[PATCH v3 2/3] clk: divider: Switch from .round_rate to .determine_rate by default

[Martin Blumenstingl]

Hi Stephen,

On Fri, Jul 2, 2021 at 3:02 AM Stephen Boyd <sboyd at kernel.org> wrote:
[...]
> My guess is that we have drivers copying the clk_ops from the
> divider_ops structure and so they are copying over round_rate but not
> determine_rate.
I just learned something new - thanks for investigating this as well!

$ git grep "clk_divider_ops\.round_rate" drivers/
drivers/clk/bcm/clk-bcm2835.c:  return clk_divider_ops.round_rate(hw,
rate, parent_rate);
drivers/clk/clk-stm32f4.c:      return clk_divider_ops.round_rate(hw,
rate, prate);
drivers/clk/clk-stm32h7.c:      return clk_divider_ops.round_rate(hw,
rate, prate);
drivers/clk/clk-stm32mp1.c:             req->rate =
clk_divider_ops.round_rate(hw, req->rate, &best_parent_rate);
drivers/clk/imx/clk-divider-gate.c:     return
clk_divider_ops.round_rate(hw, rate, prate);
$ git grep "clk_divider_ro_ops\.round_rate" drivers/
$

Changing these over to use clk_divider_ops.determine_rate doesn't seem too hard.
The part that I am not sure about is how to organize the patches.
1) amend the changes to all relevant drivers (from above) to this patch
2) multiple patches:
- adding .determine_rate to the default divider ops (but not removing
.round_rate)
- a single patch for each relevant driver (from above)
- removing .round_rate from the default divider ops

Another approach is to first create clk_divider_determine_rate() (as
done here) and export it.
Then I could have one individual patch for each relevant driver (from
above) to use:
  .determine_rate = clk_divider_determine_rate,
Then finally I could remove clk_divider_round_rate() and switch over
the default divider ops to .determine_rate as well.

Which way do you prefer?


Best regards,
Martin