Re: [PATCH] dell-smm-hwmon: Detect fan with index=2

[Tolga Cakir <cevelnet@gmail.com>]

Hi Pali,

thanks for the patch and sorry for the delay! I've checked out
https://git.kernel.org/cgit/linux/kernel/git/groeck/linux-staging.git/commit/?h=hwmon-staging&id=86c050c82dd527b17cf47043831f03646f402a88
and ran it on my Dell M3800. It correctly works for identifying 2
fans, one listed as "Processor Fan" and the other as "Video Fan".

The freeze only causes "Processor Fan" to run at maximum btw., "Video
Fan" seems to be untouched. I don't get identical rpm values for both
of them, so they are indeed 2 independent fans. E.g. at ~70°C, I get
2300rpm for CPU and 2400rpm for Video. Looks good to me.

Cheers,
Tolga Cakir

2016-05-31 13:03 GMT+02:00 Pali Rohár <pali.rohar@gmail.com>:
> Tolga, can you test this patch if is working for you correctly?
>
> On Saturday 21 May 2016 16:52:46 Pali Rohár wrote:
>> Some Dell machines (e.g. Dell Precision M3800) have two fans, first with
>> index=0 and second with index=2. So export also attributes for third fan
>> device with index=2.
>>
>> Reported-by: Tolga Cakir <cevelnet@gmail.com>
>> Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
>> ---
>>  drivers/hwmon/dell-smm-hwmon.c |   20 +++++++++++++++++++-
>>  1 file changed, 19 insertions(+), 1 deletion(-)
>> ---
>>
>> Hi Tolga! Can you test this patch if sensors see fan device correctly?
>>
>> diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c
>> index 577445f..7a2764a 100644
>> --- a/drivers/hwmon/dell-smm-hwmon.c
>> +++ b/drivers/hwmon/dell-smm-hwmon.c
>> @@ -78,6 +78,7 @@ static uint i8k_fan_max = I8K_FAN_HIGH;
>>  #define I8K_HWMON_HAVE_TEMP4 (1 << 3)
>>  #define I8K_HWMON_HAVE_FAN1  (1 << 4)
>>  #define I8K_HWMON_HAVE_FAN2  (1 << 5)
>> +#define I8K_HWMON_HAVE_FAN3  (1 << 6)
>>
>>  MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
>>  MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
>> @@ -246,7 +247,7 @@ static int _i8k_get_fan_type(int fan)
>>  static int i8k_get_fan_type(int fan)
>>  {
>>       /* I8K_SMM_GET_FAN_TYPE SMM call is expensive, so cache values */
>> -     static int types[2] = { INT_MIN, INT_MIN };
>> +     static int types[3] = { INT_MIN, INT_MIN, INT_MIN };
>>
>>       if (types[fan] == INT_MIN)
>>               types[fan] = _i8k_get_fan_type(fan);
>> @@ -707,6 +708,12 @@ static SENSOR_DEVICE_ATTR(fan2_label, S_IRUGO, i8k_hwmon_show_fan_label, NULL,
>>                         1);
>>  static SENSOR_DEVICE_ATTR(pwm2, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
>>                         i8k_hwmon_set_pwm, 1);
>> +static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, i8k_hwmon_show_fan, NULL,
>> +                       2);
>> +static SENSOR_DEVICE_ATTR(fan3_label, S_IRUGO, i8k_hwmon_show_fan_label, NULL,
>> +                       2);
>> +static SENSOR_DEVICE_ATTR(pwm3, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm,
>> +                       i8k_hwmon_set_pwm, 2);
>>
>>  static struct attribute *i8k_attrs[] = {
>>       &sensor_dev_attr_temp1_input.dev_attr.attr,     /* 0 */
>> @@ -723,6 +730,9 @@ static struct attribute *i8k_attrs[] = {
>>       &sensor_dev_attr_fan2_input.dev_attr.attr,      /* 11 */
>>       &sensor_dev_attr_fan2_label.dev_attr.attr,      /* 12 */
>>       &sensor_dev_attr_pwm2.dev_attr.attr,            /* 13 */
>> +     &sensor_dev_attr_fan3_input.dev_attr.attr,      /* 14 */
>> +     &sensor_dev_attr_fan3_label.dev_attr.attr,      /* 15 */
>> +     &sensor_dev_attr_pwm3.dev_attr.attr,            /* 16 */
>>       NULL
>>  };
>>
>> @@ -747,6 +757,9 @@ static umode_t i8k_is_visible(struct kobject *kobj, struct attribute *attr,
>>       if (index >= 11 && index <= 13 &&
>>           !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN2))
>>               return 0;
>> +     if (index >= 14 && index <= 16 &&
>> +         !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN3))
>> +             return 0;
>>
>>       return attr->mode;
>>  }
>> @@ -788,6 +801,11 @@ static int __init i8k_init_hwmon(void)
>>       if (err >= 0)
>>               i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN2;
>>
>> +     /* Third fan attributes, if fan status is OK */
>> +     err = i8k_get_fan_status(2);
>> +     if (err >= 0)
>> +             i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN3;
>> +
>>       i8k_hwmon_dev = hwmon_device_register_with_groups(NULL, "dell_smm",
>>                                                         NULL, i8k_groups);
>>       if (IS_ERR(i8k_hwmon_dev)) {
>
> --
> Pali Rohár
> pali.rohar@gmail.com