Re: qestion about I2C_CLASS_HWMON flag

Jean Delvare
2008-09-05T13:50:11Z

On Fri, 5 Sep 2008 15:38:23 +0200, Francis Moreau wrote:
> On Fri, Sep 5, 2008 at 3:11 PM, Jean Delvare <khali@linux-fr.org> wrote:
> > It's not about hacking, it can be done cleanly. Just have the adapter
> > driver code check for information in the platform data, and if class
> > information is provided, use that instead of the default value. Or if
> > all users will provide the information, don't even have a default in
> > the driver. Again, the class flags are a (needed) mechanism, the policy
> > is left for driver authors and platform maintainers to establish.
>
> Ah OK I see now.
>
> On v2.6.23 i2c-gpio.c had no I2C_CLASS_HWMON flag set and
> had no way to pass this info from platform board.
>
> But on v2.6.27 it is now set whatever the platforms.
>
> Wouldn't it have been better to allow the platform code to pass this type
> information through the 'i2c_gpio_platform_data' structure for example ?

If you have a need for that, sure. If you don't, that's making the code
more complex for no good reason.

I expect I2C_CLASS_HWMON to be removed from that driver soon. Now that
almost all hwmon drivers have been converted to support instantiated
I2C devices, and given that all users of i2c-gpio are embedded
architectures with platform code, it should be no longer needed. But
again I am leaving it to whoever is actually using this driver to
decide what is best for them.

--
Jean Delvare