diff mbox series

[v4,2/2] hwmon: (max6639) : Add hwmon attributes for fan and pwm

Message ID 20240604124742.4093334-2-naresh.solanki@9elements.com (mailing list archive)
State Changes Requested
Headers show
Series [v4,1/2] hwmon: (max6639) : Update hwmon init using info structure | expand

Commit Message

Naresh Solanki June 4, 2024, 12:47 p.m. UTC 
Add attribute for fan & pwm i.e.,
fanY_pulse
pwmY_freq

Signed-off-by: Naresh Solanki <naresh.solanki@9elements.com>
---
 drivers/hwmon/max6639.c | 74 ++++++++++++++++++++++++++++++++++++++---
 1 file changed, 70 insertions(+), 4 deletions(-)

Comments

Guenter Roeck June 12, 2024, 3:55 p.m. UTC | #1 
On 6/4/24 05:47, Naresh Solanki wrote:
> Add attribute for fan & pwm i.e.,
> fanY_pulse
> pwmY_freq
> 
> Signed-off-by: Naresh Solanki <naresh.solanki@9elements.com>
> ---
>   drivers/hwmon/max6639.c | 74 ++++++++++++++++++++++++++++++++++++++---
>   1 file changed, 70 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c
> index e2a5210f9f95..6c7eaeeb2a80 100644
> --- a/drivers/hwmon/max6639.c
> +++ b/drivers/hwmon/max6639.c
> @@ -235,6 +235,9 @@ static int max6639_read_fan(struct device *dev, u32 attr, int channel,
>   			return res;
>   		*fan_val = !!(val & BIT(1 - channel));
>   		return 0;
> +	case hwmon_fan_pulses:
> +		*fan_val = data->ppr[channel];
> +		return 0;
>   	default:
>   		return -EOPNOTSUPP;
>   	}
> @@ -246,6 +249,32 @@ static int max6639_set_ppr(struct max6639_data *data, int channel, u8 ppr)
>   	return regmap_write(data->regmap, MAX6639_REG_FAN_PPR(channel), ppr-- << 6);
>   }
>   
> +static int max6639_write_fan(struct device *dev, u32 attr, int channel,
> +			     long val)
> +{
> +	struct max6639_data *data = dev_get_drvdata(dev);
> +	int err;
> +
> +	if (IS_ERR(data))
> +		return PTR_ERR(data);
> +

Unnecessary check.

> +	switch (attr) {
> +	case hwmon_fan_pulses:
> +		if (val <= 0 || val > 5)
> +			return -EINVAL;
> +
> +		/* Set Fan pulse per revolution */
> +		err = max6639_set_ppr(data, channel, val);
> +		if (err < 0)
> +			return err;
> +
> +		data->ppr[channel] = val;

Needs mutex protection to avoid inconsistencies due to concurrent writes.

> +		return 0;
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +}
> +
>   static umode_t max6639_fan_is_visible(const void *_data, u32 attr, int channel)
>   {
>   	struct max6639_data *data = (struct max6639_data *)_data;
> @@ -270,6 +299,7 @@ static int max6639_read_pwm(struct device *dev, u32 attr, int channel,
>   	struct max6639_data *data = dev_get_drvdata(dev);
>   	unsigned int val;
>   	int res;
> +	u8 i;
>   
>   	if (IS_ERR(data))
>   		return PTR_ERR(data);
> @@ -281,6 +311,21 @@ static int max6639_read_pwm(struct device *dev, u32 attr, int channel,
>   			return res;
>   		*pwm_val = val * 255 / 120;
>   		return 0;
> +	case hwmon_pwm_freq:
> +		res = regmap_read(data->regmap, MAX6639_REG_FAN_CONFIG3(channel), &val);
> +		if (res < 0)
> +			return res;
> +		i = val & MAX6639_FAN_CONFIG3_FREQ_MASK;
> +
> +		res = regmap_read(data->regmap, MAX6639_REG_GCONFIG, &val);
> +		if (res < 0)
> +			return res;
> +
> +		if (val & MAX6639_GCONFIG_PWM_FREQ_HI)
> +			i |= 0x4;

This sequence will need to be mutex protected to avoid consistency errors if
a write happens at the same time.


