + {.compatible = "maxim,max6639"},
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, maxim_of_platform_match);
> +#endif
> +
> +static SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume);
>
> static struct i2c_driver max6639_driver = {
> .class = I2C_CLASS_HWMON,
> .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,
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | https://www.pengutronix.de/ |
[-- Attachment #2: signature.asc --]
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^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v5 3/3] hwmon: (max6639) Change from pdata to dt configuration
2022-11-15 17:01 ` Uwe Kleine-König
@ 2022-11-15 20:58 ` Naresh Solanki
0 siblings, 0 replies; 6+ messages in thread
From: Naresh Solanki @ 2022-11-15 20:58 UTC (permalink / raw)
To: Uwe Kleine-König
Cc: devicetree, Guenter Roeck, Jean Delvare, Thierry Reding,
linux-kernel, linux-hwmon, Patrick Rudolph,
Marcello Sylvester Bauer, linux-pwm
Hi Uwe,
On 15-11-2022 10:31 pm, Uwe Kleine-König wrote:
> Hello,
>
> On Tue, Nov 15, 2022 at 01:20:05PM +0100, Naresh Solanki wrote:
>> 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.
>
> My overall impression is that this patch mixes too much things. IMHO it
> should be split in (at least)
>
> - Add dt support
> - Drop platform support
> - Add PWM provider support
> - Make use of the PWM API
>
> maybe also add the 2nd PWM in a separate step.
>
> Some more comments inline.
>
>> Non-DT platform can still use this module with its default
>> configuration.
>>
>> Signed-off-by: Marcello Sylvester Bauer <sylv@sylv.io>
>> Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
>> ---
>> drivers/hwmon/Kconfig | 1 +
>> drivers/hwmon/max6639.c | 465 +++++++++++++++++++++++++++++++++-------
>> 2 files changed, 392 insertions(+), 74 deletions(-)
>>
>> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
>> index 5695b266abcf..ad1f6742ca50 100644
>> --- a/drivers/hwmon/Kconfig
>> +++ b/drivers/hwmon/Kconfig
>> @@ -1106,6 +1106,7 @@ 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 9b895402c80d..d1ae77e8f72e 100644
>> --- a/drivers/hwmon/max6639.c
>> +++ b/drivers/hwmon/max6639.c
>> @@ -19,7 +19,7 @@
>> #include <linux/hwmon-sysfs.h>
>> #include <linux/err.h>
>> #include <linux/mutex.h>
>> -#include <linux/platform_data/max6639.h>
>
> This file is now unused and can be dropped.
Sure in next version.
>
>> +#include <linux/pwm.h>
>>
>> /* Addresses to scan */
>> static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
>> @@ -54,11 +54,20 @@ 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
>>
>> +/* Tach supported range. This internally controls tach frequency */
>> 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 };
>
> I would have put these in a single line, or one line per freq, or at
> least aligned the last value such that it is at a higher column than the
> opening {.
Sure will align.
>
>> +
>> +
>> +
>
> Three empty lines? One or two only should do it.
Oh. Will correct this in next version.
