diff mbox

[2/3] soc: rockchip: power-domain: Use of_clk_get_parent_count() instead of open coding

Message ID 1516375101-29836-3-git-send-email-geert+renesas@glider.be (mailing list archive)
State New, archived
Headers show

Commit Message

Geert Uytterhoeven Jan. 19, 2018, 3:18 p.m. UTC
As of_clk_get_parent_count() returns zero on failure, while
of_count_phandle_with_args() might return a negative error code, this
also fixes the issue of possibly using a negative number in the
allocation below.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/soc/rockchip/pm_domains.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Heiko Stuebner Feb. 10, 2018, 4:35 p.m. UTC | #1
Hi Geert,

Am Freitag, 19. Januar 2018, 16:18:20 CET schrieb Geert Uytterhoeven:
> As of_clk_get_parent_count() returns zero on failure, while
> of_count_phandle_with_args() might return a negative error code, this
> also fixes the issue of possibly using a negative number in the
> allocation below.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
>  drivers/soc/rockchip/pm_domains.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/soc/rockchip/pm_domains.c b/drivers/soc/rockchip/pm_domains.c
> index 5c342167b9db7a16..9936038d38771784 100644
> --- a/drivers/soc/rockchip/pm_domains.c
> +++ b/drivers/soc/rockchip/pm_domains.c
> @@ -16,6 +16,7 @@
>  #include <linux/of_address.h>
>  #include <linux/of_platform.h>
>  #include <linux/clk.h>
> +#include <linux/clk-provider.h>

not wanting to be to nitpicky, but clk-provider.h seems that it should be
used from drivers exposing clocks to the system, not from clock users.

I just remember that in the past clk maintainers tried to keep their
layering intact, so I've included them for clarification.

Mike, Stephen: the power-domain driver of Rockchip socs needs
to toggle all clocks of domain peripherals when turning a domain
on or off, so has a variable list of clocks in the clocks property in dt.
Hence the of_count_... call which could be replaced with
of_clk_get_parent_count to not open-code this.


Heiko

>  #include <linux/regmap.h>
>  #include <linux/mfd/syscon.h>
>  #include <dt-bindings/power/rk3288-power.h>
> @@ -391,7 +392,7 @@ static int rockchip_pm_add_one_domain(struct rockchip_pmu *pmu,
>  		return -EINVAL;
>  	}
>  
> -	clk_cnt = of_count_phandle_with_args(node, "clocks", "#clock-cells");
> +	clk_cnt = of_clk_get_parent_count(node);
>  	pd = devm_kzalloc(pmu->dev,
>  			  sizeof(*pd) + clk_cnt * sizeof(pd->clks[0]),
>  			  GFP_KERNEL);
>
Michael Turquette Feb. 18, 2018, 7:09 p.m. UTC | #2
Heiko, Geert,

On Sat, Feb 10, 2018 at 8:35 AM, Heiko Stuebner <heiko@sntech.de> wrote:
> Hi Geert,
>
> Am Freitag, 19. Januar 2018, 16:18:20 CET schrieb Geert Uytterhoeven:
>> As of_clk_get_parent_count() returns zero on failure, while
>> of_count_phandle_with_args() might return a negative error code, this
>> also fixes the issue of possibly using a negative number in the
>> allocation below.
>>
>> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
>> ---
>>  drivers/soc/rockchip/pm_domains.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/soc/rockchip/pm_domains.c b/drivers/soc/rockchip/pm_domains.c
>> index 5c342167b9db7a16..9936038d38771784 100644
>> --- a/drivers/soc/rockchip/pm_domains.c
>> +++ b/drivers/soc/rockchip/pm_domains.c
>> @@ -16,6 +16,7 @@
>>  #include <linux/of_address.h>
>>  #include <linux/of_platform.h>
>>  #include <linux/clk.h>
>> +#include <linux/clk-provider.h>
>
> not wanting to be to nitpicky, but clk-provider.h seems that it should be
> used from drivers exposing clocks to the system, not from clock users.
>
> I just remember that in the past clk maintainers tried to keep their
> layering intact, so I've included them for clarification.
>
> Mike, Stephen: the power-domain driver of Rockchip socs needs
> to toggle all clocks of domain peripherals when turning a domain
> on or off, so has a variable list of clocks in the clocks property in dt.
> Hence the of_count_... call which could be replaced with
> of_clk_get_parent_count to not open-code this.

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?