> +		i &= 0x7;
> +		*pwm_val = freq_table[i];
> +		return 0;
>   	default:
>   		return -EOPNOTSUPP;
>   	}
> @@ -291,6 +336,7 @@ static int max6639_write_pwm(struct device *dev, u32 attr, int channel,
>   {
>   	struct max6639_data *data = dev_get_drvdata(dev);
>   	int err;
> +	u8 i;
>   
>   	if (IS_ERR(data))
>   		return PTR_ERR(data);
> @@ -301,6 +347,23 @@ static int max6639_write_pwm(struct device *dev, u32 attr, int channel,
>   		err = regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(channel),
>   				   val * 120 / 255);
>   		return err;
> +	case hwmon_pwm_freq:
> +		val = clamp_val(val, 0, 25000);
> +
> +		i = find_closest(val, freq_table, ARRAY_SIZE(freq_table));
> +
> +		err = regmap_update_bits(data->regmap, MAX6639_REG_FAN_CONFIG3(channel),
> +					 MAX6639_FAN_CONFIG3_FREQ_MASK, i);
> +		if (err < 0)
> +			return err;
> +
> +		if (i >> 2)
> +			err = regmap_set_bits(data->regmap, MAX6639_REG_GCONFIG,
> +					      MAX6639_GCONFIG_PWM_FREQ_HI);
> +		else
> +			err = regmap_clear_bits(data->regmap, MAX6639_REG_GCONFIG,
> +						MAX6639_GCONFIG_PWM_FREQ_HI);

Same as above. In general, every operation with more than a single element
needs to be mutex protected.

> +		return err;
>   	default:
>   		return -EOPNOTSUPP;
>   	}
> @@ -310,6 +373,7 @@ static umode_t max6639_pwm_is_visible(const void *_data, u32 attr, int channel)
>   {
>   	switch (attr) {
>   	case hwmon_pwm_input:
> +	case hwmon_pwm_freq:
>   		return 0644;
>   	default:
>   		return 0;
> @@ -415,6 +479,8 @@ static int max6639_write(struct device *dev, enum hwmon_sensor_types type,
>   			 u32 attr, int channel, long val)
>   {
>   	switch (type) {
> +	case hwmon_fan:
> +		return max6639_write_fan(dev, attr, channel, val);
>   	case hwmon_pwm:
>   		return max6639_write_pwm(dev, attr, channel, val);
>   	case hwmon_temp:
> @@ -442,11 +508,11 @@ static umode_t max6639_is_visible(const void *data,
>   
>   static const struct hwmon_channel_info * const max6639_info[] = {
>   	HWMON_CHANNEL_INFO(fan,
> -			   HWMON_F_INPUT | HWMON_F_FAULT,
> -			   HWMON_F_INPUT | HWMON_F_FAULT),
> +			   HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_PULSES,
> +			   HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_PULSES),
>   	HWMON_CHANNEL_INFO(pwm,
> -			   HWMON_PWM_INPUT,
> -			   HWMON_PWM_INPUT),
> +			   HWMON_PWM_INPUT | HWMON_PWM_FREQ,
> +			   HWMON_PWM_INPUT | HWMON_PWM_FREQ),
>   	HWMON_CHANNEL_INFO(temp,
>   			   HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_MAX | HWMON_T_MAX_ALARM |
>   			   HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_EMERGENCY |
Naresh Solanki June 13, 2024, 9:51 a.m. UTC | #2 
Hi Guenter,