>
>> #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)
>> @@ -76,20 +85,24 @@ 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 */
>> - u8 pwm[2]; /* Register value: Duty cycle 0..120 */
>> u8 temp_therm[2]; /* THERM Temperature, 0..255 C (->_max) */
>> u8 temp_alert[2]; /* ALERT Temperature, 0..255 C (->_crit) */
>> 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;
>> + /* max6639 pwm chip */
>> + struct pwm_chip chip;
>> };
>>
>> static struct max6639_data *max6639_update_device(struct device *dev)
>> @@ -280,8 +293,12 @@ 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", pwm_get_relative_duty_cycle(&state, 255));
>>
>> - return sprintf(buf, "%d\n", data->pwm[attr->index] * 255 / 120);
>> }
>>
>> static ssize_t pwm_store(struct device *dev,
>> @@ -290,9 +307,9 @@ 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)
>> @@ -300,12 +317,12 @@ 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;
>> }
>>
>> @@ -319,7 +336,7 @@ 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,
>> @@ -386,29 +403,41 @@ static struct attribute *max6639_attrs[] = {
>> ATTRIBUTE_GROUPS(max6639);
>>
>> /*
>> - * returns respective index in rpm_ranges table
>> - * 1 by default on invalid range
>> + * Get respective index in rpm_ranges table
>> */
>> -static int rpm_range_to_reg(int range)
>> +static int rpm_range_to_index(struct device *dev, u8 *index, int rpm)
>> {
>> - int i;
>> -
>> - for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) {
>> - if (rpm_ranges[i] == range)
>> - return i;
>> + if (rpm < 0)
>> + return -EINVAL;
>> +
>> + /* Set index based on chip support */
>> + switch (rpm) {
>> + case 0 ... 2000:
>> + *index = 0;
>> + break;
>> + case 2001 ... 4000:
>> + *index = 1;
>> + break;
>> + case 4001 ... 8000:
>> + *index = 2;
>> + break;
>> + case 8001 ... 16000:
>> + *index = 3;
>> + break;
>> + default:
>> + /* Use max range for higher RPM */
>> + dev_warn(dev,
>> + "RPM higher than supported range. Default to 16000 RPM");
>> + *index = 3;
>> }
>> -
>> - return 1; /* default: 4000 RPM */
>> + return 0;
>> }
>>
>> 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;
>> + struct pwm_state state;
>>
>> /* Reset chip to default values, see below for GCONFIG setup */
>> err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
>> @@ -416,51 +445,29 @@ 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);
>> + err = i2c_smbus_write_byte_data(client, MAX6639_REG_FAN_PPR(i),
>> + 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);
>> - 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);
>> + MAX6639_REG_FAN_CONFIG1(i),
>> + MAX6639_FAN_CONFIG1_PWM |
>> + data->rpm_range[i]);
>> if (err)
>> goto exit;
>>
>> /*
>> - * /THERM full speed enable,
>> + * /THERM full speed disable,
>> * PWM frequency 25kHz, see also GCONFIG below
>> */
>> err = i2c_smbus_write_byte_data(client,
>> - MAX6639_REG_FAN_CONFIG3(i),
>> - MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
>> + MAX6639_REG_FAN_CONFIG3(i),
>> + 0x03);
>> if (err)
>> goto exit;
>>
>> @@ -469,31 +476,35 @@ static int max6639_init_client(struct i2c_client *client,
>> data->temp_alert[i] = 90;
>> data->temp_ot[i] = 100;
>> err = i2c_smbus_write_byte_data(client,
>> - MAX6639_REG_THERM_LIMIT(i),
>> - data->temp_therm[i]);
>> + MAX6639_REG_THERM_LIMIT(i),
>> + data->temp_therm[i]);
>> if (err)
>> goto exit;
>> err = i2c_smbus_write_byte_data(client,
>> - MAX6639_REG_ALERT_LIMIT(i),
>> - data->temp_alert[i]);
>> + MAX6639_REG_ALERT_LIMIT(i),
>> + data->temp_alert[i]);
>> if (err)
>> goto exit;
>> err = i2c_smbus_write_byte_data(client,
>> - MAX6639_REG_OT_LIMIT(i), data->temp_ot[i]);
>> + MAX6639_REG_OT_LIMIT(i),
>> + data->temp_ot[i]);
>> 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;
>> +
>> }
>> /* Start monitoring */
>> err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
>> MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL |
>> MAX6639_GCONFIG_PWM_FREQ_HI);
>> +
>> exit:
>> return err;
>> }
>> @@ -524,12 +535,276 @@ 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;
>> + }
>> +
>> + err = rpm_range_to_index(dev, &data->rpm_range[i], maxrpm);
>> + if (err) {
>> + dev_err(dev, "invalid max-rpm %d of %pOFn\n", maxrpm, child);
>> + return err;
>> + }
>> + data->max_rpm[i] = maxrpm;
>> +
>> + 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;
>
> Are these PWMs usuable at all for a consumer other than the driver
> itself? If not I'd doubt the added value of this patch.
