Re: sysfs: Initialization order and system devices

[Patrick Mochel]

On 11 Jun 2003, Jeremy Fitzhardinge wrote:

> With the current system device changes (I picked them up in 2.5.70-mm8),
> the system device class assumes that all system device drivers are
> registered before any system devices are registered.
> 
> Unfortunately, this is often not the case.  CPU devices are registered
> very early, but cpufreq registers drivers for them; since cpufreq
> drivers can be loaded as modules, they clearly can't be registered
> before the device is.
> 
> This patch keeps a list of all registered devices hanging off the system
> device class.  When a new driver is registered, it calls the driver's
> add() function with all existing devices.
> 
> Conversely, when a driver is unregistered, it calls the driver's
> remove() function for all existing devices so the driver can clean up.

D'oh. I meant to add this piece for precisely this reason. Thanks, though 
there is one thing: 

+
+       /* If devices of this class already exist, tell the driver */
+       if (drv->add) {
+               struct sys_device *dev;
+               list_for_each_entry(dev, &cls->devices, entry)
+                       drv->add(dev);
+       }
+

in sysdev_driver_register(). You must check that cls is not NULL. I've 
fixed it up and applied it.

Thanks,

	-pat