This patch adds more error checking inn I2C I/O functions.
In case of I/O error, this permits to avoid writing in bad controller
pages, a bad chipset detection or looping when getting the EDID.
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Jean-Francois Moine <moinejf@free.fr> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>