That depends on DT. For testing purpose, I specified different pwm
handle & those pwm unreference in DT where available for use via sysfs
export otherwise the resource was busy.
>
>> + 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)
>> +{
>> + 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 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;
>
> Please use pwm->hwpwm directly instead of i, this makes the code IMHO a
> bit more readable.
I used variable 'i' to make it look short. Can switch to pwm->hwpwm
>
>> + 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_ULL(NSEC_PER_SEC, freq);
>
> both NSEC_PER_SEC and freq fit into an unsigned int, so you can use the
> (cheaper) DIV_ROUND_UP here.
Sure. will update in next version
>
>> +
>> + value = i2c_smbus_read_byte_data(client,
>> + MAX6639_REG_TARGTDUTY(i));
>> + if (value < 0)
>> + goto abort;
>> + /* max6639 supports 120 slots only */
>> + state->duty_cycle = DIV_ROUND_UP_ULL(value * state->period,
>> + 120);
>
> s/120/MAX6639_REG_TARGTDUTY_SLOT/ ?
>
> value * state->period might overflow. Use something like
> mul_u64_u32_div. (Hmm, there doesn't seem to be a variant for unsigned *
> unsigned / unsigned?)
Yeah that seems better. Will update in next version
>
> You're loosing precision here. Consider freq = 8333 and TARGTDUTY = 97
> then you have state->period = 120005 and calulate duty_cycle as:
>
> DIV_ROUND_UP_ULL(97 * 120005, 120) = 97005
>
> . The exact value is (I guess)
>
> 97 * NSEC_PER_SEC / (8333 * 120) = 97003.880
>
For this chip, it may not matter as it supports only 120 slots.
>> + 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;
>
> Please use pwm->hwpwm directly instead of i, this makes the code IMHO a
> bit more readable.
I used variable 'i' to make it look short. Can switch to pwm->hwpwm
>
>> + unsigned int freq;
>> + struct pwm_state cstate;
>> +
>> + pwm_get_state(pwm, &cstate);
>
> Please don't use pwm API functions in PWM callbacks. Accessing
> pwm->state is fine here.
Sure.
>
>> + 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;
>
> For state->period = 80000 we get:
>
> freq = 12500
>
> and then x = 7 is picked while x = 6 would be an exact match.
>
> I think you just need
>
> if (freq <= freq_table[x])
>
Yes. Will update in next revision.
>> + 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 ((value & MAX6639_GCONFIG_PWM_FREQ_HI) && (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);
>
> Why does it depend on MAX6639_GCONFIG_PWM_FREQ_HI being already set if
> you need to set it?
>
Yes. Will update in next version
>> + if (value < 0)
>> + goto abort;
>> + }
>> +
>> + /* Configure dutycycle */
>> + if (state->duty_cycle != cstate.duty_cycle) {
>
> That check is wrong if you go from
>
> .duty_cycle = 50000; .period = 200000
>
> to
>
> .duty_cycle = 50000; .period = 100000
>
>
Yes. Will update in next revision.
>> + value = DIV_ROUND_UP_ULL(
>> + state->duty_cycle * MAX6639_REG_TARGTDUTY_SLOT,
>> + state->period);
>
> Please round down here. (And test with PWM_DEBUG which might have told
> you given the right tests.) Also please use the real period to determine
> the register value. (Otherwise for a request with
>
> .duty_cycle = 40000; .period = 150000
>
> where a real period of 120004.8 ns is picked you get
> MAX6639_REG_TARGTDUTY_SLOT = 32 which results in a duty cycle of
> 32001.28 ns, while with MAX6639_REG_TARGTDUTY_SLOT = 39 you'd get
> 39001.56 ns.
>
Sure will update to round down.
>> + 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;
>
> Please use goto only for error handling.
> >> +
>> + 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;
>> struct max6639_data *data;
>> struct device *hwmon_dev;
>> - int err;
>> + int err, i;
>>
>> data = devm_kzalloc(dev, sizeof(struct max6639_data), GFP_KERNEL);
>> if (!data)
>> @@ -537,11 +812,26 @@ 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;
>> + data->chip.of_pwm_n_cells = 3;
>
> Please drop this, of_pwmchip_add() overwrites it anyhow.
