Current code does not set correct slew rate in some cases:
e.g. Assume ramp_delay is 10000, current code sets slew register to 6mV/us.
Fix the logic to set slew register.
Signed-off-by: Axel Lin <axel.lin@ingics.com> Acked-by: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Mark Brown <broonie@kernel.org>