If the I2C bus master driver does not support the required functionality,
the driver returns -ENODEV. This causes a silent probe failure without error
message. Since the device has to be explicitly instantiated, and the user
should know the correct bus, this event really reflects an error condition.
Replace error return value with -EINVAL to trigger an error message showing
that the probe function failed.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

This driver adds support for NXP SC18IS602/603 I2C to SPI bus bridge.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>