In current code, the tick count value programmed to the hardware is
always decremented by one. This is reasonable for periodic mode, since
there is one extra tick between 0 and COUNT (after reloading), but it
makes oneshot events happen 1 tick earlier than requested, because the
interrupt is triggered on transition from 1 to 0.

This patch removes the decrementation from PWM channel setup code and
moves it instead to periodic timer setup, to make both periodic and
oneshot modes work correctly.
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Olof Johansson <olof@lixom.net>