On Wed, 12 Jun 2024 at 21:25, Guenter Roeck <linux@roeck-us.net> wrote:
>
> On 6/4/24 05:47, Naresh Solanki wrote:
> > Add attribute for fan & pwm i.e.,
> > fanY_pulse
> > pwmY_freq
> >
> > Signed-off-by: Naresh Solanki <naresh.solanki@9elements.com>
> > ---
> >   drivers/hwmon/max6639.c | 74 ++++++++++++++++++++++++++++++++++++++---
> >   1 file changed, 70 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c
> > index e2a5210f9f95..6c7eaeeb2a80 100644
> > --- a/drivers/hwmon/max6639.c
> > +++ b/drivers/hwmon/max6639.c
> > @@ -235,6 +235,9 @@ static int max6639_read_fan(struct device *dev, u32 attr, int channel,
> >                       return res;
> >               *fan_val = !!(val & BIT(1 - channel));
> >               return 0;
> > +     case hwmon_fan_pulses:
> > +             *fan_val = data->ppr[channel];
> > +             return 0;
> >       default:
> >               return -EOPNOTSUPP;
> >       }
> > @@ -246,6 +249,32 @@ static int max6639_set_ppr(struct max6639_data *data, int channel, u8 ppr)
> >       return regmap_write(data->regmap, MAX6639_REG_FAN_PPR(channel), ppr-- << 6);
> >   }
> >
> > +static int max6639_write_fan(struct device *dev, u32 attr, int channel,
> > +                          long val)
> > +{
> > +     struct max6639_data *data = dev_get_drvdata(dev);
> > +     int err;
> > +
> > +     if (IS_ERR(data))
> > +             return PTR_ERR(data);
> > +
>
> Unnecessary check.
Ack.
>
> > +     switch (attr) {
> > +     case hwmon_fan_pulses:
> > +             if (val <= 0 || val > 5)
> > +                     return -EINVAL;
> > +
> > +             /* Set Fan pulse per revolution */
> > +             err = max6639_set_ppr(data, channel, val);
> > +             if (err < 0)
> > +                     return err;
> > +
> > +             data->ppr[channel] = val;
>
> Needs mutex protection to avoid inconsistencies due to concurrent writes.
This is single i2c access. Still we need mutex protection here ?
>
> > +             return 0;
> > +     default:
> > +             return -EOPNOTSUPP;
> > +     }
> > +}
> > +
> >   static umode_t max6639_fan_is_visible(const void *_data, u32 attr, int channel)
> >   {
> >       struct max6639_data *data = (struct max6639_data *)_data;
> > @@ -270,6 +299,7 @@ static int max6639_read_pwm(struct device *dev, u32 attr, int channel,
> >       struct max6639_data *data = dev_get_drvdata(dev);
> >       unsigned int val;
> >       int res;
> > +     u8 i;
> >
> >       if (IS_ERR(data))
> >               return PTR_ERR(data);
> > @@ -281,6 +311,21 @@ static int max6639_read_pwm(struct device *dev, u32 attr, int channel,
> >                       return res;
> >               *pwm_val = val * 255 / 120;
> >               return 0;
> > +     case hwmon_pwm_freq:
> > +             res = regmap_read(data->regmap, MAX6639_REG_FAN_CONFIG3(channel), &val);
> > +             if (res < 0)
> > +                     return res;
> > +             i = val & MAX6639_FAN_CONFIG3_FREQ_MASK;
> > +
> > +             res = regmap_read(data->regmap, MAX6639_REG_GCONFIG, &val);
> > +             if (res < 0)
> > +                     return res;
> > +
> > +             if (val & MAX6639_GCONFIG_PWM_FREQ_HI)
> > +                     i |= 0x4;
>
> This sequence will need to be mutex protected to avoid consistency errors if
> a write happens at the same time.
Ack. Yes, there is multiple access to the device. Will update accordingly.
>
>
> > +             i &= 0x7;
> > +             *pwm_val = freq_table[i];
> > +             return 0;
> >       default:
> >               return -EOPNOTSUPP;
> >       }
> > @@ -291,6 +336,7 @@ static int max6639_write_pwm(struct device *dev, u32 attr, int channel,
> >   {
> >       struct max6639_data *data = dev_get_drvdata(dev);
> >       int err;
> > +     u8 i;
> >
> >       if (IS_ERR(data))
> >               return PTR_ERR(data);
> > @@ -301,6 +347,23 @@ static int max6639_write_pwm(struct device *dev, u32 attr, int channel,
> >               err = regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(channel),
> >                                  val * 120 / 255);
> >               return err;
> > +     case hwmon_pwm_freq:
> > +             val = clamp_val(val, 0, 25000);
> > +
> > +             i = find_closest(val, freq_table, ARRAY_SIZE(freq_table));
> > +
> > +             err = regmap_update_bits(data->regmap, MAX6639_REG_FAN_CONFIG3(channel),
> > +                                      MAX6639_FAN_CONFIG3_FREQ_MASK, i);
> > +             if (err < 0)
> > +                     return err;
> > +
> > +             if (i >> 2)
> > +                     err = regmap_set_bits(data->regmap, MAX6639_REG_GCONFIG,
> > +                                           MAX6639_GCONFIG_PWM_FREQ_HI);
> > +             else
> > +                     err = regmap_clear_bits(data->regmap, MAX6639_REG_GCONFIG,
> > +                                             MAX6639_GCONFIG_PWM_FREQ_HI);
>
> Same as above. In general, every operation with more than a single element
> needs to be mutex protected.
Ack.

