Re: [PATCHv1 1/3] hwmon: Add support for GMT G762/G763 PWM fan controller

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

On Wed, Apr 24, 2013 at 10:28:47PM +0200, Arnaud Ebalard wrote:
> Hi,
> 
> Guenter Roeck <linux@roeck-us.net> writes:
> 
> >> > You could consider using regmap for holding this cache.
> >> >
> >> > http://elceurope2012.sched.org/event/100619b669ce5767341624253aa03659?iframe=no&w=900&sidebar=yes&bg=no#.UXdspHLQ5jM
> >> >
> >> > http://elinux.org/ELCE_Europe_2012_Presentations
> >> 
> >> Interesting. As I am not yet familiar w/ regmap I would prefer having
> >> the driver accepted during merge window with current data structure and
> >> then convert it to regmap. But I will take a look (e.g. will study
> >> fca1dd03 for instance). Thanks for the pointers. 
> >> 
> > I have not had time for a detailed review, but adding regmap support
> > will not be a requirement.
> >
> > Note that it is too late for 3.10, so the driver will have to wait for
> > 3.11.
> 
> Well, I think I can live with it; The only bad thing is that it kills my
> excuses not to spend time on regmap ;-)
> 
Your call.

> 
> >> >> +/*
> >> >> + * Helpers to import hardware characteristics from .dts file and overload
> >> >> + * default config values.
> >> >> + */
> >> >> +
> >> >> +#ifdef CONFIG_OF
> >> >
> >> > Can the driver be used without device tree? Would it be simpler to
> >> >  just add depends OF in the Kconfig entry?
> >> 
> >> It can be used if the default params (or those configured by u-boot I
> >> guess) fit your needs. I think it would be fairly easy to extend the
> >> driver later to expose g762_config struct to allow parameters to be set
> >> w/o using OF. If someone wants to do that, I think it is better to not
> >> depend on OF in Kconfig at the moment but I have not strong argument
> >> other that that one. I'll let you decide.
> >> 
> > Agreed. As long as there are major platforms not supporting device tree,
> > and as long as device tree overlays are not supported, it must not be made
> > mandatory. Especially for I2C and SPI devices I reserve the right to be able
> > test the hardware on an X86 system and not require a reboot to do so.
> 
> Understood. Following Simon's post, I think it's useful to implement
> some init function for non DT-enabled platforms. 
> 
Sure, as long as Simon commits to test it and - if possible - to provide
the necessary platform code.

Guenter