Add support of rs485 delay in nanoseconds.
With fast data rates (1Mbaut or more), 1ms become quite long. Users need
to be able to set shorter delays than 1 ms in order not to slow down the
channel unnecessarily. This enables faster communication channels without
changing the baudrate.
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Signed-off-by: Borut Seljak <borut.seljak@t-2.net>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Change-Id: I72cdf03197b7c3abfc1f2fa0c03e91b665461be1
8fe0cd660f