Regards,
Naresh
>
> > +             return err;
> >       default:
> >               return -EOPNOTSUPP;
> >       }
> > @@ -310,6 +373,7 @@ static umode_t max6639_pwm_is_visible(const void *_data, u32 attr, int channel)
> >   {
> >       switch (attr) {
> >       case hwmon_pwm_input:
> > +     case hwmon_pwm_freq:
> >               return 0644;
> >       default:
> >               return 0;
> > @@ -415,6 +479,8 @@ static int max6639_write(struct device *dev, enum hwmon_sensor_types type,
> >                        u32 attr, int channel, long val)
> >   {
> >       switch (type) {
> > +     case hwmon_fan:
> > +             return max6639_write_fan(dev, attr, channel, val);
> >       case hwmon_pwm:
> >               return max6639_write_pwm(dev, attr, channel, val);
> >       case hwmon_temp:
> > @@ -442,11 +508,11 @@ static umode_t max6639_is_visible(const void *data,
> >
> >   static const struct hwmon_channel_info * const max6639_info[] = {
> >       HWMON_CHANNEL_INFO(fan,
> > -                        HWMON_F_INPUT | HWMON_F_FAULT,
> > -                        HWMON_F_INPUT | HWMON_F_FAULT),
> > +                        HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_PULSES,
> > +                        HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_PULSES),
> >       HWMON_CHANNEL_INFO(pwm,
> > -                        HWMON_PWM_INPUT,
> > -                        HWMON_PWM_INPUT),
> > +                        HWMON_PWM_INPUT | HWMON_PWM_FREQ,
> > +                        HWMON_PWM_INPUT | HWMON_PWM_FREQ),
> >       HWMON_CHANNEL_INFO(temp,
> >                          HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_MAX | HWMON_T_MAX_ALARM |
> >                          HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_EMERGENCY |
>
Guenter Roeck June 13, 2024, 1:44 p.m. UTC | #3 
On 6/13/24 02:51, Naresh Solanki wrote:
...
>>
>>> +     switch (attr) {
>>> +     case hwmon_fan_pulses:
>>> +             if (val <= 0 || val > 5)
>>> +                     return -EINVAL;
>>> +
>>> +             /* Set Fan pulse per revolution */
>>> +             err = max6639_set_ppr(data, channel, val);
>>> +             if (err < 0)
>>> +                     return err;
>>> +
>>> +             data->ppr[channel] = val;
>>
>> Needs mutex protection to avoid inconsistencies due to concurrent writes.
> This is single i2c access. Still we need mutex protection here ?

In this case, the mutex doesn't protect the i2c access, it protects the
consistency between the chip configuration and the information stored
in data->ppr[].

CPU1			CPU2
[val==1]		[val!=1]

max6639_set_ppr();
			max6639_set_ppr();
			data->ppr[channel] = val;
data->ppr[channel] = val;

The alternative would be to not cache ppr and read it from the regmap cache
when needed.

Guenter
diff mbox series

Patch

diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c
index e2a5210f9f95..6c7eaeeb2a80 100644
--- a/drivers/hwmon/max6639.c
+++ b/drivers/hwmon/max6639.c
@@ -235,6 +235,9 @@  static int max6639_read_fan(struct device *dev, u32 attr, int channel,
 			return res;
 		*fan_val = !!(val & BIT(1 - channel));
 		return 0;
+	case hwmon_fan_pulses:
+		*fan_val = data->ppr[channel];
+		return 0;
 	default:
 		return -EOPNOTSUPP;
 	}
@@ -246,6 +249,32 @@  static int max6639_set_ppr(struct max6639_data *data, int channel, u8 ppr)
 	return regmap_write(data->regmap, MAX6639_REG_FAN_PPR(channel), ppr-- << 6);
 }
 
