Re: All device tree bindings need maintainer ack or just the 'interesting' ones.

[Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>]

On Tue, 17 Sep 2013, Mark Rutland wrote:

> On Tue, Sep 17, 2013 at 01:07:30PM +0100, Lee Jones wrote:
> > On Tue, 17 Sep 2013, Mark Rutland wrote:
> > 
> > > On Tue, Sep 17, 2013 at 09:10:03AM +0100, Lee Jones wrote:
> > > > > > http://marc.info/?l=linux-iio&m=137881790217809&w=2
> > > > > 
> > > > > Looks reasonable. My only comment is '-' is preferred over '_'.
> > > > 
> > > > Ah, in the node name you mean. Yes, I can change that.
> > > > 
> > > > The compatible string has to stay the same however, as it has to match
> > > > the device name which can't be changed due to possible userspace
> > > > breakage.
> > > 
> > > I'm not sure I follow why the compatible string must be identical to the
> > > name appearing to userspace.
> > 
> > It doesn't. It has to be identical to the device name, which I'm
> > guessing is used when populating sysfs.
> 
> I still don't understand why the device name must be identical to the
> compatible string.
> 
> The string "st,lsm303dlh_magn" (with the "st," prefix) appears nowhere
> in v3.12-rc1

You're looking at an old patchset. We found out that the Snowball
schematic was actually incorrect and we have a LSM303DLHC.

git grep -i lsm303dlhc_magn v3.12-rc1
  drivers/iio/magnetometer/st_magn.h:
    #define LSM303DLHC_MAGN_DEV_NAME   "lsm303dlhc_magn"

> and the compatible string in the dt doesn't seem to get
> assigned to the device in the i2c core or in
> drivers/iio/magnetometer/st_magn_i2c.c.

It does:
  drivers/i2c/busses/*.c: of_i2c_register_devices();
  drivers/of/of_i2c.c:    |-> of_modalias_node();
                            |-> i2c_new_device();

> I don't see how the "st,lsm303dlh_magn" string could be getting to
> userspace already such that it could be relying on it.
> 
> Am I missing something?
> 
> Thanks,
> Mark.
> 
> > 

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html