Quoting Geert Uytterhoeven (2018-03-02 05:15:35)

Hi Mike,

On Sun, Feb 18, 2018 at 8:09 PM, Michael Turquette
[off-list ref] wrote:

quoted

Moving of_clk_get_parent_count to clk.h seems reasonable to me. It's
more of an of-specific helper than a provider-specific helper.

Anyone up to submit a patch so that this one doesn't need to include
clk-provider.h?

I gave it a try.
Just moving of_clk_get_parent_count() from clk-provider.h to clk.h causes
breakage, as half of the clock providers using of_clk_get_parent_count()
do not include <linux/clk.h>:

    drivers/clk/at91/clk-generated.c
    drivers/clk/at91/clk-main.c
    drivers/clk/at91/clk-master.c
    drivers/clk/at91/clk-programmable.c
    drivers/clk/at91/clk-slow.c
    drivers/clk/at91/clk-smd.c
    drivers/clk/at91/clk-usb.c
    drivers/clk/at91/sckc.c
    drivers/clk/clk-axi-clkgen.c
    drivers/clk/clk-gpio.c
    drivers/clk/clk-hsdk-pll.c
    drivers/clk/h8300/clk-div.c
    drivers/clk/h8300/clk-h8s2678.c
    drivers/clk/renesas/clk-div6.c
    drivers/clk/ti/composite.c
    drivers/clk/ti/gate.c
    drivers/clk/ti/mux.c

So our options are:
  1. Add #include <linux/clk.h> to each of the above,
  2. Add #include <linux/clk.h> to <linux/clk-provider.h>,
  3. Do nothing, i.e. users of of_clk_get_parent_count () need to
      #include <linux/clk-provider.h>, cfr. this patch series.

Any preference? Any option I'm missing?

#2 is a definite no.

How about option #4? Move of_clk_get_parent_count() and
of_clk_get_parent_name() to a new include/linux/of_clk.h, include that
in clk-provider.h, and then have non-clk provider drivers include that
file? After that, we can also move of_clk_init() into this new file, and
then non-provider arch code can call of_clk_init() without including the
provider APIs. I'd also like to get rid of the include of linux/of.h in
clk-provider.h, but that's a ways away.