On Mon, Nov 21, 2022 at 01:29:31PM +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.
>
This patch does way more than that.
> Signed-off-by: Marcello Sylvester Bauer <sylv@xxxxxxx>
> Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>
> ---
> drivers/hwmon/max6639.c | 246 +++++++++++++++++++-------
> include/linux/platform_data/max6639.h | 15 --
> 2 files changed, 178 insertions(+), 83 deletions(-)
> delete mode 100644 include/linux/platform_data/max6639.h
>
> diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c
> index 9b895402c80d..feafa3511297 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 };
> @@ -54,9 +53,12 @@ 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 };
>
> #define FAN_FROM_REG(val, rpm_range) ((val) == 0 || (val) == 255 ? \
> @@ -76,18 +78,21 @@ 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 */
> + u32 target_rpm[2];
> + u32 max_rpm[2];
> + u8 pwm[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 */
> + u8 pwm_polarity[2];
> /* Optional regulator for FAN supply */
> struct regulator *reg;
> };
> @@ -282,6 +287,7 @@ static ssize_t pwm_show(struct device *dev, struct device_attribute *dev_attr,
> struct max6639_data *data = dev_get_drvdata(dev);
>
> return sprintf(buf, "%d\n", data->pwm[attr->index] * 255 / 120);
> +
Unnecessary and wrong whitespace change.
> }
>
> static ssize_t pwm_store(struct device *dev,
> @@ -302,10 +308,10 @@ static ssize_t pwm_store(struct device *dev,
>
> 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]);
> + i2c_smbus_write_byte_data(client, MAX6639_REG_TARGTDUTY(attr->index),
> + data->pwm[attr->index]);
> mutex_unlock(&data->update_lock);
> +
> return count;
Unnecessary formatting change. You may not like the original formatting,
but that is no reason to change it.
> }
>
> @@ -319,7 +325,7 @@ 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 +392,40 @@ 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;
The above changes are unrelated to $subject. Also, the same could be
accomplished by varying the range check in the for loop, making the
change POV. The warning is both unacceptable and unnecessary.
> }
>
> 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,
> @@ -416,51 +433,29 @@ 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]);
The above change silently drops the configuration of
MAX6639_REG_FAN_CONFIG2a, which is puzzling since the patch
also introduces MAX6639_REG_FAN_CONFIG2a_PWM_POL which isn't
used. I don't see what this has to do with $subject, and the
lack of explanation is not really reassuring.
> if (err)
> goto exit;
>
> /*
> - * /THERM full speed enable,
> + * /THERM full speed disable,
Change unrelated to $subject and possibly unexpected results
for users of this driver.
> * 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 +464,34 @@ 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]);
Unrelated formatting changes above. Such changes just obfuscate functional
changes made in the patch and are unacceptable. If you want to fix
checkpatch issues, do it in a separate patch.
I am stopping the review here. In the future, please refrain from making
unrelated changes. One logical change per patch, please.
Guenter
> 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]);
> + data->pwm[i] = data->target_rpm[i];
> + err = i2c_smbus_write_byte_data(client, MAX6639_REG_TARGTDUTY(i), data->pwm[i]);
> +
> 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 +522,95 @@ 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;
> +
> + 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;
> 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)
> @@ -539,9 +620,11 @@ static int max6639_probe(struct i2c_client *client)
>
> 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);
> + return dev_err_probe(dev, err,
> + "Failed looking up fan supply\n");
> + }
> data->reg = NULL;
> } else {
> /* Spin up fans */
> @@ -560,6 +643,22 @@ static int max6639_probe(struct i2c_client *client)
>
> mutex_init(&data->update_lock);
>
> + /* Below are defaults later 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 +670,7 @@ 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 +708,7 @@ 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 +717,22 @@ 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,
> 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 */
