This is useful for SoCs whose I2C module's signals can be routed to
different sets of pins at run-time, using the pinctrl API.
+-----+ +-----+
| dev | | dev |
+------------------------+ +-----+ +-----+
| SoC | | |
| /----|------+--------+
| +---+ +------+ | child bus A, on first set of pins
| |I2C|---|Pinmux| |
| +---+ +------+ | child bus B, on second set of pins
| \----|------+--------+--------+
| | | | |
+------------------------+ +-----+ +-----+ +-----+
| dev | | dev | | dev |
+-----+ +-----+ +-----+
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>