Regards,
Mike

>
>
> Heiko
>
>>  #include <linux/regmap.h>
>>  #include <linux/mfd/syscon.h>
>>  #include <dt-bindings/power/rk3288-power.h>
>> @@ -391,7 +392,7 @@ static int rockchip_pm_add_one_domain(struct rockchip_pmu *pmu,
>>               return -EINVAL;
>>       }
>>
>> -     clk_cnt = of_count_phandle_with_args(node, "clocks", "#clock-cells");
>> +     clk_cnt = of_clk_get_parent_count(node);
>>       pd = devm_kzalloc(pmu->dev,
>>                         sizeof(*pd) + clk_cnt * sizeof(pd->clks[0]),
>>                         GFP_KERNEL);
>>
>
>
Geert Uytterhoeven March 2, 2018, 1:15 p.m. UTC | #3
Hi Mike,

On Sun, Feb 18, 2018 at 8:09 PM, Michael Turquette
<mturquette@baylibre.com> wrote:
> On Sat, Feb 10, 2018 at 8:35 AM, Heiko Stuebner <heiko@sntech.de> wrote:
>> Am Freitag, 19. Januar 2018, 16:18:20 CET schrieb Geert Uytterhoeven:
>>> As of_clk_get_parent_count() returns zero on failure, while
>>> of_count_phandle_with_args() might return a negative error code, this
>>> also fixes the issue of possibly using a negative number in the
>>> allocation below.
>>>
>>> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
>>> ---
>>>  drivers/soc/rockchip/pm_domains.c | 3 ++-
>>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/soc/rockchip/pm_domains.c b/drivers/soc/rockchip/pm_domains.c
>>> index 5c342167b9db7a16..9936038d38771784 100644
>>> --- a/drivers/soc/rockchip/pm_domains.c
>>> +++ b/drivers/soc/rockchip/pm_domains.c
>>> @@ -16,6 +16,7 @@
>>>  #include <linux/of_address.h>
>>>  #include <linux/of_platform.h>
>>>  #include <linux/clk.h>
>>> +#include <linux/clk-provider.h>
>>
>> not wanting to be to nitpicky, but clk-provider.h seems that it should be
>> used from drivers exposing clocks to the system, not from clock users.
>>
>> I just remember that in the past clk maintainers tried to keep their
>> layering intact, so I've included them for clarification.
>>
>> Mike, Stephen: the power-domain driver of Rockchip socs needs
>> to toggle all clocks of domain peripherals when turning a domain
>> on or off, so has a variable list of clocks in the clocks property in dt.
>> Hence the of_count_... call which could be replaced with
>> of_clk_get_parent_count to not open-code this.
>
> 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?

Thanks!

>>>  #include <linux/regmap.h>
>>>  #include <linux/mfd/syscon.h>
>>>  #include <dt-bindings/power/rk3288-power.h>
>>> @@ -391,7 +392,7 @@ static int rockchip_pm_add_one_domain(struct rockchip_pmu *pmu,
>>>               return -EINVAL;
>>>       }
>>>
>>> -     clk_cnt = of_count_phandle_with_args(node, "clocks", "#clock-cells");
>>> +     clk_cnt = of_clk_get_parent_count(node);
>>>       pd = devm_kzalloc(pmu->dev,
>>>                         sizeof(*pd) + clk_cnt * sizeof(pd->clks[0]),
>>>                         GFP_KERNEL);
>>>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
Stephen Boyd March 12, 2018, 10:32 p.m. UTC | #4
Quoting Geert Uytterhoeven (2018-03-02 05:15:35)
> Hi Mike,
> 
> On Sun, Feb 18, 2018 at 8:09 PM, Michael Turquette
> <mturquette@baylibre.com> wrote:
> > 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.
diff mbox

Patch

diff --git a/drivers/soc/rockchip/pm_domains.c b/drivers/soc/rockchip/pm_domains.c
index 5c342167b9db7a16..9936038d38771784 100644
--- a/drivers/soc/rockchip/pm_domains.c
+++ b/drivers/soc/rockchip/pm_domains.c
@@ -16,6 +16,7 @@ 
 #include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/clk.h>
+#include <linux/clk-provider.h>
 #include <linux/regmap.h>
 #include <linux/mfd/syscon.h>
 #include <dt-bindings/power/rk3288-power.h>
@@ -391,7 +392,7 @@  static int rockchip_pm_add_one_domain(struct rockchip_pmu *pmu,
 		return -EINVAL;
 	}
 
-	clk_cnt = of_count_phandle_with_args(node, "clocks", "#clock-cells");
+	clk_cnt = of_clk_get_parent_count(node);
 	pd = devm_kzalloc(pmu->dev,
 			  sizeof(*pd) + clk_cnt * sizeof(pd->clks[0]),
 			  GFP_KERNEL);