+static int max6639_write_fan(struct device *dev, u32 attr, int channel,
+			     long val)
+{
+	struct max6639_data *data = dev_get_drvdata(dev);
+	int err;
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	switch (attr) {
+	case hwmon_fan_pulses:
+		if (val <= 0 || val > 5)
+			return -EINVAL;
+
+		/* Set Fan pulse per revolution */
+		err = max6639_set_ppr(data, channel, val);
+		if (err < 0)
+			return err;
+
+		data->ppr[channel] = val;
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
 static umode_t max6639_fan_is_visible(const void *_data, u32 attr, int channel)
 {
 	struct max6639_data *data = (struct max6639_data *)_data;
@@ -270,6 +299,7 @@  static int max6639_read_pwm(struct device *dev, u32 attr, int channel,
 	struct max6639_data *data = dev_get_drvdata(dev);
 	unsigned int val;
 	int res;
+	u8 i;
 
 	if (IS_ERR(data))
 		return PTR_ERR(data);
@@ -281,6 +311,21 @@  static int max6639_read_pwm(struct device *dev, u32 attr, int channel,
 			return res;
 		*pwm_val = val * 255 / 120;
 		return 0;
+	case hwmon_pwm_freq:
+		res = regmap_read(data->regmap, MAX6639_REG_FAN_CONFIG3(channel), &val);
+		if (res < 0)
+			return res;
+		i = val & MAX6639_FAN_CONFIG3_FREQ_MASK;
+
+		res = regmap_read(data->regmap, MAX6639_REG_GCONFIG, &val);
+		if (res < 0)
+			return res;
+
+		if (val & MAX6639_GCONFIG_PWM_FREQ_HI)
+			i |= 0x4;
+		i &= 0x7;
+		*pwm_val = freq_table[i];
+		return 0;
 	default:
 		return -EOPNOTSUPP;
 	}
@@ -291,6 +336,7 @@  static int max6639_write_pwm(struct device *dev, u32 attr, int channel,
 {
 	struct max6639_data *data = dev_get_drvdata(dev);
 	int err;
+	u8 i;
 
 	if (IS_ERR(data))
 		return PTR_ERR(data);
@@ -301,6 +347,23 @@  static int max6639_write_pwm(struct device *dev, u32 attr, int channel,
 		err = regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(channel),
 				   val * 120 / 255);
 		return err;
+	case hwmon_pwm_freq:
+		val = clamp_val(val, 0, 25000);
+
+		i = find_closest(val, freq_table, ARRAY_SIZE(freq_table));
+
+		err = regmap_update_bits(data->regmap, MAX6639_REG_FAN_CONFIG3(channel),
+					 MAX6639_FAN_CONFIG3_FREQ_MASK, i);
+		if (err < 0)
+			return err;
+
+		if (i >> 2)
+			err = regmap_set_bits(data->regmap, MAX6639_REG_GCONFIG,
+					      MAX6639_GCONFIG_PWM_FREQ_HI);
+		else
+			err = regmap_clear_bits(data->regmap, MAX6639_REG_GCONFIG,
+						MAX6639_GCONFIG_PWM_FREQ_HI);
+		return err;
 	default:
 		return -EOPNOTSUPP;
 	}
@@ -310,6 +373,7 @@  static umode_t max6639_pwm_is_visible(const void *_data, u32 attr, int channel)
 {
 	switch (attr) {
 	case hwmon_pwm_input:
+	case hwmon_pwm_freq:
 		return 0644;
 	default:
 		return 0;
@@ -415,6 +479,8 @@  static int max6639_write(struct device *dev, enum hwmon_sensor_types type,
 			 u32 attr, int channel, long val)
 {
 	switch (type) {
+	case hwmon_fan:
+		return max6639_write_fan(dev, attr, channel, val);
 	case hwmon_pwm:
 		return max6639_write_pwm(dev, attr, channel, val);
 	case hwmon_temp:
@@ -442,11 +508,11 @@  static umode_t max6639_is_visible(const void *data,
 
 static const struct hwmon_channel_info * const max6639_info[] = {
 	HWMON_CHANNEL_INFO(fan,
-			   HWMON_F_INPUT | HWMON_F_FAULT,
-			   HWMON_F_INPUT | HWMON_F_FAULT),
+			   HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_PULSES,
+			   HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_PULSES),
 	HWMON_CHANNEL_INFO(pwm,
-			   HWMON_PWM_INPUT,
-			   HWMON_PWM_INPUT),
+			   HWMON_PWM_INPUT | HWMON_PWM_FREQ,
+			   HWMON_PWM_INPUT | HWMON_PWM_FREQ),
 	HWMON_CHANNEL_INFO(temp,
 			   HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_MAX | HWMON_T_MAX_ALARM |
 			   HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_EMERGENCY |