On 06/18/2012 04:50 PM, Stephen Warren wrote:

quoted

Can you please tell in which way the patch breaks those drivers?
However, I can see that those drivers solved the same problem in a
different way (deferring of_get_named_gpio(), via the sound init()). So
they could be adjusted to take advantage of new -EPROBE_DEFER.

The drivers I mentioned test the return code of of_get_named_gpio() to
see if it's -ENODEV, which means that DT property for that GPIO exists
but the driver for it isn't available yet, so the property can't be
parsed. In this case, the sound drivers defer their own probe. If
of_get_named_gpio() is modified to return -EPROBE_DEFER directly, then
it won't be returning -ENODEV, and hence the sound drivers' check for
-ENODEV won't fire, and hence the sound drivers will just continue their
probe assuming that the particular GPIOs are not present on the board
(since they are all optional, so anything other than an explicit
deferral error from of_get_named_gpio() is not treated as an error).
This will break sound on those platforms.

Thanks for the hint! I previously also suspected sth. like this but
didn't find it in v3.5-rc3. In broonie's sound.git for-next, I now
finally found it.

Should be easy to fix (replacing the if (... == -ENODEV) to -EPROBE_DEFER.

Will you provide patches as signalled, of should I? Which branch would
be the correct one to build on top?

Thanks in advance,

Roland