Re: [PATCH] ds2782 battery gas gauge driver

[Anton Vorontsov <avorontsov@ru.mvista.com>]

On Wed, Jun 17, 2009 at 11:09:08AM +0200, Jean Delvare wrote:
> Hi Ryan,
> 
> On Tue, 16 Jun 2009 16:17:35 +1200, Ryan Mallon wrote:
> > Add support for the the ds2782 standalone I2C gas-gauge.
> > 
> > Signed-off-by: Ryan Mallon <ryan@bluewatersys.com>
> 
> I suggest you send this patch to the maintainers of the power supply
> subsystem for review: Anton Vorontsov and David Woodhouse (Cc'd.)

Thanks for Cc'ing and for the review, Jean.

[...]
> > +static int ds2782_get_temp(struct ds2782_info *info)
> > +{
> > +	u16 raw;
> > +	s16 temp;
> > +
> > +	/* Temperature is measured in units of 0.125 degrees celcius */
> > +	raw = ds2782_read_reg16(info, DS2782_REG_TEMP_MSB);
> > +	temp = (raw >> 5) & 0x7ff;
> > +	if (raw & (1 << 15))
> > +		temp |= 0xf800;
> > +	return (temp * 125) / 100;
> > +}
> 
> I don't know if the power supply class has a standard to reporting
> temperature values, but the hwmon class does, and it says that
> temperatures should be reported in millidegrees C. That's not what you
> do here AFAICS. It might be convenient to register a hwmon class device
> and export the temperature there, so that libsensors picks it.

Hwmon feels like a good idea. But no, drivers should not bother
with registering hwmon classes. Instead, some day we might want to
create power_supply_hwmon.c interface (like _sysfs.c that we have
already), the interface would register all needed stuff. And all
drivers will benefit right away without any modifications.

Thanks,

-- 
Anton Vorontsov
email: cbouatmailru@gmail.com
irc://irc.freenode.net/bd2