Extend the public API of clock_control driver with a function for
querying of clock rate driving given peripheral. This is useful when the
driver must calculate or configurae values that depend on the rate of
clock driving this subsystem.
A baud rate setting of UART port is an example of such operation. To
configure a particular baud rate the driver may need to set the internal
counters of UART port, where the actual value will depend on the clock
rate for this peripheral.
The implementation returns DEV_NO_SUPPORT for clock_control drivers that
do not implement such functionality.
Change-Id: I4e7ec96cd3678a4bb1ff289b0247488289310f2d
Origin: Original
Signed-off-by: Maciej Borzecki <maciek.borzecki@gmail.com>
Quark SE provides various clock controllers through its SCSS block.
Peripheral, external, sensor, and others.
This current drivers provides only the clock gating capability, for
peripheral, external and sensor. But it could support divider and more
other features once defined in the generic API.
Note: such clock has _nothing_ to do with a Real Time Clock (RTC).
An RTC provide clock timing like a watch would do. Here the clock
controller is about circuit clocking.
Change-Id: I1a365ae730dfc6be7686271f7fbb693e64a6ff6f
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>