[lm-sensors] [PATCH] hwmon: (max1668) Add support for tempX_fault attributes

[Jean Delvare]

Hi Guenter,

On Thu, 9 Jun 2011 18:14:07 -0700, Guenter Roeck wrote:
> MAX1668 and compatibles have several external temperature sensors, but only
> a single FAULT status bit. If a fault occurs, the temperature reported on
> affected sensors is 127 degrees C. Use this knowledge to report faults on
> individual external sensors.
> 
> Signed-off-by: Guenter Roeck <guenter.roeck at ericsson.com>
> ---
> Tested with MAX1668 with one sensor disconnected. Resulting output is as follows.
> Seems to be better than just reporting extra-high temperature.

Looks overall good.

Acked-by: Jean Delvare <khali at linux-fr.org>

Minor comments below if you are interested.

As a side note, it seems that
http://git.kernel.org/?p=linux/kernel/git/groeck/staging.git;a=commit;h=af2dcfe730577d5399973a4df648190f5562b470
doesn't properly credit David as being the original author of the
commit.

> 
> root at groeck-desktop# sensors
> max1668-i2c-5-18
> Adapter: i2c-devantech-iss at bus 001 device 007
> temp1:        +23.0°C  (low  = -55.0°C, high = +127.0°C)
> temp2:        +25.0°C  (low  = -55.0°C, high = +127.0°C)
> temp3:        +25.0°C  (low  = -55.0°C, high = +127.0°C)
> temp4:        +25.0°C  (low  = -55.0°C, high = +127.0°C)
> temp5:          FAULT  (low  = -55.0°C, high = +127.0°C)    ALARM(MAX)
> 
>  drivers/hwmon/max1668.c |   26 +++++++++++++++++++++++++-
>  1 files changed, 25 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/hwmon/max1668.c b/drivers/hwmon/max1668.c
> index ddefb64..af85d44 100644
> --- a/drivers/hwmon/max1668.c
> +++ b/drivers/hwmon/max1668.c
> @@ -123,7 +123,7 @@ static struct max1668_data *max1668_update_device(struct device *dev)
>  		goto abort;
>  	}
>  	data->alarms &= 0x00ff;
> -	data->alarms |= ((u8) (val & 0x60)) << 8;
> +	data->alarms |= ((u8) (val & 0x70)) << 8;

The (u8) type cast doesn't seem needed. Same a few lines below for
MAX1668_REG_STAT2.

>  
>  	val = i2c_smbus_read_byte_data(client, MAX1668_REG_STAT2);
>  	if (unlikely(val < 0)) {
> @@ -189,6 +189,19 @@ static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
>  	return sprintf(buf, "%u\n", (data->alarms >> index) & 0x1);
>  }
>  
> +static ssize_t show_fault(struct device *dev,
> +			  struct device_attribute *devattr, char *buf)
> +{
> +	int index = to_sensor_dev_attr(devattr)->index;
> +	struct max1668_data *data = max1668_update_device(dev);
> +
> +	if (IS_ERR(data))
> +		return PTR_ERR(data);
> +
> +	return sprintf(buf, "%d\n",

%u would probably make more sense, as this is used for alarms above.
But I agree %d will work too.

> +		       (data->alarms & (1 << 12)) && data->temp[index] == 127);
> +}
> +
>  static ssize_t set_temp_max(struct device *dev,
>  			    struct device_attribute *devattr,
>  			    const char *buf, size_t count)
> @@ -276,6 +289,11 @@ static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 2);
>  static SENSOR_DEVICE_ATTR(temp5_min_alarm, S_IRUGO, show_alarm, NULL, 1);
>  static SENSOR_DEVICE_ATTR(temp5_max_alarm, S_IRUGO, show_alarm, NULL, 0);
>  
> +static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_fault, NULL, 1);
> +static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_fault, NULL, 2);
> +static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_fault, NULL, 3);
> +static SENSOR_DEVICE_ATTR(temp5_fault, S_IRUGO, show_fault, NULL, 4);
> +
>  /* Attributes common to MAX1668, MAX1989 and MAX1805 */
>  static struct attribute *max1668_attribute_common[] = {
>  	&sensor_dev_attr_temp1_max.dev_attr.attr,
> @@ -294,6 +312,9 @@ static struct attribute *max1668_attribute_common[] = {
>  	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
>  	&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
>  	&sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
> +
> +	&sensor_dev_attr_temp2_fault.dev_attr.attr,
> +	&sensor_dev_attr_temp3_fault.dev_attr.attr,
>  	NULL
>  };
>  
> @@ -310,6 +331,9 @@ static struct attribute *max1668_attribute_unique[] = {
>  	&sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
>  	&sensor_dev_attr_temp5_max_alarm.dev_attr.attr,
>  	&sensor_dev_attr_temp5_min_alarm.dev_attr.attr,
> +
> +	&sensor_dev_attr_temp4_fault.dev_attr.attr,
> +	&sensor_dev_attr_temp5_fault.dev_attr.attr,
>  	NULL
>  };
>  


-- 
Jean Delvare