> Add suspend frequency support and if needed set it to
> the frequency obtained from the suspend opp (can be defined
> using opp-v2 bindings and is optional).
>
> Signed-off-by: Lin Huang <hl at rock-chips.com>
> ---
> Changes in v2:
> - use update_devfreq() instead devfreq_update_status()
> Changes in v3:
> - fix build error
>
> drivers/devfreq/devfreq.c | 18 ++++++++++++++++--
> drivers/devfreq/governor_simpleondemand.c | 9 +++++++++
> include/linux/devfreq.h | 8 ++++++++
> 3 files changed, 33 insertions(+), 2 deletions(-)
>
>
[]
> +void devfreq_opp_get_suspend_opp(struct device *dev, struct devfreq *devfreq)
> +{
> + struct dev_pm_opp *suspend_opp;
> +
> + rcu_read_lock();
> + suspend_opp = dev_pm_opp_get_suspend_opp(dev);
> + if (suspend_opp)
> + devfreq->suspend_freq = dev_pm_opp_get_freq(suspend_opp);
> + rcu_read_unlock();
> +}
> +EXPORT_SYMBOL(devfreq_opp_get_suspend_opp);
> +
Why do we need this function?
This could be done at the init time (devfreq_add_device).
Plus, when it does not have dev_pm_opp_get_suspend_opp() available,
> /**
> * devfreq_register_opp_notifier() - Helper function to get devfreq notified
> * for any changes in the OPP availability
> diff --git a/drivers/devfreq/governor_simpleondemand.c b/drivers/devfreq/governor_simpleondemand.c
> index ae72ba5..a3efee0 100644
> --- a/drivers/devfreq/governor_simpleondemand.c
> +++ b/drivers/devfreq/governor_simpleondemand.c
> @@ -29,6 +29,15 @@ static int devfreq_simple_ondemand_func(struct devfreq *df,
> struct devfreq_simple_ondemand_data *data = df->data;
> unsigned long max = (df->max_freq) ? df->max_freq : UINT_MAX;
>
> + /*
> + * if devfreq in suspend status and have suspend_freq,
> + * the frequency need to set to suspend_freq
> + */
> + if (df->stop_polling && df->suspend_freq) {
> + *freq = df->suspend_freq;
> + return 0;
> + }
> +
Why are you adding this? "Stop polling" does not necessarily mean that
we are doing suspend-to-RAM/disk. It may really mean just to stop at
the current frequency.
Cheers,
MyungJoo
