Re: [PATCH 2/2] cpufreq: brcmstb-avs-cpufreq: prefer SCMI cpufreq if supported

[Florian Fainelli]

On 04/18/2018 08:56 AM, Markus Mayer wrote:
> From: Jim Quinlan <jim2101...@gmail.com>
> 
> If the SCMI cpufreq driver is supported, we bail, so that the new
> approach can be used.
> 
> Signed-off-by: Jim Quinlan <jim2101...@gmail.com>
> Signed-off-by: Markus Mayer <mma...@broadcom.com>
> ---
>  drivers/cpufreq/brcmstb-avs-cpufreq.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/drivers/cpufreq/brcmstb-avs-cpufreq.c 
> b/drivers/cpufreq/brcmstb-avs-cpufreq.c
> index b07559b9ed99..b4861a730162 100644
> --- a/drivers/cpufreq/brcmstb-avs-cpufreq.c
> +++ b/drivers/cpufreq/brcmstb-avs-cpufreq.c
> @@ -164,6 +164,8 @@
>  #define BRCM_AVS_CPU_INTR    "brcm,avs-cpu-l2-intr"
>  #define BRCM_AVS_HOST_INTR   "sw_intr"
>  
> +#define ARM_SCMI_COMPAT              "arm,scmi"
> +
>  struct pmap {
>       unsigned int mode;
>       unsigned int p1;
> @@ -511,6 +513,20 @@ static int brcm_avs_prepare_init(struct platform_device 
> *pdev)
>       struct device *dev;
>       int host_irq, ret;
>  
> +     /*
> +      * If the SCMI cpufreq driver is supported, we bail, so that the more
> +      * modern approach can be used.
> +      */
> +     if (IS_ENABLED(CONFIG_ARM_SCMI_PROTOCOL)) {
> +             struct device_node *np;
> +
> +             np = of_find_compatible_node(NULL, NULL, ARM_SCMI_COMPAT);
> +             if (np) {
> +                     of_node_put(np);
> +                     return -ENXIO;
> +             }

We would probably want to make sure that the node is also enabled (that
is, does not have a status = "disabled" property) otherwise the check
can be defeated. Something like:

                if (np && of_device_is_available(np))

should be good for that.

Thanks!
-- 
Florian