clk: cs2000-cp: add support for dynamic mode
The CS2000 chip features two input clocks, REF_CLK and CLK_IN.
In static mode, the output clock (CLK_OUT) is directly derived from
REF_CLK, and CLK_IN is ignored. In dynamic mode, CLK_IN is used by the
digital PLL.
In dynamic mode, a low-frequency ratio configuration that uses a higher
multiplier factor.
Until now, only the static mode and high-frequency divider rations of
the hardware was supported by the driver. This patch adds support for
dynamic mode and both ratios:
* Parse a new OF property 'cirrus,dynamic-mode' to determine the mode
* In dynamic mode, present CLK_IN as parent clock, else use REF_CLK
* The low-frequency ratio mode is automatically selected, depending
on the mode of operation and the given input and output rates
Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20220125093336.226787-7-daniel@zonque.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>