[lm-sensors] [0/6] New w1 features.

[dmitry.torokhov@gmail.com (Dmitry Torokhov)]

On 6/3/05, Evgeniy Polyakov <johnpol@2ka.mipt.ru> wrote:
> On Fri, 3 Jun 2005 17:12:16 -0500
> Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote:
> 
> > On 6/3/05, Evgeniy Polyakov <johnpol@2ka.mipt.ru> wrote:
> > > On Fri, 3 Jun 2005 16:46:48 -0500
> > > Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote:
> > >
> > > > On 6/3/05, Evgeniy Polyakov <johnpol@2ka.mipt.ru> wrote:
> > > > >
> > > > > 6. I wrote reconnect feature: if on start there are no
> > > > > registered families all new devices will have defailt family,
> > > > > later when driver for appropriate family is loaded, slaves,
> > > > > which were faound earlier, will still have defult family instead
> > > > > of right one. Reconnect feature will force control thread to
> > > > > run through all master devices and all slaves found
> > > > > and search for slaves with default family id and try to reconnect
> > > > > them.
> > > >
> > > > Yep, start with one kludge and you'll end up with 10 more.
> > > >
> > > > Would you mind explaining why a w1 device has to be bound to a family
> > > > before it can show in sysfs? We don't have such limitation on other
> > > > buses, why is it needed for w1?
> > >
> > > Because w1 device does not have any sence without appropriate family driver.
> > > You may have a device without a driver for it.
> > > All buses support it - see dmesg when new device was added but there is
> > > no driver for that - usb bus magically says slot is used.
> > > Here is the same.
> > >
> >
> > You still have not answered the question - why a family (i.e. a
> > driver) is needed? I have bunch of PCI devices in my box that don't
> > have drivers and they show up in sysfs just fine. The same with other
> > buses.
> >
> > As it stands now you decided that you won't show devices without a
> > driver - then you realized that a "default" driver is needed - then
> > you realized that you need to reconnect when you load a "specialized"
> > driver. That's why I am saying start with one kludge and you'll end up
> > with 10 more.
> 
> I hope you are kidding comparing PCI and w1.
> lspci just shows PCI config space access.
> w1 does not have nothing similar to it,
> so you just may not access w1 device like you can access PCI.
> In w1 there is no interrupt which can inform w1 bus master
> that there is a new device like in USB.

It does not matter. Master scans wire - master finds device - master
adds device. The fact that it does not have driver (family) is
irrelevant here.

-- 
Dmitry