For 'normal' i2c bus drivers, we can call of_i2c_register_devices()
and have the device tree framework automatically populate the bus with
the devices specified in the device tree.

This patch adds a common code to the i2c mux framework to have the mux
sub-busses be populated by the of_i2c_register_devices() too.  If the
mux device has an of_node, we populate the sub-bus' of_node so that
the subsequent call to of_i2c_register_devices() will find the
corresponding devices.

It seemed better to put this logic in i2c_add_mux_adapter() rather
than the individual mux drivers, as they will all probably want to do
the same thing.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Acked-by: NStephen Warren <swarren@wwwdotorg.org>
Tested-by: NLars-Peter Clausen <lars@metafoo.de>

[wsa: removed superfluous ret-variable and fixed a typo in a comment]
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>

And adjust all callers.

The new device parameter is used in the next patch to initialize the
mux's of_node so that its children may be automatically populated.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Tested-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>

It's about time to make it clear that i2c_adapter.id is deprecated.
Hopefully this will remind the last user to move over to a different
strategy.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NJarod Wilson <jarod@redhat.com>
Acked-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: NHans Verkuil <hverkuil@xs4all.nl>

Add multiplexed bus core support. I2C multiplexer and switches
like pca954x get instantiated as new adapters per port.
Signed-off-by: NMichael Lawnick <ml.lawnick@gmx.de>
Acked-by: NRodolfo Giometti <giometti@linux.it>
Signed-off-by: NJean Delvare <khali@linux-fr.org>