>
Sure.
>> +
>> + err = devm_pwmchip_add(dev, &data->chip);
>> + if (err < 0) {
>> + dev_err(dev, "failed to add PWM chip %d\n", err);
>
> dev_err_probe please.
>
Sure.
>> + return err;
>> + }
>> +
>> data->reg = devm_regulator_get_optional(dev, "fan");
>> if (IS_ERR(data->reg)) {
>> - if (PTR_ERR(data->reg) != -ENODEV)
>> - return PTR_ERR(data->reg);
>> -
>> + if (PTR_ERR(data->reg) != -ENODEV) {
>> + err = (int)PTR_ERR(data->reg);
>> + dev_warn(dev, "Failed looking up fan supply: %d\n",
>> + err);
>
> unrelated change. Also dev_probe_err is better suited here.
>
Sure.
>> + return err;
>> + }
>> data->reg = NULL;
>> } else {
>> /* Spin up fans */
>> @@ -560,6 +850,22 @@ static int max6639_probe(struct i2c_client *client)
>>
>> mutex_init(&data->update_lock);
>>
>> + /* Below are defaults leter overridden by DT properties */
>> + for (i = 0; i < 2; i++) {
>> + /* 4000 RPM */
>> + data->rpm_range[i] = 1;
>> + data->ppr[i] = 2;
>> + /* Max. temp. 80C/90C/100C */
>> + data->temp_therm[i] = 80;
>> + data->temp_alert[i] = 90;
>> + data->temp_ot[i] = 100;
>> + }
>> +
>> + /* 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)
>> @@ -571,6 +877,7 @@ static int max6639_probe(struct i2c_client *client)
>> return PTR_ERR_OR_ZERO(hwmon_dev);
>> }
>>
>> +#if IS_ENABLED(CONFIG_PM_SLEEP)
>
> unrelated change
>
Have put this to avoid error when CONFIG_PM_SLEEP is disabled.
>> static int max6639_suspend(struct device *dev)
>> {
>> struct i2c_client *client = to_i2c_client(dev);
>> @@ -608,6 +915,7 @@ static int max6639_resume(struct device *dev)
>> return i2c_smbus_write_byte_data(client,
>> MAX6639_REG_GCONFIG, ret & ~MAX6639_GCONFIG_STANDBY);
>> }
>> +#endif
>>
>> static const struct i2c_device_id max6639_id[] = {
>> {"max6639", 0},
>> @@ -616,13 +924,22 @@ static const struct i2c_device_id max6639_id[] = {
>>
>> MODULE_DEVICE_TABLE(i2c, max6639_id);
>>
>> -static DEFINE_SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume);
>> +#ifdef CONFIG_OF
>
> Note that ACPI also uses of_match_table.
>
>> +static const struct of_device_id maxim_of_platform_match[] = {
>> + {.compatible = "maxim,max6639"},
>> + {},
>> +};
>> +MODULE_DEVICE_TABLE(of, maxim_of_platform_match);
>> +#endif
>> +
>> +static SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume);
>>
>> static struct i2c_driver max6639_driver = {
>> .class = I2C_CLASS_HWMON,
>> .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,
>
> Best regards
> Uwe
>
Regards,
Naresh
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-11-15 20:58 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-11-15 12:20 [PATCH v5 0/3] Add devicetree support for max6639 Naresh Solanki
2022-11-15 12:20 ` [PATCH v5 1/3] dt-bindings: hwmon: fan: Add fan binding to schema Naresh Solanki
2022-11-15 12:20 ` [PATCH v5 2/3] dt-bindings: hwmon: Add binding for max6639 Naresh Solanki
2022-11-15 12:20 ` [PATCH v5 3/3] hwmon: (max6639) Change from pdata to dt configuration Naresh Solanki
2022-11-15 17:01 ` Uwe Kleine-König
2022-11-15 20:58 ` Naresh Solanki
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