[i2c] [PATCH 2/5] i2c: Allow preallocation of I2C bus numbers.

[David Brownell]

On Friday 18 May 2007, Scott Wood wrote:
> Scott Wood wrote:
> > David Brownell wrote:
> >> You couldn't register a device that's already in the device tree.
> >>
> >> So the only concern is whether your drivers, or configuration,
> >> is buggy ... nothing new!
> > 
> > 
> > So is it considered a bug to have drivers turned on that you don't need 
> > on this specific target?  Suppose I have a new-style 1374 driver, and an 
> > old-style 1307 driver.  They both use address 0x68.  The only way for 
> > the 1374 driver to get there before the 1307 driver erroneously claims 
> > the device is to preregister.
> 
> As an alternative, what about a flag that an adapter could set 
> indicating that legacy drivers should not be probed?

That doesn't seem like a characteristic of the adapter as much
as one of a board configuration which wrongly includes two drivers
for the same device.  Simpler to not include the legacy driver...

Example, I have boards where not all the I2C drivers have new-style
drivers available.  I couldn't realistically set that flag; but it's
simple not to configure non-legacy drivers.


> Upon further thought, making i2c_register_board_info() usable from a 
> module would require some way to remove the module's contribution to the 
> list upon module removal, which is more trouble than it's worth.

Yes, that's one of the problems.

- Dave