i2c: introduce device_i2c_driver() macro ...

Add macro and dependency to avoid boilerplate code. Since now simple
i2c drivers only have to include the i2c.h header and call the
device_i2c_driver() macro to register a i2c device driver.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

i2c-mux-pca954x: fix out-of-bounds write for 64 bit systems ...

get_drv_data(..., &data->type) overwrites memory beyond data->type member due
to mismatch of sizeof(enum pca_type) and sizeof(void *) on 64 bit systems.

Signed-off-by: Peter Mamonov <pmamonov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

i2c-mux-pca954x: Add code to control reset line ...

Most recent device tree binding for that mux support specifying a GPIO
connected to a reset line of that chip. Add code to handle that binding
in order to be able to use the chip on boards that leverage
aforementioned functionality.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

i2c: add pca954x bus multiplexer driver ...

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>