Re: [PATCH v4 3/7] misc: Add cros_ec_lpc driver for x86 devices

[Javier Martinez Canillas <javier.martinez@collabora.co.uk>]

Hello Paul,

Thanks a lot for your feedback.

On 01/29/2015 10:11 PM, Paul Bolle wrote:
>>  
>> +config CROS_EC_LPC
>> +	tristate "ChromeOS Embedded Controller (LPC)"
>> +	depends on MFD_CROS_EC
>> +
> 
> Please drop this empty line.
>

Ok.
 
>> +	help
>> +	  If you say Y here, you get support for talking to the ChromeOS EC
>> +	  over an LPC bus. This uses a simple byte-level protocol with a
>> +	  checksum. This is used for userspace access only. The kernel
>> +	  typically has its own communication methods.
>> +
> 
> What happens when you say M?
> 

Since it is a tristate kconfig symbol, it can be built as a kernel module
but since there isn't a LPC subsystem, the platform device is registered
in the module_init() function. So, building as a module is trickier since
there won't be an uevent that can trigger a module auto-load based on the
modinfo aliases information.

One can of course force udev to load the module by adding to modules.conf
or such but I wonder if is better to change from tristate to boolean or
add to the help that it can be built as a module but auto-load does not
work in that case.

Best regards,
Javier