Re: [PATCH 2/2] cpufreq: mediatek: Add MT8173 cpufreq driver

[Pi-Cheng Chen]

On Wed, Jun 24, 2015 at 4:56 PM, Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote:
> On 24-06-15, 16:44, Pi-Cheng Chen wrote:
>> One reason to put those initialization and resource allocation in probe is
>> that it's easier to handle the return value -PROBE_DEFER from clock
>> and regulator framework when trying to get clocks and regulators
>> consumed by cpufreq driver.
>
> This is the sequence of events if you move these things to ->init().
>
> - your driver's probe()
>   -> cpufreq_register_driver()
>     -> init()
>       -> clk/reg get, failed, return -EPROBE_DEFER
>
> And the failure here will be propagated to probe(). So, it should
> work IMHO.

I will try it.

>
>> The other reason is when the whole system is resuming from suspend,
>> the other subsystem e.g. i2c on which cpufreq driver depends might not
>> ready yet during cpufreq driver initialization. In this case, the cpufreq
>> driver will be blocked when trying to get resources e.g. regulator on i2c
>> bus, and the whole system will stuck for seconds.
>
> That's something else you must investigate on. This dependency should
> be resolved in some other way, I thought DT might have taken care of
> such dependencies.

I will check if it could be solved in some other way.
Thanks.

Pi-Cheng

>
> --
> viresh
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/