Re: [PATCH V6 1/9] clk: imx: add gatable clock divider support

[Stephen Boyd]

Quoting A.s. Dong (2018-11-14 05:01:35)
> For dividers with zero indicating clock is disabled, instead of giving a
> warning each time like "clkx: Zero divisor and CLK_DIVIDER_ALLOW_ZERO not
> set" in exist code, we'd like to introduce enable/disable function for it.
> e.g.
> 000b - Clock disabled
> 001b - Divide by 1
> 010b - Divide by 2
> ...
> 
> Set rate when the clk is disabled will cache the rate request and only
> when the clk is enabled will the driver actually program the hardware to
> have the requested divider value. Similarly, when the clk is disabled we'll
> write a 0 there, but when the clk is enabled we'll restore whatever rate
> (divider) was chosen last.
> 
> It does mean that recalc rate will be sort of odd, because when the clk is
> off it will return 0, and when the clk is on it will return the right rate.
> So to make things work, we'll need to return the cached rate in recalc rate
> when the clk is off and read the hardware when the clk is on.
> 
> NOTE for the default off divider, the recalc rate will still return 0 as
> there's still no proper preset rate. Enable such divider will give user
> a reminder error message.
> 
> Cc: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
> Cc: Michael Turquette <mturquette@xxxxxxxxxxxx>
> Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
> Signed-off-by: Dong Aisheng <aisheng.dong@xxxxxxx>
> 
> ---

Applied to clk-next