On Mon, Aug 21, 2017 at 03:13:32PM +0200, Viresh Kumar wrote:
> The initial idea of creating the cpufreq-dt-platdev.c file was to keep a
> list of platforms that use the "operating-points" (V1) bindings and
> create cpufreq device for them only, as we weren't sure which platforms
> would want the device to get created automatically as some had their own
> cpufreq drivers as well, or wanted to initialize cpufreq after doing
> some stuff from platform code.
>
> But that wasn't the case with platforms using "operating-points-v2"
> property. We wanted the device to get created automatically without the
> need of adding them to the whitelist. Though, we will still have some
> exceptions where we don't want to create the device automatically.
>
> Rename the earlier platform list as *whitelist* and create a new
> *blacklist* as well.
>
> The cpufreq-dt device will get created if:
> - The platform is there in the whitelist OR
> - The platform has "operating-points-v2" property in CPU0's DT node and
> isn't part of the blacklist .
>
> Reported-by: Geert Uytterhoeven <[email protected]>
> Signed-off-by: Viresh Kumar <[email protected]>
>
> I have exercised this on the r8a7795 and r8a7795 with the following reverted:
>
> * 034def597bb7 ("cpufreq: rcar: Add support for R8A7795 SoC")
> * bea2ebca6b91 ("cpufreq: dt: Add r8a7796 support to to use generic cpufreq
> driver")
>
> Tested-by: Simon Horman <[email protected]>
Sorry, I seem to have accidently sent this email as Virish rather than
myself. I will try again.
>
>
> ---
> drivers/cpufreq/cpufreq-dt-platdev.c | 45
> ++++++++++++++++++++++++++++++++----
> 1 file changed, 40 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/cpufreq/cpufreq-dt-platdev.c
> b/drivers/cpufreq/cpufreq-dt-platdev.c
> index bcee384b3251..061b468512a2 100644
> --- a/drivers/cpufreq/cpufreq-dt-platdev.c
> +++ b/drivers/cpufreq/cpufreq-dt-platdev.c
> @@ -9,11 +9,16 @@
>
> #include <linux/err.h>
> #include <linux/of.h>
> +#include <linux/of_device.h>
> #include <linux/platform_device.h>
>
> #include "cpufreq-dt.h"
>
> -static const struct of_device_id machines[] __initconst = {
> +/*
> + * Machines for which the cpufreq device is *always* created, mostly used for
> + * platforms using "operating-points" (V1) property.
> + */
> +static const struct of_device_id whitelist[] __initconst = {
> { .compatible = "allwinner,sun4i-a10", },
> { .compatible = "allwinner,sun5i-a10s", },
> { .compatible = "allwinner,sun5i-a13", },
> @@ -101,21 +106,51 @@ static const struct of_device_id machines[] __initconst
> = {
> { }
> };
>
> +/*
> + * Machines for which the cpufreq device is *not* created, mostly used for
> + * platforms using "operating-points-v2" property.
> + */
> +static const struct of_device_id blacklist[] __initconst = {
> + { }
> +};
> +
> +static bool __init cpu0_node_has_opp_v2_prop(void)
> +{
> + struct device_node *np = of_cpu_device_node_get(0);
> + bool ret = false;
> +
> + if (of_get_property(np, "operating-points-v2", NULL))
> + ret = true;
> +
> + of_node_put(np);
> + return ret;
> +}
> +
> static int __init cpufreq_dt_platdev_init(void)
> {
> struct device_node *np = of_find_node_by_path("/");
> const struct of_device_id *match;
> + const void *data = NULL;
>
> if (!np)
> return -ENODEV;
>
> - match = of_match_node(machines, np);
> + match = of_match_node(whitelist, np);
> + if (match) {
> + data = match->data;
> + goto create_pdev;
> + }
> +
> + if (cpu0_node_has_opp_v2_prop() && !of_match_node(blacklist, np))
> + goto create_pdev;
> +
> of_node_put(np);
> - if (!match)
> - return -ENODEV;
> + return -ENODEV;
>
> +create_pdev:
> + of_node_put(np);
> return PTR_ERR_OR_ZERO(platform_device_register_data(NULL, "cpufreq-dt",
> - -1, match->data,
> + -1, data,
> sizeof(struct cpufreq_dt_platform_data)));
> }
> device_initcall(cpufreq_dt_platdev_init);
