On 04/27/2014 06:41 PM, MyungJoo Ham wrote: >> Some devices use freq_table instead of OPP. For those devices, the >> available_frequencies file shows up empty. Fix that by using freq_table to >> generate the available_frequencies data when it's available. >> >> OPP find frequency APIs also skips frequencies that have been temporarily >> disabled (say, due to thermal, etc). Since available_frequencies is >> supposed to show the entire list of available frequencies without taking >> temporary limits into consideration, preference is given to freq_table when >> available. >> >> Signed-off-by: Saravana Kannan <[email protected]> >> --- >> drivers/devfreq/devfreq.c | 29 ++++++++++++++++++----------- >> 1 file changed, 18 insertions(+), 11 deletions(-) >> >> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c >> index 2042ec3..527cbe2 100644 >> --- a/drivers/devfreq/devfreq.c >> +++ b/drivers/devfreq/devfreq.c >> @@ -912,20 +912,27 @@ static ssize_t available_frequencies_show(struct >> device *d, >> struct devfreq *df = to_devfreq(d); >> struct device *dev = df->dev.parent; >> struct dev_pm_opp *opp; >> + unsigned int i = 0; >> ssize_t count = 0; >> unsigned long freq = 0; >> >> - rcu_read_lock(); >> - do { >> - opp = dev_pm_opp_find_freq_ceil(dev, &freq); >> - if (IS_ERR(opp)) >> - break; >> - >> - count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), >> - "%lu ", freq); >> - freq++; >> - } while (1); >> - rcu_read_unlock(); >> + if (df->profile->freq_table) { >> + for (i = 0; i < df->profile->max_state; i++) >> + count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), >> + "%u ", df->profile->freq_table[i]); > > You are hereby changing the semmantics of the original > available_frequencies node. > > When a frequency/voltage pair has been disabled (opp_disable), probably > by opp_disable(), the frequency is no more "available". > However, when the driver author supplied freq_table as well as OPP > in order to see the statistics, the node will behave differently. > > Please do not affect the current users as long as it does not give > additional benefit or fix a bug.
I was actually trying to stick with the semantics as it was documented. The documentation for this file says it'll show frequencies that are not allowed by the current min/max settings either. To me, an OPP disable seems similar to some frequencies "disabled" by min/max settings. Giving preference to OPP is not a hard change to do, but it seems to go againsts the documented semantics. Thoughts? -Saravana -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
