Re: i8k: move driver from char to hwmon

[Guenter Roeck <linux@roeck-us.net>]

On 02/22/2015 09:44 AM, Pali Rohár wrote:
> On Sunday 22 February 2015 18:33:16 Guenter Roeck wrote:
>> On 02/22/2015 03:50 AM, Pali Rohár wrote:
>>> Hello,
>>>
>>> currently i8k driver for DELLDIAG SMM operations (charger,
>>> battery, hotkeys, temperature and fan control) supports two
>>> interfaces:
>>>
>>> 1) old /proc/i8k char device
>>> 2) new hwmon interface
>>>
>>> Driver now lives in char subsystem, but nowadays I think lot
>>> of people are interested only in hwmon interface which
>>> provides temperature & fan control. Power management and
>>> hotkeys support (which is missing in 2) but provided by 1))
>>> is already handled by ACPI or input subsystem for new
>>> laptops.
>>>
>>> Also name "i8k" is really non intuitive what it means and
>>> supports... (I was told it is abbreviation for Inspirion
>>> 8000 model which was probably first dell model supported by
>>> that DELLDIAG interface). Now driver is used on Vostro,
>>> Latitude and also Precision and XPS models. I think at
>>> least "dell" should be part of driver name and config
>>> option.
>>>
>>> So I have idea for some changes:
>>>
>>> 1) Move driver from char subsystem to hwmon
>>
>> I am ok with this one.
>>
>>> 2) Rename driver from i8k to something like delldiag or
>>> dellsmm
>>
>> Might be problematic, as it would break existing
>> configurations unless you keep the CONFIG_I8K but rename the
>> driver. Driver names are never perfect, so I would just leave
>> it as is.
>>
>>> 3) Add new CONFIG_ option to enable/disable /proc/i8k device
>>> and compile only hwmon interface support
>>
>> Makes sense. I would suggest to make hwmon suppport the
>> default and mandatory if the driver is enabled and add a new
>> CONFIG_I8K_PROCIF or similar which should be enabled by
>> default.
>>
>
> What about CONFIG_DELLDIAG (or DELLSMM or CONFIG_SENSORS_*) for
> mandatory core & hwmon code and (keep existing) CONFIG_I8K for
> /proc/i8k?
>
CONFIG_SENSORS_DELL would probably be best, but that would still
break backward compatibility for existing configurations unless
you enable CONFIG_SENSORS_DELL by default which would not be
a good idea.

Guenter